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Sample records for observations results showed

  1. Simple instruments used in monitoring ionospheric perturbations and some observational results showing the ionospheric responses to the perturbations mainly from the lower atmosphere

    NASA Astrophysics Data System (ADS)

    Xiao, Zuo; Hao, Yongqiang; Zhang, Donghe; Xiao, Sai-Guan; Huang, Weiquan

    Ionospheric disturbances such as SID and acoustic gravity waves in different scales are well known and commonly discussed topics. Some simple ground equipment was designed and used for monitoring continuously the effects of these disturbances, especially, SWF, SFD. Besides SIDs, They also reflect clearly the acoustic gravity waves in different scale and Spread-F and these data are important supplementary to the traditional ionosonde records. It is of signifi-cance in understanding physical essentials of the ionospheric disturbances and applications in SID warning. In this paper, the designing of the instruments is given and results are discussed in detail. Some case studies were introduced as example which showed very clearly not only immediate effects of solar flare, but also the phenomena of ionospheric responses to large scale gravity waves from lower atmosphere such as typhoon, great earthquake and volcano erup-tion. Particularlyresults showed that acoustic gravity waves play significant role in seeding ionospheric Spread-F. These examples give evidence that lower atmospheric activities strongly influence the ionosphere.

  2. Observational astrochemistry - Recent results

    NASA Astrophysics Data System (ADS)

    Irvine, W. M.

    More than 80 molecular species have now been observed in the dense interstellar clouds where stars and planets form or in the envelopes expelled by evolved stars. Elemental constituents of these compounds include all of the biogenic elements, H, C, N, O, S and P. In addition, Si is found in several molecules, and a series of metal halides have recently been detected in the outflowing envelope of a nearby carbon star. Knowledge of the chemical reservoirs for the major volatile elements and a comparison between observed molecular abundances and theoretical models are both discussed.

  3. Observational astrochemistry - Recent results

    NASA Technical Reports Server (NTRS)

    Irvine, W. M.

    1989-01-01

    More than 80 molecular species have now been observed in the dense interstellar clouds where stars and planets form or in the envelopes expelled by evolved stars. Elemental constituents of these compounds include all of the biogenic elements, H, C, N, O, S and P. In addition, Si is found in several molecules, and a series of metal halides have recently been detected in the outflowing envelope of a nearby carbon star. Knowledge of the chemical reservoirs for the major volatile elements and a comparison between observed molecular abundances and theoretical models are both discussed.

  4. GRBs: Recent Observational Results

    NASA Technical Reports Server (NTRS)

    Gehrels, Neil

    2009-01-01

    We are in an exciting period of discovery for gamma-ray bursts. The Swift observatory is detecting 100 bursts per year, providing arcsecond localizations and sensitive observations of the prompt and afterglow emission. The Fermi observatory is observing 250 bursts per year with its medium-energy ORB instrument and about 10 bursts per year with its high-energy LAT instrument. In addition, rapid-response telescopes on the ground are providing new capabilities to study optical emission during the prompt phase and spectral signatures of the host galaxies. The combined data set is enabling great advances in our understanding of GRBs including afterglow physics, short burst origin, and high energy emission. This talk will highlight recent findings.

  5. Safety Observations Achieve Results

    Energy Science and Technology Software Center (ESTSC)

    2000-01-16

    The SOAR web application provides a multi-checklist capability where focused observations can be created to address risk-likely work environments, tasks, etc. The SOAR web application has numerous reports to sort the data by key word, multiple factors (i.e., location, team, behavior, checklist, work environment, etc.), and the highest frequency of behaviors and error-likely predecessors, etc. Other performance indicators are also provided.

  6. 17. Building 202, observation room for test cell, showing panel, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    17. Building 202, observation room for test cell, showing panel, abort button, phones, and observation window. View looking northwest. - Rocket Engine Testing Facility, GRC Building No. 202, NASA Glenn Research Center, Cleveland, Cuyahoga County, OH

  7. Battery Honeycutt Observation Station, closer view showing frame rain; view ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Battery Honeycutt Observation Station, closer view showing frame rain; view northeast - Fort McKinley, Battery Honeycutt Observation Station, East side of East Side Drive, approximately 225 feet south of Cove Side Drive, Great Diamond Island, Portland, Cumberland County, ME

  8. Battery Carpenter Observation Station, collapsed ruin showing south wall; view ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Battery Carpenter Observation Station, collapsed ruin showing south wall; view northeast - Fort McKinley, Battery Carpenter Observation Station, West side of East Side Drive, approximately 275 feet south of Weymouth Way, Great Diamond Island, Portland, Cumberland County, ME

  9. 19. Detail of southeast corner of physical plant showing observation ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    19. Detail of southeast corner of physical plant showing observation lookout (view is looking northwest) - Skinner Meat Packing Plant, Main Plant, 6006 South Twenty-seventh Street, Omaha, Douglas County, NE

  10. Ends of the mine observation tower and transformer buildings, showing ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Ends of the mine observation tower and transformer buildings, showing the separation between them. View facing east - U.S. Naval Base, Pearl Harbor, Waipio Peninsula, Waipo Peninsula, Pearl City, Honolulu County, HI

  11. Battery Berry Observation Station, detail of west side showing former ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Battery Berry Observation Station, detail of west side showing former entry recess and typical sash window; view southeast - Fort McKinley, Battery Berry Observation Station, North side of Wood Side Drive approximately 80 feet east of Spring Cove Lane, Great Diamond Island, Portland, Cumberland County, ME

  12. 1. OVERVIEW SHOWING FIRING CONTROL BLOCKHOUSE 0502 AND ADJACENT OBSERVATION ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. OVERVIEW SHOWING FIRING CONTROL BLOCKHOUSE 0502 AND ADJACENT OBSERVATION TOWER. WATER BRAKE TROUGH SEGMENT AT LOWER RIGHT. Looking north northeast. - Edwards Air Force Base, South Base Sled Track, Firing & Control Blockhouse for 10,000-foot Track, South of Sled Track at midpoint of 20,000-foot track, Lancaster, Los Angeles County, CA

  13. INTERIOR VIEW SHOWING FURNACE KEEPER OBSERVING FURNACE THROUGH BLUE GLASS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR VIEW SHOWING FURNACE KEEPER OBSERVING FURNACE THROUGH BLUE GLASS EVERY TWENTY MINUTES TO DETERMINE SIZE AND TEXTURE OF BATCH AND OTHER VARIABLES. FAN IN FRONT COOLS WORKERS AS THEY CONDUCT REPAIRS. FURNACE TEMPERATURE AT 1572 DEGREES FAHRENHEIT. - Chambers-McKee Window Glass Company, Furnace No. 2, Clay Avenue Extension, Jeannette, Westmoreland County, PA

  14. 14. DETAIL VIEW OF BUTTRESS 4 SHOWING THE RESULTS OF ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    14. DETAIL VIEW OF BUTTRESS 4 SHOWING THE RESULTS OF INADEQUATE TAMPING. THE SIZE OF THE GRANITE AGGREGATE USED IN THE DAMS CONCRETE IS CLEARLY SHOWN. - Hume Lake Dam, Sequioa National Forest, Hume, Fresno County, CA

  15. High-Resolution Observations of a Filament showing Activated Barb

    NASA Astrophysics Data System (ADS)

    Joshi, Anand; Martin, Sara F.; Mathew, Shibu; Srivastava, Nandita

    2012-07-01

    Analysis of a filament showing an activated barb using observations from the Dutch Open Telescope (DOT) on 2010 August 20 are presented. The DOT takes Doppler images in H?, among other wavelengths, in a region about 110 110 arcsec^{2} in area, at a cadence of 30~seconds. The offline image restoration technique of speckle reconstruction is applied to obtain diffraction limited images. The filament developed a new barb in 10~minutes, which disappeared within the next 35~minutes. Such a rapid formation and disappearance of a filament barb is unusual, and has not been reported earlier. Line-of-sight velocity maps were constructed from the Doppler images of the target filament. We observe flows in the filament spine towards the barb location prior to its formation, and flows in the barb towards the spine during its disappearance. Photospheric magnetograms from Heliospheric Magnetic Imager on board the Solar Dynamics Observatory, at a cadence of 45~seconds, were used to determine the changes in magnetic flux in the region surrounding the barb location. The variation of magnetic flux in this duration supports the view that barbs are rooted in minor magnetic polarity. Our analysis shows that barbs can be short-lived and formation and disappearance of the barb was associated with cancellation of magnetic flux.

  16. 13. DETAIL VIEW OF BUTTRESS 4 SHOWING THE RESULTS OF ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    13. DETAIL VIEW OF BUTTRESS 4 SHOWING THE RESULTS OF POOR CONSTRUCTION WORK. THOUGH NOT A SERIOUS STRUCTURAL DEFICIENCY, THE 'HONEYCOMB' TEXTURE OF THE CONCRETE SURFACE WAS THE RESULT OF INADEQUATE TAMPING AT THE TIME OF THE INITIAL 'POUR'. - Hume Lake Dam, Sequioa National Forest, Hume, Fresno County, CA

  17. CASSINI VIMS OBSERVATIONS SHOW ETHANE IS PRESENT IN TITAN'S RAINFALL

    SciTech Connect

    Dalba, Paul A.; Buratti, Bonnie J.; Baines, Kevin H.; Sotin, Christophe; Lawrence, Kenneth J.; Brown, Robert H.; Barnes, Jason W.; Clark, Roger N.; Nicholson, Philip D.

    2012-12-20

    Observations obtained over two years by the Cassini Imaging Science Subsystem suggest that rain showers fall on the surface. Using measurements obtained by the Visual Infrared Mapping Spectrometer, we identify the main component of the rain to be ethane, with methane as an additional component. We observe five or six probable rainfall events, at least one of which follows a brief equatorial cloud appearance, suggesting that frequent rainstorms occur on Titan. The rainfall evaporates, sublimates, or infiltrates on timescales of months, and in some cases it is associated with fluvial features but not with their creation or alteration. Thus, Titan exhibits frequent 'gentle rainfall' instead of, or in addition to, more catastrophic events that cut rivers and lay down large fluvial deposits. Freezing rain may also be present, and the standing liquid may exist as puddles interspersed with patches of frost. The extensive dune deposits found in the equatorial regions of Titan imply multi-season arid conditions there, which are consistent with small, but possibly frequent, amounts of rain, in analogy to terrestrial deserts.

  18. VERITAS Blazar Observations - Recent Results

    SciTech Connect

    Cogan, Peter

    2008-12-24

    We present the discovery of very high energy (VHE) gamma-ray emission from the high-frequency-peaked BL Lac object 1ES 0806+524 (z = 0.138) and the intermediate-frequency-peaked BL Lac object W Comae (z = 0.102) with VERITAS. VHE emission was discovered from these objects during the 2007/2008 observing campaign, with a strong outburst from W Comae detected in mid-March, lasting a few days. Quasi-simultaneous spectral energy distributions are presented, incorporating optical (AAVSO), and X-ray (Swift/RXTE) observations. We also present the energy spectrum of the distant BL Lac (z = 0.182) 1ES 1218+304 which was detected by VERITAS during the 2006/2007 observing campaign. The energy spectrum is discussed in the context of different models of absorption from the diffuse extragalactic background radiation. We present multiwavelength observations of the blazar Markarian 421 (z = 0.03), including a strong flare initially detected by the Whipple 10 m gamma-ray telescope. Finally we present a broadband spectral energy distribution for 1ES 2344+514 (z = 0.044) which is successfully fit using a one zone synchrotron self-Compton model.

  19. Streaming Limit: New Observations and Model Results

    NASA Astrophysics Data System (ADS)

    Ng, C. K.; Reames, D. V.; Tylka, A. J.

    2010-12-01

    Solar energetic particle intensities at 1 AU often show an early temporal plateau where the intensity is limited. This early intensity limit may provide a valuable time window for astronauts to seek shelter before large shock-associated intensity increase (if any). The Ng and Reames (1994) time-dependent model of SEP transport through self-amplified Alfvn waves predicts a maximum proton intensity of ~ 250 particles /(cm^2 s str MeV) at ~ 1 MeV, in agreement within a factor of 2 with the observational survey by Reames and Ng (1998). In fact, streaming-limited intensity is implicit in the steady-state shock-acceleration solution of Bell (1978) and Lee (1983). Further studies on the effect of self-amplified waves on SEP intensity spectra have been made by Ng, Reames and Tylka (2003), Vanio (2003), and Lee (2005). Intensities exceeding the Ng and Reames (1994) limit have been reported (e.g., Lario et al. 2009). We present new observations of multi-species SEP spectra at the temporal intensity plateau. We also present new theoretical results on how the streaming limit depends on ion species and energy, ambient wave intensity spectrum, Alfvn speed, solar-wind speed, shock speed, and the presence of interplanetary shocks and interaction regions. Among the new interesting observations is the strong suppression of ion intensities near 1 MeV/amu in events that have high 10-100 MeV proton intensity. New modeling results confirm that this is due to these low-energy ions being strongly scattered at small pitch angles by waves amplified by 10-100 MeV protons at large pitch angles. As the high-energy protons travel upstream and scatter from small to large pitch-angles, they simultaneously amplify waves en route over a range of wavenumbers, including those that are resonant with low-energy protons. Thus, wave amplification by streaming protons and the pitch-angle dependence of the wave-particle resonance condition are essential factors in understanding the limiting behavior. We thank Glenn Mason for his advice on ACE/ULEIS observations. Work by CKN, DVR, and AJT are supported in part by NASA grants NNX09AU98G, NNX08AQ02G, and NNH09AK79I, respectively.

  20. Observational and Clinical Trial Findings on the Comparative Effectiveness of Diabetes Drugs Showed Agreement

    PubMed Central

    Flory, James H; Mushlin, Alvin I

    2014-01-01

    Objective This study compares an observational study of diabetes treatment effectiveness to randomized controlled trials to assess their convergent validity. Study Design and Setting Multivariable models were developed using observational data to describe change in HbA1c (% unit) and weight (kilograms) after addition of a second-line oral diabetes drug to metformin monotherapy. Randomized trials of these scenarios were systematically identified. The models were used to simulate each trial, and simulated and actual results were compared by linear regression and meta-analysis. Results 32 randomized trials of second-line diabetes oral therapy were identified. For all outcomes and drugs studied, simulation and actual results correlated (p < 0.001). There were no statistically significant differences between meta-analyzed randomized and simulated results for effect on HbA1c. For effect on weight, results were qualitatively comparable, but for sulfonylureas the simulated weight gain was nominally greater than seen in the randomized controlled trials. Conclusions An observational study of diabetes drug effectiveness showed convergent validity with randomized data. This supports cautious use of the observational research to draw conclusions about drug effectiveness in populations not studied in clinical trials. This approach may be useful in other situations where observational and randomized data need integration. PMID:25432086

  1. Radio observations of asteroids: Results and prospects

    NASA Technical Reports Server (NTRS)

    Dickel, J. R.

    1978-01-01

    Radio observations of the asteroids can provide information on the thermal and dielectric properties of the surface materials and because the radio emission arises somewhat below the surface, the data give some indication of layering. Observational difficulty has limited the investigations to only 6 asteroids: 1 Ceres and 324 Bamberga appear to have a layer of dust covering a more compacted material; the data on 4 Vesta cannot be matched by any current models for the surface; and the results for 18 Melpomene, 31 Euphrosyne and 433 Eros are too incomplete for firm conclusions. Future possibilities include more accurate radiometry of a few selected asteroids of different taxonomic classes and actual resolution of some of the larger objects by aperture synthesis techniques.

  2. Gun shows across a multistate American gun market: observational evidence of the effects of regulatory policies

    PubMed Central

    Wintemute, Garen J

    2007-01-01

    Objective To describe gun shows and assess the impact of increased regulation on characteristics linked to their importance as sources of guns used in crime. Design Cross?sectional, observational. Subjects Data were collected at a structured sample of 28 gun shows in California, which regulates these events and prohibits undocumented private party gun sales; and in Arizona, Nevada, Texas and Floridaall leading sources of California's crime gunswhere these restrictions do not exist. Main outcome measures Size of shows, measured by numbers of gun vendors and people in attendance; number and nature of guns for sale by gun vendors; measures of private party gun sales and illegal surrogate (straw) gun purchases. Results Shows in comparison states were larger, but the number of attendees per gun vendor was higher in California. None of these differences was statistically significant. Armed attendees were more common in other states (median 5.7%, interquartile range (IQR) 3.910.0%) than in California (median 1.1%, IQR 0.52.2%), p?=?0.0007. Thirty percent of gun vendors both in California and elsewhere were identifiable as licensed firearm retailers. There were few differences in the types or numbers of guns offered for sale; vendors elsewhere were more likely to sell assault weapons (34.9% and 13.3%, respectively; p?=?0.001). Straw purchases were more common in the comparison states (rate ratio 6.6 (95% CI 0.9 to 49.1), p?=?0.06). Conclusions California's regulatory policies were associated with a decreased incidence of anonymous, undocumented gun sales and illegal straw purchases at gun shows. No significant adverse effects of these policies were observed. PMID:17567968

  3. The Stellar Observations Network Group - first results

    NASA Astrophysics Data System (ADS)

    Antoci, Victoria; Grundahl, Frank; Christensen-Dalsgaard, Joergen; Kjeldsen, Hans

    2015-08-01

    SONG - the Stellar Observations Network Group is a Danish-led project set to design and build a global network of 1-m telescopes to carry out detailed studies of solar-like stars using asteroseismology and to discover and characterise exo-planets and their star system. Here we present more than 100 nights of high-precision radial velocity measurements from 2014 of the subgiant mu Herculis. Preliminary analyses of the largest ground-based data set ever obtained for such as star clearly show the detection of stochastically excited pressure modes. The high quality of our data allows unique extraction of individual modes over many orders in the frequency spectrum, leading to studies of rotation, convection, near-surface effects, core structure using mixed modes and stellar activity.

  4. Observational Results from Mount Stony Brook Observatory

    NASA Astrophysics Data System (ADS)

    Petreshock, J.; Wolk, S.; Adams, N.; Walter, F.

    1995-03-01

    The Mount Stony Brook Observatory consists of a recently upgraded 0.35m Schmidt-Cassegrain telescope instrumented with several CCD cameras. Mt. Stony Brook, located on the Stony Brook campus, in a maritime environment approximately 40 miles East of New York City suffers from poor seeing and a bright sky. However, it offers one major advantage over larger telescopes: availability. We will describe the telescope and instrumentation. We currently use the observatory mainly for determining stellar rotational periods. We will present the results of observations of W Ursae Majoris, an eclipsing contact binary, and FK Comae, a rapidly rotating variable, which confirm our photometric accuracy as well as our period sensitivity. In addition we will be present a new rotational period for the naked T Tauri star TAP 26. TAP 26 was monitored for over 5 months in an attempt to confirm either the 2.51 day period (Bouvier et al. 1993) or the 13 hour period determined by Prosser et al. (1994). We report a 0(d) .715 rotational period and discuss which of the 3 reported periods is likely to be correct.

  5. STS-39 Earth observation of Earth's limb at sunset shows atmospheric layers

    NASA Technical Reports Server (NTRS)

    1991-01-01

    STS-39 Earth observation taken aboard Discovery, Orbiter Vehicle (OV) 103, shows the Earth's limb at sunset with numerous atmospheric scattering layers highlighted. The layers consist of fine particles suspended in very stable layers of the atmosphere. The layers act as a prism for the sunlight.

  6. SOAR remote observing: tactics and early results

    NASA Astrophysics Data System (ADS)

    Cecil, Gerald N.; Crain, J. Adam

    2004-09-01

    Travel from North America to the 4.1m SOAR telescope atop Cerro Pachon exceeds $1000, and takes >16 hours door to door (20+ hours typically). SOAR aims to exploit best seeing, requiring dynamic scheduling that is impossible to accomplish when catering to peripatetic astronomers. According to technical arguments at www.peakoil.org, we are near the peak rate of depleting world petroleum, so can expect travel costs to climb sharply. With the telecom bubble's glut of optical fiber, we can transmit data more efficiently than astronomers and "observe remotely". With data compression, less than half of the 6 Mbps bandwidth shared currently by SOAR and CTIO is enough to enable a high-fidelity observing presence for SOAR partners in North America, Brazil, and Chile. We discuss access from home by cable modem/DSL link.

  7. Astronomy Diagnostic Test Results Reflect Course Goals and Show Room for Improvement

    ERIC Educational Resources Information Center

    LoPresto, Michael C.

    2007-01-01

    The results of administering the Astronomy Diagnostic Test (ADT) to introductory astronomy students at Henry Ford Community College over three years have shown gains comparable with national averages. Results have also accurately corresponded to course goals, showing greater gains in topics covered in more detail, and lower gains in topics covered

  8. Gun Shows and Gun Violence: Fatally Flawed Study Yields Misleading Results

    PubMed Central

    Hemenway, David; Webster, Daniel; Pierce, Glenn; Braga, Anthony A.

    2010-01-01

    A widely publicized but unpublished study of the relationship between gun shows and gun violence is being cited in debates about the regulation of gun shows and gun commerce. We believe the study is fatally flawed. A working paper entitled The Effect of Gun Shows on Gun-Related Deaths: Evidence from California and Texas outlined this study, which found no association between gun shows and gun-related deaths. We believe the study reflects a limited understanding of gun shows and gun markets and is not statistically powered to detect even an implausibly large effect of gun shows on gun violence. In addition, the research contains serious ascertainment and classification errors, produces results that are sensitive to minor specification changes in key variables and in some cases have no face validity, and is contradicted by 1 of its own authors prior research. The study should not be used as evidence in formulating gun policy. PMID:20724672

  9. A negative cloud-to-ground flash showing a number of new and rarely observed features

    NASA Astrophysics Data System (ADS)

    Tran, M. D.; Rakov, V. A.; Mallick, S.

    2014-09-01

    An unusual natural lightning flash containing two branched negative strokes to ground was recorded at the Lightning Observatory in Gainesville, Florida, on 8 June 2013. The flash was apparently a bolt from the blue, whose first-stroke leader emerged from the side of the cloud at a height of about 3.5 km above ground level. The first leader showed profuse branching and what appears to be corona-like formations with spatial extent of 100 to 200 m (probably an intensified portion of radial corona sheath) at the upper part of the channel. Leader branching process facilitated by two simultaneous space stems was observed. The corresponding step lengths were estimated to be 14 and 15 m. The first-stroke attachment process involved a streamer zone about 50 m in length. One of the second-leader branches appeared to abruptly change its direction at the beginning of return stroke process.

  10. Results From Mars Show Electrostatic Charging of the Mars Pathfinder Sojourner Rover

    NASA Technical Reports Server (NTRS)

    Kolecki, Joseph C.; Siebert, Mark W.

    1998-01-01

    Indirect evidence (dust accumulation) has been obtained indicating that the Mars Pathfinder rover, Sojourner, experienced electrostatic charging on Mars. Lander camera images of the Sojourner rover provide distinctive evidence of dust accumulation on rover wheels during traverses, turns, and crabbing maneuvers. The sol 22 (22nd Martian "day" after Pathfinder landed) end-of-day image clearly shows fine red dust concentrated around the wheel edges with additional accumulation in the wheel hubs. A sol 41 image of the rover near the rock "Wedge" (see the next image) shows a more uniform coating of dust on the wheel drive surfaces with accumulation in the hubs similar to that in the previous image. In the sol 41 image, note particularly the loss of black-white contrast on the Wheel Abrasion Experiment strips (center wheel). This loss of contrast was also seen when dust accumulated on test wheels in the laboratory. We believe that this accumulation occurred because the Martian surface dust consists of clay-sized particles, similar to those detected by Viking, which have become electrically charged. By adhering to the wheels, the charged dust carries a net nonzero charge to the rover, raising its electrical potential relative to its surroundings. Similar charging behavior was routinely observed in an experimental facility at the NASA Lewis Research Center, where a Sojourner wheel was driven in a simulated Martian surface environment. There, as the wheel moved and accumulated dust (see the following image), electrical potentials in excess of 100 V (relative to the chamber ground) were detected by a capacitively coupled electrostatic probe located 4 mm from the wheel surface. The measured wheel capacitance was approximately 80 picofarads (pF), and the calculated charge, 8 x 10(exp -9) coulombs (C). Voltage differences of 100 V and greater are believed sufficient to produce Paschen electrical discharge in the Martian atmosphere. With an accumulated net charge of 8 x 10(exp -9) C, and average arc time of 1 msec, arcs can also occur with estimated arc currents approaching 10 milliamperes (mA). Discharges of this magnitude could interfere with the operation of sensitive electrical or electronic elements and logic circuits. Sojourner rover wheel tested in laboratory before launch to Mars. Before launch, we believed that the dust would become triboelectrically charged as it was moved about and compacted by the rover wheels. In all cases observed in the laboratory, the test wheel charged positively, and the wheel tracks charged negatively. Dust samples removed from the laboratory wheel averaged a few ones to tens of micrometers in size (clay size). Coarser grains were left behind in the wheel track. On Mars, grain size estimates of 2 to 10 mm were derived for the Martian surface materials from the Viking Gas Exchange Experiment. These size estimates approximately match the laboratory samples. Our tentative conclusion for the Sojourner observations is that fine clay-sized particles acquired an electrostatic charge during rover traverses and adhered to the rover wheels, carrying electrical charge to the rover. Since the Sojourner rover carried no instruments to measure this mission's onboard electrical charge, confirmatory measurements from future rover missions on Mars are desirable so that the physical and electrical properties of the Martian surface dust can be characterized. Sojourner was protected by discharge points, and Faraday cages were placed around sensitive electronics. But larger systems than Sojourner are being contemplated for missions to the Martian surface in the foreseeable future. The design of such systems will require a detailed knowledge of how they will interact with their environment. Validated environmental interaction models and guidelines for the Martian surface must be developed so that design engineers can test new ideas prior to cutting hardware. These models and guidelines cannot be validated without actual flighata. Electrical charging of vehicles and, one day, astronauts moving across t

  11. Multi-site model-observations comparison shows the diurnal effects of hydrodynamic stress on evapotranspiration

    NASA Astrophysics Data System (ADS)

    Matheny, A. M.; Bohrer, G.

    2013-12-01

    Hydraulic limitations are known to control transpiration in forest ecosystems when the soil is drying or when the vapor pressure deficit between the air and stomata is very large, but they can also impact stomatal apertures under conditions of adequate soil moisture and lower evaporative demand. We use the NACP dataset of latent heat flux (LE) measurements and model observations for multiple site/model intercomparisons to evaluate the degree to which currently un-resolved high-frequency (sub-daily) hydrodynamic stresses affect the error in model prediction of latent heat flux. Particularly, we see that models have difficulty resolving the dynamics of intra-daily hysteresis. We hypothesize that this is a result of un-resolved afternoon stomata closure due to hydrodynamic stresses. We find that although no model or stomata parameterization was consistently best or worst in terms of ability to predict LE, errors in model-simulated LE were consistently largest and most variable when soil moisture and VPD were moderate to limiting. This suggests that models have trouble simulating the dynamics that cause stomata to close due to high VPD and moderate to low soil-water availability. Errors in LE occur most frequently when vegetative dynamics dominate. The majority of models tend to underestimate LE in the pre-noon hours and overestimate in the late evening. These diurnal error patterns are consistent with models' diminished ability to accurately simulate the natural hysteresis of transpiration. Nearly all models demonstrate a marked tendency to underestimate the degree of maximum hysteresis which, across all sites studied, is most pronounced during moisture limited conditions. The assumed empirical or semi-empirical coupling between stomatal conductance and soil moisture used by these current models does not resolve the hydrodynamic process of water movement from the soil to the leaves. This approach does not take advantage of advances in our understanding of water flow and storage in the trees, or of tree and canopy structure. A more thorough representation of the tree-hydrodynamic processes could potentially remedy this significant source of model error. We propose a framework to resolve such tree hydrodynamics in global and regional models. We introduce FETCH - a tree hydrodynamic model that can resolve the fast dynamics of stomatal conductance. We propose that coupling FETCH to other land-surface models would reduce intra-daily errors and improve atmospheric and hydrologic simulations.

  12. Observations of irradiated protostars show a lack of complex organic molecules

    NASA Astrophysics Data System (ADS)

    Lindberg, Johan E.; Charnley, Steven B.; Jørgensen, Jes K.; Watanabe, Yoshimasa; Bisschop, Suzanne; Sakai, Nami; Yamamoto, Satoshi

    2015-08-01

    In their youngest stages, protostars are deeply enshrouded in envelopes of gas and dust, material that later accretes onto the central object and the protoplanetary disc. The icy grain mantles are the formation sites for complex organic molecules. The formation of such molecules is strongly affected by external effects such as heating and irradiation, both due to changes in reaction rates and the evaporation of key species from the ice mantles. To understand these effects, we have studied the molecular composition of irradiated protostars.We demonstrate the strengths of unbiased single-dish line surveys, which we use to study the chemical and physical properties of protostellar envelopes. We have performed line surveys of more than 50 sources in the nearby Corona Australis and Ophiuchus star-forming regions using the APEX telescope. Many of the Corona Australis sources are located near the intermediate-mass Herbig Be star R CrA, and we find that despite its moderate luminosity, the irradiation from this star enhances the H2CO temperatures of the nearby protostellar envelopes from 10 K to at least 30-40 K. This drastically elevated temperature should be of crucial importance to the chemistry of these envelopes, due to thermal evaporation of many key species from the dust grain surfaces.Towards R CrA-IRS7B, the most thoroughly investigated object in our study, we find that the chemistry differs greatly from other thoroughly investigated deeply embedded protostars (hot corinos and warm carbon-chain chemistry sources, WCCC). We find low abundances of complex organic molecules such as CH3OCH3 and CH3CN, but instead elevated abundances of CN and some carbon-chain species like HC3N and C2H, although not to the same level as towards typical WCCC sources. We interpret the observed chemical properties as a result of thermal evaporation of CO from the grain mantles and photo-dissociation reactions in the IRS7B envelope, both initiated by the irradiation from R CrA.

  13. Aortic emboli show surprising size dependent predilection for cerebral arteries: Results from computational fluid dynamics

    NASA Astrophysics Data System (ADS)

    Carr, Ian; Schwartz, Robert; Shadden, Shawn

    2012-11-01

    Cardiac emboli can have devastating consequences if they enter the cerebral circulation, and are the most common cause of embolic stroke. Little is known about relationships of embolic origin/density/size to cerebral events; as these relationships are difficult to observe. To better understand stoke risk from cardiac and aortic emboli, we developed a computational model to track emboli from the heart to the brain. Patient-specific models of the human aorta and arteries to the brain were derived from CT angiography from 10 MHIF patients. Blood flow was modeled by the Navier-Stokes equations using pulsatile inflow at the aortic valve, and physiologic Windkessel models at the outlets. Particulate was injected at the aortic valve and tracked using modified Maxey-Riley equations with a wall collision model. Results demonstrate aortic emboli that entered the cerebral circulation through the carotid or vertebral arteries were localized to specific locations of the proximal aorta. The percentage of released particles embolic to the brain markedly increased with particle size from 0 to ~1-1.5 mm in all patients. Larger particulate became less likely to traverse the cerebral vessels. These findings are consistent with sparse literature based on transesophageal echo measurements. This work was supported in part by the National Science Foundation, award number 1157041.

  14. Swift observations show MAXI J0051-736 is a new outburst of SMC X-2

    NASA Astrophysics Data System (ADS)

    Kennea, J. A.; Burrows, D. N.; Coe, M. J.; Vasilopoulos, A. J. Bird G.; Haberl, F.; Evans, P. A.; Beardmore, A. P.; Krimm, H. A.; Romano, P.; Curran, P.; Yamaoka, K.; Serino, M.; Negoro, H.

    2015-09-01

    At 02:00UT on September 24th, 2015, Swift began a target-of-opportunity of the error region of MAXI J0051-736 (Negoro et al., ATEL #8088). We performed a 7-point tiling observation in Photon Counting mode (PC), with 500s exposure per tile in order to ensure coverage of the MAXI error circle.

  15. Protanopic observers show nearly normal color constancy with natural reflectance spectra

    PubMed Central

    Baraas, Rigmor C.; Foster, David H.; Amano, Kinjiro; Nascimento, Srgio M. C.

    2007-01-01

    The ability of color-deficient observers to discriminate between illuminant changes and surface-reflectance changes in a scene was tested with natural and Munsell reflectance spectra. To avoid the confounding effects of spatial structure, stimuli were simulations of Mondrian-like colored patterns, presented on a computer-controlled color monitor. Protanopes performed less well than normal trichromats, regardless of the type of reflectance spectra, but they were least disadvantaged with patterns comprising reflectance spectra drawn from urban and rural scenes, more characteristic of the natural environment. PMID:15518212

  16. Mars Science Laboratory (MSL) - First Results of Pressure Observations

    NASA Astrophysics Data System (ADS)

    Harri, Ari-Matti; Kahanp, Henrik; Kemppinen, Osku; Genzer, Maria; Gmez-Elvira, Javier; Haberle, Robert M.; Schmidt, Walter; Savijrvi, Hannu; Rodrquez-Manfredi, Jose Antonio; Rafkin, Scott; Polkko, Jouni; Richardson, Mark; Newman, Claire; de la Torre Jurez, Manuel; Martn-Torres, Javier; Paz Zorzano-Mier, Maria; Atlaskin, Evgeny; Kauhanen, Janne; Paton, Mark; Haukka, Harri

    2013-04-01

    The Mars Science laboratory (MSL) called Curiosity made a successful landing at Gale crater early August 2012. MSL has an environmental instrument package called the Rover Environmental Monitoring Station (REMS) as a part of its scientific payload. REMS comprises instrumentation for the observation of atmospheric pressure, temperature of the air, ground temperature, wind speed and direction, relative humidity, and UV measurements. The REMS instrument suite is described at length in [1]. We concentrate on describing the first results from the REMS pressure observations and comparison of the measurements with modeling results. The REMS pressure device is provided by the Finnish Meteorological Institute. It is based on silicon micro-machined capacitive pressure sensors developed by Vaisala Inc. The pressure device makes use of two transducer electronics sections placed on a single multi-layer PCB inside the REMS Instrument Control Unit (ICU) with a filter-protected ventilation inlet to the ambient atmosphere. The absolute accuracy of the pressure device (< 3 Pa) and zero-drift (< 1 Pa/year) enables the investigations of long term and seasonal cycles of the Martian atmosphere. The relative accuracy, or repeatability, in the diurnal time scale is < 1.5 Pa, less than 2 % of the observed diurnal pressure variation at the landing site. The pressure device has special sensors with very high precision (less than 0.2 Pa) that makes it a good tool to study short-term atmospheric phenomena, e.g., dust devils and other convective vortices. The observed MSL pressure data enable us to study both the long term and short-term phenomena of the Martian atmosphere. This would add knowledge of these phenomena to that gathered by earlier Mars missions and modeling experiments [2,3]. Pressure observations are revealing new information on the local atmosphere and climate at Gale crater, and will shed light on the mesoscale and micrometeorological phenomena. Pressure observations show also planet-wide phenomena and are a key observation for enhancing our understanding of the global atmospheric flows and CO2 cycle of the Martian atmosphere. The surface pressure is rising at this time of the Martian season, and this is clearly seen by the MSL pressure observations. The current surface pressure is slightly over 8 hPa, which represents a rise of a few % since the beginning of the mission. Our Mars Limited Area Model (MLAM) produces similar results to the observations with some deviations. They are currently under investigation. References: [1] Gmez-Elvira J. et al. (2012), Space Sci. Rev. 170, 583-640. [2] Haberle, R.M. et al. (2013) Mars, submitted. [3] Smith, M. et al. (2006), J. Geophys. Res., 111, E12S13.

  17. Dysphoric students show higher use of the observer perspective in their retrieval of positive versus negative autobiographical memories.

    PubMed

    Nelis, Sabine; Debeer, Elise; Holmes, Emily A; Raes, Filip

    2013-01-01

    Autobiographical memories are retrieved as images from either a field perspective or an observer perspective. The observer perspective is thought to dull emotion. Positive affect is blunted in depressed mood. Consequently, are positive events recalled from an observer perspective in depressed mood? We investigated the relationship between memory vantage perspective and depressive symptoms in a student sample. Participants completed the Autobiographical Memory Test (AMT; Williams & Broadbent, 1986) and assessed the perspective accompanying each memory. The Beck Depression Inventory-II (BDI-II; Beck, Steer, & Brown, 1996) and the Responses to Positive Affect questionnaire (RPA; Feldman, Joormann, & Johnson, 2008) were administered. The results showed a small positive association between depressive symptoms and the use of an observer perspective for positive autobiographical memories, but not for negative memories. Furthermore, comparing a subgroup with clinically significant symptom levels (dysphoric students) with non-dysphoric individuals revealed that dysphoric students used an observer perspective more for positive memories compared with negative memories. This was not the case for non-dysphoric students. The observer perspective in dysphorics was associated with a dampening cognitive style in response to positive experiences. PMID:23083015

  18. Direct observation shows superposition and large scale flexibility within cytoplasmic dynein motors moving along microtubules.

    PubMed

    Imai, Hiroshi; Shima, Tomohiro; Sutoh, Kazuo; Walker, Matthew L; Knight, Peter J; Kon, Takahide; Burgess, Stan A

    2015-01-01

    Cytoplasmic dynein is a dimeric AAA(+) motor protein that performs critical roles in eukaryotic cells by moving along microtubules using ATP. Here using cryo-electron microscopy we directly observe the structure of Dictyostelium discoideum dynein dimers on microtubules at near-physiological ATP concentrations. They display remarkable flexibility at a hinge close to the microtubule binding domain (the stalkhead) producing a wide range of head positions. About half the molecules have the two heads separated from one another, with both leading and trailing motors attached to the microtubule. The other half have the two heads and stalks closely superposed in a front-to-back arrangement of the AAA(+) rings, suggesting specific contact between the heads. All stalks point towards the microtubule minus end. Mean stalk angles depend on the separation between their stalkheads, which allows estimation of inter-head tension. These findings provide a structural framework for understanding dynein's directionality and unusual stepping behaviour. PMID:26365535

  19. Direct observation shows superposition and large scale flexibility within cytoplasmic dynein motors moving along microtubules

    PubMed Central

    Imai, Hiroshi; Shima, Tomohiro; Sutoh, Kazuo; Walker, Matthew L.; Knight, Peter J.; Kon, Takahide; Burgess, Stan A.

    2015-01-01

    Cytoplasmic dynein is a dimeric AAA+ motor protein that performs critical roles in eukaryotic cells by moving along microtubules using ATP. Here using cryo-electron microscopy we directly observe the structure of Dictyostelium discoideum dynein dimers on microtubules at near-physiological ATP concentrations. They display remarkable flexibility at a hinge close to the microtubule binding domain (the stalkhead) producing a wide range of head positions. About half the molecules have the two heads separated from one another, with both leading and trailing motors attached to the microtubule. The other half have the two heads and stalks closely superposed in a front-to-back arrangement of the AAA+ rings, suggesting specific contact between the heads. All stalks point towards the microtubule minus end. Mean stalk angles depend on the separation between their stalkheads, which allows estimation of inter-head tension. These findings provide a structural framework for understanding dynein's directionality and unusual stepping behaviour. PMID:26365535

  20. Direct observation shows superposition and large scale flexibility within cytoplasmic dynein motors moving along microtubules

    NASA Astrophysics Data System (ADS)

    Imai, Hiroshi; Shima, Tomohiro; Sutoh, Kazuo; Walker, Matthew L.; Knight, Peter J.; Kon, Takahide; Burgess, Stan A.

    2015-09-01

    Cytoplasmic dynein is a dimeric AAA+ motor protein that performs critical roles in eukaryotic cells by moving along microtubules using ATP. Here using cryo-electron microscopy we directly observe the structure of Dictyostelium discoideum dynein dimers on microtubules at near-physiological ATP concentrations. They display remarkable flexibility at a hinge close to the microtubule binding domain (the stalkhead) producing a wide range of head positions. About half the molecules have the two heads separated from one another, with both leading and trailing motors attached to the microtubule. The other half have the two heads and stalks closely superposed in a front-to-back arrangement of the AAA+ rings, suggesting specific contact between the heads. All stalks point towards the microtubule minus end. Mean stalk angles depend on the separation between their stalkheads, which allows estimation of inter-head tension. These findings provide a structural framework for understanding dynein's directionality and unusual stepping behaviour.

  1. Long-Term Trial Results Show No Mortality Benefit from Annual Prostate Cancer Screening

    Cancer.gov

    Thirteen year follow-up data from the Prostate, Lung, Colorectal and Ovarian (PLCO) cancer screening trial show higher incidence but similar mortality among men screened annually with the prostate-specific antigen (PSA) test and digital rectal examination

  2. Observations on recent studies showing increased co-occurrence of autoimmune diseases.

    PubMed

    Sloka, Scott

    2002-05-01

    The co-occurrence of autoimmune diseases has been epidemiologically studied and has aided in our understanding of autoimmunity. However, as new perspectives develop on the pathogenesis and natural history of autoimmune diseases, a refinement in the methodology for the study of the co-occurrence of disease is warranted in order to maximize the information that one may realize from such studies. This paper presents some recent results of co-occurrence studies and then proposes several refinements in the design of epidemiological studies in light of current understanding of the natural history of autoimmune diseases. It also suggests an historical perspective on the results of past studies as to the type of information that can be inferred from them. PMID:12126638

  3. [Continuity of care by Pflegeberleitung? Results of participant observation].

    PubMed

    Brutigam, Christoph; Klettke, Nicole; Kunstmann, Wilfried; Prietz, Angela; Sieger, Margot

    2005-04-01

    Continuity of care between health care institutions is of increasing importance. In a two-year research project on this topic extensive participant observation was carried out for data gathering in three hospitals in Dsseldorf (Germany). In each institution four patients were observed until their discharge and all interactions between them and health care professionals were documented using a semi-structured data-gathering instrument. Furthermore, the researchers questioned the involved professionals after each situation. Altogether a total of 980 situations were documented during 100 shifts, thus professional activities aiming at continuity of care can be regarded as extensively covered. The results show that care professionals (nurses, physicians, social workers etc.) in the three participating hospitals only incompletely assess individual needs or even fail to do so at all. In addition, there is no regular interprofessional collaboration and the professionals' horizon is essentially limited to their own institution. Patients and their relatives are not systematically involved and their views rarely considered. Two cases are used as examples to illustrate these aspects. A third example shows that also successful processes were observed. In most cases, however, the implicit logic of the hospital system dominates over individual needs and therefore a successful continuity of care processes cannot be assumed. Finally, the necessity for a fundamental change of this counterproductive systems logic is briefly discussed. PMID:15869018

  4. Preliminary Results from MCS and MSL Atmospheric Joint Observations

    NASA Astrophysics Data System (ADS)

    Kass, D. M.; Lemmon, M. T.; Mischna, M. A.; de la Torre Juarez, M.; Kleinboehl, A.; McCleese, D. J.; Schofield, J. T.

    2013-12-01

    Starting in May 2013, there has been an ongoing joint atmospheric observations campaign between the Mars Reconnaissance Orbiter (MRO) and the Curiosity Rover (MSL). The observations in the campaign are grouped in four families each at a separate local mean time: 01:30, 04:30, 13:30 and 16:30. The goal is to perform one observation from each family every 5° of Ls (or 10 days). At each joint observation, the Mars Climate Sounder (MCS on MRO) observes the atmosphere above Curiosity with a limb observation to provide a profile of temperature, dust and water ice. At the same time, the Rover Environmental Monitoring Station (REMS) acquires measurements of surface pressure and temperature, near-surface atmospheric temperature, relative humidity and winds, downward UV flux. For many of the observations, column optical depth measurements of aerosols and water vapor are acquired close in time with the Mast Camera (Mastcam) and Chemistry and Camera (ChemCam) by Curiosity. Mars Color Imager (MARCI on MRO) weather images are available for daytime joint observations. The joint observations are being used for several preliminary studies (in addition to providing validation and instrument inter-comparisons). The initial joint observations occurred during the decaying phase of a regional dust storm and show a modest clearing of the atmospheric dust over time. As the season progresses towards aphelion, the overall dust is expected to decrease and equatorial water ice clouds will start to form. MCS provides a vertical profile of the aerosol and distinguishes between dust and ice while column opacity measurements from Mastcam provide the total aerosol column to the surface. While four local times is somewhat constraining, we expect to examine the expression of the diurnal and semi-diurnal tide. We expect to correlate the phasing of the tides in the surface pressure and overlying temperature structure. This should provide an understanding of the local link between the surface and the middle atmosphere provided by the tides. These preliminary results will cover mid-southern summer through mid-northern spring and will examine the rapid transition in the global circulation at the northern spring equinox.

  5. Children of Senegal River Basin show the highest prevalence of Blastocystis sp. ever observed worldwide

    PubMed Central

    2014-01-01

    Background Blastocystis sp. is currently the most common intestinal protist found in human feces and considered an emerging parasite with a worldwide distribution. Because of its potential impact in public health, we reinforced the picture of Blastocystis sp. prevalence and molecular subtype distribution in Africa by performing the first survey of this parasite in Senegal. Methods Stool samples from 93 symptomatic presenting with various gastrointestinal disorders or asymptomatic children living in three villages of the Senegal River Basin were tested for the presence of Blastocystis sp. by non-quantitative and quantitative PCR using primer pairs targeting the SSU rDNA gene. Positive samples were subtyped to investigate the frequency of Blastocystis sp. subtypes in our cohort and the distribution of subtypes in the symptomatic and asymptomatic groups of children. Results By the use of molecular tools, all 93 samples were found to be positive for Blastocystis sp. indicating a striking parasite prevalence of 100%. Mixed infections by two or three subtypes were identified in eight individuals. Among a total of 103 subtyped isolates, subtype 3 was most abundant (49.5%) followed by subtype 1 (28.2%), subtype 2 (20.4%) and subtype 4 (1.9%). Subtype 3 was dominant in the symptomatic group while subtypes 1 and 2 were detected with equal frequency in both symptomatic and asymptomatic groups. The distribution of subtypes was compared with those available in other African countries and worldwide. Comparison confirmed that subtype 4 is much less frequently detected or absent in Africa while it is commonly found in Europe. Potential sources of Blastocystis sp. infection including human-to-human, zoonotic, and waterborne transmissions were also discussed. Conclusions The prevalence of Blastocystis sp. in our Senegalese population was the highest prevalence ever recovered worldwide for this parasite by reaching 100%. All cases were caused by subtypes 1, 2, 3 and 4 with a predominance of subtype 3. More than half of the children infected by Blastocystis sp. presented various gastrointestinal disorders. Such high prevalence of blastocystosis in developing countries makes its control a real challenge for public health authorities. PMID:24666632

  6. Televised medical talk showswhat they recommend and the evidence to support their recommendations: a prospective observational study

    PubMed Central

    Kolber, Michael R; McCormack, James; Lam, Vanessa; Overbo, Kate; Cotton, Candra; Finley, Caitlin; Turgeon, Ricky D; Garrison, Scott; Lindblad, Adrienne J; Banh, Hoan Linh; Campbell-Scherer, Denise; Vandermeer, Ben; Allan, G Michael

    2014-01-01

    Objective To determine the quality of health recommendations and claims made on popular medical talk shows. Design Prospective observational study. Setting Mainstream television media. Sources Internationally syndicated medical television talk shows that air daily (The Dr Oz Show and The Doctors). Interventions Investigators randomly selected 40 episodes of each of The Dr Oz Show and The Doctors from early 2013 and identified and evaluated all recommendations made on each program. A group of experienced evidence reviewers independently searched for, and evaluated as a team, evidence to support 80 randomly selected recommendations from each show. Main outcomes measures Percentage of recommendations that are supported by evidence as determined by a team of experienced evidence reviewers. Secondary outcomes included topics discussed, the number of recommendations made on the shows, and the types and details of recommendations that were made. Results We could find at least a case study or better evidence to support 54% (95% confidence interval 47% to 62%) of the 160 recommendations (80 from each show). For recommendations in The Dr Oz Show, evidence supported 46%, contradicted 15%, and was not found for 39%. For recommendations in The Doctors, evidence supported 63%, contradicted 14%, and was not found for 24%. Believable or somewhat believable evidence supported 33% of the recommendations on The Dr Oz Show and 53% on The Doctors. On average, The Dr Oz Show had 12 recommendations per episode and The Doctors 11. The most common recommendation category on The Dr Oz Show was dietary advice (39%) and on The Doctors was to consult a healthcare provider (18%). A specific benefit was described for 43% and 41% of the recommendations made on the shows respectively. The magnitude of benefit was described for 17% of the recommendations on The Dr Oz Show and 11% on The Doctors. Disclosure of potential conflicts of interest accompanied 0.4% of recommendations. Conclusions Recommendations made on medical talk shows often lack adequate information on specific benefits or the magnitude of the effects of these benefits. Approximately half of the recommendations have either no evidence or are contradicted by the best available evidence. Potential conflicts of interest are rarely addressed. The public should be skeptical about recommendations made on medical talk shows. Additional details of methods used and changes made to study protocol PMID:25520234

  7. Preliminary Results from Coordinated UVCS-CDS-Ulysses Observations

    NASA Technical Reports Server (NTRS)

    Parenti, S.; Bromage, B. J.; Poletto, G.; Suess, S. T.; Raymond, J. C.; Noci, G.; Bromage, G. E.; Rose, M. Franklin (Technical Monitor)

    2001-01-01

    The June 2000 quadrature between the Sun, Earth, and Ulysses took place with Ulysses at a distance of 3.35 AU from the Sun and at heliocentric latitude 58.2 deg south, in the southeast quadrant. This provided an opportunity to observe the corona close to the Sun with Coronal Diagnostic Spectrometer (CDS) and Ultraviolet Coronograph Spectrometer (UVCS) and, subsequently, to sample the same plasma when it reached Ulysses. Here we focus on simultaneous observations of UVCS and CDS made on June 12, 13, 16 and 17. The UVCS data were acquired at heliocentric altitudes ranging from 1.6 to 2.2 solar radii, using different grating positions, in order to get a wide wavelength range. CDS data consisted of Normal Incidence Spectrometer (NIS) full wavelength rasters of 120" x 150" centered at altitudes up to 1.18 solar radii, together with Grazing Incidence Spectrometer (GIS) 4" x 4" rasters within the same field of view, out to 1.2 solar radii. The radial direction to Ulysses passed through a high latitude streamer, throughout the 4 days of observations, Analysis of the spectra taken by UVCS shows a variation of the element abundances in the streamer over our observing interval: however, because the observations were in slightly different parts of the streamer on different days, the variation could be ascribed either to a temporal or spatial effect. The oxygen abundance, however, seems to increase at the edge of the streamer, as indicated by previous analyses. This suggests the variation may be a function of position within the streamer, rather than a temporal effect. Oxygen abundances measured by SWICS on Ulysses are compared with the CDS and UVCS results to see whether changes measured in situ follow the same pattern.

  8. Comb-Push Ultrasound Shear Elastography of Breast Masses: Initial Results Show Promise

    PubMed Central

    Song, Pengfei; Fazzio, Robert T.; Pruthi, Sandhya; Whaley, Dana H.; Chen, Shigao; Fatemi, Mostafa

    2015-01-01

    Purpose or Objective To evaluate the performance of Comb-push Ultrasound Shear Elastography (CUSE) for classification of breast masses. Materials and Methods CUSE is an ultrasound-based quantitative two-dimensional shear wave elasticity imaging technique, which utilizes multiple laterally distributed acoustic radiation force (ARF) beams to simultaneously excite the tissue and induce shear waves. Female patients who were categorized as having suspicious breast masses underwent CUSE evaluations prior to biopsy. An elasticity estimate within the breast mass was obtained from the CUSE shear wave speed map. Elasticity estimates of various types of benign and malignant masses were compared with biopsy results. Results Fifty-four female patients with suspicious breast masses from our ongoing study are presented. Our cohort included 31 malignant and 23 benign breast masses. Our results indicate that the mean shear wave speed was significantly higher in malignant masses (6 1.58 m/s) in comparison to benign masses (3.65 1.36 m/s). Therefore, the stiffness of the mass quantified by the Youngs modulus is significantly higher in malignant masses. According to the receiver operating characteristic curve (ROC), the optimal cut-off value of 83 kPa yields 87.10% sensitivity, 82.61% specificity, and 0.88 for the area under the curve (AUC). Conclusion CUSE has the potential for clinical utility as a quantitative diagnostic imaging tool adjunct to B-mode ultrasound for differentiation of malignant and benign breast masses. PMID:25774978

  9. Scheduling Results for the THEMIS Observation Scheduling Tool

    NASA Technical Reports Server (NTRS)

    Mclaren, David; Rabideau, Gregg; Chien, Steve; Knight, Russell; Anwar, Sadaat; Mehall, Greg; Christensen, Philip

    2011-01-01

    We describe a scheduling system intended to assist in the development of instrument data acquisitions for the THEMIS instrument, onboard the Mars Odyssey spacecraft, and compare results from multiple scheduling algorithms. This tool creates observations of both (a) targeted geographical regions of interest and (b) general mapping observations, while respecting spacecraft constraints such as data volume, observation timing, visibility, lighting, season, and science priorities. This tool therefore must address both geometric and state/timing/resource constraints. We describe a tool that maps geometric polygon overlap constraints to set covering constraints using a grid-based approach. These set covering constraints are then incorporated into a greedy optimization scheduling algorithm incorporating operations constraints to generate feasible schedules. The resultant tool generates schedules of hundreds of observations per week out of potential thousands of observations. This tool is currently under evaluation by the THEMIS observation planning team at Arizona State University.

  10. Dark Clouds in the ISOGAL survey: Observational Results.

    NASA Astrophysics Data System (ADS)

    Teyssier, D.; Pérault, M.; Hennebelle, P.

    The ISOGAL survey was a galactic survey conducted in the mid-infrared with the ISO camera, under the leadership of A. Omont. Its purposes included the study of stellar populations and galactic structure (bulge and inner Galaxy up to longitudes of 60circ), as well as the emission and absorption due to the interstellar medium. Among the first results of this survey (Pérault et al., 1996) is the evidence of narrow (down to 10'' in size) absorbing filaments and globules which appear as dark features in the 7 or 15 microns images. We present here follow-up observations of the infrared dark features conducted at the IRAM 30-m telescope. The analysis of the CO isotope and continuum maps showed spectacular spatial correlation with the mid-IR absorption. These features are distributed as far as the prominent molecular ring area in the inner Galaxy (2-8 kpc), making them first detection of individual dark clouds away from the Solar Neighbourhood. The clouds exhibit shapes ranging from globules to thin filament down to 0.3 pc in size. The on-the-fly images obtained in C18O confirmed that the cores are dense, compact molecular emitters, significantly more massive than local dark clouds (more than 1000 Modot) and lie within low activity Giant Molecular Clouds (GMC's). Despite the high visual extinction values inferred in the mid-IR data (Av >= 25, Hennebelle et al, 2000), the CO isotope lines are surprisingly weak, indicating possible depletion onto grains. Complementary observations of temperature and density probes (mainly HC3N and CH3CCH) confirmed this trend and led to first estimates of kinetic temperature around 10 K or less and densities above 105 cm-3. Comparisons with similar observations done by the MSX project (Egan et al., 1998) are discussed.

  11. NEOWISE OBSERVATIONS OF NEAR-EARTH OBJECTS: PRELIMINARY RESULTS

    SciTech Connect

    Mainzer, A.; Bauer, J.; Masiero, J.; Eisenhardt, P.; Grav, T.; Mo, W.; McMillan, R. S.; Cutri, R. M.; Walker, R.; Wright, E.; Tholen, D. J.; Jedicke, R.; Denneau, L.; Spahr, T.; DeBaun, E.; Elsbury, D.; Gautier, T.; Gomillion, S.; Hand, E.; Watkins, J.; and others

    2011-12-20

    With the NEOWISE portion of the Wide-field Infrared Survey Explorer (WISE) project, we have carried out a highly uniform survey of the near-Earth object (NEO) population at thermal infrared wavelengths ranging from 3 to 22 {mu}m, allowing us to refine estimates of their numbers, sizes, and albedos. The NEOWISE survey detected NEOs the same way whether they were previously known or not, subject to the availability of ground-based follow-up observations, resulting in the discovery of more than 130 new NEOs. The survey's uniform sensitivity, observing cadence, and image quality have permitted extrapolation of the 428 near-Earth asteroids (NEAs) detected by NEOWISE during the fully cryogenic portion of the WISE mission to the larger population. We find that there are 981 {+-} 19 NEAs larger than 1 km and 20,500 {+-} 3000 NEAs larger than 100 m. We show that the Spaceguard goal of detecting 90% of all 1 km NEAs has been met, and that the cumulative size distribution is best represented by a broken power law with a slope of 1.32 {+-} 0.14 below 1.5 km. This power-law slope produces {approx}13, 200 {+-} 1900 NEAs with D > 140 m. Although previous studies predict another break in the cumulative size distribution below D {approx} 50-100 m, resulting in an increase in the number of NEOs in this size range and smaller, we did not detect enough objects to comment on this increase. The overall number for the NEA population between 100 and 1000 m is lower than previous estimates. The numbers of near-Earth comets and potentially hazardous NEOs will be the subject of future work.

  12. Results of the First Observations with the Hamburg Robotic Telescope

    NASA Astrophysics Data System (ADS)

    Mittag, M.; Hempelmann, A.; Gonzlez-Prez, J. N.; Schmitt, J. H. M. M.; Hall, J. C.

    2011-12-01

    The results of the first scientific observations with the Hamburg Robotic Telescope (HRT) are presented. These observations were performed between October 2008 and August 2009. The goals of this program were a test of the observational performance of the telescope and the creation of a transformation equation from the HRT S-index to the Mount Wilson S-index. The mean of the deviations between the transformed HRT S-Indices and the corresponding Mount Wilson S-Indices is ?4%. These deviations can be -- at least partially -- explained by stellar variability and the non-simultaneity of the observations. Furthermore, the first monitoring of several stars was performed.

  13. Severe Septic Patients with Mitochondrial DNA Haplogroup JT Show Higher Survival Rates: A Prospective, Multicenter, Observational Study

    PubMed Central

    Martn, Mara M.; Lpez-Gallardo, Esther; Sol-Violn, Jordi; Blanquer, Jos; Labarta, Lorenzo; Daz, Csar; Borreguero-Len, Juan Mara; Jimnez, Alejandro; Montoya, Julio; Ruiz-Pesini, Eduardo

    2013-01-01

    Objective In a previous cohort study (n=96), we found an association between mitochondrial (mt) DNA haplogroup JT and increased survival of severe septic patients, after controlling for age and serum lactic acid levels. The aim of this research was to increase the predictive accuracy and to control for more confounder variables in a larger cohort (n=196) of severe septic patients, to confirm whether mtDNA haplogroup JT influences short and medium-term survival in these patients. Methods We conducted a prospective, multicenter, observational study in six Spanish Intensive Care Units. We determined 30-day and 6-month survival and mtDNA haplogroup in this second cohort of 196 patients and in the global cohort (first and second cohorts combined) with 292 severe septic patients. Multiple logistic regression and Cox regression analyses were used to test for the association of mtDNA haplogroups JT with survival at 30-days and 6-months, controlling for age, sex, serum interleukin-6 levels and SOFA score. Results Logistic and Cox regression analyses showed no differences in 30-day and 6-month survival between patients with mtDNA haplogroup JT and other haplogroups in the first cohort (n=96). In the second cohort (n=196), these analyses showed a trend to higher 30-day and 6-month survival in those with haplogroup JT. In the global cohort (n=292), logistic and Cox regression analyses showed higher 30-day and 6-month survival for haplogroup JT. There were no significant differences between J and T sub-haplogroups in 30-day and 6-month survival. Conclusions The global cohort study (first and second cohorts combined), the largest to date reporting on mtDNA haplogroups in septic patients, confirmed that haplogroup JT patients showed increased 30-day and 6-month survival. This finding may be due to single nucleotide polymorphism defining the whole haplogroup JT and not separately for J or T sub-haplogroups. PMID:24069186

  14. Arctic precipitation and evaporation: Model results and observational estimates

    SciTech Connect

    Walsh, J.E.; Portis, D.; Kattsov, V.; Meleshko, V.

    1998-01-01

    Observational estimates of Precipitation and evaporation over the Arctic Ocean and its terrestrial watersheds are compared with corresponding values from the climate model simulations of the Atmospheric Model Intercomparison Project (AMIP). Estimates of Arctic regional mean precipitation from several observational sources show considerable scatter, and the observational estimates based on gauge-adjusted station data are considerably larger than the other observational estimates. While the AMIP model simulations of precipitation also show scatter, the ensemble mean of the models` precipitation exceeds even the higher (gauge-adjusted) observational estimates over the Arctic Ocean and its major watersheds. The difference between simulated precipitation and evaporation (P-E), representing the net freshwater gain (runoff) by the surface, also exceeds the observational estimates by 44%-83% over the Arctic Ocean and by generally smaller percentages over the terrestrial watersheds. The ensemble model mean of the annual P - E exceeds the corresponding river discharges of the Ob and Mackenzie Rivers by 62% and 14%, respectively. The simulated P and E are highly correlated across the AMIP models, and the interannual (as well as the seasonal) variations of P and E are highly correlated in the output of most of the individual models, implying a coupling of the regional P and E in the models. The only formulational feature found to be common to the high-P (and high-E) models is the use of a specified rather than a computed soil moisture. A preliminary examination of the reanalyses of the National Centers for Environmental Prediction shows that the differences between the reanalysis-derived P and E are closer to the observational estimates than are the AMIP estimates. However, the magnitudes of the reanalysis-derived P and E, individually, are higher than the corresponding observational estimates. 25 refs., 16 figs., 4 tabs.

  15. Sustained observations in the Weddell Sea spanning more than 20 years show gradual increase of the deep water heat content

    NASA Astrophysics Data System (ADS)

    Strass, Volker; Rohardt, Gerd; Hoppema, Mario

    2014-05-01

    Beginning in 1989, Eberhard Fahrbach established and maintained until his premature death an observational programme in the Weddell Sea, which outstandingly contributed to alleviate the grave problem of undersampling of the Southern Ocean. Continuation of his legacy by the Alfred-Wegener-Institut has yielded a time series that now extends into 2013, hence covers almost 24 years. Here we analyse this data set for long-term changes of the heat content in the deep Weddell Sea. We exclusively evaluate the calibrated temperature records obtained with ship-lowered CTD (conductivity-temperature-depth sonde) casts at repeated hydrographic stations and along repeated sections. Using this approach we avoid introducing potential temperature offsets that can result from combination of different measurement technologies and potential biases resultant from differences in geographic positions. Our results show that the deep water masses below 700 m gradually warmed over the past two decades by 0.001 - 0.004 K a-1. Superimposed inter-annual to multi-annual variations appear as largely uncorrelated horizontally across the Weddell Gyre. The long-term (21 - 24 years) trends of increasing temperatures in different depth layers below 700 m at all stations and sections can be approximated by linear regression that explains between 27 and 91 % of the variance, where the coefficients of correlation tend to increase with depth. No significant trends are found in the top 700 m. The heating rate of the water masses below 700 m is estimated to 0.79 ± 0.14 W m-2, which is more than twice as high as determined for the global deep ocean in general. Our results hence corroborate the view that Southern Ocean processes make an above-average contribution to the deep ocean warming, and so add to bring global estimates of the deep ocean heating rate and of the net energy flux into the Earth's climate system at the top of the atmosphere of 0.5 - 1 W m-2 closer in line with each other. Thus they help to resolve the problem of the 'missing heat' or 'missing energy', respectively, terms coined to grasp the observation that surface temperatures of planet Earth have stalled rising since about 15 years while radiation-affecting atmospheric CO2 concentrations continued to increase. Our results support the finding that excess energy which results from changes in the Earth' radiation balance is transferred into heating of the deep ocean, where it does not contribute to an increase of surface temperatures but inevitably enhances thermosteric sea level rise.

  16. Spectral Results of the Magnetic Fluctuations Observed in MCX

    NASA Astrophysics Data System (ADS)

    Uzun-Kaymak, Ilker; Choi, S.; Clary, R.; Ellis, R.; Hassam, A.; Teodorescu, C.

    2007-11-01

    The Maryland Centrifugal Experiment (MCX) is set up to study centrifugal confinement and supersonic rotation. MCX is a magnetic mirror machine with end fields up to 2T independent of the mid-plane magnetic field. A radial electric field created by biasing the inner electrode with respect to outer wall is used to drive azimuthal rotation, i.e., E x B rotation. Previously, a small number of Bdot coils have been employed at the edge of the plasma to investigate the modes of operation. Preliminary results show that there are dominant modes associated with the E x B rotation. In order to assess magnetic fluctuations and the E x B rotation fully, 25 Bdot coils mounted on various locations inside MCX are utilized. Here we present the analysis of the observed spectral modes by means of the power spectrum and the bispectrum to focus on the nonlinear coupling among various m-modes. We will also address low frequency magnetic field perturbations via proper filtering process.

  17. Do monkey F5 mirror neurons show changes in firing rate during repeated observation of natural actions?

    PubMed

    Kilner, J M; Kraskov, A; Lemon, R N

    2014-03-01

    Mirror neurons were first discovered in area F5 of macaque monkeys. In humans, noninvasive studies have demonstrated an increased blood oxygen level-dependent (BOLD) signal in homologous motor areas during action observation. One approach to demonstrating that this indicates the existence of mirror neurons in humans has been to employ functional (f)MRI adaptation to test whether the same population of neurons is active during both observation and execution conditions. Although a number of human studies have reported fMRI adaptation in these areas, a recent study has shown that macaque mirror neurons do not attenuate their firing rate with two repetitions. Here we investigated whether mirror neurons modulate their firing rate when monkeys observed the same repeated natural action multiple times. We recorded from 67 mirror neurons in area F5 of two macaque monkeys while they observed an experimenter perform a reach-to-grasp action on a small food reward using a precision grip. Although no changes were detectable for the first two repetitions, we show that both the firing rate and the latency at which mirror neurons discharged during observation were subtly modulated by the repetition of the observed action over 7-10 trials. Significant adaption was mostly found in the period immediately before the grasp was performed. We also found that the local field potential activity in F5 (beta-frequency range, 16-23 Hz), which is attenuated during action observation, also showed systematic changes with repeated observation. These LFP changes occurred well in advance of the mirror neuron adaptation. We conclude that macaque mirror neurons can show intra-modal adaptation, but whether this is related to fMRI adaptation of the BOLD signal requires further investigation. PMID:24371289

  18. Do monkey F5 mirror neurons show changes in firing rate during repeated observation of natural actions?

    PubMed Central

    Kraskov, A.; Lemon, R. N.

    2013-01-01

    Mirror neurons were first discovered in area F5 of macaque monkeys. In humans, noninvasive studies have demonstrated an increased blood oxygen level-dependent (BOLD) signal in homologous motor areas during action observation. One approach to demonstrating that this indicates the existence of mirror neurons in humans has been to employ functional (f)MRI adaptation to test whether the same population of neurons is active during both observation and execution conditions. Although a number of human studies have reported fMRI adaptation in these areas, a recent study has shown that macaque mirror neurons do not attenuate their firing rate with two repetitions. Here we investigated whether mirror neurons modulate their firing rate when monkeys observed the same repeated natural action multiple times. We recorded from 67 mirror neurons in area F5 of two macaque monkeys while they observed an experimenter perform a reach-to-grasp action on a small food reward using a precision grip. Although no changes were detectable for the first two repetitions, we show that both the firing rate and the latency at which mirror neurons discharged during observation were subtly modulated by the repetition of the observed action over 7–10 trials. Significant adaption was mostly found in the period immediately before the grasp was performed. We also found that the local field potential activity in F5 (beta-frequency range, 16–23 Hz), which is attenuated during action observation, also showed systematic changes with repeated observation. These LFP changes occurred well in advance of the mirror neuron adaptation. We conclude that macaque mirror neurons can show intra-modal adaptation, but whether this is related to fMRI adaptation of the BOLD signal requires further investigation. PMID:24371289

  19. Editorial: solar radiophysics recent results on observations and theories

    NASA Astrophysics Data System (ADS)

    Nakariakov, Valery M.; Kashapova, Larisa K.; Yan, Yi-Hua

    2014-07-01

    Solar radiophysics is a rapidly developing branch of solar physics and plasma astrophysics. Solar radiophysics has the goal of analyzing observations of radio emissions from the Sun and understanding basic physical processes operating in quiet and active regions of the solar corona. In the near future, the commissioning of a new generation of solar radio observational facilities, which include the Chinese Spectral Radio Heliograph (CSRH) and the upgrade of the Siberian Solar Radio Telescope (SSRT), and the beginning of solar observations with the Atacama Large Millimeter/submillimeter Array (ALMA), is expected to bring us new breakthrough results of a transformative nature. The Marie-Curie International Research Staff Exchange (MC IRSES) RadioSun international network aims to create a solid foundation for the successful exploitation of upcoming solar radio observational facilities, as well as intensive use of the existing observational tools, advanced theoretical modeling of relevant physical processes and observables, and training a new generation of solar radio physicists. The RadioSun network links research teams from China, Czech Republic, Poland, Russia and the UK. This mini-volume presents research papers based on invited reviews and contributed talks at the 1st RadioSun workshop in China. These papers cover a broad range of research topics and include recent observational and theoretical advances in solar radiophysics, MHD seismology of the solar corona, physics of solar flares, generation of radio emission, numerical modeling of MHD and plasma physics processes, charged-particle acceleration and novel instrumentation.

  20. Mars Science Laboratory relative humidity observations: Initial results

    PubMed Central

    Harri, A-M; Genzer, M; Kemppinen, O; Gomez-Elvira, J; Haberle, R; Polkko, J; Savijrvi, H; Renn, N; Rodriguez-Manfredi, JA; Schmidt, W; Richardson, M; Siili, T; Paton, M; Torre-Juarez, M De La; Mkinen, T; Newman, C; Rafkin, S; Mischna, M; Merikallio, S; Haukka, H; Martin-Torres, J; Komu, M; Zorzano, M-P; Peinado, V; Vazquez, L; Urqui, R

    2014-01-01

    The Mars Science Laboratory (MSL) made a successful landing at Gale crater early August 2012. MSL has an environmental instrument package called the Rover Environmental Monitoring Station (REMS) as a part of its scientific payload. REMS comprises instrumentation for the observation of atmospheric pressure, temperature of the air, ground temperature, wind speed and direction, relative humidity (REMS-H), and UV measurements. We concentrate on describing the REMS-H measurement performance and initial observations during the first 100 MSL sols as well as constraining the REMS-H results by comparing them with earlier observations and modeling results. The REMS-H device is based on polymeric capacitive humidity sensors developed by Vaisala Inc., and it makes use of transducer electronics section placed in the vicinity of the three humidity sensor heads. The humidity device is mounted on the REMS boom providing ventilation with the ambient atmosphere through a filter protecting the device from airborne dust. The final relative humidity results appear to be convincing and are aligned with earlier indirect observations of the total atmospheric precipitable water content. The water mixing ratio in the atmospheric surface layer appears to vary between 30 and 75 ppm. When assuming uniform mixing, the precipitable water content of the atmosphere is ranging from a few to six precipitable micrometers. Key Points Atmospheric water mixing ratio at Gale crater varies from 30 to 140 ppm MSL relative humidity observation provides good data Highest detected relative humidity reading during first MSL 100 sols is RH75% PMID:26213667

  1. Initial Results Derived from JEM-GLIMS Observations

    NASA Astrophysics Data System (ADS)

    Sato, M.; Ushio, T.; Morimoto, T.; Kobayashi, N.; Takahashi, Y.; Suzuki, M.; Yamazaki, A.; Inan, U.; Linscott, I.; Hobara, Y.

    2012-12-01

    In order to identify the spatial distributions and occurrence conditions of TLEs, JEM-GLIMS (Global Lightning and sprIte MeasurementS on JEM-EF) observations from Japanese Experiment Module - Exposed Facility (JEM-EF) at International Space Station (ISS) will start this year. Science instruments of JEM-GLIMS consist of two kinds of optical detectors and two kinds of radio receivers. The optical instruments are two wide FOV CMOS cameras (LSI) and six-channel spectrophotometers (PH). LSI uses a CMOS device with 512x512 pixels as an imaging sensor and uses a CCTV lens with =25 mm/F=1.4 which becomes 28.3x28.3 deg. FOV. LSI-1 equips a wide band optical filter (766-832 nm) and mainly measures lightning emission, while LSI-2 equips a narrowband optical filter (762+/-7 nm) and mainly measures TLE emission. Five of six PH channels employ the optics with 42.7 deg. conical FOV and use photomultiplier tubes (PMTs) as photon detectors. Each channel of these photometers equips an optical band-pass filter to measure N2 1P, 2P, and LBH emissions. One of six photometers employs a wide-FOV optics (86.8 deg.) and wide-band filter to measure N2 1P lightning emission. All these optical instruments are pointed to the nadir direction. In order to detect whistler wave excited by lightning discharges, one VLF receiver (VLFR) is installed. VLFR consists of a 15 cm nadir-directing monopole antenna and an electronics unit recording waveform data with a sampling frequency of 100 kHz with 14-bit resolution. In addition to this, two sets of VHF receivers (VITF) are also installed to measure VHF pulses emitted by lightning discharges. VITF consists of two patch-type antennas separated by 1.5 m and an electronics unit which records pulse data with a sampling frequency of 200 MHz with 8-bit resolution. Thus, the spatial and temporal evolution of lightning and TLEs can be measured by the two optical instruments, while the electrical characteristics of sprite-inducing lightning discharges can be measured by two radio receivers. JEM-GIMS was successfully launched by H-IIB rocket at 02:06:18 UT on July 21, 2012 and transported to ISS by the HTV-3 cargo transfer spaceship. HTV-3 successfully arrived at ISS on July 27 and our JEM-GLIMS instruments will be installed at JEM-EF on August 9. For the period from September 15 to 21 we will carry out the initial checkout operation, and finally we will start continuous TLE observations from the middle of October. At the presentation we will show the test results obtained during the checkout operations and will present the initial results derived from JEM-GLIMS lightning/TLE observations.

  2. WISE/NEOWISE Observations of the Jovian Trojans: Preliminary Results

    NASA Astrophysics Data System (ADS)

    Grav, T.; Mainzer, A. K.; Bauer, J.; Masiero, J.; Spahr, T.; McMillan, R. S.; Walker, R.; Cutri, R.; Wright, E.; Eisenhardt, P. R. M.; Blauvelt, E.; DeBaun, E.; Elsbury, D.; Gautier, T., IV; Gomillion, S.; Hand, E.; Wilkins, A.

    2011-11-01

    We present the preliminary analysis of over 1739 known and 349 candidate Jovian Trojans observed by the NEOWISE component of the Wide-field Infrared Survey Explorer (WISE). With this survey the available diameters, albedos, and beaming parameters for the Jovian Trojans have been increased by more than an order of magnitude compared to previous surveys. We find that the Jovian Trojan population is very homogenous for sizes larger than ~10 km (close to the detection limit of WISE for these objects). The observed sample consists almost exclusively of low albedo objects, having a mean albedo value of 0.07 0.03. The beaming parameter was also derived for a large fraction of the observed sample, and it is also very homogenous with an observed mean value of 0.88 0.13. Preliminary debiasing of the survey shows that our observed sample is consistent with the leading cloud containing more objects than the trailing cloud. We estimate the fraction to be N(leading)/N(trailing) ~ 1.4 0.2, lower than the 1.6 0.1 value derived by Szab et al.

  3. WISE/NEOWISE OBSERVATIONS OF THE JOVIAN TROJANS: PRELIMINARY RESULTS

    SciTech Connect

    Grav, T.; Mainzer, A. K.; Bauer, J.; Masiero, J.; Eisenhardt, P. R. M.; Blauvelt, E.; DeBaun, E.; Elsbury, D.; Gautier, T. IV; Gomillion, S.; Hand, E.; Wilkins, A.; Spahr, T.; McMillan, R. S.; Walker, R.; Cutri, R.; Wright, E.

    2011-11-20

    We present the preliminary analysis of over 1739 known and 349 candidate Jovian Trojans observed by the NEOWISE component of the Wide-field Infrared Survey Explorer (WISE). With this survey the available diameters, albedos, and beaming parameters for the Jovian Trojans have been increased by more than an order of magnitude compared to previous surveys. We find that the Jovian Trojan population is very homogenous for sizes larger than {approx}10 km (close to the detection limit of WISE for these objects). The observed sample consists almost exclusively of low albedo objects, having a mean albedo value of 0.07 {+-} 0.03. The beaming parameter was also derived for a large fraction of the observed sample, and it is also very homogenous with an observed mean value of 0.88 {+-} 0.13. Preliminary debiasing of the survey shows that our observed sample is consistent with the leading cloud containing more objects than the trailing cloud. We estimate the fraction to be N(leading)/N(trailing) {approx} 1.4 {+-} 0.2, lower than the 1.6 {+-} 0.1 value derived by Szabo et al.

  4. Mars Science Laboratory relative humidity observations: Initial results

    NASA Astrophysics Data System (ADS)

    Harri, A.-M.; Genzer, M.; Kemppinen, O.; Gomez-Elvira, J.; Haberle, R.; Polkko, J.; Savijärvi, H.; Rennó, N.; Rodriguez-Manfredi, J. A.; Schmidt, W.; Richardson, M.; Siili, T.; Paton, M.; Torre-Juarez, M. De La; Mäkinen, T.; Newman, C.; Rafkin, S.; Mischna, M.; Merikallio, S.; Haukka, H.; Martin-Torres, J.; Komu, M.; Zorzano, M.-P.; Peinado, V.; Vazquez, L.; Urqui, R.

    2014-09-01

    The Mars Science Laboratory (MSL) made a successful landing at Gale crater early August 2012. MSL has an environmental instrument package called the Rover Environmental Monitoring Station (REMS) as a part of its scientific payload. REMS comprises instrumentation for the observation of atmospheric pressure, temperature of the air, ground temperature, wind speed and direction, relative humidity (REMS-H), and UV measurements. We concentrate on describing the REMS-H measurement performance and initial observations during the first 100 MSL sols as well as constraining the REMS-H results by comparing them with earlier observations and modeling results. The REMS-H device is based on polymeric capacitive humidity sensors developed by Vaisala Inc., and it makes use of transducer electronics section placed in the vicinity of the three humidity sensor heads. The humidity device is mounted on the REMS boom providing ventilation with the ambient atmosphere through a filter protecting the device from airborne dust. The final relative humidity results appear to be convincing and are aligned with earlier indirect observations of the total atmospheric precipitable water content. The water mixing ratio in the atmospheric surface layer appears to vary between 30 and 75 ppm. When assuming uniform mixing, the precipitable water content of the atmosphere is ranging from a few to six precipitable micrometers.

  5. Plasma observations near Jupiter - Initial results from Voyager 1

    NASA Technical Reports Server (NTRS)

    Bridge, H. S.; Belcher, J. W.; Lazarus, A. J.; Sullivan, J. D.; Mcnutt, R. L.; Bagenal, F.; Scudder, J. D.; Sittler, E. C.; Siscoe, G. L.; Vasyliunas, V. M.

    1979-01-01

    Extensive measurements of low-energy positive ions and electrons were made throughout the Jupiter encounter of Voyager 1. The bow shock and magnetopause were crossed several times at distances consistent with variations in the upstream solar wind pressure measured on Voyager 2. During the inbound pass, the number density increased by six orders of magnitude between the innermost magnetopause crossing at approximately 47 Jupiter radii and near closest approach at approximately 5 Jupiter radii; the plasma flow during this period was predominately in the direction of corotation. Marked increases in number density were observed twice per planetary rotation, near the magnetic equator. Jupiterward of the Io plasma torus, a cold, corotating plasma was observed and the energy/charge spectra show well-resolved, heavy-ion peaks at mass-to-charge ratios equal to 8, 16, 32, and 64.

  6. VLT observations of giant exoplanet atmospheres: reliability and new results

    NASA Astrophysics Data System (ADS)

    Lendl, M.; Delrez, L.; Gillon, M.; Madhusudhan, N.; Jehin, E.; Queloz, D.; Anderson, D. R.; Hellier, C.

    2015-10-01

    Transmission spectra obtained via multi-wavelength observations of transits are one of the most prominent pathways for the study of exoplanet atmospheres. We present results obtained with the ESO/VLT FORS2 instrument on the hot Saturn-mass exoplanet WASP-49b, based on three separate transit observations. FORS2 is known to produce substantial correlated noise due to inhomogeneous transparency of the telescope's linear atmospheric dispersion corrector. We account for theses systematics in a common way by using a common noise model approach. By using this approach together with low-order functions compensating for chromatic slopes, we obtain consistent results on the planetary transmission spectrum for all three dates. We do not identify any absorption signatures in the atmosphere of WASP-49b and thus conclude that this planet possesses hazes or clouds.

  7. Geodimeter measurements from Mishennaya Observatory: Analysis of observation results

    NASA Astrophysics Data System (ADS)

    Bakhtiarov, V. F.; Levin, V. E.; Saprykin, A. V.

    1992-02-01

    The data obtained by geodimeter measurements from the Mishennaya Observatory, city of Petropavlovsk-Kamchatsky, are presented. Temporal sequences of horizontal deformations along lines 7-50 km long, are analyzed for the period 1979-1989. A qualitative model for the relationship between an earthquake and deformations along the polygonal lines is proposed. The results of the statistical analysis of observation sequences are given.

  8. Plasma observations near saturn: initial results from voyager 2.

    PubMed

    Bridge, H S; Bagenal, F; Belcher, J W; Lazarus, A J; McNutt, R L; Sullivan, J D; Gazis, P R; Hartle, R E; Ogilvie, K W; Scudder, J D; Sittler, E C; Eviatar, A; Siscoe, G L; Goertz, C K; Vasyliunas, V M

    1982-01-29

    Results of measurements of plasma electrons and poitive ions made during the Voyager 2 encounter with Saturn have been combined with measurements from Voyager 1 and Pioneer 11 to define more clearly the configuration of plasma in the Saturnian magnetosphere. The general morphology is well represented by four regions: (i) the shocked solar wind plasma in the magnetosheath, observed between about 30 and 22 Saturn radii (RS) near the noon meridian; (ii) a variable density region between approximately 17 RS and the magnetopause; (iii) an extended thick plasma sheet between approximately 17 and approximately 7 RS symmetrical with respect to Saturn's equatorial plane and rotation axis; and (iv) an inner plasma torus that probably originates from local sources and extends inward from L approximately 7 to less than L approximately 2.7 (L is the magnetic shell parameter). In general, the heavy ions, probably O(+), are more closely confined to the equatorial plane than H(+), so that the ratio of heavy to light ions varies along the trajectory according to the distance of the spacecraft from the equatorial plane. The general configuration of the plasma sheet at Saturn found by Voyager 1 is confirmed, with some notable differences and additions. The "extended plasma sheet," observed between L approximately 7 and L approximately 15 by Voyager 1 is considerably thicker as observed by Voyager 2. Inward of L approximately 4, the plasma sheet collapses to a thin region about the equatorial plane. At the ring plane crossing, L approximately 2.7, the observations are consistent with a density of O(+) of approximately 100 per cubic centimeter, with a temperature of approximately 10 electron volts. The location of the bow shock and magnetopause crossings were consistent with those previously observed. The entire magnetosphere was larger during the outbound passage of Voyager 2 than had been previously observed; however, a magnetosphere of this size or larger is expected approximately 3 percent of the time. PMID:17771279

  9. Solar System Observations with Spitzer Space Telescope: Preliminary Results

    NASA Technical Reports Server (NTRS)

    Cruikshank, Dale P.

    2005-01-01

    The programs of observations of Solar System bodies conducted in the first year of the operation of the Spitzer Space Telescope as part of the Guaranteed Observing Time allocations are described. Initial results include the determination of the albedos of a number of Kuiper Belt objects and Centaurs from observations of their flux densities at 24 and 70 microns, and the detection of emission bands in the spectra of several distant asteroids (Trojans) around 10 and 25 microns. The 10 Kuiper Belt objects observed to date have albedos in the range 0.08 - 0.15, significantly higher than the earlier estimated 0.04. An additional KBO [(55565) 2002 AW(sub l97)] has an albedo of 0.17 plus or minus 0.03. The emission bands in the asteroid spectra are indicative of silicates, but specific minerals have not yet been identified. The Centaur/comet 29P/Schwassmann-Wachmann 1 has a nucleus surface albedo of 0.025 plus or minus 0.01, and its dust production rate was calculated from the properties of the coma. Several other investigations are in progress as the incoming data are processed and analyzed.

  10. First Results from NuSTAR Observations of Mkn 421

    NASA Technical Reports Server (NTRS)

    Balokovic, M.; Ajello, M.; Blandford, R. D.; Boggs, S. E.; Borracci, F.; Chiang, J.; Christensen, F. E.; Craig, W. W.; Forster, K.; Furniss, A.; Furst, F.; Ghisellini, G.; Giebels, B.; Giommi, P.; Grefenstette, B. W.; Hailey, C. J.; Harrison, F. A.; Hayashida, M.; Humensky, B.; Inoue, Y.; Koglin, J. E.; Krawczynski, H.; Madejski, G. M.; Madsen, K. K.; Meier, D. L.; Zhang, W. W.

    2013-01-01

    Mkn 421 is a nearby active galactic nucleus dominated at all wavelengths by a very broad nonthermal continuum thought to arise from a relativistic jet seen at a small angle to the line of sight. Its spectral energy distribution peaks in the X-ray and TeV gamma-ray bands, where the energy output is dominated by cooling of high-energy electrons in the jet. In order to study the electron distribution and its evolution, we carried out a dedicated multi-wavelength campaign, including extensive observations by the recently launched highly sensitive hard X-ray telescope NuSTAR, between December 2012 and May 2013. Here we present some intial results based on NuSTAR data from January through March 2013, as well as calibration observations conducted in 2012. Although the observations cover some of the faintest hard X-ray flux states ever observed for Mkn 421, the sensitivity is high enough to resolve intra-day spectral variability. We find that in this low state the dominant f ux variations are smooth on timescales of hours, with typical intra-hour variations of approximately less than 5%. We do not find evidence for either a cutoff in the hard X-ray spectrum, or a rise towards a high-energy component, but rather that at low flux the spectrum assumes a power law shape with a photon index of approximately 3. The spectrum is found to harden with increasing brightness.

  11. Plasma observations near Uranus - Initial results from Voyager 2

    NASA Technical Reports Server (NTRS)

    Bridge, H. S.; Belcher, J. W.; Coppi, B.; Lazarus, A. J.; Mcnutt, R. L., Jr.; Olbert, S.; Hartle, R. E.; Ogilvie, K. W.; Sittler, E. C., Jr.; Wolfe, R. S.

    1986-01-01

    The results of observations of the spatial distribution and physical properties of the space plasma near Uranus with instrumentation on board Voyager 2 are described. The data revealed the existence of a magnetosphere that held a warm component with a temperature of 4-50 eV and a peak density of 2 protons/cu cm and a hot component with a temperature of a few electron volts and a density of about 0.1 proton/cu cm. Only the warm component was observed within the L shell. The numerous crossings made of the plasma sheet in the magnetotail were at locations which suggested that the magnetotail has a geometric structure similar to that of the earth magnetotail. Finally, possible sources of the magnetospheric plasma particles are discussed.

  12. Plasma observations near Jupiter - Initial results from Voyager 2

    NASA Technical Reports Server (NTRS)

    Bridge, H. S.; Belcher, J. W.; Lazarus, A. J.; Sullivan, J. D.; Bagenal, F.; Mcnutt, R. L., Jr.; Ogilvie, K. W.; Scudder, J. D.; Sittler, E. D.; Vasyliunas, V. M.

    1979-01-01

    A preliminary report is presented of the results obtained by the Voyager 2 plasma experiment during the encounter of Voyager 2 with Jupiter from about 100 Jupiter radii before periapsis to about 300 Jupiter radii after periapsis, the instrument being identical to that on Voyager 1. The discussion covers the following: (1) the crossings of the bow shock and magnetopause observed on the inbound and outbound passes; (2) the radial variation of plasma properties in the magnetosphere; (3) variations in plasma properties near Ganymede; (4) corotation and composition of the plasma in the dayside magnetosphere; and (5) plasma sheet crossings observed on the inbound and outbound passes. From the planetary spin modulation of the plasma-electron intensity it is inferred that the plasma sheet is centered at the dipole magnetic equator out to a distance of 40-50 Jupiter radii and deviates from it toward the rotational equator at larger distances.

  13. Voyager spacecraft radio observations of Jupiter - Initial cruise results

    NASA Technical Reports Server (NTRS)

    Kaiser, M. L.; Desch, M. D.; Alexander, J. K.; Thieman, J. R.; Riddle, A. C.; Pearce, J. B.; Warwick, J. W.; Lecacheux, A.

    1979-01-01

    Low frequency (below 1326 kHz) observations of Jupiter obtained from November, 1977 through June, 1978 by the radio astronomy receivers carried by the two Voyager spacecraft are reported and compared with a large body of higher-frequency ground-based observations. Although the morphology of hectometric wavelength (HOM) emissions strongly resembles that of decametric (DAM) wavelength radio noise, they display opposite polarization. DAM emissions are strongly modulated by Io, whereas HOM emissions exhibit little or no influence from any satellite and appear to be modulated by the rotation phase of the planet. Several single-source models could possibly account for these results, including a model assuming emission at two well-separated frequencies above and below the local electron plasma frequency and the model proposed by Barbosa (1976) in which electrostatic waves at twice the upper hybrid frequency couple to both the ordinary and extraordinary electromagnetic modes. However, neither of these is entirely satisfactory.

  14. Magnetic field observations near Mercury: Preliminary results from Mariner 10

    NASA Technical Reports Server (NTRS)

    Ness, N. F.; Behannon, K. W.; Lepping, R. P.; Whang, Y. C.; Schatten, K. H.

    1974-01-01

    Results are presented from a preliminary analysis of data obtained near Mercury by the NASA/GSFC Magnetic Field Experiment on Mariner 10. A very well developed, detached bow shock wave, which developed as the super-Alfvenic solar wind interacted with the planet Mercury was observed. A magnetosphere-like region, with maximum field strength of 98 gamma at closest approach (704 km altitude) was also observed, and was contained within boundaries similar to the terrestrial magnetopause. The obstacle deflecting the solar wind flow was global in size, but the origin of the enhanced magnetic field was not established. The most plausible explanation, considering the complete body of data, favored the conclusion that Mercury has an intrinsic magnetic field.

  15. Energetic particles in supernova remnants: Results from VHE Observations

    NASA Astrophysics Data System (ADS)

    Slane, Patrick O.

    2016-01-01

    The rapidly-expanding ejecta in supernova remnants drive fast shocks in the surrounding medium. These shocks heat the ambient gas and create conditions suitable for the acceleration of charged particles to energies exceeding hundreds of TeV. These particles are believedto form the primary component of Galactic cosmic rays. The details of the acceleration process, including the need for amplified magnetic fields, the evidence for the presence of energetic hadrons, the process of particle escape, and the contributions from compressed and re-accelerated ambient cosmic rays are complex. Measurements across the electromagnetic spectrum are required to fully constrain the process, and observations of VHE gamma-rays from supernova remnants are particularly crucial. Here I will summarize current results from studies of particle acceleration in SNRs, with particular emphasis on the crucial constraints provided by the VHE observations.

  16. Mars Science Laboratory (MSL) - First Results of Relative Humidity Observations

    NASA Astrophysics Data System (ADS)

    Genzer, Maria; Harri, Ari-Matti; Kemppinen, Osku; Gmez-Elvira, Javier; Renno, Nilton; Savijrvi, Hannu; Schmidt, Walter; Polkko, Jouni; Rodrquez-Manfredi, Jose Antonio; de la Torre Jurez, Manuel; Mischna, Michael; Martn-Torres, Javier; Haukka, Harri; Paz Zorzano-Mier, Maria; Rafkin, Scott; Paton, Mark; MSL Science Team

    2013-04-01

    The Mars Science laboratory (MSL) called Curiosity made a successful landing at Gale crater early August 2012. MSL has an environmental instrument package called the Rover Environmental Monitoring Station (REMS) as a part of its scientific payload. REMS comprises instrumentation for the observation of atmospheric pressure, temperature of the air, ground temperature, wind speed and direction, relative humidity, and UV measurements. The REMS instrument suite is described at length in [1]. We concentrate on describing the first results from the REMS relative humidity observations and comparison of the measurements with modeling results. The REMS humidity device is provided by the Finnish Meteorological Institute. It is based on polymeric capacitive humidity sensors developed by Vaisala Inc. The humidity device makes use of one transducer electronics section placed in the vicinity of the three (3) humidity sensor heads. The humidity device is mounted on the REMS boom 2 providing ventilation with the ambient atmosphere through a filter protecting the device from airborne dust. The absolute accuracy of the humidity device is temperature dependent, and is of the order of 2% at the temperature range of -30 to -10 C, and of the order of 10% at the temperature range of -80 to -60 C. This enables the investigations of atmospheric humidity variations of both diurnal and seasonal scale. The humidity device measurements will have a lag, when a step-wise change in humidity is taking place. This lag effect is increasing with decreasing temperature, and it is of the order of a few hours at the temperature of -75 C. To compensate for the lag effect we used an algorithm developed by Mkinen [2]. The humidity observations were validated after tedious efforts. This was needed to compensate for the artifacts of the transducer electronics. The compensation process includes an assumption that the relative humidity at Mars in the temperature range of 0 to -30 C is about zero. The final relative humidity results appear to be convincing and are aligned with earlier observations of the total atmospheric precipitable water contents as well as with the modeling results. [3,4,5] References: [1] Gmez-Elvira J. et al. (2012), Space Sci. Rev. 170, 583-640. [2] Mkinen, T. (2012) Personal communication [3] Haberle, R.M. et al. (2013) Mars, submitted. [4] Smith, M. et al. (2006), J. Geophys. Res., 111, E12S13. [5] Savijarvi et al. (2010), Quart. J. Roy. Meteor. Soc., 136:651, 1497-1505.

  17. Plasma observations near Saturn - Initial results from Voyager 2

    NASA Technical Reports Server (NTRS)

    Bridge, H. S.; Bagenal, F.; Belcher, J. W.; Lazarus, A. J.; Mcnutt, R. L.; Sullivan, J. D.; Gazis, P. R.; Hartle, R. E.; Ogilvie, K. W.; Scudder, J. D.

    1982-01-01

    Results of plasma measurements made by Voyager 2 in the vicinity of Saturn are discussed and compared with those made by Pioneer 11 and Voyager 1 in a more limited range of latitudes. The initial bow shock crossing on the inbound trajectory closely agreed with the shock position inferred from the external ram pressure in the solar wind, although boundaries on the outbound pass were much further out than expected. Magnetospheric plasma observations reveal the presence of (1) shocked solar wind plasma in the magnetosheath between 30 and 22 Saturn radii; (2) a variable density region between 17 Saturn radii and the magnetopause; (3) an extended thick plasma sheet between 17 and 7 Saturn radii; and (4) an inner plasma torus probably originating from local sources. The ratio of heavy to light ions was observed to vary with distance to the equatorial plane in the dayside magnetosphere, with the heavy ions, probably O(+), more closely confined to the equatorial plane. The plasma data also account for the observed inner boundary of the neutral hydrogen torus discovered by Voyager 1.

  18. Results from the QUIET Q-Band Observing Season

    NASA Astrophysics Data System (ADS)

    Dumoulin, Robert Nicolas

    The Q/U Imaging ExperimenT (QUIET) is a ground-based telescope located in the high Atacama Desert in Chile, and is designed to measure the polarization of the Cosmic Microwave Background (CMB) in the Q and W frequency bands (43 and 95 GHz respectively) using coherent polarimeters. From 2008 October to 2010 December, data from more than 10,000 observing hours were collected, first with the Q-band receiver (2008 October to 2009 June) and then with the W-band receiver (until the end of the 2010 observing season). The QUIET data analysis effort uses two independent pipelines, one consisting of a maximum likelihood framework and the other consisting of a pseudo- Cℓ framework. Both pipelines employ blind analysis methods, and each provides analysis of the data using large suites of null tests specific to the pipeline. Analysis of the Q-band receiver data was completed in November of 2010, confirming the only previous detection of the first acoustic peak of the EE power spectrum and setting competitive limits on the scalar-to-tensor ratio, r. In this dissertation, the results from the Q-band observing season using the maximum likelihood pipeline will be presented.

  19. Magnetic Field Observations near Mercury: Preliminary Results from Mariner 10.

    PubMed

    Ness, N F; Behannon, K W; Lepping, R P; Whang, Y C; Schatten, K H

    1974-07-12

    Results are presented from a preliminary analysis of data obtained near Mercury on 29 March 1974 by the NASA-GSFC magnetic field experiment on Mariner 10. Rather unexpectedly, a very well-developed, detached bow shock wave, which develops as the super-Alfvénic solar wind interacts with the planet, has been observed. In addition, a magnetosphere-like region, with maximum field strength of 98 gammas at closest approach (704 kilometers altitude), has been observed, contained within boundaries similar to the terrestrial magnetopause. The obstacle deflecting the solar wind flow is global in size, but the origin of the enhanced magnetic field has not yet been uniquely established. The field may be intrinsic to the planet and distorted by interaction with the solar wind. It may also be associated with a complex induction process whereby the planetary interior-atmosphere-ionosphere interacts with the solar wind flow to generate the observed field by a dynamo action. The complete body of data favors the preliminary conclusion that Mercury has an intrinsic magnetic field. If this is correct, it represents a major scientific discovery in planetary magnetism and will have considerable impact on studies of the origin of the solar system. PMID:17810508

  20. HST Observations of the Uranian Ring Plane Crossing: Early Results

    NASA Astrophysics Data System (ADS)

    Showalter, Mark R.; Lissauer, J. J.; French, R. G.; Hamilton, D. P.; Nicholson, P. D.; de Pater, I.

    2007-10-01

    Between early May and mid-August 2007, Earth was on the north side of the Uranian ring plane while the Sun was still shining on the rings southern face. This has provided an exceedingly rare opportunity to view the ring system via transmitted light. The ? ring, which typically out-shines every other component of the inner ring-moon system, has been rendered essentially invisible. We have been conducting regular imaging of the Uranian system throughout this period with the Wide Field/Planetary Camera on HST to address numerous scientific goals. (1) To search the inner Uranian system for the "shepherding moons long believed to confine the narrow rings; (2) to study the packing density of the main rings via direct observations of their vertical thickness; (3) to search for the inner dust rings that appeared in a few Voyager images; (4) to determine the vertical thickness of the faint outer rings ? and ? (5) to obtain the most sensitive determinations of the outer rings colors and try to understand why ring ? is red but ring ? is blue; (6) to search for additional outer dust rings under optimal viewing geometry; and (7) to continue monitoring the seemingly chaotic orbital variations of the inner Uranian moons, particularly Mab. HST observations span mid-May to mid-September. We will present our initial results from this observing program.

  1. Electric earthquake precursors: from laboratory results to field observations

    NASA Astrophysics Data System (ADS)

    Vallianatos, Filippos; Triantis, Dimos; Tzanis, Andreas; Anastasiadis, Cimon; Stavrakas, Ilias

    The generation of transient electric potential prior to rupture has been demonstrated in a number of laboratory experiments involving both dry and wet rock specimens. Several different electrification effects are responsible for these observations, however, piezoelectricity cannot explain why quartz-free rocks can also generate precursory phenomena and electrokinetic phenomena are normally very weak to produce macro- and megascopic scale effects. Electrification is observed in dry, non-piezoelectric rocks meaning that additional, solid state mechanisms should be responsible. Herein we focus on a promising effect that is ubiquitous during brittle rock failure: the motion of charged edge dislocations (MCD) during crack opening and propagation (microfracturing). We report a series of laboratory experiments on dry marble samples and discuss their possible relationship to field observations of purported electric earthquake precursors (EEP). The experiments confirm the generation of pressure-stimulated currents (PSC) as expected by the MCD model. The PSC was linearly related to the stress rate, so long as the stressed material deformed elastically. Deviation from linearity arose when the applied stress drove the specimen into the plastic deformation range; this effect has been attributed to the dependence of the PSC on the stress rate and, ultimately, to the inverse of the changing (decreasing) Young's modulus. The emitted current appears very intense and non-linear just prior to failure, where massive crack propagation implies massive MCD processes. Repeated cycles of deformation are associated with progressively weaker current emission, indicating the strong dependence of electrification on the residual damage. Overall, the results are consistent with, and render support to the concept of electrification by MCD/microfracturing. Other mechanisms cannot be excluded of course but are rather considered to accompany and supplement the drastic MCD process. The experiments cannot determine whether these process can scale up to earthquake-size volumes but they certainly do not contest the possibility. If so, the origin of the EEP would be massive crack formation and propagation, which in the case of earthquakes is expected to be a short-lived process at the terminal phase of the cycle. Observable macroscopic ULF field would be generated by the superposition of fields generated by multiple simultaneous individual cracks and would evolve in correspondence with the crack propagation process. It is possible to model the evolution of large crack ensembles and assess the expected time functions of transient EEP events: the result is a family of asymmetric-bell shaped time functions that may appear isolated or in groups. The model has been successfully applied to the analysis of real field observations.

  2. First results from the Comet ISON Observing Campaign (CIOC)

    NASA Astrophysics Data System (ADS)

    Lisse, C.

    2014-07-01

    Comet ISON came fresh from the Oort Cloud as predicted, coming within 0.07 au of Mars, 0.24 au of Mercury, and 10^{6} km of the solar photospheric surface. It did not become the ''Comet of the Century'' in terms of its brightness in the Earth's night-time sky as predicted, but instead became one of the rare dynamically new Oort Cloud comets to graze the Sun's corona (these occur every few decades; the last one observed was C/Ikeya-Seki 1965). For an initially bright comet detected as far out as the orbit of Saturn in Sept 2011, the comet worried us all quite a bit with its flat-lining activity from 4 to 0.8 au (March to Oct 2013). It thus put on a somewhat disappointing showing at Mars in early October, but then defied predictions of its demise and a government shutdown, ramping up instead to become a beautiful early morning green ''lollipop'' as it passed Mercury in mid-November (Figure). ISON ultimately peaked at maximum Q_{gas} = 2 × 10^{30} mol/s of water [1] within the last few days before perihelion, then seemed to have almost no gas output the day of perihelion, 28 Nov 2013 [2] before spectacularly disrupting under the watchful eyes of the SOHO and STEREO spacecraft (Figure), after which its debris fan was tracked for days until it finally disappeared [3,4]. Over 19 NASA and ESA spacecraft ultimately pointed at the comet, with at least 14 reporting detections of it ranging from the X-rays through the infrared. More than 30 ground-based observatories observed ISON from at UV to radio wavelengths. Important findings concerning the comet's size, rotation state, dust to gas ratio, composition, and coma and tail structure were made during ISON'S apparition. Numerous observing groups produced evidence for a small and CO poor (but rich in solid carbon and CO_2) nucleus that was rapidly evolving. Throughout this time, parallels to the behavior of other dynamically new comets, like C/1973 E (Kohoutek), were readily apparent. In this talk I present an overview of the observational findings for ISON.

  3. Recent results from hadronic observables at the CERN SPS

    SciTech Connect

    Jacobs, P.M.; NA49 Collaboration

    1996-10-01

    Some recent results on Pb+Pb collisions from NA44 and NA49 at the CERN SPS are reviewed and compared to collisions of lighter systems and lower energies. For central collisions: primordial protons show enhanced stopping for Pb+Pb relative to S+S at the same energy, but less stopping than heavy systems at lower energy; yields of negative hadrons, kaons and lambdas scale with the number of participants relative to S+S; and transverse momentum spectra show strong evidence for enhanced radial flow in the heaviest system. For intermediate impact parameters, significant quadrupole deformation of the transverse energy distribution is seen at mid-rapidity. Coulomb effects are seen for central collisions in the ratio of yields {pi}{sup -}/{pi}{sup +} and unlike-sign two particle correlations.

  4. DUst around NEarby Stars. The Survey Observational Results

    NASA Technical Reports Server (NTRS)

    Eiroa, C.; Marshall, J. P.; Mora, A.; Montesinos, B.; Absil, O.; Augereau, J. Ch.; Bayo, A.; Bryden, G.; Danchi, W.; delBurgo, C.; Ertel, S..; Fridlund, M.; Heras, A. M.; Krivov, A. V.; Launhardt, R.; Liseau, R.; Lohne, T.; Maldonado, J.; Pilbratt, G. L.; Roberge, A.; Rodman, J.; Sanz-Forcada, J.; Stapelfeldt, K.; Ardila, D.; Beichmann, C.

    2013-01-01

    Context. Debris discs are a consequence of the planet formation process and constitute the fingerprints of planetesimal systems. Their solar system counterparts are the asteroid and Edgeworth-Kuiper belts.Aims. The DUNES survey aims at detecting extra-solar analogues to the Edgeworth-Kuiper belt around solar-type stars, putting in this way the solar system into context. The survey allows us to address some questions related to the prevalence and properties of planetesimal systems.Methods. We used Herschel PACS to observe a sample of nearby FGK stars. Data at 100 and 160 micron were obtained, complemented in some cases with observations at 70 micron, and at 250, 350 and 500 micron using SPIRE. The observing strategy was to integrate as deep as possible at 100 micron to detect the stellar photosphere. Results. Debris discs have been detected at a fractional luminosity level down to several times that of the Edgeworth-Kuiper belt. The incidence rate of discs around the DUNES stars is increased from a rate of approx. 12.1% +/- 5% before Herschel to approx 20.2 % +/- % 2. A significant fraction (approx. 52%) of the discs are resolved, which represents an enormous step ahead from the previously known resolved discs. Some stars are associated with faint far-IR excesses attributed to a new class of cold discs. Although it cannot be excluded that these excesses are produced by coincidental alignment of background galaxies, statistical arguments suggest that at least some of them are true debris discs. Some discs display peculiar SEDs with spectral indexes in the 70-160 micron range steeper than the Rayleigh-Jeans one. An analysis of the debris disc parameters suggests that a decrease might exist of the mean black body radius from the F-type to the K-type stars. In addition, a weak trend is suggested for a correlation of disc sizes and an anticorrelation of disc temperatures with the stellar age.

  5. Spacelab Science Results Study. Volume 1; External Observations

    NASA Technical Reports Server (NTRS)

    Naumann, Robert J. (Compiler)

    1999-01-01

    Some of the 36 Spacelab missions were more or less dedicated to specific scientific disciplines, while other carried a eclectic mixture of experiments ranging from astrophysics to life sciences. However, the experiments can be logically classified into two general categories; those that make use of the Shuttle as an observing platform for external phenomena (including those which use the Shuttle in an interactive mode) and those which use the Shuttle as a microgravity laboratory. This first volume of this Spacelab Science Results study will be devoted to experiments of the first category. The disciplines included are Astrophysics, Solar Physics, Space Plasma Physics, Atmospheric Sciences, and Earth Sciences. Because of the large number of microgravity investigations, Volume 2 will be devoted to Microgravity Sciences, which includes Fluid Physics, Combustion Science, Materials Science, and Biotechnology, and Volume 3 will be devoted to Space Life Sciences, which studies the response and adaptability of living organisms to the microgravity environment.

  6. Mars Global Surveyor TES Results: Observations of Water Ice Clouds

    NASA Technical Reports Server (NTRS)

    Pearl, John C.; Smith, M. D.; Conrath, B. J.; Bandfield, J. L.; Christensen, P. R.

    1999-01-01

    On July 31, 1999, Mars Global Surveyor completed its first martian year in orbit. During this time, the Thermal Emission Spectrometer (TES) experiment gathered extensive data on water ice clouds. We report here on three types of martian clouds. 1) Martian southern summer has long been characterized as the season when the most severe dust storms occur. It is now apparent that northern spring/summer is characterized as a time of substantial low latitude ice clouds [1]. TES observations beginning in the northern summer (Lsubs=107) show a well developed cloud belt between 10S and 30N latitude; 12 micron opacities were typically 0.15. This system decreased dramatically after Lsubs= 130. Thereafter, remnants were most persistent over the Tharsis ridge. 2) Clouds associated with major orographic features follow a different pattern [2]. Clouds of this type were present prior to the regional Noachis dust storm of 1997. They disappeared with the onset of the storm, but reappeared rather quickly following its decay. Typical infrared opacities were near 0.5. 3) Extensive, very thin clouds are also widespread [3]. Found at high altitudes (above 35 km), their opacities are typically a few hundredths. At times, such as in northern spring, these clouds are limited in their northern extent only by the southern edge of the polar vortex. We describe the distribution, infrared optical properties, and seasonal trends of these systems during the first martian year of TES operations.

  7. Tajikistan fireball network and results of photographic observations

    NASA Astrophysics Data System (ADS)

    Kokhirova, G. I.; Babadzhanov, P. B.; Khamroev, U. Kh.

    2015-07-01

    The fireball network was created in Tajikistan with the aim of obtaining new data on the near-Earth meteoroid environment concerning large bodies, entering in the Earth's atmosphere and producing fireballs, as well as new observational data on the activity of known meteor/fireball showers. The network consists of five observational stations equipped with the photographic fireball and digital all-sky cameras. Distances between the stations are from 53 to 184 km and the area covered by monitoring is around 11000 km2. For astrometric reduction of fireball photographs, a technique has been developed that allows positions of object details to be determined at an accuracy of about 1', which is a sufficiently good result for negatives of this scale. In the method of photometric reduction, a dependence of measured widths of diurnal star trails on their magnitudes is used. As a result of processing of multi-station photographs of more than 200 fireballs, photographed by the fireball network for 2006-2013, the data on their atmospheric trajectories, coordinates of radiants, velocities, decelerations, orbits in the interplanetary space, light curves, photometric masses, and densities, as well as on the nature of origin of meteoroids which produced the fireballs are obtained; membership of the fireballs to the known fireball/meteor showers is determined. A brightness of the majority of fireballs is within the maximum absolute magnitude range from -5 to -8. It is shown that 62% of fireball-producing meteoroids have a cometary origin and the remaining 38% are of an asteroidal nature. The greater part of the photographed fireballs belongs to the known meteor/fireball showers, while the lesser part (almost 30%) relates to the sporadic background. The obtained results will noticeably replenish the world database with new information on fireballs and are required for solving contemporary astronomy problems associated with studying meteoroid environment in the near-Earth space and the asteroidal-cometary hazard as well as for discovering genetic links between small bodies of the Solar System.

  8. Earth observations and photography experiment: Summary of significant results

    NASA Technical Reports Server (NTRS)

    El-Baz, F.

    1978-01-01

    Observation and photographic data from the Apollo Soyuz Test Project are analyzed. The discussion is structured according to the fields of investigation including: geology, desert studies, oceanography, hydrology, and meteorology. The data were obtained by: (1) visual observations of selected Earth features, (2) hand-held camera photography to document observations, and (3) stereo mapping photography of areas of significant scientific interest.

  9. Healthy Older Observers Show Equivalent Perceptual-Cognitive Training Benefits to Young Adults for Multiple Object Tracking

    PubMed Central

    Legault, Isabelle; Allard, Rmy; Faubert, Jocelyn

    2013-01-01

    The capacity to process complex dynamic scenes is of critical importance in real life. For instance, traveling through a crowd while avoiding collisions and maintaining orientation and good motor control requires fluent and continuous perceptual-cognitive processing. It is well documented that effects of healthy aging can influence perceptual-cognitive processes (Faubert, 2002) and that the efficiency of such processes can improve with training even for older adults (Richards et al., 2006). Here we assess the capacity of older participants to improve their tracking speed thresholds in a dynamic, virtual reality environment. Results show that this capacity is significantly affected by healthy aging but that perceptual-cognitive training can significantly reduce age-related effects in older individuals, who show an identical learning function to younger healthy adults. Data support the notion that learning in healthy older persons is maintained for processing complex dynamic scenes. PMID:23761025

  10. Cassini CIRS: Early Results from Saturn Orbit Insertion Ring Observations

    NASA Astrophysics Data System (ADS)

    Spilker, L. J.; Pilorz, S. H.; Ferrari, C.; Wallis, B. D.; Flasar, F. M.; Pearl, J. C.; Showalter, M. R.; Brooks, S. M.; Edgington, S. G.; Achterberg, R. K.; Nixon, C. A.; Cassini CIRS

    2004-11-01

    The Cassini Composite Infrared Spectrometer (CIRS) obtained thermal spectra of the rings during Saturn orbit insertion (SOI). CIRS is a Fourier-transform spectrometer that measures radiation in the thermal infrared from 7 microns to 1 millimeter (1400 to 10 cm-1). For 65 minutes immediately following the SOI burn, the spacecraft flew over the unilluminated side of the main rings and was nearly an order of magnitude closer to the rings than it will be at any other time in the mission. CIRS obtained a scan of segments of the main rings at an average spatial resolution of 200 km with a spectral resolution of 15.5 cm-1. Following the outbound ring plane crossing, CIRS obtained a single scan of a portion of the lit A ring. CIRS retrieved temperatures for the unlit side of Saturn's rings from the SOI scan. Temperatures varied from approximately 70 K to 110 K. The data show that opaque sections of the rings, like the A and B rings, are cooler than the more transparent sections, like the Cassini Division and C ring. Distinct cool and warm regions are also present in the C ring and Cassini Division, with the cool regions corresponding to the more optically thick ringlets. CIRS observed the lit A ring at a phase angle of 130 degrees and the unlit A ring at 60 degrees phase. In this case, for very different phase angles, the retrieved lit and unlit A ring temperatures appear comparable, providing new evidence for possible slowly rotating particles. Preliminary information on retrieved temperatures and ring characteristics will be reported. This work was performed at JPL under contract with NASA and at CEA Saclay supported by the "Programme National de Planetologie".

  11. International program of observations of selected minor planets: first results

    NASA Astrophysics Data System (ADS)

    Chernetenko, Yulia A.

    2001-07-01

    International programs of observations of selected minor planets have lasted about 50 years and the last one comes to the end in 2000. The main aim of these observational programs consists in obtaining the orientation of the stellar reference frame with respect to the dynamical one using observations of the bright minor planets. The observations are also useful for the orbital improvements of the asteroids themselves. They are available from the author via e-mail at the address . During the above mentioned period more than 23 000 observations of minor planets, referred to different reference star catalogues, have been obtained. The reduction procedure of observations to the PPM star catalogue is described. The orientation parameters are given and discussed.

  12. New results of the spectral observations of CP stars

    NASA Astrophysics Data System (ADS)

    Polosukhina, N. S.; Shavrina, A. V.; Drake, N. A.; Kudryavtsev, D. O.; Smirnova, M. A.

    2010-04-01

    The lithium problem in Ap-CP stars has been, for a long time, a subject of debate. Individual characteristics of CP stars, such as high abundance of the rare-earth elements presence of magnetic fields, complicate structure of the surface distribution of chemical elements, rapid oscillations of some CP-stars, make the detection of the lithium lines and the determination of the lithium abundance, a difficult task. During the International Meeting in Slovakia in 1996, the lithium problem in Ap-CP stars was discussed. The results of the Li study carried out in CrAO Polosukhina (1973-1976), the works of Hack & Faraggiana (1963), Wallerstein & Hack (1964), Faraggiana et al. (1992-1996) formed the basis of the International project Lithium in the cool CP-stars with magnetic fields. The main goal of the project was, using systematical observations of Ap-CP stars with phase rotation in the spectral regions of the resonance doublet Li I 6708 and subordinate 6104 lithium lines with different telescopes, to create a database, which will permit to explain the physical origin of anomalous Li abundance in the atmospheres of these stars.

  13. [LINKOR: results of observational program in patients with myocardial infarction].

    PubMed

    Glezer, M G

    2013-01-01

    The results of Assessment Program effective treatment of patients with myocardiaL INfarction drug ProCORalan (ivabradine) in outpatient practice, conducted in 53 cities of the Russian Federation, 333 doctors. Included 1226 patients (822 men and 404 women, average age 60,1+/-9,3 years). Despite treatment, before inclusion in the patients maintained an average 8,17+/-8,60 (mediana 6) angina attacks per week, elevated blood pressure (141,8+/-20,3/86,2+/-11,6 mm Hg) and heart rate (84,5 +/-10,4 beats / min). Adding to ivabradine treatment for 16 weeks resulted in significant (p<0.00001) reduction in heart rate (up to 63,1+/-7,5 beats / min), the number of angina attacks per week (from 8.17 to 1.27) and need for nitroglycerin (from 7.69 to 0.89 tablets per week). Decreased the number of patients that called ambulance assistance (from 35.6 to 1.5%), and hospitalization (from 15.4 to 1.2%). There was a significant (p<0.00001) increase in evaluating the effectiveness of treatment (from 5,4+/-1,8 to 8,9 +/-1,3 points), reducing the risk stratification of patients (6,1+/-1,5 to 4 3+/-2,0 points), increased stability evaluation of state (from 5,6+/-1,9 to 3,7+/-2,2 points) and improved assessment of prognosis (from 5,7+/-2,0 to 3,6 +/-1,9 points). Expressed significantly positive effects observed after 1 month of therapy, after the effect became more pronounced. Significantly improved quality of life estimated by Seattle Angina Questionnaire and Minnesota Living with Heart Failure. The maximum recommended dose ivabradine of 15mg/day were given 50% of the patients, the dose of 10 mg/day - 28%. Adverse effects were reported in 3.3% of patients, of which, according to doctors associated with taking the drug - 0.82%. During follow up, 4 patients died. Thus, the addition of ivabradine to -blocker therapy, persons with a history of myocardial infarction and angina experiencing elevated heart rate, are the tactics of a rational and safe therapy. PMID:23952999

  14. Initial Results from the Circumarctic Lakes Observation Network (CALON) Project

    NASA Astrophysics Data System (ADS)

    Hinkel, K. M.; Lenters, J. D.; Grosse, G.; Arp, C. D.; Jones, B.; Beck, R. A.; Eisner, W. R.; Frey, K. E.; Liu, H.; Kim, C.; Townsend-Small, A.

    2011-12-01

    About half of the Arctic Coastal Plain (ACP) of northern Alaska is covered with thermokarst lakes and drained lake basins, making lakes a dominant landscape element and a crucial component of the Arctic permafrost system. However, to date there has been no systematic collection of key lake parameters or baseline data with which to make spatial and temporal comparisons to assess the impact of warmer temperatures, changing cloud cover and precipitation patterns, permafrost degradation, and direct human impacts on lakes. As separate groups, we have been working on lakes in arctic Alaska for the past decade and are currently monitoring some lakes. This effort has recently been organized into the Circumarctic Lakes Observation Network (CALON) with funding from NSF's Arctic Observing Network (AON) program. The objective of CALON is to expand and integrate our existing lake monitoring network across arctic Alaska to provide data for key indices using in situ measurements, field surveys, interviews with members of the indigenous community, and remote sensing/GIS technologies. In 2012, we will enhance the existing in situ network by developing lake monitoring sites to collect year-round baseline data and assess physical, chemical, and biological lake characteristics across environmental gradients. This will be accomplished by implementing a multiscale (hierarchical) lake instrumentation scheme such that basic data are collected from 51 lakes, while a subset of 16 lakes is more intensively instrumented. Regional scaling and extrapolation of key metrics is accomplished through validation of satellite imagery with ground measurements, and standardized protocols will be developed to enable inter-site comparison and to prepare for expansion towards a pan-Arctic network. Initial results are available from lake water profile temperature measurements made in summer 2010 along a 130-km transect extending from Barrow southward toward the interior. Ice-out occurs about 2-4 weeks later on lakes near the Arctic coast, reflecting the marine influence. Rapid warming follows ice-cover decay, with water temperature responding synchronously to daily and synoptic weather variations across the area. Inland lakes are significantly (6C) warmer in mid-summer than those near the coast, which is also in accordance with the regional climatic gradient. All lakes are well-mixed and largely isothermal, with minimal thermal stratification (< 2C) occurring only during calm, sunny periods in deeper lakes (> 2m). During the last several years lake water temperature, water level, and ice thickness measurements have also been collected from in a number of lakes located near a coastal hub site in the vicinity of Teshekpuk Lake. This dataset also reveals variability in the thermal regime over small geographic areas both within and between years with respect to differences in lake depth, lake size, and local environmental conditions.

  15. Plasma observations near Neptune: Initial results for Voyager 2

    SciTech Connect

    Belcher, J.W.; Bridge, H.S.; Coppi, B.; Gordon, G.S. Jr.; Lazarus, A.J.; McNutt, R.L. Jr.; Richardson, J.D.; Steinberg, J.T.; Sullivan, A.; Szabo, A.; Villanueva, L.; Zhang, M. ); Bagenal, F. ); Divers, O. ); Ogilvie, K.W.; Sittler, E.C. Jr. ); Siscoe, G.L. ); Eviatar, A. ); Vasyliunas, V.M. )

    1989-12-15

    The plasma science experiment on Voyager 2 made observations of the plasma environment in Neptune's magnetosphere and in the surrounding solar wind. Because of the large tilt of the magnetic dipole and fortuitous timing, Voyager entered Neptune's magnetosphere through the cusp region, the first cusp observations at an outer planet. Thus the transition from the magnetosheath to the magnetosphere observed by Voyager 2 was not sharp but rather appeared as a gradual decrease in plasma density and temperature. The maximum plasma density observed in the magnetosphere is inferred to be 1.4 per cubic centimeter (the exact value depends on the composition), the smallest observed by Voyager in any magnetosphere. The plasma has at least two components; light ions (mass, 1 to 5) and heavy ions (mass, 10 to 40), but more precise species identification is not yet available. Most of the plasma is concentrated in a plasma sheet or plasma torus and near closest approach to the planet. A likely source of the heavy ions is Triton's atmosphere or ionosphere, whereas the light ions probably escape from Neptune. The large tilt of Neptune's magnetic dipole produces a dynamic magnetosphere that changes configuration every 16 hours as the planet rotates.

  16. Plasma observations near neptune: initial results from voyager 2.

    PubMed

    Belcher, J W; Bridge, H S; Bagenal, F; Coppi, B; Divers, O; Eviatar, A; Gordon, G S; Lazarus, A J; McNutt, R L; Ogilvie, K W; Richardson, J D; Siscoe, G L; Sittler, E C; Steinberg, J T; Sullivan, J D; Szabo, A; Villanueva, L; Vasyliunas, V M; Zhang, M

    1989-12-15

    The plasma science experiment on Voyager 2 made observations of the plasma environment in Neptune's magnetosphere and in the surrounding solar wind. Because of the large tilt of the magnetic dipole and fortuitous timing, Voyager entered Neptune's magnetosphere through the cusp region, the first cusp observations at an outer planet. Thus the transition from the magnetosheath to the magnetosphere observed by Voyager 2 was not sharp but rather appeared as a gradual decrease in plasma density and temperature. The maximum plasma density observed in the magnetosphere is inferred to be 1.4 per cubic centimeter (the exact value depends on the composition), the smallest observed by Voyager in any magnetosphere. The plasma has at least two components; light ions (mass, 1 to 5) and heavy ions (mass, 10 to 40), but more precise species identification is not yet available. Most of the plasma is concentrated in a plasma sheet or plasma torus and near closest approach to the planet. A likely source of the heavy ions is Triton's atmosphere or ionosphere, whereas the light ions probably escape from Neptune. The large tilt of Neptune's magnetic dipole produces a dynamic magnetosphere that changes configuration every 16 hours as the planet rotates. PMID:17756003

  17. Plasma observations near Neptune - Initial results from Voyager 2

    NASA Technical Reports Server (NTRS)

    Belcher, J. W.; Bridge, H. S.; Coppi, B.; Gordon, G. S., Jr.; Lazarus, A. J.; Mcnutt, R. L., Jr.; Bagenal, F.; Divers, O.; Eviatar, A.; Ogilvie, K. W.

    1989-01-01

    The plasma science experiment on Voyager 2 made observations of the plasma environment in Neptune's magnetosphere and in the surrounding solar wind. Because of the large tilt of the magnetic dipole and fortuitous timing, Voyager entered Neptune's magnetosphere through the cusp region, the first cusp observations at an outer planet. Thus the transition from the magnetosheath to the magnetosphere observed by Voyager 2 was not sharp but rather appeared as a gradual decrease in plasma density and temperature. The maximum plasma density observed in the magnetosphere is inferred to be 1.4 per cubic centimeter (the exact value depends on the composition), the smallest observed by Voyager in any magnetosphere. The plasma has at least two components; light ions (mass, 1 to 5) and heavy ions (mass, 10 to 40), but more precise species identification is not yet available. Most of the plasma is concentrated in a plasma sheet or plasma torus and near closest approach to the planet. A likely source of the heavy ions is Triton's atmosphere or ionosphere, whereas the light ions probably escape from Neptune. The large tilt of Neptune's magnetic dipole produces a dynamic magnetosphere that changes configuration every 16 hours as the planet rotates.

  18. Infrasound/seismic observation of the Hayabusa reentry: Observations and preliminary results

    NASA Astrophysics Data System (ADS)

    Ishihara, Yoshiaki; Hiramatsu, Yoshihiro; Yamamoto, Masa-yuki; Furumoto, Muneyoshi; Fujita, Kazuhisa

    2012-07-01

    The Hayabusa, the world's first sample-return minor body explorer, returned to the Earth, and reentered the Earth's atmosphere on June 13, 2010. Multi-site ground observations of the Hayabusa reentry were carried out in the Woomera Prohibited Area (WPA), Australia. The ground observations were configured with optical imaging with still and video recordings, spectroscopies, and shockwave detection with infrasound and seismic sensors. At three main stations, we installed small aperture infrasound/seismic arrays, as well as three single component seismic sub stations. The infrasound and seismic sensors clearly recorded sonic-boom-type shockwaves from the Hayabusa Sample Return Capsule (H-SRC) and the disrupted fragments of the Hayabusa Spacecraft (H-S/C) itself. Positive overpressure values of shockwaves (corresponding to the H-SRC) recorded at the three main stations were 1.3 Pa, 1.0 Pa, and 0.7 Pa with slant distances of 36.9 km, 54.9 km, and 67.8 km, respectively. Incident vectors of the shockwave from the H-SRC at all three arrays are estimated by an F-K spectrum and agree well with those predicted. Particle motions of ground motions excited by the shockwave show characteristics of a typical Rayleigh wave.

  19. Cassini Observations of Saturn's Magnetotail Region: Preliminary Results

    NASA Technical Reports Server (NTRS)

    Sittler, E. C.; Arridge, C.; Rymer, A.; Coates, A.; Krupp, N.; Blanc, M.; Richardson, J.; Andre, N.; Thomsen, M.; Tokar, R. L.; McAndrews, H. J.; Henderson, Mike; Cooper, J. F.; Burger, M.; Simpson, D.; Khurana, K. K.; Russell, C.; Dougherty, M.; Young, D. T.

    2007-01-01

    Using Cassini thermal plasma, hot plasma and magnetic field observations for several intervals between the dawn meridian of Saturn's outer magnetosphere and Saturn's magnetotail region, we investigate the structure of the magnetotail, plasma and magnetic field properties within tail-like current sheet regions and ion flows within the magnetotail regions. We use Cassini Plasma Spectrometer (CAPS) Ion Mass Spectrometer (IMS), Electron Plasma Spectrometer (ELS) observations, MIMI LEMMS ion and electron observations and Cassini magnetometer data (MAG) to characterize the plasma environment. IMS observations are used to measure plasma flow velocities from which one can infer rotation versus convective flows. IMS composition measurements are used to trace the source of plasma from the inner magnetosphere (protons, H2+ and water group ions) versus an external solar wind source (protons and e +i+on s). A critical parameter for both models is the strength of the convection electric field with respect to the rotational electric field for the large scale magnetosphere. For example, are there significant return flows (i.e., negative radial velocities, VR < 0) and/or plasmoids (V(sub R) > 0) within the magnetotail region? Initial preliminary evidence of such out flows and return flows was presented by Sittler et al. This talk complements the more global analysis by McAndrews et al.

  20. Cassini Observations of Saturn's Dawn-Magnetotail Region: Preliminary Results

    NASA Technical Reports Server (NTRS)

    Sittler, Edward C.

    2007-01-01

    Using Cassini thermal plasma, hot plasma and magnetic field observations for several intervals between the dawn meridian of Saturn's outer magnetosphere and Saturn's magnetotail region, we investigate the structure of the magnetotail, plasma and magnetic field properties within tail-like current sheet regions and ion flows within the dawn to magnetotail regions. We use Cassini Plasma Spectrometer (CAPS) Ion Mass Spectrometer (IMS) and Electron Plasma Spectrometer (ELS) observations and MIMI LEMMS ion and electron observations to characterize the plasma environment. LMS observations are used to measure plasma flow velocities from which one can infer rotation versus convective flows. IMS composition measurements are used to trace the, source of plasma from the inner magnetosphere (protons, H(2+) and water group ions) versus an external solar wind source (protons and He++ ions). A critical parameter for both models is the strength of the convection electric field with respect to the rotational electric field for the large scale magnetosphere. For example, are there significant return flows (i.e., negative radial velocities, V(sub R) < 0) and/or plasmoids (V(sub R) > 0) within the magnetotail region?

  1. Sensor Web Interoperability Testbed Results Incorporating Earth Observation Satellites

    NASA Technical Reports Server (NTRS)

    Frye, Stuart; Mandl, Daniel J.; Alameh, Nadine; Bambacus, Myra; Cappelaere, Pat; Falke, Stefan; Derezinski, Linda; Zhao, Piesheng

    2007-01-01

    This paper describes an Earth Observation Sensor Web scenario based on the Open Geospatial Consortium s Sensor Web Enablement and Web Services interoperability standards. The scenario demonstrates the application of standards in describing, discovering, accessing and tasking satellites and groundbased sensor installations in a sequence of analysis activities that deliver information required by decision makers in response to national, regional or local emergencies.

  2. Crustal dynamics project observations: 1982 results and plans for 1983

    NASA Technical Reports Server (NTRS)

    Frey, H.

    1983-01-01

    The 1982 Crustal Dynamics Project observations by fixed and mobile SLR and VLBI systems are reviewed. Plate motion measurements between North America and Europe were conducted by both techniques and SLR measurements were also made between North America, the Pacific, Australia and South American plates. Regional deformation measurements by VLBI and SLR systems were restricted to the western United States in 1982, including a number of important intercomparison baseline measured by both techniques. In 1983 the observing program grows significantly, with new SLR systems in Mexico, Easter Island, the Pacific and Italy. New VLBI systems will include a dedicated VLBI site at Weltzell, in Germany. Two highly mobile SLR and two highly mobile VLBI systems will greatly increase the regional deformation measurements in California and through the Basin and Range, where more than 25 sites will be occupied in 1983.

  3. Voyager spacecraft radio observations of Jupiter: Initial cruise results

    NASA Technical Reports Server (NTRS)

    Kaiser, M. L.; Desch, M. D.; Riddle, A. C.; Lecacheux, A.; Pearce, J. B.; Alexander, J. K.; Warwick, J. W.; Thieman, J. R.

    1979-01-01

    Jupiter's low-frequency radio emission were detected by the planetary radio astronomy instruments onboard the two Voyager spacecraft. The emission is surprisingly similar in morphology but opposite in polarization to the high-frequency Jovian radio noise that were observed with ground-based telescopes for more than two decades. Several possible explanations for the behavior of the low-frequency emission are examined, but none of them is completely satisfactory.

  4. Initial Pioneer Venus magnetic field results - Dayside observations

    NASA Technical Reports Server (NTRS)

    Russell, C. T.; Elphic, R. C.; Slavin, J. A.

    1979-01-01

    Pioneer Venus magnetometer observations in the sunlit ionosphere indicate that the ionosphere is dynamic and very responsive to external solar wind conditions. Bow shock location, ionosphere location, the strength of the magnetic field just outside the ionopause, and the field strength in the ionosphere are found to be variable, and the properties of flux ropes in the ionospheric magnetic field are considered. Data on magnetic energy density and on magnetic field strength are presented.

  5. WISE/NEOWISE OBSERVATIONS OF THE HILDA POPULATION: PRELIMINARY RESULTS

    SciTech Connect

    Grav, T.; Mainzer, A. K.; Bauer, J.; Masiero, J.; Eisenhardt, P. R.; Blauvelt, E.; DeBaun, E.; Elsbury, D.; Gautier, T.; Gomillion, S.; Hand, E.; Wilkins, A.; Spahr, T.; McMillan, R. S.; Walker, R.; Cutri, R.; Wright, E.

    2012-01-10

    We present the preliminary analysis of 1023 known asteroids in the Hilda region of the solar system observed by the NEOWISE component of the Wide-field Infrared Survey Explorer (WISE). The sizes of the Hildas observed range from {approx}3 to 200 km. We find no size-albedo dependency as reported by other projects. The albedos of our sample are low, with a weighted mean value of p{sub V} = 0.055 {+-} 0.018, for all sizes sampled by the NEOWISE survey. We observed a significant fraction of the objects in the two known collisional families in the Hilda population. It is found that the Hilda collisional family is brighter, with a weighted mean albedo of p{sub V} = 0.061 {+-} 0.011, than the general population and dominated by D-type asteroids, while the Schubart collisional family is darker, with a weighted mean albedo of p{sub V} = 0.039 {+-} 0.013. Using the reflected sunlight in the two shortest WISE bandpasses, we are able to derive a method for taxonomic classification of {approx}10% of the Hildas detected in the NEOWISE survey. For the Hildas with diameter larger than 30 km, there are 67{sup +7}{sub -15}% D-type asteroids and 26{sup +17}{sub -5%} C-/P-type asteroids (with the majority of these being P-types).

  6. On the Onset of the Rainy Season in Amazonia: WHAT the Observations Show, and Why the Biases in Climate Models?

    NASA Astrophysics Data System (ADS)

    Marengo, J. A.; Alves, L. M.; Fu, R.

    2014-12-01

    The onset of the Amazon rainy season shows a large temporal and spatial variability, delays on the date of the onset will have strong impacts on local agriculture, hydroelectric power generation as well as on the hydrology of large rivers. Two "once-in-a-century" droughts occurred in 2005 and 2010, and it was shown that in those events the rainy season started later than normal, and also that on the last 10 years the dry season has increased in length by about one month. These events highlight the urgency for improving our understanding and capability to model onset of the rainy season and drought variability, for the present and future. Most studies have attributed the variability of the rainy season onset over Amazonia to the variability of the tropical oceans whether other factors, such as climate change, land use and aerosols also contribute to the variability are not clear.. Global climate models run on seasonal climate forecast mode still show large uncertainties on the prediction of onset of seasonal rains. As for climate change, the CMIP3 and CMIP5 appear to underestimate the past variability, and also project virtually no future change of the onset of rainy season over the Amazon even when they are forced by strong greenhouse forcing under the RCP8.5 emission scenario. Why these models underestimate the variability of the rainy season onset, and whether this bias implies an underestimate of sensitivity of their dry season length to anthropogenic radiative forcing remain unclear. This FAPESP DOE grant 2013/50538 aims to explore use of the measurements provided by the Atmospheric Radiation Measurement (ARM) Mobile Facilities (AMF)-GoAmazon and the Cloud processes of the main precipitation systems in Brazil (CHUVA) Field Experiments, along with global and regional model experiments, to explore the sources of the above described uncertainty. The project will address several issues, i.e. the inadequate representation of the types of convection (i.e., maritime versus continental) and their relationships to aerosols, land surface and atmospheric circulation as represented in climate models We will present our initial results addressing the factors that control the variability of the wet season onset over Amazonia, the influence of convective types on atmospheric diabatic heating based on GoAmazon and CHUVA.

  7. Mechanical thinning pillar peach trees - second year results and observations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Columnar (pillar) form peach trees were mechanically thinned at 50 days after full bloom during the pit hardening stage of development. A spike-drum mechanical shaker, which showed promise for peach fruit thinning, during preliminary tests in 2005 was used to remove the young fruits. The shaker wa...

  8. Palomar 5 and its tidal tails: New observational results

    SciTech Connect

    M. Odenkirchen et al.

    2003-02-06

    Sloan Digital Sky Survey data for the field of the cluster Pal 5 reveal the existence of a long massive stream of tidal debris spanning an arc of 10{sup o} on the sky. Pal 5 thus provides an outstanding example for tidal disruption of globular clusters in the Milky Way. Radial velocities from VLT spectra show that Pal 5 has an extremely low velocity dispersion, in accordance with the very low mass derived from its total luminosity.

  9. Plasma observations near Saturn - Initial results from Voyager 1

    NASA Technical Reports Server (NTRS)

    Bridge, H. S.; Belcher, J. W.; Lazarus, A. J.; Olbert, S.; Sullivan, J. D.; Bagenal, F.; Gazis, P. R.; Hartle, R. E.; Ogilvie, K. W.; Scudder, J. D.

    1981-01-01

    The Voyager 1 encounter with Saturn and its satellites yielded extensive measurements of magnetospheric low-energy plasma electrons and positive ions, both heavy and light, probably of hydrogen and nitrogen or oxygen. At radial distances between 15 and 7 Saturn radii on the inbound trajectory, the plasma appears to corotate with a velocity within 20% of that theoretically expected for rigid corotation. The Titan data, taken while the moon was inside the Saturn magnetosphere, shows a clear signature characteristic of the interaction between a subsonic corotating magnetospheric plasma and the atmospheric or ionospheric exosphere of Titan.

  10. New Results from Chandra Grating Observations of AGN

    NASA Astrophysics Data System (ADS)

    Yaqoob, T.; Padmanabhan, U.

    2002-12-01

    We present measurements of the Fe-K_alpha line for nine type I active galaxies using Chandra High Energy Transmission Grating Spectrometer (HETGS) data. The centroid energies are narrowly dispersed (6.403 +/- 0.062 keV) and indicate an origin of the main line peak in cold matter (FeXVII or lower). There may be contributions from higher ionization states to the total line profile but these are not discussed here. If all the line cores in this sample were the peaks of a relativistically broadened disk line the radial line emissivity law must be flat and the disk inclination angles must have a restricted range. At least three of the nine AGN clearly show a complex Fe-K_alpha line with an underlying broad component, possibly from a disk. In the others, an apparently narrow Fe-K_alpha line (even if it is resolved by Chandra) may still be due to the peak of a disk line. To distinguish this scenario from an origin in distant matter requires variability information.

  11. Genomic and Enzymatic Results Show Bacillus cellulosilyticus Uses a Novel Set of LPXTA Carbohydrases to Hydrolyze Polysaccharides

    PubMed Central

    Mead, David; Drinkwater, Colleen; Brumm, Phillip J.

    2013-01-01

    Background Alkaliphilic Bacillus species are intrinsically interesting due to the bioenergetic problems posed by growth at high pH and high salt. Three alkaline cellulases have been cloned, sequenced and expressed from Bacillus cellulosilyticus N-4 (Bcell) making it an excellent target for genomic sequencing and mining of biomass-degrading enzymes. Methodology/Principal Findings The genome of Bcell is a single chromosome of 4.7 Mb with no plasmids present and three large phage insertions. The most unusual feature of the genome is the presence of 23 LPXTA membrane anchor proteins; 17 of these are annotated as involved in polysaccharide degradation. These two values are significantly higher than seen in any other Bacillus species. This high number of membrane anchor proteins is seen only in pathogenic Gram-positive organisms such as Listeria monocytogenes or Staphylococcus aureus. Bcell also possesses four sortase D subfamily 4 enzymes that incorporate LPXTA-bearing proteins into the cell wall; three of these are closely related to each other and unique to Bcell. Cell fractionation and enzymatic assay of Bcell cultures show that the majority of polysaccharide degradation is associated with the cell wall LPXTA-enzymes, an unusual feature in Gram-positive aerobes. Genomic analysis and growth studies both strongly argue against Bcell being a truly cellulolytic organism, in spite of its name. Preliminary results suggest that fungal mycelia may be the natural substrate for this organism. Conclusions/Significance Bacillus cellulosilyticus N-4, in spite of its name, does not possess any of the genes necessary for crystalline cellulose degradation, demonstrating the risk of classifying microorganisms without the benefit of genomic analysis. Bcell is the first Gram-positive aerobic organism shown to use predominantly cell-bound, non-cellulosomal enzymes for polysaccharide degradation. The LPXTA-sortase system utilized by Bcell may have applications both in anchoring cellulases and other biomass-degrading enzymes to Bcell itself and in anchoring proteins other Gram-positive organisms. PMID:23593409

  12. Results of Lunar Impact Observations During Geminid Meteor Shower Events

    NASA Technical Reports Server (NTRS)

    Suggs, R. J.; Suggs, R. M.

    2015-01-01

    Meteoroids are natural particles with origins from comets, asteroids, and planets from within the solar system. On average, 33 metric tons (73,000 lb) of meteoroids hit Earth everyday with velocities ranging between 20 and 72 km/s. However, the vast majority of these meteoroids disintegrate in the atmosphere and never make it to the ground. The Moon also encounters the same meteoroid flux, but has no atmosphere to stop them from striking the surface. At such speeds even a small meteoroid has incredible energy. A meteoroid with a mass of only 5 kg can excavate a crater over 9 m across, hurling 75 metric tons (165,000 lb) of lunar soil and rock on ballistic trajectories above the lunar surface. Meteoroids with particle sizes as small as 100 micrometer (1 Microgram) can do considerable damage to spacecraft in Earth's orbit and beyond. Impacts can damage thermal protection systems, radiators, windows, and pressurized containers. Secondary effects might include partial penetration or pitting, local deformation, and surface degradation that can cause a failure upon reentry. The speed, mass, density, and flux of meteoroids are important factors for design considerations and mitigation during operations. Lunar operations (unmanned and manned) are also adversely affected by the meteoroid flux. Ejecta from meteoroid impacts is also part of the lunar environment and must be characterized. Understanding meteoroid fluxes and the associated risk of meteoroids impacting spacecraft traveling in and beyond Earth's orbit is the objective of the Meteoroid Environment Office (MEO) located at Marshall Space Flight Center (MSFC). One of the MEO's programs is meteoroid impact monitoring of the Moon. The large collecting area of the night side of the lunar disk provides statistically significant counts of meteoroids that can provide useful information about the flux of meteoroids in the hundreds of grams to kilograms size range. This information is not only important for characterizing the lunar environment associated with larger lunar impactors, but also provides statistical data for verification and improving meteoroid prediction models. Current meteoroid models indicate that the Moon is struck by a sporadic meteoroid with a mass greater than 1 kg over 260 times per year. This number is very uncertain since observations for objects in this mass range are few. Factors of several times, higher or lower, are easily possible. Meteor showers are also present to varying degrees at certain times of the year. The Earth experiences meteor showers when encountering the debris left behind by comets, which is also the case with 2 the Moon. During such times, the rate of shower meteoroids can greatly exceed that of the sporadic background rate for larger meteoroids. Looking for meteor shower impacts on the Moon at about the same time as they occur on Earth will yield important data that can be fed into meteor shower forecasting models, which can then be used to predict times of greater meteoroid hazard on the Moon. The Geminids are one such meteor shower of interest. The Geminids are a major meteor shower that occur in December with a peak intensity occurring usually during the 13th and 14th of the month and appearing to come from a radiant in the constellation Gemini. The Geminids are interesting in that the parent body of the debris stream is an asteroid, which along with the Quadrantids, are the only major meteor showers not originating from a comet. The Geminids parent body, 3200 Phaethon, is about 5 km in diameter and has an orbit that has a 22deg inclination which intersects the main asteroid belt and has a perihelion less than half of Mercury's perihelion distance. Thus, its orbit crosses those of Mars, Earth, Venus, and Mercury. The Geminid debris stream is by far the most massive as compared to the others. When the Earth passes through the stream in mid-December, a peak intensity of approx. equal 120 meteors per hour can be seen. Because of the Geminids' relatively large intensity and unique origin, it is important to monitor and gain information about the Geminids so as to improve their forecasts and understand their contribution to the meteoroid environment in Earth's orbit and at the Moon. It is the purpose of this Technical Memorandum (TM) to document two lunar observing periods coinciding with the Geminid meteor showers that occurred in 2006 and 2010.

  13. A processing method and results of meteor shower radar observations

    NASA Technical Reports Server (NTRS)

    Belkovich, O. I.; Suleimanov, N. I.; Tokhtasjev, V. S.

    1987-01-01

    Studies of meteor showers permit the solving of some principal problems of meteor astronomy: to obtain the structure of a stream in cross section and along its orbits; to retrace the evolution of particle orbits of the stream taking into account gravitational and nongravitational forces and to discover the orbital elements of its parent body; to find out the total mass of solid particles ejected from the parent body taking into account physical and chemical evolution of meteor bodies; and to use meteor streams as natural probes for investigation of the average characteristics of the meteor complex in the solar system. A simple and effective method of determining the flux density and mass exponent parameter was worked out. This method and its results are discussed.

  14. Ceres hyperspectral observations by VIR on Dawn: First Results

    NASA Astrophysics Data System (ADS)

    De Sanctis, M. C.; Ammannito, E.; Capaccioni, F.; Capria, M. T.

    2015-10-01

    The Dawn spacecraft [1] is at Ceres, the second of its targets. Ceres is the most massive body in the asteroid belt and was discovered in 1801 by Giuseppe Piazzi in the Palermo Observatory. It was catalogued by the IAU as a dwarf planet in 2006. Ceres (together with Vesta) represents the key to understand some important points relative to the role of the protoplanet size and the water content in determining the evolution of protoplanets and minor bodies. Ceres is thought to be differentiated, and hydrated minerals were proposed to exist on its surface [2,3]. Its low density [3] associated with the presence of transient water vapour[4], suggests a high content of ice inside the body and on its surface. Ceres seems to have been subject to differentiation and hydrothermal activity, and might host a liquid subsurface layer even today. Dawn is equipped with a Visible and InfraRed Mapping Spectrometer (VIR) [5] that fully accomplishes its scientific objectives at Ceres. Here we report about the first VIR results at Ceres.

  15. Distributed Permafrost Observation Network in Western Alaska: the First Results

    NASA Astrophysics Data System (ADS)

    Romanovsky, V. E.; Cable, W.; Marchenko, S. S.; Panda, S. K.

    2014-12-01

    The area of Western Alaska including the Selawik National Wildlife Refuge (SNWR) is generally underrepresented in terms of permafrost thermal monitoring. Thus, the main objective of this study was to establish a permafrost monitoring network in Western Alaska in order to understand the spatial variability in permafrost thermal regime in the area and to have a baseline in order to detect future change. Present and future thawing of permafrost in the region will have a dramatic effect on the ecosystems and infrastructure because the permafrost here generally has a high ice content, as a result of preservation of old ground ice in these relatively cold regions even during the warmer time intervals of the Holocene. Over the summers of 2011 and 2012 a total of 26 automated monitoring stations were established to collect temperature data from the active layer and near-surface permafrost. While most of these stations were basic and only measured the temperature down to 1.5 m at 4 depths, three of the stations had higher vertical temperature resolution down to 3 m. The sites were selected using an ecotype (basic vegetation groups) map of very high resolution (30 m) that had been created for the area in 2009. We found the Upland Dwarf Birch-Tussock Shrub ecotype to be the coldest with a mean annual ground temperature at 1 meter (MAGT1.0) of -3.9 °C during the August 1st, 2012 to July 31st, 2013 measurement period. This is also the most widespread ecotype in the SNWR, covering approximately 28.4% by area. The next widespread ecotype in the SNWR is the Lowland and Upland Birch-Ericaceous Low Shrub. This ecotype had higher ground temperatures with an average MAGT1.0 of -2.4 °C during the same measurement period. We also found that within some ecotypes (White Spruce and Alder-Willow Shrub) the presence or absence of moss on the surface seems to indicate the presence or absence of near surface permafrost. In general, we found good agreement between ecotype classes and permafrost characteristics such as temperature, active layer thickness, and freeze back duration. Thus, we believe it might be possible to translate the ecotype map into a very high spatial resolution (30 m) permafrost map using our measurements. Such a map would be useful in decision making with respect to land use and understanding how the landscape might change under future climate scenarios.

  16. Observations of net soil exchange of CO2 in a dryland show experimental warming increases carbon losses in biocrust soils

    USGS Publications Warehouse

    Darrouzet-Nardi, Anthony N.; Reed, Sasha C.; Grote, Ed; Belnap, Jayne

    2015-01-01

    Many arid and semiarid ecosystems have soils covered with well-developed biological soil crust communities (biocrusts) made up of mosses, lichens, cyanobacteria, and heterotrophs living at the soil surface. These communities are a fundamental component of dryland ecosystems, and are critical to dryland carbon (C) cycling. To examine the effects of warming temperatures on soil C balance in a dryland ecosystem, we used infrared heaters to warm biocrust-dominated soils to 2 °C above control conditions at a field site on the Colorado Plateau, USA. We monitored net soil exchange (NSE) of CO2 every hour for 21 months using automated flux chambers (5 control and 5 warmed chambers), which included the CO2 fluxes of the biocrusts and the soil beneath them. We observed measurable photosynthesis in biocrust soils on 12 % of measurement days, which correlated well with precipitation events and soil wet-up. These days included several snow events, providing what we believe to be the first evidence of substantial photosynthesis underneath snow by biocrust organisms in drylands. Overall, biocrust soils in both control and warmed plots were net CO2 sources to the atmosphere, with control plots losing 62 ± 8 g C m−2 (mean ± SE) over the first year of measurement and warmed plots losing 74 ± 9 g C m−2. Between control and warmed plots, the difference in soil C loss was uncertain over the course of the entire year due to large and variable rates in spring, but on days during which soils were wet and crusts were actively photosynthesizing, biocrusts that were warmed by 2 °C had a substantially more negative C balance (i.e., biocrust soils took up less C and/or lost more C in warmed plots). Taken together, our data suggest a substantial risk of increased C loss from biocrust soils with higher future temperatures, and highlight a robust capacity to predict CO2 exchange in biocrust soils using easily measured environmental parameters.

  17. Betaine and Trimethylamine-N-Oxide as Predictors of Cardiovascular Outcomes Show Different Patterns in Diabetes Mellitus: An Observational Study

    PubMed Central

    Lever, Michael; George, Peter M.; Slow, Sandy; Bellamy, David; Young, Joanna M.; Ho, Markus; McEntyre, Christopher J.; Elmslie, Jane L.; Atkinson, Wendy; Molyneux, Sarah L.; Troughton, Richard W.; Frampton, Christopher M.; Richards, A. Mark; Chambers, Stephen T.

    2014-01-01

    Background Betaine is a major osmolyte, also important in methyl group metabolism. Concentrations of betaine, its metabolite dimethylglycine and analog trimethylamine-N-oxide (TMAO) in blood are cardiovascular risk markers. Diabetes disturbs betaine: does diabetes alter associations between betaine-related measures and cardiovascular risk? Methods Plasma samples were collected from 475 subjects four months after discharge following an acute coronary admission. Death (n = 81), secondary acute MI (n = 87), admission for heart failure (n = 85), unstable angina (n = 72) and all cardiovascular events (n = 283) were recorded (median follow-up: 1804 days). Results High and low metabolite concentrations were defined as top or bottom quintile of the total cohort. In subjects with diabetes (n = 79), high plasma betaine was associated with increased frequencies of events; significantly for heart failure, hazard ratio 3.1 (1.2–8.2) and all cardiovascular events, HR 2.8 (1.4–5.5). In subjects without diabetes (n = 396), low plasma betaine was associated with events; significantly for secondary myocardial infarction, HR 2.1 (1.2–3.6), unstable angina, HR 2.3 (1.3–4.0), and all cardiovascular events, HR 1.4 (1.0–1.9). In diabetes, high TMAO was a marker of all outcomes, HR 2.7 (1.1–7.1) for death, 4.0 (1.6–9.8) for myocardial infarction, 4.6 (2.0–10.7) for heart failure, 9.1 (2.8–29.7) for unstable angina and 2.0 (1.1–3.6) for all cardiovascular events. In subjects without diabetes TMAO was only significant for death, HR 2.7 (1.6–4.8) and heart failure, HR 1.9 (1.1–3.4). Adding the estimated glomerular filtration rate to Cox regression models tended to increase the apparent risks associated with low betaine. Conclusions Elevated plasma betaine concentration is a marker of cardiovascular risk in diabetes; conversely low plasma betaine concentrations indicate increased risk in the absence of diabetes. We speculate that the difference reflects control of osmolyte retention in tissues. Elevated plasma TMAO is a strong risk marker in diabetes. PMID:25493436

  18. Evaluation of Observation-Fused Regional Air Quality Model Results for Population Air Pollution Exposure Estimation

    PubMed Central

    Chen, Gang; Li, Jingyi; Ying, Qi; Sherman, Seth; Perkins, Neil; Rajeshwari, Sundaram; Mendola, Pauline

    2014-01-01

    In this study, Community Multiscale Air Quality (CMAQ) model was applied to predict ambient gaseous and particulate concentrations during 2001 to 2010 in 15 hospital referral regions (HRRs) using a 36-km horizontal resolution domain. An inverse distance weighting based method was applied to produce exposure estimates based on observation-fused regional pollutant concentration fields using the differences between observations and predictions at grid cells where air quality monitors were located. Although the raw CMAQ model is capable of producing satisfying results for O3 and PM2.5 based on EPA guidelines, using the observation data fusing technique to correct CMAQ predictions leads to significant improvement of model performance for all gaseous and particulate pollutants. Regional average concentrations were calculated using five different methods: 1) inverse distance weighting of observation data alone, 2) raw CMAQ results, 3) observation-fused CMAQ results, 4) population-averaged raw CMAQ results and 5) population-averaged fused CMAQ results. It shows that while O3 (as well as NOx) monitoring networks in the HRR regions are dense enough to provide consistent regional average exposure estimation based on monitoring data alone, PM2.5 observation sites (as well as monitors for CO, SO2, PM10 and PM2.5 components) are usually sparse and the difference between the average concentrations estimated by the inverse distance interpolated observations, raw CMAQ and fused CMAQ results can be significantly different. Population-weighted average should be used to account spatial variation in pollutant concentration and population density. Using raw CMAQ results or observations alone might lead to significant biases in health outcome analyses. PMID:24747248

  19. Presentation Showing Results of a Hydrogeochemical Investigation of the Standard Mine Vicinity, Upper Elk Creek Basin, Colorado

    USGS Publications Warehouse

    Manning, Andrew H.; Verplanck, Philip L.; Mast, M. Alisa; Wanty, Richard B.

    2008-01-01

    PREFACE This Open-File Report consists of a presentation given in Crested Butte, Colorado on December 13, 2007 to the Standard Mine Advisory Group. The presentation was paired with another presentation given by the Colorado Division of Reclamation, Mining, and Safety on the physical features and geology of the Standard Mine. The presentation in this Open-File Report summarizes the results and conclusions of a hydrogeochemical investigation of the Standard Mine performed by the U.S. Geological Survey (Manning and others, in press). The purpose of the investigation was to aid the U.S. Environmental Protection Agency in evaluating remediation options for the Standard Mine site. Additional details and supporting data related to the information in this presentation can be found in Manning and others (in press).

  20. Selection Indices and Multivariate Analysis Show Similar Results in the Evaluation of Growth and Carcass Traits in Beef Cattle.

    PubMed

    Brito Lopes, Fernando; da Silva, Marcelo Corra; Magnabosco, Cludio Ulha; Goncalves Narciso, Marcelo; Sainz, Roberto Daniel

    2016-01-01

    This research evaluated a multivariate approach as an alternative tool for the purpose of selection regarding expected progeny differences (EPDs). Data were fitted using a multi-trait model and consisted of growth traits (birth weight and weights at 120, 210, 365 and 450 days of age) and carcass traits (longissimus muscle area (LMA), back-fat thickness (BF), and rump fat thickness (RF)), registered over 21 years in extensive breeding systems of Polled Nellore cattle in Brazil. Multivariate analyses were performed using standardized (zero mean and unit variance) EPDs. The k mean method revealed that the best fit of data occurred using three clusters (k = 3) (P < 0.001). Estimates of genetic correlation among growth and carcass traits and the estimates of heritability were moderate to high, suggesting that a correlated response approach is suitable for practical decision making. Estimates of correlation between selection indices and the multivariate index (LD1) were moderate to high, ranging from 0.48 to 0.97. This reveals that both types of indices give similar results and that the multivariate approach is reliable for the purpose of selection. The alternative tool seems very handy when economic weights are not available or in cases where more rapid identification of the best animals is desired. Interestingly, multivariate analysis allowed forecasting information based on the relationships among breeding values (EPDs). Also, it enabled fine discrimination, rapid data summarization after genetic evaluation, and permitted accounting for maternal ability and the genetic direct potential of the animals. In addition, we recommend the use of longissimus muscle area and subcutaneous fat thickness as selection criteria, to allow estimation of breeding values before the first mating season in order to accelerate the response to individual selection. PMID:26789008

  1. Selection Indices and Multivariate Analysis Show Similar Results in the Evaluation of Growth and Carcass Traits in Beef Cattle

    PubMed Central

    Brito Lopes, Fernando; da Silva, Marcelo Corrêa; Magnabosco, Cláudio Ulhôa; Goncalves Narciso, Marcelo; Sainz, Roberto Daniel

    2016-01-01

    This research evaluated a multivariate approach as an alternative tool for the purpose of selection regarding expected progeny differences (EPDs). Data were fitted using a multi-trait model and consisted of growth traits (birth weight and weights at 120, 210, 365 and 450 days of age) and carcass traits (longissimus muscle area (LMA), back-fat thickness (BF), and rump fat thickness (RF)), registered over 21 years in extensive breeding systems of Polled Nellore cattle in Brazil. Multivariate analyses were performed using standardized (zero mean and unit variance) EPDs. The k mean method revealed that the best fit of data occurred using three clusters (k = 3) (P < 0.001). Estimates of genetic correlation among growth and carcass traits and the estimates of heritability were moderate to high, suggesting that a correlated response approach is suitable for practical decision making. Estimates of correlation between selection indices and the multivariate index (LD1) were moderate to high, ranging from 0.48 to 0.97. This reveals that both types of indices give similar results and that the multivariate approach is reliable for the purpose of selection. The alternative tool seems very handy when economic weights are not available or in cases where more rapid identification of the best animals is desired. Interestingly, multivariate analysis allowed forecasting information based on the relationships among breeding values (EPDs). Also, it enabled fine discrimination, rapid data summarization after genetic evaluation, and permitted accounting for maternal ability and the genetic direct potential of the animals. In addition, we recommend the use of longissimus muscle area and subcutaneous fat thickness as selection criteria, to allow estimation of breeding values before the first mating season in order to accelerate the response to individual selection. PMID:26789008

  2. Marine Stratocumulus during VOCALS: Comparing Microphysical Observations to Large-Eddy Simulation Results

    NASA Astrophysics Data System (ADS)

    Petters, J.; Rossiter, D. L.; Feingold, G.; Jiang, H.; Chuang, P. Y.

    2010-12-01

    Large-eddy simulation (LES) is a tool capable of resolving cloud-scale processes and has been used extensively for study of the stratocumulus-topped boundary layer. Understanding the strengths and deficiencies of LES is crucial if we are to use it effectively. The ability of LES to accurately represent detailed microphysics has been sparsely investigated (Khairoutdinov and Kogan, 1999), and we seek to advance knowledge in this area. Here we study how well LES coupled with an explicit binned resolving model can simulate daytime observations of stratocumulus dynamics and microphysics during VOCALS. Our observations were acquired from the CIRPAS Twin Otter on October 19th, 2008 centered around 20 S, 72 W. During this day a well-mixed, non-drizzling stratus-topped boundary layer of ~300m thickness was observed. The cloud top height, thermodynamic profile, and wind profile all remained relatively stationary throughout the observation period. Potential temperature and moisture content jumps were 15.2 K and -6.55 g/kg, respectively. The Passive Cavity Aerosol Spectrometer Probe (PCASP) showed aerosol concentrations elevated (~600 cm^-3) from what is expected for clean maritime conditions. The Twin Otter was outfitted an airborne phase Doppler Interferometer (PDI) providing detailed microphysical information about the cloud layer. The PDI data show a monomodal drop size distribution that exhibits little change in shape with change in liquid water content (LWC), consistent with extreme inhomogeneous mixing of air parcels. For our numerical model we employ the Regional Atmospheric Modeling System (RAMS, Cotton et al., 2001) in LES mode. So that the results of our LES best matched the detailed microphysical data from the PDI, we coupled a binned microphysical model to our LES (Feingold et al., 1996; Tzivion et al., 1987). Our LES cloud top height after model spin-up then matches the observations while model cloud base is 25 m than observations. Comparisons between probability distribution functions of LWC at matched heights in the observations and the LES results show reasonable agreement. The strength of simulated boundary-layer circulations is substantially weaker than what the observations suggest. These weak circulations are associated with a somewhat decoupled cloud layer in the LES which was not evident in our daytime observations. We suggest that this decoupling could be related to modeled overentrainment of free tropospheric air. Our model cloud top increases by 10 m over one hour of simulation, while no cloud top height increase was observed. For large LWCs (0.3 g/kg or greater) LES predicts drop size distribution remarkably well. For lower LWCs, the LES shows a substantial tail to smaller drop sizes not present in the observations. We attribute this discrepancy to the assumption of purely homogeneous mixing in the LES model. The LES also predicts a substantial number of small cloud droplets (~ 2 micron diameter) that are not observed by the PDI.

  3. Comparison of LFM Simulation Results with Observation for Strongly Northward IMF

    NASA Astrophysics Data System (ADS)

    Bhattarai, S. K.; Lopez, R. E.; Bruntz, R. J.

    2011-12-01

    The dynamics involved in solar wind magnetosphere coupling when interplanetary magnetic field (IMF) is northward is still poorly understood. When IMF is northward the coupling occurs at high latitude poleward of the cusp region. One of the methods of measuring this coupling is to calculate the polar cap potential (PCP). PCP is the difference between the maximum and minimum potential in the polar cap region. In this paper we show results obtained from Lyon Feeder Mobbary (LFM) simulation as well as satellite observation showing saturation of polar cap potential for strongly northward IMF. Furthermore, we compare the overall magnetosphere geometry obtained from ideal LFM simulation result with various satellite data during similar conditions of strongly northward IMF.

  4. The Bulge Radial Velocity Assay: Three Years of Observations and Results

    NASA Astrophysics Data System (ADS)

    Howard, Christian D.; Reitzel, D. B.; Rich, R. M.; Zhao, H.

    2007-12-01

    We present continuing results of a large scale radial velocity survey of the Galactic bulge, using M giant stars selected from the 2MASS catalogue as targets for the CTIO 4m Hydra multi-object spectrograph. The purpose of this survey is to test dynamical models of the bulge and to detect the presence, if any, of cold stellar streams in the bulge and its vicinity. We report on over three years of observations of approximately 3500 stars which allow us to sample the kinematics the bulge major axis at -10observations of candidate stellar stream fields observed in 2006 are presented, along with disk field observations. Comparison of the data to current models shows disagreement with either predicted rotation, predicted dispersion, or both, and shall be discussed. RMR, DBR, and CDH acknowledge support from NSF grant AST-0709479 and grant GO-10868 from the Space Telescope Science Institute

  5. Upper Stratospheric Temperature Climatology Derived from SAGE II Observations: Preliminary Results

    NASA Technical Reports Server (NTRS)

    Wang, P.-H.; Cunnold, D. M.; Wang, H. J.; Chu, W. P.; Thomason, L. W.

    2002-01-01

    This study shows that the temperature information in the upper stratosphere can be derived from the SAGE II 385-mn observations. The preliminary results indicate that the zonal mean temperature increases with altitude below 50 km and decreases above 50 km. At 50 km, a regional maximum of 263 K is located in the tropics, and a minimum of 261 K occurs in the subtropics in both hemispheres. The derived long-term temperature changes from 1985 to 1997 reveal a statistically significant negative trend of -2 to -2.5 K/decade in the tropical upper stratosphere and about -2 K/decade in the subtropics near the stratopause. At latitudes poleward of 50, the results show a statistically significant positive trend of about 1 K/decade in the upper stratosphere. The preliminary results also show large annual temperature oscillations in the extratropics with a maximum amplitude of approx. 8 K located at about 44 km near 50 in both hemispheres during local summer. In addition, the semiannual oscillation is found to be a maximum in the tropics with a peak amplitude of approx. 3.3 K located at about 42 km during the equinox.

  6. A Portrait of the Centaur 2060 Chiron: new results from groundbased and Herschel observations

    NASA Astrophysics Data System (ADS)

    Fornasier, S.; Lellouch, E.; Mller, T.; Panuzzo, P.; Kiss, C.; Lim, T.; Mommert, M.; Bockele-Morvan, D.; Vilenius, E.; Tozzi, G. P.; Mottola, S.; Duffard, R.; Barucci, M. A.

    2013-09-01

    The Herschel Open Time Key Program entitled "TNOs are Cool: A survey of the trans-Neptunian region" has been awarded 373 hours to investigate the albedo, size distribution and thermal properties of TNOs and Centaurs [1]. In this work we present the results of the combined SPIRE and PACS instruments observations over 6 bands of the Centaur 2060 Chiron, together with groundbased observations used to constrain its absolute magnitude, to investigate possible cometary activity and its surface composition. The estimated nuclear HV magnitude during the Herschel observations is 5.810.08, indicating a high flux from the Centaur comparable to that of its activity peak during 1989. Using this HV value, our Chiron's best size estimation, from NEATM and TPM modelling, is 21820 km, with an albedo of 163 %, a value higher than previous Chiron's albedo estimation. Chiron shows the strongest decrease in the emissivity versus wavelength in the TNOs and Centaurs sample investigated with the PACS and SPIRE instruments. The results on the cometary activity analysis both in the visual and far infrared images will also be presented.

  7. A numerical modeling study of a Montana thunderstorm. I - Model results versus observations involving nonelectrical aspects. II - Model results versus observations involving electrical aspects

    NASA Technical Reports Server (NTRS)

    Helsdon, John H., Jr.; Farley, Richard D.

    1987-01-01

    Model results and the observed cloud behavior are examined in terms of nonelectrical and electrical aspects of a thunderstorm. The characteristics of the two-dimensional, time-dependent atmospheric electricity model used to simulate the cloud observations of July 19, 1981 in Miles City, Montana are described. The interactions of the dynamics and microphysics of the cloud with the charge separation mechanisms are analyzed. It is observed that the model accurately represents many of the observed characteristics of the cloud; however, the cloud base height, maximum liquid water content, and the time from first formation of precipitation until it reaches the ground are not accurately modeled. It is found that the model adequately represents the electrical field structure of the cloud and the electrical field strengths.

  8. CHEERS Results on Mrk 573: A Study of Deep Chandra Observations

    NASA Astrophysics Data System (ADS)

    Paggi, Alessandro; Wang, Junfeng; Fabbiano, Giuseppina; Elvis, Martin; Karovska, Margarita

    2012-09-01

    We present results on Mrk 573 obtained as part of the CHandra survey of Extended Emission-line Regions in nearby Seyfert galaxies (CHEERS). Previous studies showed that this source features a biconical emission in the soft X-ray band closely related to the narrow-line region as mapped by the [O III] emission line and the radio emission, though on a smaller scale; we investigate the properties of soft X-ray emission from this source with new deep Chandra observations. Making use of the subpixel resolution of the Chandra/ACIS image and point-spread function deconvolution, we resolve and study substructures in each ionizing cone. The two cone spectra are fitted with a photoionization model, showing a mildly photoionized phase diffused over the bicone. Thermal collisional gas at about ~1.1 keV and ~0.8 keV appears to be located between the nucleus and the "knots" resolved in radio observations, and between the "arcs" resolved in the optical images, respectively; this can be interpreted in terms of shock interaction with the host galactic plane. The nucleus shows a significant flux decrease across the observations indicating variability of the active galactic nucleus (AGN), with the nuclear region featuring a higher ionization parameter with respect to the bicone region. The long exposure allows us to find extended emission up to ~7 kpc from the nucleus along the bicone axis. Significant emission is also detected in the direction perpendicular to the ionizing cones, disagreeing with the fully obscuring torus prescribed in the AGN unified model and suggesting instead the presence of a clumpy structure.

  9. Spectral heterogeneity on Phobos and Deimos: HiRISE observations and comparisons to Mars Pathfinder results

    NASA Astrophysics Data System (ADS)

    Thomas, N.; Stelter, R.; Ivanov, A.; Bridges, N. T.; Herkenhoff, K. E.; McEwen, A. S.

    2011-10-01

    The High-Resolution Imaging Science Experiment (HiRISE) onboard Mars Reconnaissance Orbiter (MRO) has been used to observe Phobos and Deimos at spatial scales of around 6 and 20 m/px, respectively. HiRISE (McEwen et al., JGR, 112, CiteID E05S02, DOI: 10.1029/2005JE002605, 2007) has provided, for the first time, high-resolution colour images of the surfaces of the Martian moons. When processed, by the production of colour ratio images for example, the data show considerable small-scale heterogeneity, which might be attributable to fresh impacts exposing different materials otherwise largely hidden by a homogenous regolith. The bluer material that is draped over the south-eastern rim of the largest crater on Phobos, Stickney, has been perforated by an impact to reveal redder material and must therefore be relatively thin. A fresh impact with dark crater rays has been identified. Previously identified mass-wasting features in Stickney and Limtoc craters stand out strongly in colour. The interior deposits in Stickney appear more inhomogeneous than previously suspected. Several other local colour variations are also evident. Deimos is more uniform in colour but does show some small-scale inhomogeneity. The bright streamers (Thomas et al., Icarus, 123, 536-556,1996) are relatively blue. One crater to the south-west of Voltaire and its surroundings appear quite strongly reddened with respect to the rest of the surface. The reddening of the surroundings may be the result of ejecta from this impact. The spectral gradients at optical wavelengths observed for both Phobos and Deimos are quantitatively in good agreement with those found by unresolved photometric observations made by the Imager for Mars Pathfinder (IMP; Thomas et al., JGR, 104, 9055-9068, 1999). The spectral gradients of the blue and red units on Phobos bracket the results from IMP.

  10. Long Term Seismic Observation in Mariana by OBSs : Results of the DD inversion

    NASA Astrophysics Data System (ADS)

    Shiobara, H.; Sugioka, H.; Mochizuki, K.; Oki, S.; Kanazawa, T.; Fukao, Y.; Suyehiro, K.

    2004-12-01

    In order to obtain the deep arc structural image of Mariana, a large-scale seismic observation by using 58 long-term ocean bottom seismometers (LTOBS) had been performed from June 2003 until April 2004, which is a part of the MARGINS program funded by the NSF. Prior to this observation, a pilot long-term seismic array observation was conducted in the same area by using 10 LTOBSs from Oct. 2001 until Feb. 2003. By using seven LTOBS's data, those are about 11 months long, hypocenter determination was performed at first and more than 3000 local events were found, although the PDE list contains only 59. A 1D velocity structure based on the iasp91 model was used, and a systematic shift of epicenters between the PDE list and this study was seen. To investigate the detail of hypocenter distribution and the 3D velocity structure, the DD inversion (tomoDD: Zhang and Thurber, 2003) was applied for this data set with a 1D structure initial model except for the crust, which has been surveyed by using a dense airgun-OBS system (Takahashi et al., 2003). The result of relocated hypocenters shows double seismic zones until about 200km depth and a lined focuses along the current ridge axis in the back-arc basin, and the result of the tomographic inversion shows a image of subducting slab and a low-Vs region below the Pagan island erupted in 1981 at 80km depth. The mantle structure beneath the back-arc basin was not clearly resolved due to the inadequate source-receiver coverage, which is cleared in the recent experiment.

  11. Stable isotopes in precipitation recording South American summer monsoon and ENSO variability: observations and model results

    NASA Astrophysics Data System (ADS)

    Vuille, M.; Werner, M.

    2005-09-01

    The South American Summer Monsoon (SASM) is a prominent feature of summertime climate over South America and has been identified in a number of paleoclimatic records from across the continent, including records based on stable isotopes. The relationship between the stable isotopic composition of precipitation and interannual variations in monsoon strength, however, has received little attention so far. Here we investigate how variations in the intensity of the SASM influence ?18O in precipitation based on both observational data and Atmospheric General Circulation Model (AGCM) simulations. An index of vertical wind shear over the SASM entrance (low level) and exit (upper level) region over the western equatorial Atlantic is used to define interannual variations in summer monsoon strength. This index is closely correlated with variations in deep convection over tropical and subtropical South America during the mature stage of the SASM. Observational data from the International Atomic Energy Agency-Global Network of Isotopes in Precipitation (IAEA-GNIP) and from tropical ice cores show a significant negative association between ?18O and SASM strength over the Amazon basin, SE South America and the central Andes. The more depleted stable isotopic values during intense monsoon seasons are consistent with the so-called amount effect, often observed in tropical regions. In many locations, however, our results indicate that the moisture transport history and the degree of rainout upstream may be more important factors explaining interannual variations in ?18O. In many locations the stable isotopic composition is closely related to El Nio-Southern Oscillation (ENSO), even though the moisture source is located over the tropical Atlantic and precipitation is the result of the southward expansion and intensification of the SASM during austral summer. ENSO induces significant atmospheric circulation anomalies over tropical South America, which affect both SASM precipitation and ?18O variability. Therefore many regions show a weakened relationship between SASM and ?18O, once the SASM signal is decomposed into its ENSO-, and non-ENSO-related variance.

  12. NuSTAR results and future plans for magnetar and rotation-powered pulsar observations

    NASA Astrophysics Data System (ADS)

    An, H.; Kaspi, V. M.; Archibald, R.; Bachetti, M.; Bhalerao, V.; Bellm, E. C.; Beloborodov, A. M.; Boggs, S. E.; Chakrabarty, D.; Christensen, F. E.; Craig, W. W.; Dufour, F.; Forster, K.; Gotthelf, E. V.; Grefenstette, B. W.; Hailey, C. J.; Harrison, F. A.; Hascot, R.; Kitaguchi, T.; Kouveliotou, Ch.; Madsen, K. K.; Mori, K.; Pivovaroff, M. J.; Rana, V. R.; Stern, D.; Tendulkar, S.; Tomsick, J. A.; Vogel, J. K.; Zhang, W. W.; NuSTAR Team

    2014-03-01

    The Nuclear Spectroscopic Telescope Array (NuSTAR) is the first focusing hard X-ray mission in orbit and operates in the 3-79 keV range. NuSTAR's sensitivity is roughly two orders of magnitude better than previous missions in this energy band thanks to its superb angular resolution. Since its launch in 2012 June, NuSTAR has performed excellently and observed many interesting sources including four magnetars, two rotation-powered pulsars and the cataclysmic variable AE Aquarii. NuSTAR also discovered 3.76-s pulsations from the transient source SGR J1745-29 recently found by Swift very close to the Galactic center, clearly identifying the source as a transient magnetar. For magnetar 1E 1841-045, we show that the spectrum is well fit by an absorbed blackbody plus broken power-law model with a hard power-law photon index of 1.3. This is consistent with previous results by INTEGRAL and RXTE. We also find an interesting double-peaked pulse profile in the 25-35 keV band. For AE Aquarii, we show that the spectrum can be described by a multi-temperature thermal model or a thermal plus non-thermal model; a multi-temperature thermal model without a non-thermal component cannot be ruled out. Furthermore, we do not see a spiky pulse profile in the hard X-ray band, as previously reported based on Suzaku observations. For other magnetars and rotation-powered pulsars observed with NuSTAR, data analysis results will be soon available.

  13. Spectral heterogeneity on Phobos and Deimos: HiRISE observations and comparisons to Mars Pathfinder results

    USGS Publications Warehouse

    Thomas, N.; Stelter, R.; Ivanov, A.; Bridges, N.T.; Herkenhoff, K. E.; McEwen, A.S.

    2011-01-01

    The High-Resolution Imaging Science Experiment (HiRISE) onboard Mars Reconnaissance Orbiter (MRO) has been used to observe Phobos and Deimos at spatial scales of around 6 and 20 m/px, respectively. HiRISE (McEwen et al.; JGR, 112, CiteID E05S02, DOI: 10.1029/2005JE002605, 2007) has provided, for the first time, high-resolution colour images of the surfaces of the Martian moons. When processed, by the production of colour ratio images for example, the data show considerable small-scale heterogeneity, which might be attributable to fresh impacts exposing different materials otherwise largely hidden by a homogenous regolith. The bluer material that is draped over the south-eastern rim of the largest crater on Phobos, Stickney, has been perforated by an impact to reveal redder material and must therefore be relatively thin. A fresh impact with dark crater rays has been identified. Previously identified mass-wasting features in Stickney and Limtoc craters stand out strongly in colour. The interior deposits in Stickney appear more inhomogeneous than previously suspected. Several other local colour variations are also evident. Deimos is more uniform in colour but does show some small-scale inhomogeneity. The bright streamers (Thomas et al.; Icarus, 123, 536556,1996) are relatively blue. One crater to the south-west of Voltaire and its surroundings appear quite strongly reddened with respect to the rest of the surface. The reddening of the surroundings may be the result of ejecta from this impact. The spectral gradients at optical wavelengths observed for both Phobos and Deimos are quantitatively in good agreement with those found by unresolved photometric observations made by the Imager for Mars Pathfinder (IMP; Thomas et al.; JGR, 104, 90559068, 1999). The spectral gradients of the blue and red units on Phobos bracket the results from IMP. ?? 2010 Elsevier Ltd. All rights reserved.

  14. NuSTAR Results and Future Plans for Magnetar and Rotation-Powered Pulsar Observations

    NASA Technical Reports Server (NTRS)

    An, H.; Kaspi, V. M.; Archibald, R.; Bachetti, M.; Bhalerao, V.; Bellm, E. C.; Beloborodov, A. M.; Boggs, S. E.; Chakrabarty, D.; Christensen, F. E.; Craig, W. W.; Dufour, F.; Forster, K.; Gotthelf, B. W.; Grefenstette, B. W.; Hailey, C. J.; Harrison, F. A.; Hascoet, R.; Kitaguchi, T.; Kouveliotou, Ch.; Madsen, K. K.; Mori, K.; Pivovaroff, M. J.; Rana, V. R.; Stern, D.; Tendulkar, S.; Tomsick, J. A.; Vogel, J. K.; Zhang, William W.

    2014-01-01

    The Nuclear Spectroscopic Telescope Array (NuSTAR) is the first focusing hard X-ray mission in orbit and operates in the 3-79 keV range. NuSTAR's sensitivity is roughly two orders of magnitude better than previous missions in this energy band thanks to its superb angular resolution. Since its launch in 2012 June, NuSTAR has performed excellently and observed many interesting sources including four magnetars, two rotation-powered pulsars and the cataclysmic variable AE Aquarii. NuSTAR also discovered 3.76-s pulsations from the transient source SGR J1745-29 recently found by Swift very close to the Galactic center, clearly identifying the source as a transient magnetar. For magnetar 1E 1841-045, we show that the spectrum is well fit by an absorbed blackbody plus broken power-law model with a hard power-law photon index of approximately 1.3. This is consistent with previous results by INTEGRAL and RXTE. We also find an interesting double-peaked pulse profile in the 25-35 keV band. For AE Aquarii, we show that the spectrum can be described by a multi-temperature thermal model or a thermal plus non-thermal model; a multi-temperature thermal model without a non-thermal component cannot be ruled out. Furthermore, we do not see a spiky pulse profile in the hard X-ray band, as previously reported based on Suzaku observations. For other magnetars and rotation-powered pulsars observed with NuSTAR, data analysis results will be soon available.

  15. NuSTAR Results and Future Plans for Magnetar and Rotation-Powered Pulsar Observations

    NASA Technical Reports Server (NTRS)

    An, Hongjun; Kaspi, Victoria M.; Archibald, Robert; Bachetti, Matteo; Bhalerao, Varun; Bellm, Eric C.; Beloborodov, Andrei M.; Boggs, Steven E.; Chakrabarty, Deepto; Christensen, Finn E.; Craig, William W.; Dufour, Francis; Forster, Karl; Gotthelf, Eric V.; Grefenstette, Finn E.; Hailey, Charles J.; Harrison, Fiona A.; Hascoet, Romain; Kitaguchi, Takao; Madsen, Kristin K.; Kouvelioutou, Chryssa; Mori, Kaya; Pivovaroff, Michael J.; Rana, Vikram R.; Stern, Daniel; Tendulkar, Shriharsh; Tomsick, John A.; Vogel, Julia K.; Zhang, William W.

    2014-01-01

    The Nuclear Spectroscopic Telescope Array (NuSTAR) is the first focusing hard X-ray mission in orbit and operates in the 3-79 keV range. NuSTAR's sensitivity is roughly two orders of magnitude better than previous missions in this energy band thanks to its superb angular resolution. Since its launch in 2012 June, NuSTAR has performed excellently and observed many interesting sources including four magnetars, two rotation-powered pulsars and the cataclysmic variable AE Aquarii. NuSTAR also discovered 3.76-s pulsations from the transient source SGR J1745-29 recently found by Swift very close to the Galactic Center, clearly identifying the source as a transient magnetar. For magnetar 1E 1841-045, we show that the spectrum is well fit by an absorbed blackbody plus broken power-law model with a hard power-law photon index of approximately 1.3. This is consistent with previous results by INTEGRAL and RXTE. We also find an interesting double-peaked pulse profile in the 25-35 keV band. For AE Aquarii, we show that the spectrum can be described by a multi-temperature thermal model or a thermal plus non-thermal model; a multi-temperature thermal model without a non-thermal component cannot be ruled out. Furthermore, we do not see a spiky pulse profile in the hard X-ray band, as previously reported based on Suzaku observations. For other magnetars and rotation-powered pulsars observed with NuSTAR, data analysis results will be soon available.

  16. Multilayer Perceptron Model for Nowcasting Visibility from Surface Observations: Results and Sensitivity to Dissimilar Station Altitudes

    NASA Astrophysics Data System (ADS)

    Chaudhuri, Sutapa; Das, Debanjana; Sarkar, Ishita; Goswami, Sayantika

    2015-10-01

    The reduction in the visibility during fog significantly influences surface as well as air transport operations. The prediction of fog remains difficult despite improvements in numerical weather prediction models. The present study aims at identifying a suitable neural network model with proper architecture to provide precise nowcast of the horizontal visibility during fog over the airports of three significantly affected metropolises of India, namely: Kolkata (2232'N; 8820'E), Delhi (2838'N; 7712'E) and Bengaluru (1295'N; 7772'E). The investigation shows that the multilayer perceptron (MLP) model provides considerably less error in nowcasting the visibility during fog over the said metropolises than radial basis function network, generalized regression neural network or linear neural network. The MLP models of different architectures are trained with the data and records from 2000 to 2010. The model results are validated with observations from 2011 to 2014. Our results reveal that MLP models with different configurations (1) four input layers, three hidden layers with three hidden nodes in each layer and a single output; (2) four input layers with two hidden layers having one hidden node in the first hidden layer and two hidden nodes in the second hidden layer, and a single output layer; and (3) four input layers with two hidden layers having two hidden nodes in each hidden layer and a single output layer] provide minimum error in nowcasting the visibility during fog over the airports of Kolkata, Delhi and Bengaluru, respectively. The results show that the MLP model is well suited for nowcasting visibility during fog with 6 h lead time, however, the study reveals that the MLP model sensitive to dissimilar station altitudes in nowcasting visibility, as the minimum prediction error for the three metropolises having dissimilar mean sea level altitudes is observed through different configurations of the model.

  17. Observation results by the TAMA300 detector on gravitational wave bursts from stellar-core collapses

    SciTech Connect

    Ando, Masaki; Aso, Youichi; Iida, Yukiyoshi; Nishi, Yuhiko; Otsuka, Shigemi; Seki, Hidetsugu; Soida, Kenji; Taniguchi, Shinsuke; Tochikubo, Kuniharu; Tsubono, Kimio; Yoda, Tatsuo; Arai, Koji; Beyersdorf, Peter; Kawamura, Seiji; Sato, Shuichi; Takahashi, Ryutaro; Tatsumi, Daisuke; Tsunesada, Yoshiki; Zhu, Zong-Hong; Fujimoto, Masa-Katsu

    2005-04-15

    We present data-analysis schemes and results of observations with the TAMA300 gravitational wave detector, targeting burst signals from stellar-core collapse events. In analyses for burst gravitational waves, the detection and fake-reduction schemes are different from well-investigated ones for a chirp wave analysis, because precise waveform templates are not available. We used an excess -power filter for the extraction of gravitational wave candidates, and developed two methods for the reduction of fake events caused by nonstationary noises of the detector. These analysis schemes were applied to real data from the TAMA300 interferometric gravitational wave detector. As a result, fake events were reduced by a factor of about 1000 in the best cases. In addition, in order to interpret the event candidates from an astronomical viewpoint, we performed a Monte-Carlo simulation with an assumed Galactic event distribution model and with burst waveforms obtained from numerical simulations of stellar-core collapses. We set an upper limit of 5.0x10{sup 3} events/sec on the burst gravitational wave event rate in our Galaxy with a confidence level of 90%. This work shows prospects on the search for burst gravitational waves, by establishing an analysis scheme for the observation data from an interferometric gravitational wave detector.

  18. Observation results by the TAMA300 detector on gravitational wave bursts from stellar-core collapses

    NASA Astrophysics Data System (ADS)

    Ando, Masaki; Arai, Koji; Aso, Youichi; Beyersdorf, Peter; Hayama, Kazuhiro; Iida, Yukiyoshi; Kanda, Nobuyuki; Kawamura, Seiji; Kondo, Kazuhiro; Mio, Norikatsu; Miyoki, Shinji; Moriwaki, Shigenori; Nagano, Shigeo; Numata, Kenji; Sato, Shuichi; Somiya, Kentaro; Tagoshi, Hideyuki; Takahashi, Hirotaka; Takahashi, Ryutaro; Tatsumi, Daisuke; Tsunesada, Yoshiki; Zhu, Zong-Hong; Akutsu, Tomomi; Akutsu, Tomotada; Araya, Akito; Asada, Hideki; Barton, Mark A.; Fujiki, Youhei; Fujimoto, Masa-Katsu; Fujita, Ryuichi; Fukushima, Mitsuhiro; Futamase, Toshifumi; Hamuro, Yusaku; Haruyama, Tomiyoshi; Hayakawa, Hideaki; Heinzel, Gerhard; Horikoshi, Gen'ichi; Iguchi, Hideo; Ioka, Kunihito; Ishitsuka, Hideki; Kamikubota, Norihiko; Kaneyama, Takaharu; Karasawa, Yoshikazu; Kasahara, Kunihiko; Kasai, Taketoshi; Katsuki, Mayu; Kawabe, Keita; Kawamura, Mari; Kawashima, Nobuki; Kawazoe, Fumiko; Kojima, Yasufumi; Kokeyama, Keiko; Kozai, Yoshihide; Kudoh, Hideaki; Kuroda, Kazuaki; Kuwabara, Takashi; Matsuda, Namio; Miura, Kazuyuki; Miyakawa, Osamu; Miyama, Shoken; Mizusawa, Hiromi; Musha, Mitsuru; Nagayama, Yoshitaka; Nakagawa, Ken'ichi; Nakamura, Takashi; Nakano, Hiroyuki; Nakao, Ken-Ichi; Nishi, Yuhiko; Ogawa, Yujiro; Ohashi, Masatake; Ohishi, Naoko; Okutomi, Akira; Oohara, Ken-Ichi; Otsuka, Shigemi; Saito, Yoshio; Sakata, Shihori; Sasaki, Misao; Sato, Kouichi; Sato, Nobuaki; Sato, Youhei; Seki, Hidetsugu; Sekido, Aya; Seto, Naoki; Shibata, Masaru; Shinkai, Hisaaki; Shintomi, Takakazu; Soida, Kenji; Suzuki, Toshikazu; Takamori, Akiteru; Takemoto, Shuzo; Takeno, Kohei; Tanaka, Takahiro; Taniguchi, Keisuke; Taniguchi, Shinsuke; Tanji, Toru; Taylor, C. T.; Telada, Souichi; Tochikubo, Kuniharu; Tokunari, Masao; Tomaru, Takayuki; Tsubono, Kimio; Tsuda, Nobuhiro; Uchiyama, Takashi; Ueda, Akitoshi; Ueda, Ken-Ichi; Usui, Fumihiko; Waseda, Koichi; Watanabe, Yuko; Yakura, Hiromi; Yamamoto, Akira; Yamamoto, Kazuhiro; Yamazaki, Toshitaka; Yanagi, Yuriko; Yoda, Tatsuo; Yokoyama, Jun'ichi; Yoshida, Tatsuru

    2005-04-01

    We present data-analysis schemes and results of observations with the TAMA300 gravitational wave detector, targeting burst signals from stellar-core collapse events. In analyses for burst gravitational waves, the detection and fake-reduction schemes are different from well-investigated ones for a chirp wave analysis, because precise waveform templates are not available. We used an excess -power filter for the extraction of gravitational wave candidates, and developed two methods for the reduction of fake events caused by nonstationary noises of the detector. These analysis schemes were applied to real data from the TAMA300 interferometric gravitational wave detector. As a result, fake events were reduced by a factor of about 1000 in the best cases. In addition, in order to interpret the event candidates from an astronomical viewpoint, we performed a Monte-Carlo simulation with an assumed Galactic event distribution model and with burst waveforms obtained from numerical simulations of stellar-core collapses. We set an upper limit of 5.0103 events/sec( on the burst gravitational wave event rate in our Galaxy with a confidence level of 90%. This work shows prospects on the search for burst gravitational waves, by establishing an analysis scheme for the observation data from an interferometric gravitational wave detector.

  19. Choosing observers for evaluation of aesthetic results in breast cancer conservative treatment

    SciTech Connect

    Cardoso, Maria Joao . E-mail: mjcard@mail.med.up.pt; Santos, Ana Cristina; Cardoso, Jaime; Barros, Henrique; Cardoso de Oliveira, Manuel

    2005-03-01

    Purpose: The subjective evaluation of aesthetic results in conservative breast cancer treatment has largely been used without questioning the observer's skills. The aim of this study was to evaluate interobserver agreement of the aesthetic results of breast cancer conservative treatment in three groups of observers with different levels of experience. Methods and materials: Photographs were taken of 55 women who had undergone conservative unilateral breast cancer treatment and 5 control women with no breast disease. The images were then distributed to 13 observers who were divided into three groups according to their experience in breast cancer treatment: experienced, medium experienced, and inexperienced. They were first asked to distinguish the patients from the controls and for the patients to identify the operated side. Subsequently, they were asked to classify the aesthetic result as excellent, good, fair, or poor. The accuracy in identifying controls, patients, and side of treatment was calculated individually for all observers. The interobserver agreement for the aesthetic result was calculated using observed agreement and multiple {kappa} statistic ({kappa}) in each of the three groups. Results: Inexperienced observers performed significantly worse than experienced observers in identifying controls, patients, and the side of treatment. Agreement of the aesthetic result was significantly greater in the group of experienced observers ({kappa} = 0.59) than in the medium experienced ({kappa} = 0.35) and inexperienced ({kappa} = 0.33) observers. Conclusion: Previous experience in breast cancer conservative treatment should be considered a prerequisite for the evaluation of the aesthetic results.

  20. "The Show"

    ERIC Educational Resources Information Center

    Gehring, John

    2004-01-01

    For the past 16 years, the blue-collar city of Huntington, West Virginia, has rolled out the red carpet to welcome young wrestlers and their families as old friends. They have come to town chasing the same dream for a spot in what many of them call "The Show". For three days, under the lights of an arena packed with 5,000 fans, the state's best

  1. Lya intensity mapping: current observational results from SDSS/BOSS and its future potential.

    NASA Astrophysics Data System (ADS)

    Croft, Rupert A.; Miralda-Escudé, Jordi; Zheng, Zheng

    2016-01-01

    Over the past 10 years, widefield optical survey telescopes have taken several million fiber spectra of objects in the night sky. This enormous dataset can be used to carry out optical intensity mapping measurements right now, as well as informing and motivating future dedicated instruments. Using cross-correlation techniques have made measurements of the large-scale structure of the Universe in the hydrogen Lyman-alpha line from SDSS/BOSS fiber spectra. We compare our results to the structure expected in the LambdaCDM cosmological model, and make the first global estimate of the Lyman-alpha luminosity density of the Universe. We discuss how lessons learned during our analysis can be applied to future experiments, and which observational tracers will be useful for further applications of these techniques. We also show how intensity mapping could dramatically enhance our ability to make measurements of new effects in galaxy clustering, such as general and special relativistic distortions.

  2. New Results from Space and Field Observations on the Aerosol Direct and Indirect Radiative Forcing

    NASA Technical Reports Server (NTRS)

    Kaufman, Yoram J.; Remer, Lorraine; Tanre, Didier; Boucher, Olivier; Chin, Mian; Dubovik, Oleg; Holben, Brent

    2002-01-01

    New space observations from the MODIS instrument on board the Terra satellite and analysis of POLDER data flown on the ADEOS satellite, show in great details the spatial and seasonal variability of the global aerosol system. These spaceborne instruments distinguish fine aerosol from man-made regional pollution and biomass burning from mostly natural coarse dust and sea salt aerosol. E.g. fine regional pollution in and around the Indian sub-continent, Europe and North America; smoke from biomass burning in Southern Africa and Southern America; coarse dust from West Africa and mixed dust pollution and smoke from West and central Africa and East Asia. These regions were also studied extensively in focused field experiments and by the distributed AERONET network. The results generate the first climatologies of the aerosol system, are used to derive the aerosol radiative effects and to estimate the anthropogenic component. The measurements are also used to evaluate each other and constrain aerosol transport models.

  3. Ultraviolet-excited High Rotational Level Molecular Hydrogen in Interstellar Clouds: Models and Observational Results

    NASA Astrophysics Data System (ADS)

    Lee, Dae-Hee; Pak, Soojong; van Dishoeck, Ewine F.

    We have calculated 2448 interstellar cloud models to investigate the formation and destruction of high rotational level H2 according to the combinations of five physical conditions: the input UV intensity, the H2 column density, cloud temperature, total density, and the H2 formation rate efficiency. The models include the populations of all the accessible states of H2 with the rotational quantum number J < 16 as a function of depth through the model clouds, and assume that the abundance of H2 is in a steady state governed primarily by the rate of formation on the grain surfaces and the rates of destruction by spontaneous fluorescent dissociation following absorption in the Lyman andWerner band systems (Black & van Dishoeck 1987). The high rotational levels J = 4 and J = 5 are both populated by direct formation into these levels of newly created molecules, and by pumping from J = 0 and J = 1, respectively. The model results show that N(4)/N(0) and N(5)/N(1) are proportional to the incident UV intensity, as predicted by Jura (1975), and are linearly decreased with the logarithm of molecular fraction, log f. Also, recent observational results are discussed with reference to the calculated models. Twenty-four high resolution spectra of H2 in the LMC and SMC (Tumlinson et al. 2002), and three translucent clouds (Sonnentrucker et al. 2002; Sonnentrucker et al. 2003; Rachford et al. 2001), observed by FUSE, provide an appropriate data set to examine the models. We have surveyed 54 early-type stars in the Galactic disk and halo with the Berkeley Extreme and Far-Ultraviolet Spectrometer (BEFS), part of the ORFEUS telescope, to obtain interstellar H2 absorption spectra for this research. The observed high rotational H2 level line ratios are well followed in the models, so that we can estimate the densities of the clouds from the models.

  4. Calibration results for NOAA-11 AVHRR channels 1 and 2 from congruent path aircraft observations

    NASA Technical Reports Server (NTRS)

    Abel, Peter; Guenther, B.; Galimore, Reginald N.; Cooper, John W.

    1993-01-01

    A method for using congruent atmospheric path aircraft-satellite observations to calibrate a satellite radiometer is presented. A calibrated spectroradiometer aboard a NASA ER-2 aircraft at an altitude of 19 km above White Sands (New Mexico) was oriented to view White Sands at the overpass time of the NOAA-11 AVHRR instrument along the same view vector as the satellite instrument. The data from six flights between November 1988 and October 1990 were transformed into corresponding estimates of AVHRR channel radiance at the satellite (derived from the aircraft measurements), and average counts (from the AVHRR measurements), both averaged across the footprint of the spectroradiometer. Prelaunch measurements of the AVHRR spectral response profiles are assumed, and the radiance spectrum measured by the spectroradiometer was adjusted to satellite altitude using the LOWTRAN-7 computer code. Results show reduced gains in both channel 1 (0.65 micron) and channel 2 (0.85 micron), compared to prelaunch values, with little further reduction in gain after 200 days in orbit. Results for the gain ratio (channel 1/channel 2), which is important for the calculation of the normalized vegetation index, show constant in-orbit values 5 percent above the prelaunch value.

  5. Planck intermediate results. XXIX. All-sky dust modelling with Planck, IRAS, and WISE observations

    NASA Astrophysics Data System (ADS)

    Planck Collaboration; Ade, P. A. R.; Aghanim, N.; Alves, M. I. R.; Aniano, G.; Arnaud, M.; Ashdown, M.; Aumont, J.; Baccigalupi, C.; Banday, A. J.; Barreiro, R. B.; Bartolo, N.; Battaner, E.; Benabed, K.; Benoit-Lévy, A.; Bernard, J.-P.; Bersanelli, M.; Bielewicz, P.; Bonaldi, A.; Bonavera, L.; Bond, J. R.; Borrill, J.; Bouchet, F. R.; Boulanger, F.; Burigana, C.; Butler, R. C.; Calabrese, E.; Cardoso, J.-F.; Catalano, A.; Chamballu, A.; Chiang, H. C.; Christensen, P. R.; Clements, D. L.; Colombi, S.; Colombo, L. P. L.; Couchot, F.; Crill, B. P.; Curto, A.; Cuttaia, F.; Danese, L.; Davies, R. D.; Davis, R. J.; de Bernardis, P.; de Rosa, A.; de Zotti, G.; Delabrouille, J.; Dickinson, C.; Diego, J. M.; Dole, H.; Donzelli, S.; Doré, O.; Douspis, M.; Draine, B. T.; Ducout, A.; Dupac, X.; Efstathiou, G.; Elsner, F.; Enßlin, T. A.; Eriksen, H. K.; Falgarone, E.; Finelli, F.; Forni, O.; Frailis, M.; Fraisse, A. A.; Franceschi, E.; Frejsel, A.; Galeotta, S.; Galli, S.; Ganga, K.; Ghosh, T.; Giard, M.; Gjerløw, E.; González-Nuevo, J.; Górski, K. M.; Gregorio, A.; Gruppuso, A.; Guillet, V.; Hansen, F. K.; Hanson, D.; Harrison, D. L.; Henrot-Versillé, S.; Hernández-Monteagudo, C.; Herranz, D.; Hildebrandt, S. R.; Hivon, E.; Holmes, W. A.; Hovest, W.; Huffenberger, K. M.; Hurier, G.; Jaffe, A. H.; Jaffe, T. R.; Jones, W. C.; Keihänen, E.; Keskitalo, R.; Kisner, T. S.; Kneissl, R.; Knoche, J.; Kunz, M.; Kurki-Suonio, H.; Lagache, G.; Lamarre, J.-M.; Lasenby, A.; Lattanzi, M.; Lawrence, C. R.; Leonardi, R.; Levrier, F.; Liguori, M.; Lilje, P. B.; Linden-Vørnle, M.; López-Caniego, M.; Lubin, P. M.; Macías-Pérez, J. F.; Maffei, B.; Maino, D.; Mandolesi, N.; Maris, M.; Marshall, D. J.; Martin, P. G.; Martínez-González, E.; Masi, S.; Matarrese, S.; Mazzotta, P.; Melchiorri, A.; Mendes, L.; Mennella, A.; Migliaccio, M.; Miville-Deschênes, M.-A.; Moneti, A.; Montier, L.; Morgante, G.; Mortlock, D.; Munshi, D.; Murphy, J. A.; Naselsky, P.; Natoli, P.; Nørgaard-Nielsen, H. U.; Novikov, D.; Novikov, I.; Oxborrow, C. A.; Pagano, L.; Pajot, F.; Paladini, R.; Paoletti, D.; Pasian, F.; Perdereau, O.; Perotto, L.; Perrotta, F.; Pettorino, V.; Piacentini, F.; Piat, M.; Plaszczynski, S.; Pointecouteau, E.; Polenta, G.; Ponthieu, N.; Popa, L.; Pratt, G. W.; Prunet, S.; Puget, J.-L.; Rachen, J. P.; Reach, W. T.; Rebolo, R.; Reinecke, M.; Remazeilles, M.; Renault, C.; Ristorcelli, I.; Rocha, G.; Roudier, G.; Rubiño-Martín, J. A.; Rusholme, B.; Sandri, M.; Santos, D.; Scott, D.; Spencer, L. D.; Stolyarov, V.; Sudiwala, R.; Sunyaev, R.; Sutton, D.; Suur-Uski, A.-S.; Sygnet, J.-F.; Tauber, J. A.; Terenzi, L.; Toffolatti, L.; Tomasi, M.; Tristram, M.; Tucci, M.; Umana, G.; Valenziano, L.; Valiviita, J.; Van Tent, B.; Vielva, P.; Villa, F.; Wade, L. A.; Wandelt, B. D.; Wehus, I. K.; Ysard, N.; Yvon, D.; Zacchei, A.; Zonca, A.

    2016-02-01

    We present all-sky modelling of the high resolution Planck, IRAS, and WISE infrared (IR) observations using the physical dust model presented by Draine & Li in 2007 (DL, ApJ, 657, 810). We study the performance and results of this model, and discuss implications for future dust modelling. The present work extends the DL dust modelling carried out on nearby galaxies using Herschel and Spitzer data to Galactic dust emission. We employ the DL dust model to generate maps of the dust mass surface density ΣMd, the dust optical extinction AV, and the starlight intensity heating the bulk of the dust, parametrized by Umin. The DL model reproduces the observed spectral energy distribution (SED) satisfactorily over most of the sky, with small deviations in the inner Galactic disk and in low ecliptic latitude areas, presumably due to zodiacal light contamination. In the Andromeda galaxy (M31), the present dust mass estimates agree remarkably well (within 10%) with DL estimates based on independent Spitzer and Herschel data. We compare the DL optical extinction AV for the diffuse interstellar medium (ISM) with optical estimates for approximately 2 × 105 quasi-stellar objects (QSOs) observed inthe Sloan Digital Sky Survey (SDSS). The DL AV estimates are larger than those determined towards QSOs by a factor of about 2, which depends on Umin. The DL fitting parameter Umin, effectively determined by the wavelength where the SED peaks, appears to trace variations in the far-IR opacity of the dust grains per unit AV, and not only in the starlight intensity. These results show that some of the physical assumptions of the DL model will need to be revised. To circumvent the model deficiency, we propose an empirical renormalization of the DL AV estimate, dependent of Umin, which compensates for the systematic differences found with QSO observations. This renormalization, made to match the AV estimates towards QSOs, also brings into agreement the DL AV estimates with those derived for molecular clouds from the near-IR colours of stars in the 2 micron all sky survey (2MASS). The DL model and the QSOs data are also used to compress the spectral information in the Planck and IRAS observations for the diffuse ISM to a family of 20 SEDs normalized per AV, parameterized by Umin, which may be used to test and empirically calibrate dust models. The family of SEDs and the maps generated with the DL model are made public in the Planck Legacy Archive.

  6. The ILAN sprite campaigns in Israel: results from 7 years of observations

    NASA Astrophysics Data System (ADS)

    Yair, Yoav; Rubanenko, Lior; Katzenelson, Dor; Rosenthal, Neta; Mezuman, Keren; Price, Colin

    2014-05-01

    The ILAN (Imaging of Lightning And Nocturnal flashes, http://ilanteam.com/) campaigns have been conducted since 2004 from Israel, observing winter thunderstorms in the eastern Mediterranean. We searched for transient luminous events using the standard commercial CCD cameras (Watec N100, 902H2 Ultimate) and the UFO-capture software for event detection, commonly used by other TLE- research groups in Europe and Japan. Winter thunderstorms mostly occur in conjunction with the passage of cold fronts in Cyprus lows, and thus TLEs are best observed when the storms are 200-300 km west of the Israeli coastline, above the Mediterranean Sea. We present statistical analysis of 505 sprites observed in 7 winter campaigns from 2006/7-2012/13. Results show a clear peak in the frequency of sprite detections, with maximum values (above 40% of events) between 00:30-02:50 LST (Local Standard Time, UT+2). This distribution is very different from that of lightning in the region, which peaks ~ 05:00 LST over the sea (Altaratz et al., 2001), hinting at the different temporal behavior of +CG flashes, known to be the major producers of sprites. The morphological distribution of 339 sprites is dominated by column sprites (49.3%) with angels (33.0%) and carrots (25.7%) being less frequent. This is similar to reports of winter sprites over the Sea of Japan (Matsudo et al., 2007). Other shapes (trees, wishbones, etc.; Bór, 2013) appear quite rarely. Single element events constitute 16.8% of observations, with 83.2% containing 2 elements or more. Clusters of homogenous types are slightly more frequent than mixed ones (55%). In some rare cases we observed 12-23 elements in a single sprite. The number of elements and the temporal distribution of different sprite types will be presented and compared with the properties of the parent thunderstorms. Altaratz, O., Levin Z. and Y. Yair, 2001: Winter thunderstorms in Israel - a study with lightning location systems and weather radar. Month. Weath. Rev., 129, 5, 1259-1266. Bór, J., 2013: Optically perceptible characteristics of sprites observed in Central Europe in 2007-2009. Jour. Atmos. Sol. Terr. Phys., 92, 151-177 doi.org/10.1016/j.jastp.2012.10.008. Matsudo Y., Suzuki T., Hayakawa M., Yamashita K., Ando Y., Michimoto K., Korepano V., 2007: Characteristics of Japanese winter sprites and their parent lightning as estimated by VHF lightning and ELF transients Jour. Atmos. Solar Terr. Phys., 69, 12, 1431-1446.

  7. Battery Performance of ADEOS (Advanced Earth Observing Satellite) and Ground Simulation Test Results

    NASA Technical Reports Server (NTRS)

    Koga, K.; Suzuki, Y.; Kuwajima, S.; Kusawake, H.

    1997-01-01

    The Advanced Earth Observing Satellite (ADEOS) is developed with the aim of establishment of platform technology for future spacecraft and inter-orbit communication technology for the transmission of earth observation data. ADEOS uses 5 batteries, consists of two packs. This paper describes, using graphs and tables, the ground simulation tests and results that are carried to determine the performance of the ADEOS batteries.

  8. Lunar impact flashes: Results from 56 hours of video survey data observed by using one telescope

    NASA Astrophysics Data System (ADS)

    Ait Moulay Larbi, M.; Benkhaldoun, Z.; Baratoux, D.; Daassou, A.; Bouley, S.

    2015-10-01

    Primarily observations are performed during 2013 and 2014 at AGM observatory of Marrakech by using one SC telescope in the aim of observing sporadic meteoroids impacting the lunar dark side. Here,we report results from 56 hours of video survey.

  9. Modeling upward brine migration through faults as a result of CO2 storage in the Northeast German Basin shows negligible salinization in shallow aquifers

    NASA Astrophysics Data System (ADS)

    Kuehn, M.; Tillner, E.; Kempka, T.; Nakaten, B.

    2012-12-01

    The geological storage of CO2 in deep saline formations may cause salinization of shallower freshwater resources by upward flow of displaced brine from the storage formation into potable groundwater. In this regard, permeable faults or fractures can serve as potential leakage pathways for upward brine migration. The present study uses a regional-scale 3D model based on real structural data of a prospective CO2 storage site in Northeastern Germany to determine the impact of compartmentalization and fault permeability on upward brine migration as a result of pressure elevation by CO2 injection. To evaluate the degree of salinization in the shallower aquifers, different fault leakage scenarios were carried out using a newly developed workflow in which the model grid from the software package Petrel applied for pre-processing is transferred to the reservoir simulator TOUGH2-MP/ECO2N. A discrete fault description is achieved by using virtual elements. A static 3D geological model of the CO2 storage site with an a real size of 40 km x 40 km and a thickness of 766 m was implemented. Subsequently, large-scale numerical multi-phase multi-component (CO2, NaCl, H2O) flow simulations were carried out on a high performance computing system. The prospective storage site, located in the Northeast German Basin is part of an anticline structure characterized by a saline multi-layer aquifer system. The NE and SW boundaries of the study area are confined by the Fuerstenwalde Gubener and the Lausitzer Abbruch fault zones represented by four discrete faults in the model. Two formations of the Middle Bunter were chosen to assess brine migration through faults triggered by an annual injection rate of 1.7 Mt CO2 into the lowermost formation over a time span of 20 years. In addition to varying fault permeabilities, different boundary conditions were applied to evaluate the effects of reservoir compartmentalization. Simulation results show that the highest pressurization within the storage formation with a relative pressure increase of up to 150 % after 20 years of injection is caused by strong compartmentalization effects if closed boundaries and closed faults are assumed. The CO2 plume is considerably smaller compared to those that develop when laterally open boundaries are applied. Laterally open boundaries and highly permeable faults lead to the strongest pressure dissipation and cause the CO2 plume to come up almost 3 km closer to the fault. Closed model boundaries in the lower aquifers and four highly permeable faults (> 1,000 mD) lead to the highest salinities in the uppermost Stuttgart formation with an average salinity increase of 0.24 % (407 mg/l) after 20 years of injection. Less salinity changes in the uppermost aquifers are observed with closed boundaries in the lower aquifers and only one major fault open for brine flow. Here, also fault permeability, unexpectedly does not significantly influence salinization in the uppermost Stuttgart formation. Salinity increases by 0.04% (75 mg/l) for a fault permeability of 1,000 mD and by at least 0.06 % (96 mg/l) for a fault permeability of 10,000 mD and until the end of injection. Taking into account the modeling results shallow aquifer salinization is not expected to be of concern for the investigated study area in the Northeastern German Basin.

  10. Observational results of a multi-telescope campaign in search of interstellar urea [(NH{sub 2}){sub 2}CO

    SciTech Connect

    Remijan, Anthony J.; Snyder, Lewis E.; Kuo, Hsin-Lun; Looney, Leslie W.; Friedel, Douglas N.; McGuire, Brett A.; Golubiatnikov, G. Yu; Lovas, Frank J.; Ilyushin, V. V.; Alekseev, E. A.; Dyubko, S. F.; McCall, Benjamin J.; Hollis, Jan M.

    2014-03-10

    In this paper, we present the results of an observational search for gas phase urea [(NH{sub 2}){sub 2}CO] observed toward the Sgr B2(N-LMH) region. We show data covering urea transitions from ∼100 GHz to 250 GHz from five different observational facilities: the Berkeley-Illinois-Maryland-Association (BIMA) Array, the Combined Array for Research in Millimeter-wave Astronomy (CARMA), the NRAO 12 m telescope, the IRAM 30 m telescope, and the Swedish-ESO Submillimeter Telescope (SEST). The results show that the features ascribed to urea can be reproduced across the entire observed bandwidth and all facilities by best-fit column density, temperature, and source size parameters which vary by less than a factor of two between observations merely by adjusting for telescope-specific parameters. Interferometric observations show that the emission arising from these transitions is cospatial and compact, consistent with the derived source sizes and emission from a single species. Despite this evidence, the spectral complexity of both (NH{sub 2}){sub 2}CO and of Sgr B2(N) makes the definitive identification of this molecule challenging. We present observational spectra, laboratory data, and models, and discuss our results in the context of a possible molecular detection of urea.

  11. The WEBT campaign to observe AO 0235+16 in the 2003-2004 observing season. Results from radio-to-optical monitoring and XMM-Newton observations

    NASA Astrophysics Data System (ADS)

    Raiteri, C. M.; Villata, M.; Ibrahimov, M. A.; Larionov, V. M.; Kadler, M.; Aller, H. D.; Aller, M. F.; Kovalev, Y. Y.; Lanteri, L.; Nilsson, K.; Papadakis, I. E.; Pursimo, T.; Romero, G. E.; Tersranta, H.; Tornikoski, M.; Arkharov, A. A.; Barnaby, D.; Berdyugin, A.; Bttcher, M.; Byckling, K.; Carini, M. T.; Carosati, D.; Cellone, S. A.; Ciprini, S.; Combi, J. A.; Crapanzano, S.; Crowe, R.; di Paola, A.; Dolci, M.; Fuhrmann, L.; Gu, M.; Hagen-Thorn, V. A.; Hakala, P.; Impellizzeri, V.; Jorstad, S.; Kerp, J.; Kimeridze, G. N.; Kovalev, Yu. A.; Kraus, A.; Krichbaum, T. P.; Kurtanidze, O. M.; Lhteenmki, A.; Lindfors, E.; Mingaliev, M. G.; Nesci, R.; Nikolashvili, M. G.; Ohlert, J.; Orio, M.; Ostorero, L.; Pasanen, M.; Pati, A.; Poteet, C.; Ros, E.; Ros, J. A.; Shastri, P.; Sigua, L. A.; Sillanp, A.; Smith, N.; Takalo, L. O.; Tosti, G.; Vasileva, A.; Wagner, S. J.; Walters, R.; Webb, J. R.; Wills, W.; Witzel, A.; Xilouris, E.

    2005-07-01

    A multiwavelength campaign to observe the BL Lac object AO 0235+16 (z=0.94) was set up by the Whole Earth Blazar Telescope (WEBT) collaboration during the observing seasons 2003-2004 and 2004-2005, involving radio, near-IR and optical photometric monitoring, VLBA monitoring, optical spectral monitoring, and three pointings by the XMM-Newton satellite. Here we report on the results of the first season, which involved the participation of 24 optical and near-IR telescopes and 4 radio telescopes, as well as the first XMM-Newton pointing, which occurred on January 18-19, 2004. Unpublished data from previous epochs were also collected (from 5 optical-NIR and 3 radio telescopes), in order to fill the gap between the end of the period presented in Raiteri et al. (2001) and the start of the WEBT campaign. The contribution of the southern AGN, 2 arcsec distant from the source, is taken into account. It is found to especially affect the blue part of the optical spectrum when the source is faint. In the optical and near-IR the source has been very active in the last 3 years, although it has been rather faint most of the time, with noticeable variations of more than a magnitude over a few days. In contrast, in the radio bands it appears to have been quiescent since early 2000. The major radio (and optical) outburst predicted to peak around February-March 2004 (with a six month uncertainty) has not occurred yet. When comparing our results with the historical light curves, two different behaviours seem to characterize the optical outbursts: only the major events present a radio counterpart. The X-ray spectra obtained by the three EPIC detectors are well fitted by a power law with extra-absorption at z=0.524; the energy index in the 0.2-10 keV range is well constrained: ?=0.645 0.028 and the 1 keV flux density is 0.311 0.008~? Jy. The analysis of the X-ray light curves reveals that no significant variations occurred during the pointing. In contrast, simultaneous dense radio monitoring with the 100 m telescope at Effelsberg shows a ~2-3% flux decrease in 6-7 h, which, if intrinsic, would imply a brightness temperature well above the Compton limit and hence a lower limit to the Doppler factor ? ? 46. We construct the broad-band spectral energy distribution of January 18-19, 2004 with simultaneous radio data from Effelsberg, optical data from the Nordic Optical Telescope (NOT), optical-UV data from the Optical Monitor onboard XMM-Newton, and X-ray data by the EPIC instruments. Particular care is taken to correct data for extinction due to both the Milky Way and the z=0.524 absorber. The resulting SED suggests the existence of a bump in the UV spectral region.

  12. Polarimetric Radar Observations of Arctic Clouds: Signal Processing and First Results from the may 2013 Iop

    NASA Astrophysics Data System (ADS)

    Galletti, M.; Oue, M.; Verlinde, J.

    2013-12-01

    The ARM Climate Research Facility site at the North Slope of Alaska in Barrow provides polarimetric radar observations of Arctic clouds at X, Ka and W bands. During the May 2013 Scanning radar Intensive Observation Period, raw I and Q data were acquired with the X-SAPR and the Ka-W SACR for the purpose of validating existing, and testing new signal processing procedures specifically tailored for Arctic observations. The raw I and Q datasets were collected on May 3rd 2013 for the case of low-level boundary layer mixed-phase arctic clouds and on May 6th 2013 for the case of a synoptic low moving in from the west. http://www.arm.gov/campaigns/nsa2013nsasr The present paper describes the impact of signal processing procedures on the data, and establishes dual-polarization radar as a valuable tool for the microphysical characterization of ice clouds. In particular, the X-SAPR operates at STSR mode, making available differential reflectivity ZDR, copolar correlation coefficient ρhv, specific differential phase KDP and Degree of Polarization at Simultaneous Transmit DOPS. Low-level boundary layer mixed-phase Arctic clouds are characterized by layers of supercooled liquid water aloft, which present a stark polarimetric contrast with respect to the associated ice precipitation fallout. The ice particles falling from boundary layer Arctic clouds on May 2nd, 3rd and 4th 2013 (winds were very weak or absent) showed the remarkable property of being composed exclusively by large dendrites - fern-like, stellars, twelve-branched - indicating deposition as the main accretion mechanism. http://www.flickr.com/photos/michele_galletti/sets/72157633422079814/ Boundary Layer mixed-phase Arctic clouds provide an exceptional natural laboratory for the exploration of polarimetric signatures in presence of dendritic ice particles. The first-ever X-band analysis of differential reflectivity ZDR of mixed-phase Arctic clouds is presented in [1]. For the May 6th case, ice particle populations associated with frontal systems underwent more significant vertical mixing, and therefore more significant break-up and aggregation, with the overall result that ice particles possessed less geometrical symmetry, and consequently less prominent polarimetric contrast was detected by the radars. [1] Oue, Galletti, Verlinde "Observations of X-band differential reflectivity in Arctic mixed-phase clouds", submitted.

  13. Vitamin D during pregnancy: why observational studies suggest deficiency and interventional studies show no improvement in clinical outcomes? A narrative review.

    PubMed

    Karras, S N; Anagnostis, P; Naughton, D; Annweiler, C; Petroczi, A; Goulis, D G

    2015-12-01

    A considerable number of studies have examined vitamin D status during pregnancy. Although data from observational studies denote vitamin D hypovitaminosis (deficiency or insufficiency) during pregnancy is associated with a plethora of adverse maternal and neonatal outcomes, data from interventional (supplementation) trials fail to reveal a significant impact on maternal and offspring health. The aim of this narrative review was to critically appraise the methodology of the most representative published randomized controlled trials in an attempt to explain the difference between observational and supplementation results. We found that this difference could be attributed to a variety of factors, namely: (i) study design (lack of a specific outcome in conjunction with timing of supplementation, enrolment of participants with heterogeneous vitamin D status); (ii) pitfalls in the interpretation of vitamin D equilibrium (lack of determination of plasma half-life); (iii) supplementation regimen (administration of a wide range of regimens, in terms of dose, bolus and form); (iv) geographical characteristics (vitamin D needs could vary significantly within a country, particularly in areas with a wide range of latitude gradient); (v) adaptations of vitamin D metabolism during pregnancy (vitamin D and calcium equilibrium are changed during pregnancy compared with the non-pregnant state) and (vi) supplementation of populations with low baseline 25(OH)D values would likely manifest beneficial effects. All these parameters should be taken into consideration in the design of future vitamin D supplementation trials. PMID:26219612

  14. Genetic susceptibility to childhood acute lymphoblastic leukemia shows protection in Malay boys: results from the Malaysia-Singapore ALL Study Group.

    PubMed

    Yeoh, Allen Eng-Juh; Lu, Yi; Chan, Jason Yong-Sheng; Chan, Yiong Huak; Ariffin, Hany; Kham, Shirley Kow-Yin; Quah, Thuan Chong

    2010-03-01

    To study genetic epidemiology of childhood acute lymphoblastic leukemia (ALL) in the Chinese and Malays, we investigated 10 polymorphisms encoding carcinogen- or folate-metabolism and transport. Sex-adjusted analysis showed NQO1 609CT significantly protects against ALL, whilst MTHFR 677CT confers marginal protection. Interestingly, we observed that NQO1 609CT and MTHFR 1298 C-allele have greater genetic impact in boys than in girls. The combination of SLC19A1 80GA heterozygosity and 3'-TYMS -6bp/-6bp homozygous deletion is associated with reduced ALL risk in Malay boys. Our study has suggested the importance of gender and race in modulating ALL susceptibility via the folate metabolic pathway. PMID:19651439

  15. The Relevance of External Quality Assessment for Molecular Testing for ALK Positive Non-Small Cell Lung Cancer: Results from Two Pilot Rounds Show Room for Optimization

    PubMed Central

    Tembuyser, Lien; Tack, Vronique; Zwaenepoel, Karen; Pauwels, Patrick; Miller, Keith; Bubendorf, Lukas; Kerr, Keith; Schuuring, Ed; Thunnissen, Erik; Dequeker, Elisabeth M. C.

    2014-01-01

    Background and Purpose Molecular profiling should be performed on all advanced non-small cell lung cancer with non-squamous histology to allow treatment selection. Currently, this should include EGFR mutation testing and testing for ALK rearrangements. ROS1 is another emerging target. ALK rearrangement status is a critical biomarker to predict response to tyrosine kinase inhibitors such as crizotinib. To promote high quality testing in non-small cell lung cancer, the European Society of Pathology has introduced an external quality assessment scheme. This article summarizes the results of the first two pilot rounds organized in 20122013. Materials and Methods Tissue microarray slides consisting of cell-lines and resection specimens were distributed with the request for routine ALK testing using IHC or FISH. Participation in ALK FISH testing included the interpretation of four digital FISH images. Results Data from 173 different laboratories was obtained. Results demonstrate decreased error rates in the second round for both ALK FISH and ALK IHC, although the error rates were still high and the need for external quality assessment in laboratories performing ALK testing is evident. Error rates obtained by FISH were lower than by IHC. The lowest error rates were observed for the interpretation of digital FISH images. Conclusion There was a large variety in FISH enumeration practices. Based on the results from this study, recommendations for the methodology, analysis, interpretation and result reporting were issued. External quality assessment is a crucial element to improve the quality of molecular testing. PMID:25386659

  16. Comparison of space-based lidar observations (CALIOP) with regional model results over Europe

    NASA Astrophysics Data System (ADS)

    Tegen, I.; Meier, J.; Wandinger, U.; Mattis, I.; Wolke, R.

    2012-12-01

    A regional transport model (COSMO-MUSCAT: Consortium for Small-scale Modeling - MultiScale Atmospheric Transport Model) is used for simulations of aerosol optical properties within Europe. Based on the simulated concentrations of specific aerosol types together with mass extinction efficiencies, vertical profiles of the extinction coefficients (EXTs) are calculated from the model results. Vertical profiles of backscatter coefficients (BSCs) are computed using a lidar ratio. In the model version used here marine and dust aerosol types are not computed. Model simulations are performed for two short time periods: 19-26 July 2006 and 16-26 February 2007. The summer period is characterized by low wind speeds and a persistent meteorological situation. This caused the accumulation of particles within the atmosphere. For this time period an average aerosol optical depth (AOD) of 0.19 is simulated, whereas due to particle removal by several precipitation events during the winter period the average AOD is lower (0.14). In this investigation space-based observations of vertical profiles of BSCs are used for model evaluation. CALIOP (Cloud-Aerosol Lidar with Orthogonal Polarization) performs global aerosol profile measurements since April 2006 continuously. In addition to the BSC profiles information about the occurrence of particular aerosol types (smoke, polluted dust, clean continental, polluted continental, dust and clean marine) is available. Comparisons between observed and simulated BSC profiles for these two time periods show a relative model bias of -23%- -10% during summer and of -77%- -53% during winter between surface and 2 km altitude. Especially, during the winter period the bias is quite large caused in part by the tendency of the model to remove particles too efficiently due to wet deposition. Further, during 19-26 July 2006 Saharan dust was transported to Europe, which is not described by the model, and marine aerosol is only identified by CALIOP over sea surface. Eliminating BSC profiles where marine and dust aerosol types were detected by CALIOP improves the agreement between observed and simulated BSC profiles. A relative bias of -20% - -2% during summer and of -72% - -46% during winter is determined. The relatively large discrepancy during winter time can also be caused by the misinterpretation of the occurrence of marine aerosol. Marine aerosol was dominant during that time but CALIOP detects marine aerosol only over sea surface, whereas the transport of marine aerosol into continental regions is not considered. Additionally, differences regarding day- and night-time are found. In general comparisons between CALIOP and COSMO-MUSCAT lead to better results for night-time compared to day-time observations. This difference has also been found in comparisons of CALIOP BSC profiles with ground-based lidar profiles. The results point to the need to implement dust and marine aerosol type for characterizing aerosol distribution within the regional model for the European domain. Additionally, by using CALIOP data it is possible to analyze model ability to simulate the occurrence, the transport as well as the optical properties of specific aerosol types.

  17. Results from GMRT 150 MHz Radio Observations: Search for Steep Spectrum Radio Sources

    NASA Astrophysics Data System (ADS)

    Ishwara-Chandra, C. H.; Marathe, R.

    2007-12-01

    We present results from deep 150 MHz low frequency radio observations with Giant Meterwave Radio Telescope (GMRT), India. GMRT consists of 30 antennas, each of 45 meter diameter operating at frequencies from 150 MHz to 1400 MHz. At 150 MHz, GMRT can image the sky with high resolution ( 20 arcsec) of area of 10 square degrees with single pointing, which allows to detect a few hundred radio sources down to 10 mJy. We have carried out deep imaging at 150 MHz of two fields; one surrounding Upsilon Andromeda and another encompassing the cluster Abell 764. The rms noise achieved is 2 mJy/beam. The resolution in both images were 20 arcsec. The radio spectral index analysis of the sources in the field using the higher frequency NVSS (1400 MHz) flux densities with GMRT flux densities at 150 MHz helps us to detect sources with extreme spectral indices. Because the majority of high redshift radio sources tend to exhibit steeper radio spectra, deep imaging of the fields with GMRT at 150 MHz will help to detect/discover high redshift radio sources. Our analysis shows that 8% of the sources detected at 150 MHz have very steep spectra with the spectral index exceeding 1.25 (S_? ? ?-?).

  18. Preliminary Results of Polarization Observables T and F in the p-> (?-> ,?0) p Reaction from CLAS

    NASA Astrophysics Data System (ADS)

    Jiang, Hao

    2015-04-01

    The theory which describes the interaction of quarks is Quantum Chromodynamics (QCD), but how quarks are bound inside a nucleon is not yet well understood. Pion photoproduction experiments reveal important information about the nucleon excited states and the dynamics of the quarks within it and thus provide a useful tool in the study of QCD. Detailed information about this reaction can be obtained in experiments which utilize polarized photon beams and polarized targets. Pion photoproduction in the ?p -->?0 p reaction has been measured in the FROST experiment at the Thomas Jefferson National Accelerator Facility. In this experiment circularly polarized photons with energies up to 3 GeV impinged on a transversely polarized frozen-spin target. Final-state protons were detected in the CEBAF Large Acceptance Spectrometer. Preliminary results of the polarization observables T and F have been extracted. The data generally agree with predictions of present partial wave analyses, but also show marked differences. The data will constrain further partial wave analyses and improve the extraction of proton resonance properties. This work is supported in parts by the U.S. National Science Foundation: NSF PHY-1205782.

  19. Statin-induced Myopathy and Ubiquinone Levels in Serum - Results from a Prospective, Observational Study.

    PubMed

    Skilving, Ilona; Acimovic, Jure; Rane, Anders; Ovesj, Marie-Louise; Bjrkhem-Bergman, Linda

    2015-08-01

    It has been suggested that an impaired ubiquinone (Q10) synthesis may be responsible for muscular side effects caused by statins. The primary aim of this study was to investigate whether low Q10 levels in serum could be used as a marker to predict the risk of developing statin-induced myopathy. The secondary aim was to compare the change in Q10 levels during statin treatment and differences between men and women. Serum samples from a prospective, observational study in statin-treated patients who were thoroughly followed regarding muscular symptoms were used. In this cohort, 16 developed myopathy and 126 had no muscular symptoms related to statin treatment. Q10 levels were measured with a novel LC-MS method at baseline and after 2months of statin treatment. Q10 levels showed no correlation with the risk of developing statin-induced myopathy. Individuals with low levels, Q10<200ng/ml, at baseline had no increased risk of developing myopathy. In consistence with earlier reports, we showed that Q10 levels were reduced by 30% during statin treatment. There was no significant difference in the reduction between patients with or without myopathy. Women had approximately 30% lower Q10 levels compared to men both before and after treatment. In this study, there was no association between Q10 levels at baseline and statin-induced muscular side effects during a 2-month follow-up period, and our results indicate that Q10 levels in serum is not a useful marker to predict statin-induced myopathy. PMID:25627869

  20. Interannual variability of global terrestrial primary production: Results of a model driven with satellite observations

    NASA Astrophysics Data System (ADS)

    Goetz, Scott J.; Prince, Stephen D.; Small, Jennifer; Gleason, Arthur C. R.

    2000-08-01

    Interannual variation in terrestrial net primary production (NPP) was modeled using the global production efficiency model (GLO-PEM), a semimechanistic plant photosynthesis and respiration model driven entirely with satellite advanced very high resolution radiometer (AVHRR) observations. The model also estimated a wide range of biophysical variables at 10-day intervals for the period 1982-1989, including air temperature, vapor pressure deficit, soil moisture, biomass, autotrophic respiration, canopy-absorbed photosynthetically active radiation, gross primary production, and light use efficiency. The accuracy of the simulated variables has previously been shown to be within 10-30% of field measurements, depending on the specific variable. We analyze here interannual changes in NPP, which showed large spatial variability (0-1500 gC m-2 yr-1) and trends that differed regionally over the 8-year period. Annually integrated global NPP was found to vary as much as 12% between years and was very sensitive to air temperature. The coefficient of variation in NPP of sparsely vegetated areas (mostly semiarid) on an interannual basis was as much as 80%, whereas densely vegetated areas (broadleaf evergreen and seasonally deciduous forests) varied comparatively little (0-10%). Mean annual NPP of the latter decreased 36 gC m-2 yr-1 over the time series examined. There was extreme seasonal and moderate interannual variation (10-60%) in NPP of middle- to high-latitude regions (temperate and boreal forests) with evidence for a slight trend toward increased values through time (+3 to 12 gC m-2 yr-1). The results indicate significant interannual and regional differences in responses to climate variability, with boreal regions increasing 39 gC m-2 yr-1 compared to a decrease of 116 gC m-2 yr-1 in tropical regions for each 1°C rise in air temperature. We explore a few of the possible reasons for these observations and discuss some of the issues and limitations to the use of the current global AVHRR observational record.

  1. The NIKA 2013-2014 observation campaigns: control of systematic effects and results

    NASA Astrophysics Data System (ADS)

    Catalano, A.; Adam, R.; Adane, A.; Ade, P.; André, P.; Beelen, A.; Belier, B.; Benoît, A.; Bideaud, A.; Billot, N.; Boudou, N.; Bourrion, O.; Calvo, M.; Coiffard, G.; Comis, B.; D'Addabbo, A.; Désert, F.-X.; Doyle, S.; Goupy, J.; Kramer, C.; Leclercq, S.; Macías-Pérez, J.-F.; Martino, J.; Mauskopf, P.; Mayet, F.; Monfardini, A.; Pajot, F.; Pascale, E.; Perotto, L.; Pointecouteau, E.; Ponthieu, N.; Revéret, V.; Ritacco, A.; Rodriguez, L.; Savini, G.; Schuster, K.; Sievers, A.; Tucker, C.; Zylka, R.

    2014-07-01

    The New IRAM KID Array (NIKA) is a dual-band camera operating with frequency multiplexed arrays of Lumped Element Kinetic Inductance Detectors (LEKIDs) cooled to 100 mK. NIKA is designed to observe the intensity and polarisation of the sky at 1.25 and 2.14 mm from the IRAM 30 m telescope. We present the improvements on the control of systematic effects and astrophysical results made during the last observation campaigns between 2012 and 2014.

  2. Reanalysis of mGWAS results and in vitro validation show that lactate dehydrogenase interacts with branched-chain amino acid metabolism.

    PubMed

    Heemskerk, Mattijs M; van Harmelen, Vanessa Ja; van Dijk, Ko Willems; van Klinken, Jan Bert

    2016-01-01

    The assignment of causative genes to noncoding variants identified in genome-wide association studies (GWASs) is challenging. We show how combination of knowledge from gene and pathway databases and chromatin interaction data leads to reinterpretation of published quantitative trait loci for blood metabolites. We describe a previously unidentified link between the rs2403254 locus, which is associated with the ratio of 3-methyl-2-oxobutanoate and alpha-hydroxyisovalerate levels, and the distal LDHA gene. We confirmed that lactate dehydrogenase can catalyze the conversion between these metabolites in vitro, suggesting that it has a role in branched-chain amino acid metabolism. Examining datasets from the ENCODE project we found evidence that the locus and LDHA promoter physically interact, showing that LDHA expression is likely under control of distal regulatory elements. Importantly, this discovery demonstrates that bioinformatic workflows for data integration can have a vital role in the interpretation of GWAS results. PMID:26014429

  3. OBSERVE-5: Observational postmarketing safety surveillance registry of etanercept for the treatment of psoriasis final 5-year results

    PubMed Central

    Kimball, Alexa B.; Rothman, Kenneth J.; Kricorian, Gregory; Pariser, David; Yamauchi, Paul S.; Menter, Alan; Teller, Craig F.; Aras, Girish; Accortt, Neil A.; Hooper, Michele; Rice, Kara Creamer; Gelfand, Joel M.

    2016-01-01

    Background OBSERVE-5 was a 5-year FDA-mandated surveillance registry of psoriasis patients. Objective To assess long-term etanercept safety and effectiveness. Methods Patients with moderate to severe psoriasis enrolled; a single baseline dose of etanercept was required. Key outcome measures included serious adverse events (SAEs), serious infectious events (SIEs), events of medical interest, psoriasis-affected body surface area, physician global assessment, and Dermatology Life Quality Index. Safety outcomes were assessed relative to data from the MarketScan database. Results For 2,510 patients, 5-year cumulative incidence (95% confidence interval [CI]) was 22.2% (20.3%, 24.2%) for SAEs; 6.5% (5.4%, 7.7%) for SIEs; 3.2% (2.3%, 4.1%) for malignancies excluding nonmelanoma skin cancer (NMSC); 3.6% (2.7%, 4.5%) for NMSC; 2.8% (2.0%, 3.6%) for coronary artery disease; 0.7% (0.3%, 1.2%) for psoriasis worsening; 0.2% (0.0%, 0.4%) for CNS demyelinating disorder; 0.1% (0.0%, 0.3%) for lymphoma and for tuberculosis; 0.1% (0.0%, 0.2%) for opportunistic infection and for lupus; 55 fatal events were reported. Rates of malignancies, lymphomas, NMSC, and hospitalization-associated infections were not higher than expected relative to administrative claims data. The percentage of patients rated as clear/almost clear was 12% at baseline, which increased to 51% at month 6 and remained relatively stable throughout 5 years. Limitations No internal comparator group was included; rare events may not have been detected. Conclusion No new safety signals were observed with long-term, real-world etanercept use. PMID:25264239

  4. Evaluation of observation-driven evaporation algorithms: results of the WACMOS-ET project

    NASA Astrophysics Data System (ADS)

    Miralles, Diego G.; Jimenez, Carlos; Ershadi, Ali; McCabe, Matthew F.; Michel, Dominik; Hirschi, Martin; Seneviratne, Sonia I.; Jung, Martin; Wood, Eric F.; (Bob) Su, Z.; Timmermans, Joris; Chen, Xuelong; Fisher, Joshua B.; Mu, Quiaozen; Fernandez, Diego

    2015-04-01

    Terrestrial evaporation (ET) links the continental water, energy and carbon cycles. Understanding the magnitude and variability of ET at the global scale is an essential step towards reducing uncertainties in our projections of climatic conditions and water availability for the future. However, the requirement of global observational data of ET can neither be satisfied with our sparse global in-situ networks, nor with the existing satellite sensors (which cannot measure evaporation directly from space). This situation has led to the recent rise of several algorithms dedicated to deriving ET fields from satellite data indirectly, based on the combination of ET-drivers that can be observed from space (e.g. radiation, temperature, phenological variability, water content, etc.). These algorithms can either be based on physics (e.g. Priestley and Taylor or Penman-Monteith approaches) or be purely statistical (e.g., machine learning). However, and despite the efforts from different initiatives like GEWEX LandFlux (Jimenez et al., 2011; Mueller et al., 2013), the uncertainties inherent in the resulting global ET datasets remain largely unexplored, partly due to a lack of inter-product consistency in forcing data. In response to this need, the ESA WACMOS-ET project started in 2012 with the main objectives of (a) developing a Reference Input Data Set to derive and validate ET estimates, and (b) performing a cross-comparison, error characterization and validation exercise of a group of selected ET algorithms driven by this Reference Input Data Set and by in-situ forcing data. The algorithms tested are SEBS (Su et al., 2002), the Penman- Monteith approach from MODIS (Mu et al., 2011), the Priestley and Taylor JPL model (Fisher et al., 2008), the MPI-MTE model (Jung et al., 2010) and GLEAM (Miralles et al., 2011). In this presentation we will show the first results from the ESA WACMOS-ET project. The performance of the different algorithms at multiple spatial and temporal scales for the 2005-2007 reference period will be disclosed. The skill of these algorithms to close the water balance over the continents will be assessed by comparisons to runoff data. The consistency in forcing data will allow to (a) evaluate the skill of these five algorithms in producing ET over particular ecosystems, (b) facilitate the attribution of the observed differences to either algorithms or driving data, and (c) set up a solid scientific basis for the development of global long-term benchmark ET products. Project progress can be followed on our website http://wacmoset.estellus.eu. REFERENCES Fisher, J. B., Tu, K.P., and Baldocchi, D.D. Global estimates of the land-atmosphere water flux based on monthly AVHRR and ISLSCP-II data, validated at 16 FLUXNET sites. Remote Sens. Environ. 112, 901-919, 2008. Jiménez, C. et al. Global intercomparison of 12 land surface heat flux estimates. J. Geophys. Res. 116, D02102, 2011. Jung, M. et al. Recent decline in the global land evapotranspiration trend due to limited moisture supply. Nature 467, 951-954, 2010. Miralles, D.G. et al. Global land-surface evaporation estimated from satellite-based observations. Hydrol. Earth Syst. Sci. 15, 453-469, 2011. Mu, Q., Zhao, M. & Running, S.W. Improvements to a MODIS global terrestrial evapotranspiration algorithm. Remote Sens. Environ. 115, 1781-1800, 2011. Mueller, B. et al. Benchmark products for land evapotranspiration: LandFlux-EVAL multi- dataset synthesis. Hydrol. Earth Syst. Sci. 17, 3707-3720, 2013. Su, Z. The Surface Energy Balance System (SEBS) for estimation of turbulent heat fluxes. Hydrol. Earth Syst. Sci. 6, 85-99, 2002.

  5. Volatile Transport on Pluto: First Results from the 2013 Observing Season

    NASA Astrophysics Data System (ADS)

    Buratti, B. J.; Dalba, P. A.; Hicks, M.; Chu, D.; O'Neill, A.; Chesley, J. P.

    2013-12-01

    With the New Horizons spacecraft due to encounter Pluto in slightly less than two years, close scrutiny of this dwarf ice planet has begun in earnest. Ground-based observations are especially critical for context and for a larger temporal excursion. Seasonal transport of volatiles should occur on Pluto, and this transport should be detectable through changes in its rotational light curve, once all variations due to viewing geometry have been modeled. Giving the steady increase observed in Pluto's atmospheric pressure over the past two decades, associated sublimation of frost from the surface has likely occurred, as predicted by volatile transport models. Rotational light curves of Pluto through time have been created for static frost models based on images from the Hubble Space Telescope. These models, which account for changes in viewing geometry, have been compared with observed light curves obtained between 1950 and 2013. No evidence for transport was evident prior to 2000. Observations from 2002 (Buie et al., 2010, Astron. J. 139, 1128) and 2007-2008 (Hicks et al. 2008, B.A.A.S. 40, 460) suggest changes in the frost pattern on Pluto's surface. New observations of Pluto's light curve from the 2013 season from Table Mountain Observatory show no evidence for the large transport of volatiles on Pluto's surface. Our data are the first measurement of a large opposition surge on Pluto similar to that seen on other icy bodies. Both Buie et al. (2010) and our observations from the 2012-2013 seasons show that Pluto is becoming more red in color. This observation makes sense if nitrogen is being removed from the surface to uncover a red, photolyzed substrate of methane. Funded by NASA.

  6. Mutual occultations and eclipses of the Galilean satellites of Jupiter in 1997: Astrometric results of observations

    NASA Astrophysics Data System (ADS)

    Emel'Yanov, N. V.; Vashkov'yak, S. N.

    2009-06-01

    In 2006, a complete database of the international campaign on photometric observations of the Galilean satellites of Jupiter in the 1997 epoch of mutual occultations and eclipses was published. Only two thirds of the observations were considered by other authors beforehand. In this study, we have processed the whole observational database with an original technique in order to obtain the astrometric data. We determined 301 relative positions of the satellites from photometric observations performed at 50 observatories around the world. The results are put into a common database of all observations of the natural planetary satellites called the Natural Satellites Data Center (NSDC) available on the Internet site http://www.sai.msu.ru/neb/nss/index.htm . The influence of random and systematic errors on the accuracy of determining the coordinates of satellites has been analyzed. It has been shown that the largest systematic errors are caused by inaccurate elimination of the background of the photometric measurements and by the erroneous data on the albedo of satellites. The actual accuracy of astrometric results is 0.05″ and 0.07″ in right ascension and declination, respectively. New recommendations for photometric observations of satellites during the considered phenomena have been developed in order to avoid the systematic errors.

  7. Results from e-EVN observations of GRS 1915+105

    NASA Astrophysics Data System (ADS)

    Rushton, Anthony; Spencer, R. E.; Strong, M.; Campbell, R. M.; Casey, S.; Fender, R. P.; Garrett, M. A.; Miller-Jones, J. C. A.; Pooley, G. G.; Reynolds, C.; Szomoru, A.; Tudose, V.; Paragi, Z.

    We present results from the first successful open call e-VLBI science run, observing the X-ray binary GRS 1915+105. e-VLBI science allows the rapid production of VLBI radio maps, within hours of an observation rather than weeks. A total of 6 telescopes observing at 5 GHz across the European VLBI Network (EVN) were correlated in real time at the Joint Institute for VLBI in Europe (JIVE). Throughout this, GRS 1915+105 was observed for a total of 5:5 hours, producing 2.8 GB of correlated visibility data. The peak brightness was 10:2 mJy beam^-1, with a total integrated radio flux of 11:1 mJy.

  8. A remote sensing applications update: Results of interviews with Earth Observations Commercialization Program (EOCAP) participants

    NASA Technical Reports Server (NTRS)

    Mcvey, Sally

    1991-01-01

    Earth remote sensing is a uniquely valuable tool for large-scale resource management, a task whose importance will likely increase world-wide through the foreseeable future. NASA research and engineering have virtually created the existing U.S. system, and will continue to push the frontiers, primarily through Earth Observing System (EOS) instruments, research, and data and information systems. It is the researchers' view that the near-term health of remote sensing applications also deserves attention; it seems important not to abandon the system or its clients. The researchers suggest that, like its Landsat predecessor, a successful Earth Observing System program is likely to reinforce pressure to 'manage' natural resources, and consequently, to create more pressure for Earth Observations Commercialization (EOCAP) type applications. The current applications programs, though small, are valuable because of their technical and commercial results, and also because they support a community whose contributions will increase along with our ability to observe the Earth from space.

  9. Results of the new reduction of positional observations of the asteroid Ceres

    NASA Astrophysics Data System (ADS)

    Kuimov, K. V.; Romanova, G. V.; Solov'eva, O. D.; Chazov, V. V.

    2014-07-01

    The results of a new reduction of positional observations of the asteroid Ceres are presented. The observational material was obtained in the State Astronomical Institute using the wide-angle astrograph AFR-1. The interval of photographic observations is 30 years, from August 1956 to May 1986. Measurements of the relative coordinates of stars and the asteroid were submitted electronically. A new model of reduction and a modern catalogue of stellar positions, the reference catalogue Tycho, were used in the calculations. Right ascension and declination of the asteroid at the time of observations were obtained from the International Celestial Reference Frame. The estimate of the mean square error of one measurement is 0.25?.

  10. New results from old data - Lunar photometric anomalies in Wildey and Pohn's 1962 observations

    NASA Technical Reports Server (NTRS)

    Cameron, W. S.

    1980-01-01

    The anomalies in V magnitude in photometric data on lunar features obtained by Wildey and Pohn (1964) are analyzed in the three colors of their UBV observations. The data have been averaged with respect to phase and graphed, and deviations from the average have been tabulated for each color. Sigma equal to or exceeding 3 for V, B-V, and U-B measures are shown on table. These variations are found to be similar to the much larger body of observations of lunar transient phenomena (LTP). The data for 25 features with 25 observations each show that in terms of individual measures the frequency of anomalies is approximately 3%, similar to frequencies obtained in other analyses of LTP data.

  11. Structure and dynamics of the Uranian magnetotail - Results from hot plasma and magnetic field observations

    NASA Technical Reports Server (NTRS)

    Kane, M.; Mauk, B. H.; Keath, E. P.; Krimigis, S. M.

    1991-01-01

    Analysis of Voyager 2 low-energy charged particle and magnetic field data in the Uranian magnetotail show that this system has many features similar to those seen at earth. Isotropization of core magnetosphere 28-43 keV ions has been observed at the trapping boundary upon entry into the magnetotail near L = 17, an effect seen in ion populations at earth and attributed to neutral sheet scattering. An extensive and persistent plasma sheet boundary layer is found to contain field-aligned ion streams with a variety of angular and energetically dispersive effects. Streaming distributions in the magnetotail horn region map to the auroral emission region observed by the Voyager ultraviolet spectrometer. A quiet-time near-tail region is distinguished from a distant disturbed region, where evidence of a substorm is observed. There is evidence suggesting that the distant plasma sheet is not corotating with the planet.

  12. Recent results and current challenges in observations of magnetic fields in Ap/Bp stars

    NASA Astrophysics Data System (ADS)

    Romanyuk, I. I.

    2014-11-01

    We present a survey of observational data of magnetic fields and physical parameters of CP stars acquired over the past 10-15 years. Analyses of new high-precision observations allows us to detect subtle phenomena such as pulsations through light and radial velocity changes, and any vertical stratification of chemical elements in their atmospheres. We derive a relationship between weak anomalies in continuum energy distribution and magnetic-field strength. The relationship was used successfully to search for new magnetic CP stars. An analysis of the profiles of the Stokes Q and U parameters in their spectral lines shows that the observations can be modelled by assuming a field of complex topology. We describe the special case of HD 37776, which cannot be represented by a form of low-order multipoles.

  13. Experimental determination of subjective similarity for pairs of clustered microcalcifications on mammograms: Observer study results

    SciTech Connect

    Muramatsu, Chisako; Li, Qiang; Schmidt, Robert; Suzuki, Kenji; Shiraishi, Junji; Newstead, Gillian; Doi, Kunio

    2006-09-15

    Presentation of images of lesions similar to that of an unknown lesion might be useful to radiologists in distinguishing between benign and malignant clustered microcalcifications on mammograms. Investigators have been developing computerized schemes to select similar images from large databases. However, whether selected images are really similar in appearance is not examined for most of the schemes. In order to retrieve images that are useful to radiologists, the selected images must be similar from radiologists' diagnostic points of view. Therefore, in this study, the data of radiologists' subjective similarity for pairs of clustered microcalcification images were obtained from a number of observers, and the intra- and inter-observer variations and the intergroup correlations were determined to investigate whether reliable similarity ratings by human observers can be determined. Nineteen images of clustered microcalcifications, each of which was paired with six other images, were selected for the observer study. Thus, subjective similarity ratings for 114 pairs of clustered microcalcifications were determined by each observer. Thirteen breast, ten general, and ten nonradiologists participated in the observer study; some of them completed the study multiple times. Although the intraobserver variations for the individual readings and the interobserver variations for pairs of observers were not small, the interobserver agreements were improved by taking the average of readings by the same observers. When the similarity ratings by a number of observers were averaged among the groups of breast, general, and nonradiologists, the mean differences of the ratings between the groups decreased, and good concordance correlations (0.846, 0.817, and 0.785) between the groups were obtained. The result indicates that reliable similarity ratings can be determined by use of this method, and the average similarity ratings by breast radiologists can be considered meaningful and useful for the development and evaluation of a computerized scheme for selection of similar images.

  14. Early results on 67P/Churyumov-Gerasimenko observed by Rosetta/OSIRIS

    NASA Astrophysics Data System (ADS)

    Sierks, H.; Tubiana, C.; Snodgrass, C.; Agarwal, J.; Gttler, C.; Oklay, N.; Vincent, J.; Kppers, M.; Barbieri, C.; Lamy, P.; Rickman, H.; Rodrigo, R.; Koschny, D.; Hviid, S.; Mottola, S.; Osiris Team

    2014-07-01

    67P/Churyumov-Gerasimenko (67P) is the target comet of the ESA Rosetta mission. Launched in 2004, the Rosetta spacecraft woke up on the 20th of January 2014. After 36 months of deep space hibernation, Rosetta is now traveling to rendezvous with the comet at 4.1 au from the Sun, and it will follow 67P along its orbit, investigating how the comet changes and evolves while approaching the Sun. The Optical, Spectroscopic, and Infrared Remote Imaging System OSIRIS (Keller et al., 2007) is the scientific imaging system onboard Rosetta. It comprises the Narrow Angle Camera (NAC) with wavelength range 250--1000 nm and the Wide Angle Camera (WAC) with wavelength range 240--720 nm. The NAC (FOV = 2.202.22 deg) is a system with high spatial resolution that allows an initial detection of the nucleus, studies its structure and rotation from relatively great distances, investigates the mineralogy of the surface, and studies the dust ejection processes. The WAC has much lower spatial resolution but, accordingly, a much wider field of view (about 11.3512.11 deg). This allows observations of the 3-dimensional flow field of dust and gas near the nucleus and, in addition, provides a synoptic view of the whole nucleus. In summary, the WAC would provide long-term monitoring of the entire nucleus from close distances, while the NAC studies the details. The two camera units have been designed as a complementary pair, which, on one hand, addresses the study of the nucleus surface, and on the other hand, investigates the dynamics of the sublimation process. After commissioning in March 2014, OSIRIS took first images of comet 67P and its dust environment. Ground-based observations performed in 2007/08 when 67P was in the same orbital arc as it will be in March/April 2014, show that the comet was already active at 4.3 au inbound and that its behavior was repetitive during the last three apparitions (Snodgrass et al. 2013). We therefore expect to detect early comet activity by OSIRIS in March/April 2014. At this time, Rosetta will be at about 4 million kilometers from the comet and 67P will still be unresolved. We present results about the early cometary activity based on OSIRIS images. Orange-filter images (central wavelength 649.2 nm) will be used to determine the dust environment of 67P, since this wavelength range is quite free from gas emission lines. Moreover, a series of lightcurves will be taken to compare with the existing ones and look for possible changes in the rotational period due to its last perihelion passage.

  15. Revisiting Spitzer Transit Observations with Independent Component Analysis: New Results for Exoplanetary Systems

    NASA Astrophysics Data System (ADS)

    Morello, G.; Waldmann, I. P.; Tinetti, G.; Howarth, I. D.; Micela, G.

    2015-10-01

    Blind source separation techniques are used to reanalyse several exoplanetary transit lightcurves of a few exoplanets recorded with the infrared camera IRAC on board the Spitzer Space Telescope during the "cold" era. These observations, together with observations at other IR wavelengths, are crucial to characterise the atmospheres of the planets. Previous analyses of the same datasets reported discrepant results, hence the necessity of the reanalyses. The method we used here is based on the Independent Component Analysis (ICA) statistical technique, which ensures a high degree of objectivity. The use of ICA to detrend single photometric observations in a self-consistent way is novel in the literature. The advantage of our reanalyses over previous work is that we do not have to make any assumptions on the structure of the unknown instrumental systematics. We obtained for the first time coherent and repeatable results over different epochs for the exoplanets HD189733b and GJ436b[Morello et al.(2014), Morello et al.(2015)]. The technique has been also tested on simulated datasets with different instrument properties, proving its validity in a more general context [Morello et al.(2015b)]. We will present here the technique, and the results of its application to different observations, in addition to the already published ones. A uniform re-analysis of other archive data with this technique will provide improved parameters for a list of exoplanets, and in particular some other results debated in the literature.

  16. Results of Instrument Observations and Adaptive Prediction of Thermoabrasion of Banks of the Vilyui Reservoir

    SciTech Connect

    Velikin, S. A.; Sobol', I. S.; Sobol', S. V.; Khokhlov, D. N.

    2013-11-15

    Quantitative data derived from observations of reformation of the thermoabrasive banks of the Viliyui Reservoir in Yakutia during the service period from 1972 through 2011, and results of analytical prediction of bank formations over the next 20 years for purposes of monitoring the ecological safety of this water body are presented.

  17. Analysis of conservative tracer measurement results using the Frechet distribution at planted horizontal subsurface flow constructed wetlands filled with coarse gravel and showing the effect of clogging processes.

    PubMed

    Dittrich, Ernő; Klincsik, Mihály

    2015-11-01

    A mathematical process, developed in Maple environment, has been successful in decreasing the error of measurement results and in the precise calculation of the moments of corrected tracer functions. It was proved that with this process, the measured tracer results of horizontal subsurface flow constructed wetlands filled with coarse gravel (HSFCW-C) can be fitted more accurately than with the conventionally used distribution functions (Gaussian, Lognormal, Fick (Inverse Gaussian) and Gamma). This statement is true only for the planted HSFCW-Cs. The analysis of unplanted HSFCW-Cs needs more research. The result of the analysis shows that the conventional solutions (completely stirred series tank reactor (CSTR) model and convection-dispersion transport (CDT) model) cannot describe these types of transport processes with sufficient accuracy. These outcomes can help in developing better process descriptions of very difficult transport processes in HSFCW-Cs. Furthermore, a new mathematical process can be developed for the calculation of real hydraulic residence time (HRT) and dispersion coefficient values. The presented method can be generalized to other kinds of hydraulic environments. PMID:26126688

  18. A numerical modeling study of a Montana thunderstorm: 1. Model results versus observations involving nonelectrical aspects

    NASA Astrophysics Data System (ADS)

    Helsdon, John H.; Farley, Richard D.

    1987-05-01

    A recently developed Storm Electrification Model (SEM) has been used to simulate the July 19, 1981, Cooperative Convective Precipitation Experiment (CCOPE) case study cloud. This part of the investigation examines the comparison between the model results and the observations of the actual cloud with respect to its nonelectrical aspects. A timing equivalence is established between the simulation and observations based on an explosive growth phase which was both observed and modeled. This timing equivalence is used as a basis upon which the comparisons are made. The model appears to do a good job of reproducing (in both space and time) many of the observed characteristics of the cloud. These include: (1) the general cloud appearance; (2) cloud size; (3) cloud top rise rate; (4) rapid growth phase; (5) updraft structure; (6) first graupel appearance; (7) first radar echo; (8) qualitative radar range-height indicator evolution; (9) cloud decay; and (10) the location of hydrometers with respect to the updraft/-downdraft structure. Some features that are not accurately modeled are the cloud base height, the maximum liquid water content, and the time from first formation of precipitation until it reaches the ground. While the simulation is not perfect, the faithfulness of the model results to the observations is sufficient to give us confidence that the microphysical processes active in this storm are adequately represented in the model physics. Areas where model improvement is indicated are also discussed.

  19. T-cell lines from 2 patients with adenosine deaminase (ADA) deficiency showed the restoration of ADA activity resulted from the reversion of an inherited mutation.

    PubMed

    Ariga, T; Oda, N; Yamaguchi, K; Kawamura, N; Kikuta, H; Taniuchi, S; Kobayashi, Y; Terada, K; Ikeda, H; Hershfield, M S; Kobayashi, K; Sakiyama, Y

    2001-05-01

    Inherited deficiency of adenosine deaminase (ADA) results in one of the autosomal recessive forms of severe combined immunodeficiency. This report discusses 2 patients with ADA deficiency from different families, in whom a possible reverse mutation had occurred. The novel mutations were identified in the ADA gene from the patients, and both their parents were revealed to be carriers. Unexpectedly, established patient T-cell lines, not B-cell lines, showed half-normal levels of ADA enzyme activity. Reevaluation of the mutations in these T-cell lines indicated that one of the inherited ADA gene mutations was reverted in both patients. At least one of the patients seemed to possess the revertant cells in vivo; however, the mutant cells might have overcome the revertant after receiving ADA enzyme replacement therapy. These findings may have significant implications regarding the prospects for stem cell gene therapy for ADA deficiency. PMID:11313286

  20. How often do German children and adolescents show signs of common mental health problems? Results from different methodological approaches a cross-sectional study

    PubMed Central

    2014-01-01

    Background Child and adolescent mental health problems are ubiquitous and burdensome. Their impact on functional disability, the high rates of accompanying medical illnesses and the potential to last until adulthood make them a major public health issue. While methodological factors cause variability of the results from epidemiological studies, there is a lack of prevalence rates of mental health problems in children and adolescents according to ICD-10 criteria from nationally representative samples. International findings suggest only a small proportion of children with function impairing mental health problems receive treatment, but information about the health care situation of children and adolescents is scarce. The aim of this epidemiological study was a) to classify symptoms of common mental health problems according to ICD-10 criteria in order to compare the statistical and clinical case definition strategies using a single set of data and b) to report ICD-10 codes from health insurance claims data. Methods a) Based on a clinical expert rating, questionnaire items were mapped on ICD-10 criteria; data from the Mental Health Module (BELLA study) were analyzed for relevant ICD-10 and cut-off criteria; b) Claims data were analyzed for relevant ICD-10 codes. Results According to parent report 7.5% (n?=?208) met the ICD-10 criteria of a mild depressive episode and 11% (n?=?305) showed symptoms of depression according to cut-off score; Anxiety is reported in 5.6% (n?=?156) and 11.6% (n?=?323), conduct disorder in 15.2% (n?=?373) and 14.6% (n?=?357). Self-reported symptoms in 11 to 17year olds resulted in 15% (n?=?279) reporting signs of a mild depression according to ICD-10 criteria (vs. 16.7% (n?=?307) based on cut-off) and 10.9% (n?=?201) reported symptoms of anxiety (vs. 15.4% (n?=?283)). Results from routine data identify 0.9% (n?=?1,196) with a depression diagnosis, 3.1% (n?=?6,729) with anxiety and 1.4% (n?=?3,100) with conduct disorder in outpatient health care. Conclusions Statistical and clinical case definition strategies show moderate concordance in depression and conduct disorder in a German national sample. Comparatively, lower rates of children and adolescents with diagnosed mental health problems in the outpatient health care setting support the assumptions that a small number of children and adolescents in need of treatment receive it. PMID:24597565

  1. Continued Volatile Transport on Pluto: First Results from the 2014 Observing Season

    NASA Astrophysics Data System (ADS)

    Buratti, Bonnie J.; Hicks, Michael D.; Dalba, Paul A.; Chu, Devin S.; O'Neill, Ariel; Hillier, John K.; Banholzer, Sophianna

    2014-11-01

    With its high eccentricity and obliquity, Pluto should exhibit seasonal volatile transport on its surface. This transport should be detectable through changes in its historical rotational light curve, once all variations due to viewing geometry have been modelled. Observations of Plutos light curve between 1950 and 1999 suggest a stable albedo pattern. Starting in the early part of this millennium, both new Hubble Space Telescope maps and light curve measurements obtained at JPLs Table Mountain Observatory show evidence of small changes in Plutos distribution of surface albedo (Hicks et al. 2008, B.A.A.S. 40, 460.; Buie et al., 2010, Astron. J. 139, 1128). Supporting possible surface volatile transport is the doubling of Plutos atmospheric pressure over the past two decades (Young et al., 2013, Ap. J. 766, L22). With the New Horizons spacecraft due to encounter Pluto in July 2015, close scrutiny of this dwarf ice planet has begun in earnest. Ground-based observations are especially critical for context and for a larger temporal excursion. Rotational light curves of Pluto have been created in two recent epochs: 2007-2008, and 2012-2014. Both light curves show a smaller amplitude than that expected for a static frost model based on albedo maps from the earliest HST images (Stern et al. 1997, Astron. J. 113, 827). Observations of both Buie et al. (2010) and our own between 2007 and 2014 show that Pluto is becoming redder. This observation makes sense if nitrogen frost is being removed from the surface to uncover a red, photolyzed substrate of methane. Funded by NASA.

  2. Generating two-line elements (TLE) of artificial space objects from optical observations: Preliminary results

    NASA Astrophysics Data System (ADS)

    Rachman, Abdul; Dani, Tiar

    2015-09-01

    Two-line elements (TLE) of an artificial space object can be generated from optical observations with modest instruments. In this preliminary study, ObsReduce was utilized for astrometric analysis to produce positional observations in IOD (Interactive Orbit Determination) format and ELFIND to generate the expected TLE. It turned out that analysis of a single image captured with a point-and-shoot camera in 16 seconds exposure time in a cloudy sky was sufficient to produce a TLE of the International Space Station (ISS) with comparable results in semi-major axis, eccentricity, inclination, RAA Node, and true longitude.

  3. Early Results on Energetic Particle Precipitation Observed by the ABOVE Instrument Array

    NASA Astrophysics Data System (ADS)

    Cully, C. M.; Chaddock, D.; Daniel, C.; Davis, E.; Galts, D.; McGuffin, N.; Quinn, C.; Sheldon, A.; Wilson, C.

    2014-12-01

    ABOVE, the Array for Broadband Observations of VLF/ELF Emissions, is a network of radio instruments located across western Canada. The instruments monitor natural and artificial electromagnetic radiation in the frequency range from 200 Hz to 75 kHz. The primary scientific focus is on energetic particle precipitation: we infer precipitation into the atmosphere based on the observed amplitude and phase of remotely transmitted artificial signals, and simultanesouly monitor natural whistler-mode waves (chorus and hiss) that drive the precipitation. Instrument deployment began during the summer of 2014. We report here on the instrument design and the first results.

  4. Speckle interferometry of magnetic stars with the BTA. II. Results of 2010-2012 observations

    NASA Astrophysics Data System (ADS)

    Rastegaev, D. A.; Balega, Yu. Yu.; Dyachenko, V. V.; Maksimov, A. F.; Malogolovets, E. V.

    2014-07-01

    We present the results of speckle interferometric observations of 156 stars possessing global magnetic fields, carried out with the 6-m BTA telescope of the Special Astrophysical Observatory. Virtually all stars were observed between 2010 and 2012. Thirty-four stars were resolved into individual components (31 double and 3 triple), of which 14 binary systems (BD+41?43, HD2887, HD30466, HD36540, HD36955, HD37479, HD61045, HD89069, HD144334, HD164258, HD349321, HD343872, HD184471, HD196691) and 2 triple systems (HD37140, HD338226) were for the first time resolved by the astrometric method.

  5. Observation VLBI Session RAPL02. the Results of the Data Processing

    NASA Astrophysics Data System (ADS)

    Chuprikov, A. A.

    Results of processing of data of a VLBI experiment titled RAPL02 are presented. These observations were made in 2011 February with 5 antennas. All 3 antennas of Petersberg's Institute of Applied Astronomy (IAA) were used in this session. These were antennae in Svetloe, in Zelenchuck, and in Badary. Additionally, a 22-m antenna in Puschino as well as a 32-m antenna in Medicina (Italy) were also included into observations. The raw data correlation was made at the software correlator of Astro Space Center. The secondary data processing was made for 3 quasars, 3C273, 3C279, and 3C286.

  6. Photographic zenith tube of the Zvenigorod INASAN Observatory - Processing method and observation results

    NASA Astrophysics Data System (ADS)

    Yurov, E. A.

    1992-10-01

    A method for the reduction of PZT plates which has been used at the Zvenigorod INASAN Observatory since 1986 is described. The formulas used for computing the coordinates of the stellar image in the focal plane at the midpoint of the exposure are correct to 0.0024 arcsec. Observations from February 1986 to October 1988 are compared with data of BIH and IERS, and the results of the comparison are used to compute the amplitudes of the annual terms of nonpolar variations in the observed latitudes and Delta(UTI).

  7. Very-long-baseline radio interferometry (VLBI) observations of gamma-ray blazars: results from millimeter-VLBI observations.

    PubMed Central

    Krichbaum, T P; Britzen, S; Standke, K J; Witzel, A; Schalinski, C J; Zensus, J A

    1995-01-01

    VLBI observations of the extremely gamma-bright blazar PKS 0528+134 at 8, 22, 43, and 86 GHz reveal a strongly bent one-sided-core jet structure with at least three moving and two apparently stationary jet components. At the highest observing frequencies the brightest and most compact jet component (the VLBI core) is unresolved with an upper limit to its size of approximately 50 microarcsec corresponding to approximately 0.2 parsec [H0 = 100 km.s-1.Mpc-1 (megaparsec-1), q0 = 0.5, where H0 is Hubble constant and q0 is the deceleration parameter]. Two 86-GHz VLBI observations performed in 1993.3 and 1994.0 reveal a new jet component emerging with superluminal speed from the core. Linear back-extrapolation of its motion yields strong evidence that the ejection of this component is related to an outburst in the millimeter regime and a preceding intense flare of the gamma-flux density observed in early 1993. This and the radio/optical "light curves" and VLBI data for two other sources (S5 0836+710 and 3C 454.3) suggest that the observed gamma-radiation might be Doppler-boosted and perhaps is closely related to the physical processes acting near the "base" of the highly relativistic jets observed in quasars. PMID:11607602

  8. Transgene silencing of the Hutchinson-Gilford progeria syndrome mutation results in a reversible bone phenotype, whereas resveratrol treatment does not show overall beneficial effects.

    PubMed

    Strandgren, Charlotte; Nasser, Hasina Abdul; McKenna, Toms; Koskela, Antti; Tuukkanen, Juha; Ohlsson, Claes; Rozell, Bjrn; Eriksson, Maria

    2015-08-01

    Hutchinson-Gilford progeria syndrome (HGPS) is a rare premature aging disorder that is most commonly caused by a de novo point mutation in exon 11 of the LMNA gene, c.1824C>T, which results in an increased production of a truncated form of lamin A known as progerin. In this study, we used a mouse model to study the possibility of recovering from HGPS bone disease upon silencing of the HGPS mutation, and the potential benefits from treatment with resveratrol. We show that complete silencing of the transgenic expression of progerin normalized bone morphology and mineralization already after 7 weeks. The improvements included lower frequencies of rib fractures and callus formation, an increased number of osteocytes in remodeled bone, and normalized dentinogenesis. The beneficial effects from resveratrol treatment were less significant and to a large extent similar to mice treated with sucrose alone. However, the reversal of the dental phenotype of overgrown and laterally displaced lower incisors in HGPS mice could be attributed to resveratrol. Our results indicate that the HGPS bone defects were reversible upon suppressed transgenic expression and suggest that treatments targeting aberrant progerin splicing give hope to patients who are affected by HGPS. PMID:25877214

  9. Boundary Layer Vertical Exchange Processes and the Mass Budget of Ozone: Observations and Model Results

    SciTech Connect

    Berkowitz, Carl M.; Fast, Jerome D.; Easter, Richard C.

    2000-06-16

    An Eulerian chemical model is used to assess the relative importance of a variety of processes associated with producing high surface ozone episodes during selected periods of the NARSTO 1995 field campaign over the northeastern United States. A comparison of the observed and predicted hourly surface ozone mixing ratios showed that the model qualitatively reproduced the observed ozone trends over the northeastern U.S. The model, however, over-predicted the surface concentrations by 10 to 15 ppb. The simulated mass budget tendency terms are compared for days with low ozone values immediately followed by days with high values. The later days showed observed and simulated ozone mixing ratios aloft to be of order twice that found on preceding days, although the associated chemical mix appeared to have relatively little potential for the subsequent generation of "new" ozone. Under conditions of shallow mixing over urban regions, simulated surface ozone production rates were negative (a net loss) throughout much of the day with convective mixing bringing newly produced ozone from aloft to the surface. It is noted that surface ozone levels appeared to be relatively insensitive to mixing layer growth rates.

  10. PHOTOMETRY OF VARIABLE STARS FROM DOME A, ANTARCTICA: RESULTS FROM THE 2010 OBSERVING SEASON

    SciTech Connect

    Wang, Lingzhi; Zhu, Zonghong; Macri, Lucas M.; Wang, Lifan; Ashley, Michael C. B.; Lawrence, Jon S.; Luong-Van, Daniel; Storey, John W. V.; Cui, Xiangqun; Feng, Long-Long; Gong, Xuefei; Liu, Qiang; Shang, Zhaohui; Yang, Huigen; Yang, Ji; Yuan, Xiangyan; Zhou, Xu; Zhu, Zhenxi; Pennypacker, Carl R.; York, Donald G.

    2013-12-01

    We present results from a season of observations with the Chinese Small Telescope ARray, obtained over 183 days of the 2010 Antarctic winter. We carried out high-cadence time-series aperture photometry of 9125 stars with i ?< 15.3 mag located in a 23 deg{sup 2} region centered on the south celestial pole. We identified 188 variable stars, including 67 new objects relative to our 2008 observations, thanks to broader synoptic coverage, a deeper magnitude limit, and a larger field of view. We used the photometric data set to derive site statistics from Dome A. Based on two years of observations, we find that extinction due to clouds at this site is less than 0.1 and 0.4 mag during 45% and 75% of the dark time, respectively.

  11. Magnetic Sphincter Augmentation for Gastroesophageal Reflux at 5 Years: Final Results of a Pilot Study Show Long-Term Acid Reduction and Symptom Improvement

    PubMed Central

    Saino, Greta; Bonavina, Luigi; Lipham, John C.; Dunn, Daniel

    2015-01-01

    Abstract Background: As previously reported, the magnetic sphincter augmentation device (MSAD) preserves gastric anatomy and results in less severe side effects than traditional antireflux surgery. The final 5-year results of a pilot study are reported here. Patients and Methods: A prospective, multicenter study evaluated safety and efficacy of the MSAD for 5 years. Prior to MSAD placement, patients had abnormal esophageal acid and symptoms poorly controlled by proton pump inhibitors (PPIs). Patients served as their own control, which allowed comparison between baseline and postoperative measurements to determine individual treatment effect. At 5 years, gastroesophageal reflux disease (GERD)-Health Related Quality of Life (HRQL) questionnaire score, esophageal pH, PPI use, and complications were evaluated. Results: Between February 2007 and October 2008, 44 patients (26 males) had an MSAD implanted by laparoscopy, and 33 patients were followed up at 5 years. Mean total percentage of time with pH <4 was 11.9% at baseline and 4.6% at 5 years (P?shows the relative safety and efficacy of magnetic sphincter augmentation for GERD. PMID:26437027

  12. Results of Space Debris Survey Observations on Highly-Eccentric MEO Orbits

    NASA Astrophysics Data System (ADS)

    Hinze, Andreas; Schildknecht, T.; Flohrer, T.; Krag, H.

    2013-08-01

    Optical surveys for space debris in high-altitude orbits have been conducted since more than ten years. First observation strategies and processing techniques were successfully developed for the geostationary ring (GEO). The observations scenarios were adjusted for observations in the geostationary transfer orbit (GTO) and in the medium Earth orbit (MEO). After the already investigated circular MEO orbits of the GPS and GLONASS constellations the Astronomical Institute of the University of Bern (AIUB) developed survey and follow-up strategies for the systematically search of space debris in highly-eccentric orbits in the MEO region, in particular in Molniya-type orbits. Several breakup events and deliberate fragmentations are known to have taken place in such orbits. The AIUB performed several survey campaigns between January 2013 and April 2013 to search for debris objects in this MEO region. The optical observations were conducted in the framework of an ESA study using ESA's Space Debris Telescope (ESASDT) the 1-m Zeiss telescope located at the Optical Ground Station (OGS) at the Teide Observatory at Tenerife, Spain. The results from the different observation campaigns will be presented.

  13. Comparisons of Observations with Results from 3D Simulations and Implications for Predictions of Ozone Recovery

    NASA Technical Reports Server (NTRS)

    Douglass, Anne R.; Stolarski, Richard S.; Strahan, Susan E.; Steenrod, Stephen D.; Polarsky, Brian C.

    2004-01-01

    Although chemistry and transport models (CTMs) include the same basic elements (photo- chemical mechanism and solver, photolysis scheme, meteorological fields, numerical transport scheme), they produce different results for the future recovery of stratospheric ozone as chlorofluorcarbons decrease. Three simulations will be contrasted: the Global Modeling Initiative (GMI) CTM driven by a single year\\'s winds from a general circulation model; the GMI CTM driven by a single year\\'s winds from a data assimilation system; the NASA GSFC CTM driven by a winds from a multi-year GCM simulation. CTM results for ozone and other constituents will be compared with each other and with observations from ground-based and satellite platforms to address the following: Does the simulated ozone tendency and its latitude, altitude and seasonal dependence match that derived from observations? Does the balance from analysis of observations? Does the balance among photochemical processes match that expected from observations? Can the differences in prediction for ozone recovery be anticipated from these comparisons?

  14. OBSERVATIONS OF BINARY STARS WITH THE DIFFERENTIAL SPECKLE SURVEY INSTRUMENT. I. INSTRUMENT DESCRIPTION AND FIRST RESULTS

    SciTech Connect

    Horch, Elliott P.; Veillette, Daniel R.; Shah, Sagar C.; O'Rielly, Grant V.; Baena Galle, Roberto; Van Altena, William F. E-mail: drv@usno.navy.mil E-mail: gorielly@umassd.edu E-mail: william.vanaltena@yale.edu

    2009-06-15

    First results of a new speckle imaging system, the Differential Speckle Survey Instrument, are reported. The instrument is designed to take speckle data in two filters simultaneously with two independent CCD imagers. This feature results in three advantages over other speckle cameras: (1) twice as many frames can be obtained in the same observation time which can increase the signal-to-noise ratio for astrometric measurements, (2) component colors can be derived from a single observation, and (3) the two colors give substantial leverage over atmospheric dispersion, allowing for subdiffraction-limited separations to be measured reliably. Fifty-four observations are reported from the first use of the instrument at the Wisconsin-Indiana-Yale-NOAO 3.5 m Telescope{sup 9}The WIYN Observatory is a joint facility of the University of Wisconsin-Madison, Indiana University, Yale University, and the National Optical Astronomy Observatories. in 2008 September, including seven components resolved for the first time. These observations are used to judge the basic capabilities of the instrument.

  15. Results of observations of the Eta Aquarid and Orionid meteor showers in 1980-1984

    NASA Technical Reports Server (NTRS)

    Hajduk, A.

    1987-01-01

    The main characteristics of meteor showers associated with Comet Halley were derived from the most recent radar observations carried out at the Ondrejov Astronomical Observatory during the periods of May 1 to 10 and October 15 to 30. The activity variations, the positions of activity maxima, the size distribution of particles, the particle flux variation within the stream and other characteristics were determined and compared with other results.

  16. IRAS observations show that the Earth is embedded in a solar ring of asteroidal dust particles in resonant lock with the planet

    NASA Astrophysics Data System (ADS)

    Dermott, Stanley F.; Jayaraman, S.; Xu, Y.-L.; Liou, J.-C.

    We have analyzed all the infrared observations of the zodiacal cloud obtained in 1983 by the Infrared Astronomical Satellite (IRAS) and shown that when viewed at a constant elongation angle of 90 degrees, the elliptic brightness of the cloud is systematically greater by approx. 3 percent in the trailing direction than in the leading direction. This asymmetry is observed at all times of the year and in all three of the IRAS wavebands in which the zodiacal cloud is clearly observed. The orbits of cometary particles are highly eccentric and these particles are unlikely to be trapped in corotational resonances. Thus, the IRAS observations are evidence that the Earth is embedded in a ring of asteroidal particles. Similar rings are expected to be associated with Mars and Venus. The existence of asteroidal families and their associated dust bands (also discovered by IRAS) are evidence that the asteroid belt is a significant and maybe the dominant source of dust in the zodiacal cloud. These new observations give quantitative information both on the rate of transport of asteroidal dust to the Earth and on the rate of grinding down of the asteroid belt. Without resonant trapping most dust particles spiral past the Earth without striking the planet. However, most particles trapped in resonances are released from these resonances due to close encounter with the Earth. Thus, the ring may act as a funnel through which asteroidal particles are deposited in the Earth's atmosphere. This could have implications for the efficiency of the transport of carbonaceous material from the asteroid belt to the Earth and for the origin of life on the planet.

  17. IRAS observations show that the Earth is embedded in a solar ring of asteroidal dust particles in resonant lock with the planet

    NASA Technical Reports Server (NTRS)

    Dermott, Stanley F.; Jayaraman, S.; Xu, Y.-L.; Liou, J.-C.

    1994-01-01

    We have analyzed all the infrared observations of the zodiacal cloud obtained in 1983 by the Infrared Astronomical Satellite (IRAS) and shown that when viewed at a constant elongation angle of 90 degrees, the elliptic brightness of the cloud is systematically greater by approx. 3 percent in the trailing direction than in the leading direction. This asymmetry is observed at all times of the year and in all three of the IRAS wavebands in which the zodiacal cloud is clearly observed. The orbits of cometary particles are highly eccentric and these particles are unlikely to be trapped in corotational resonances. Thus, the IRAS observations are evidence that the Earth is embedded in a ring of asteroidal particles. Similar rings are expected to be associated with Mars and Venus. The existence of asteroidal families and their associated dust bands (also discovered by IRAS) are evidence that the asteroid belt is a significant and maybe the dominant source of dust in the zodiacal cloud. These new observations give quantitative information both on the rate of transport of asteroidal dust to the Earth and on the rate of grinding down of the asteroid belt. Without resonant trapping most dust particles spiral past the Earth without striking the planet. However, most particles trapped in resonances are released from these resonances due to close encounter with the Earth. Thus, the ring may act as a funnel through which asteroidal particles are deposited in the Earth's atmosphere. This could have implications for the efficiency of the transport of carbonaceous material from the asteroid belt to the Earth and for the origin of life on the planet.

  18. Cute SCIDAR: presentation of the new Canarian instrument and first observational results

    NASA Astrophysics Data System (ADS)

    Hoegemann, Claudia K.; Chueca, Sergio; Delgado, Jose M.; Fuensalida, Jesus J.; Garcia-Lorenzo, Begona; Mendizabal, Esteban G.; Reyes, Marcos; Verde, Manuel; Vernin, Jean

    2004-10-01

    We present a new generation SCIDAR instrument that is a fully automatically controlled device with a user-friendly interface. Alignment and observation are reduced to easy and rapid handling without the effort operating in the dome. This instrument is installed in the Jacobus Kapteyn Telescope on La Palma. We describe our progress from prototype to second generation instrument, emphasizing the design and the software for Cute SCIDAR, and show profiles from systematic monitoring using the prototype instrument on Tenerife and Cute SCIDAR on La Palma.

  19. High energy nucleus-nucleus collisions at CERN: Signatures, physical observables and experimental results

    SciTech Connect

    Harris, J.W.

    1988-02-01

    Experimental results on high energy nucleus-nucleus collisions have become available with the recent experiments at CERN utilizing 200 GeV/n oxygen and sulfur beams. Physics motivations for these experiments are presented: a description of predicted signatures for possible formation of a quark-gluon plasma and physical observables that are expected to provide important information for understanding the dynamics of these collisions. A presentation will be made of some of the first experimental results to emerge from this new field. 28 refs., 9 figs.

  20. Observed galaxy number counts on the lightcone up to second order: I. Main result

    SciTech Connect

    Bertacca, Daniele; Maartens, Roy; Clarkson, Chris E-mail: roy.maartens@gmail.com

    2014-09-01

    We present the galaxy number overdensity up to second order in redshift space on cosmological scales for a concordance model. The result contains all general relativistic effects up to second order that arise from observing on the past light cone, including all redshift effects, lensing distortions from convergence and shear, and contributions from velocities, Sachs-Wolfe, integrated SW and time-delay terms. This result will be important for accurate calculation of the bias on estimates of non-Gaussianity and on precision parameter estimates, introduced by nonlinear projection effects.

  1. Blending Model Results With Observations in the SBC/SMB Study

    NASA Astrophysics Data System (ADS)

    Wang, D.; Ohashi, K.

    2002-12-01

    The 1993-1999 Santa Barbara V Santa Maria Basin (SBC/SMB) circulation study, conducted by the Center for Coastal Study of the Scripps Institution of Oceanography, represents a major research effort towards designing a coastal ocean observing system (COOS). During the 6-year period, at any time there were always about a dozen current meter and temperature moorings maintained in the study area. The moored measurements have continuous spatial and temporal coverage and are most trustworthy (compared to, say, shipboard observation and remote sensing), and thus are ideally suited as the \\x9Dabsolute reference in describing ocean states. On the other hand, the mooring observations are point measurements, and it is unlikely that the moored data alone will ever have adequate spatial resolution in a COOS. There is need for complementary data. Coastal circulation models could play a crucial role in filling this gap. Examples of using coastal ocean models in the SBC/SMB study to obtain ocean state estimation will be presented. A coastal ocean model typically is driven by the atmospheric forcing (which must be specified over the entire model domain) and the mass and momentum exchange across \\x9Dopen boundaries. In this study the atmospheric forcing is derived from a dozen met buoy observations plus numerous coastal weather stations collected during the SBC/SMB study. The need to specify open-ocean water mass exchange is circumvented by assimilating the moored temperature data. The possibility of impinging open-ocean eddy, however, is ruled out. Two research issues are addressed. First, an attempt is made to blend the model results with moored velocity observations. Second, the impact of data assimilation on model results is examined. These two issues, one dealing with the initialization in ocean forecasts and nowcasts and the other with the sampling design, are fundamental to any COOS. The comprehensive SBC/SMB study affords an excellent opportunity for a COOS feasibility study.

  2. The LXD-mode Main-Belt/NEO Observing Program (LMNOP): Results

    NASA Astrophysics Data System (ADS)

    Rivkin, A.; Howell, E.; Emery, J.

    2014-07-01

    The spectral region beyond 2.5 ? m is rich with spectral features due to OH, water, and organic materials. For many low-albedo objects, it hosts the only detectable absorption bands. For this reason, astronomical observations of asteroids at these wavelengths are critical to understanding their nature, even though such observations can be difficult due to the Earth's atmosphere [1]. Since 2002, we have been obtaining data in the 2--4 ? m region using the SpeX instrument on the IRTF in ''LXD mode'' [2]. While not originally designed as a survey, we call the collection of individual projects that we have completed over the years the ''LXD-mode Main- belt/NEO Observing Program'' (LMNOP). At the time of the upgrade of the SpeX instrument earlier in 2014, 390 observations of 210 different asteroids have been observed in the LMNOP. We have focused on C-complex asteroids (53 % of targets), but the survey also includes significant numbers of targets in the X complex (24 %) and S complex (11 %). The SpeX upgrade, with an associated break in observing and a need to change the reduction pipeline for future data, marks a convenient time to mark the end of this phase of the LMNOP. The data collected has already been used to determine the surface compositional variation on Ceres [3-4], Lutetia [5], and Vesta [6], and to discover water ice frost on the surface of Themis [7]. Analysis is now moving forward into studies of compositional variation on Pallas and Hygiea, among other objects. The data is also being analyzed to study the links between the Ch-class asteroids and the CM meteorites, and to calculate the amount of water/OH implied by the asteroid spectra. We will present results from the LMNOP dataset, including in-depth studies of individual objects, interpretations of taxonomic groups, and the beginnings of a taxonomic system in the 3-? m range itself.

  3. Third-Year Results from the Circumarctic Lakes Observation Network (CALON) Project

    NASA Astrophysics Data System (ADS)

    Hinkel, K. M.; Arp, C. D.; Beck, R. A.; Eisner, W. R.; Frey, K. E.; Grosse, G.; Jones, B. M.; Kim, C.; Lenters, J. D.; Liu, H.; Townsend-Small, A.

    2014-12-01

    Since 2012, 60 lakes in northern Alaska have been instrumented under the auspices of CALON, a project designed to document landscape-scale variability in physical and biogeochemical processes of Arctic lakes in permafrost terrain. The network has ten observation nodes along two latitudinal transects extending from the Arctic Ocean inland some 200 km to the Brooks Range foothills. At each node, a meteorological station is deployed, and six representative lakes of differing area and depth are instrumented and sampled at different intensity levels to collect basic field measurements. In April, sensors measuring water temperature and depth are deployed through the ice in each lake, ice and snow thickness recorded, and water samples are collected. Data are downloaded, lakes re-sampled, and bathymetric surveys are conducted in August. In 2014, the snow cover on inland lakes was thinner than in previous years but thicker on lakes located near the coast. Lake ice was generally thinner near the coast, but the difference diminished inland. Winters (Oct-March) have been progressively warmer over the 3-year period, which partially explains the thinner lake ice that formed in 2013-14. Lakes are typically well-mixed and largely isothermal, with minor thermal stratification occurring in deeper lakes during calm, sunny periods. These regional lake and meteorological data sets, used in conjunction with satellite imagery, supports the wind-driven lake circulation model for the origin of thermokarst lakes. Results of biogeochemical analyses of lake waters generally show notably higher concentrations of cations/anions, chromophoric dissolved organic matter, and chlorophyll-a during April as compared with August. Dissolved methane concentrations are also much higher under ice than in open water during summer, although all lakes are a source of atmospheric methane. Interviews with indigenous elders in Anaktuvuk Pass indicate that mountain lakes are drying up. During the 2014 breakup period, 350 entrants participated in the 2nd Annual Toolik Lake Ice Classic including elementary school children, the general public, and international researchers. Ice off occurred on 23 June, and 11 people correctly guessed this day. All field data is archived at A-CADIS, and further information is at www.arcticlakes.org.

  4. Five-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Data Processing, Sky Maps, and Basic Results

    NASA Technical Reports Server (NTRS)

    Weiland, J.L.; Hill, R.S.; Odegard, 3.; Larson, D.; Bennett, C.L.; Dunkley, J.; Jarosik, N.; Page, L.; Spergel, D.N.; Halpern, M.; Meyer, S.S.; Tucker, G.S.; Wright, E.L.

    2008-01-01

    The Wilkinson Microwave Anisotropy Probe (WMAP) is a Medium-Class Explorer (MIDEX) satellite aimed at elucidating cosmology through full-sky observations of the cosmic microwave background (CMB). The WMAP full-sky maps of the temperature and polarization anisotropy in five frequency bands provide our most accurate view to date of conditions in the early universe. The multi-frequency data facilitate the separation of the CMB signal from foreground emission arising both from our Galaxy and from extragalactic sources. The CMB angular power spectrum derived from these maps exhibits a highly coherent acoustic peak structure which makes it possible to extract a wealth of information about the composition and history of the universe. as well as the processes that seeded the fluctuations. WMAP data have played a key role in establishing ACDM as the new standard model of cosmology (Bennett et al. 2003: Spergel et al. 2003; Hinshaw et al. 2007: Spergel et al. 2007): a flat universe dominated by dark energy, supplemented by dark matter and atoms with density fluctuations seeded by a Gaussian, adiabatic, nearly scale invariant process. The basic properties of this universe are determined by five numbers: the density of matter, the density of atoms. the age of the universe (or equivalently, the Hubble constant today), the amplitude of the initial fluctuations, and their scale dependence. By accurately measuring the first few peaks in the angular power spectrum, WMAP data have enabled the following accomplishments: Showing the dark matter must be non-baryonic and interact only weakly with atoms and radiation. The WMAP measurement of the dark matter density puts important constraints on supersymmetric dark matter models and on the properties of other dark matter candidates. With five years of data and a better determination of our beam response, this measurement has been significantly improved. Precise determination of the density of atoms in the universe. The agreement between the atomic density derived from WMAP and the density inferred from the deuterium abundance is an important test of the standard big bang model. Determination of the acoustic scale at redshift z = 1090. Similarly, the recent measurement of baryon acoustic oscillations (BAO) in the galaxy power spectrum (Eisenstein et al. 2005) has determined the acoustic scale at redshift z approx. 0.35. When combined, these standard rulers accurately measure the geometry of the universe and the properties of the dark energy. These data require a nearly flat universe dominated by dark energy consistent with a cosmological constant. Precise determination of the Hubble Constant, in conjunction with BAO observations. Even when allowing curvature (Omega(sub 0) does not equal 1) and a free dark energy equation of state (w does not equal -1), the acoustic data determine the Hubble constant to within 3%. The measured value is in excellent agreement with independent results from the Hubble Key Project (Freedman et al. 2001), providing yet another important consistency test for the standard model. Significant constraint of the basic properties of the primordial fluctuations. The anti-correlation seen in the temperature/polarization (TE) correlation spectrum on 4deg scales implies that the fluctuations are primarily adiabatic and rule out defect models and isocurvature models as the primary source of fluctuations (Peiris et al. 2003).

  5. Overview of the first HyMeX Special Observation Period over Italy: observations and model results

    NASA Astrophysics Data System (ADS)

    Ferretti, R.; Pichelli, E.; Gentile, S.; Maiello, I.; Cimini, D.; Davolio, S.; Miglietta, M. M.; Panegrossi, G.; Baldini, L.; Pasi, F.; Marzano, F. S.; Zinzi, A.; Mariani, S.; Casaioli, M.; Bartolini, G.; Loglisci, N.; Montani, A.; Marsigli, C.; Manzato, A.; Pucillo, A.; Ferrario, M. E.; Colaiuda, V.; Rotunno, R.

    2013-09-01

    During the first Hymex campaign (5 September-6 November 2012) referred to as Special Observation Period (SOP-1), dedicated to heavy precipitation events and flash floods in Western Mediterranean, three Italian hydro-meteorological monitoring sites were activated: Liguria-Tuscany, North-Eastern Italy and Central Italy. The extraordinary deployment of advanced instrumentation, including instrumented aircrafts, and the use of several different operational weather forecast models has allowed an unprecedented monitoring and analysis of high impact weather events around the Italian hydro-meteorological sites. This activity has seen the strict collaboration between the Italian scientific and operational communities. In this paper, an overview of the Italian organization during the SOP-1 is provided, and selected Intensive Observation Periods (IOPs) are described. A significant event for each Italian target area is chosen for this analysis: IOP2 (12-13 September 2012) in North-Eastern Italy, IOP13 (15-16 October 2012) in Central Italy and IOP19 (3-5 November 2012) in Liguria and Tuscany. For each IOP the meteorological characteristics, together with special observations and weather forecasts, are analyzed with the aim of highlighting strengths and weaknesses of the forecast modeling systems. Moreover, using one of the three events, the usefulness of different operational chains is highlighted.

  6. Results of a Deep Chandra Observation of the Crab Nebula and Pulsar

    NASA Technical Reports Server (NTRS)

    Weisskopf, M. C.; Becker, W.; Elsner, R.; Kahn, S.; Kolodziejczak, J.; Murray, S.; ODell, S.; Paerels, F.; Shibazaki, N.; Swartz, D.

    2000-01-01

    The Crab Nebula and pulsar were observed for a total of 150 ksec with the LETG/HRC-S combination aboard the Chandra X-Ray Observatory in 2000, January. One of the principal aims of the experiment was to study the emission of from the pulsar as a function of pulse phase. Neutron stars are believed to be formed with core temperatures of T(sub c) approx. 10(sup 11) K. As the pulsar is the youngest known neutron star with an age of only 940 yrs, it should be possible to observe thermal emission from the hot stellar surface which in turn constrains equations of state. The pulsar, on the other hand, is a powerful non-thermal emitter, powering an X-ray bright synchrotron nebula which, in Einstein and ROSAT observations, overshadowed the fainter thermal surface emission. Making use of the high angular resolution provided by Chandra we were able to detect X-rays from the Crab-pulsar at all pulse phases. We discuss whether this detection is indeed of thermal emission or of a faint synchrotron component of the pulsed emission from the magnetosphere. We further report on dynamical effects observed in the pulsar-wind outflow and the analysis of the LETG spectral data, especially near the oxygen edge. The results of the spectral analysis has interesting implications for the composition of the interstellar medium.(c) 2000.: American Astronomical Society. All rights reserved

  7. Results of a Deep Chandra Observation of the Crab Nebula and Pulsar

    NASA Technical Reports Server (NTRS)

    Weisskopf, M. C.; Becker, W.; Elsner, R.; Kahn, S.; Kolodziejczak, J.; Murray, S.; ODell, S.; Paerels, F.; Shibazaki, N.; Swartz, D.; Rose, M. Franklin (Technical Monitor)

    2000-01-01

    The Crab Nebula and pulsar were observed for a total of 150 ksec with the LETG/HRC-S combination aboard the Chandra X-Ray Observatory in 2000, January. One of the principal aims of the experiment was to study the emission of from the pulsar as a function of pulse phase. Neutron stars are believed to be formed with core temperatures of 10(exp 11). As the pulsar is the youngest known neutron star with an age of only 940 yrs, it should be possible to observe thermal emission from the hot stellar surface which in turn constrains equations of state. The pulsar, on the other hand, is a powerful non-thermal emitter, powering an X-ray bright synchrotron nebula which, in Einstein and ROSAT observations, overshadowed the fainter thermal surface emission. Making use of the high angular resolution provided by Chandra we were able to detect X-rays from the Crab-pulsar at all pulse phases. We discuss whether this detection is indeed of thermal emission or of a faint synchrotron component of the pulsed emission from the magnetosphere. We further report on dynamical effects observed in the pulsar-wind outflow and the analysis of the LETG spectral data, especially near the oxygen edge. The results of the spectral analysis has interesting implications for the composition of the interstellar medium.

  8. Magnetic reconnection signatures in the solar atmosphere: results from multi-wavelength observations

    NASA Astrophysics Data System (ADS)

    Zuccarello, F.; Guglielmino, S. L.; Romano, P.

    In the solar atmosphere magnetic reconnection is invoked as the main mechanism causing very energetic events (1028 - 1032 erg), like flares and coronal mass ejections, as well as other less energetic phenomena, like microflares, X-ray jets and chromospheric surges. In the last decade, thanks to high spatial resolution, multi-wavelength observations carried out by both ground-based telescopes (THEMIS, SST, VTT, DST) and space-born satellites (SOHO, TRACE, RHESSI, HINODE), it has been possible to study these phenomena and several signatures of the occurrence of magnetic reconnection have been singled out. In this paper, we describe some results obtained from the analysis of multi-wavelength observations carried out in the last years, with special emphasis on those events that were characterized by plasma outflows from the reconnection site. The events here discussed are relevant to some active regions observed on the Sun, characterized by the interaction of different bundles of magnetic flux tubes, as a consequence of phenomena of emergence of new magnetic flux from the subphotospheric layers and/or of cancellation of magnetic fragments. We report on these phenomena in order to give a contribution to the possibility to find a similarity with jets observed in AGNs.

  9. Observing the North Atlantic MOC: RAPID programme initial results and future plans

    NASA Astrophysics Data System (ADS)

    Srokosz, M.; Byfield, V.

    2006-12-01

    In order to determine whether changes in the North Atlantic thermohaline circulation (THC) are occurring due to global warming, in 2004 the RAPID programme (working with US scientists) deployed observational arrays across 26.5?N and along the western margin of the basin. These arrays aim to monitor changes in the THC (strictly, in the MOC - meridional overturning circulation) and the propagation of signals in the deep western boundary current (DWBC). The DWBC is part of the lower limb of the THC and the means by which changes further north in the Atlantic propagate south. Analysis of historical in situ observations, to examine changes in the North Atlantic THC over the last 50 years, suggest that significant changes in the MOC may be occurring. The continuous monitoring of the MOC will allow its variability to be measured for the first time and help determine whether it is changing. In conjunction with these observational studies, modelling and analysis of satellite data is being carried out to improve understanding of the processes and mechanisms that cause the THC to vary. This paper describes the recent progress that has been made, presents some initial results from the observational array at 26.5?N, and explains the plans for future studies.

  10. Variations of the mid-latitude ionosphere during strong geomagnetic storms: Observational results

    NASA Astrophysics Data System (ADS)

    Gordiyenko, Galina; Vodyannikov, Victor; Yakovets, Artur

    The ground-based ionosonde data obtained at Alma-Ata station [ϕ = 43.250N, λ = 76.920E, Φ = 33.470N, L = 1.44) are analyzed to study ionospheric responses at fourteen intense (Kp ≥ 8) geomagnetic storms with storm sudden commencement (ssc). The collected data show that ionospheric responses to intensive geomagnetic storms (Dst < -100nT ) are very complex with a great degree of variability; however, negative ionospheric disturbances are a common feature of the responses. The time delay between storm ssc and beginning of the negative ionospheric disturbances shows a tendency to be noticeably larger in winter events than the summer events. Positive ionospheric effects are observed during storm recovery phases or when the Dst almost fully recovered; an enhanced eastward electric field occurred at low and equatorial latitudes after ssc is assumed to be a possible reason for the effects. The occurrence of the unusual for Alma-Ata location night E, F1 layers and auroral type r (retardation) sporadic Es layers is observed during developing or around main phases in Dst index. Employing the International Reference Ionosphere 2001 (IRI-2001), the nighttime E region electron density has been estimated for

  11. Mineral and nitrogen balance study - Results of metabolic observations on Skylab II 28-day orbital mission

    NASA Technical Reports Server (NTRS)

    Whedon, G. D.; Lutwak, L.; Reid, J.; Rambaut, P.; Whittle, M.; Smith, M.; Leach, C.

    1975-01-01

    The prediction that various stresses of flight, particularly weightlessness, would bring about significant derangements in the metabolism of the musculoskeletal system has been based on various balance-study observations of long-term immobilized or inactive bed rest. The three astronauts of Skylab II consumed a planned dietary intake of major metabolic elements in mixed foods and beverages and provided virtually complete collections of excreta for 31 days preflight, 28 days inflight, and 17 days postflight. Analyses showed that, in varying degree among the crewmen, urinary calcium increased gradually during flight in a pattern similar to that observed in bed-rest studies. Fecal calcium excretion did not change significantly, but calcium balance, owing to the urinary calcium rise, became either negative or less positive than in preflight measurement. Increased excretion and negative nitrogen and phosphorus balances inflight indicated appreciable loss of muscle tissue in all three crewmen. Significant losses also occurred inflight in potassium, sodium, and magnesium. Based on the similarity in pattern and degree between these observations of calcium, phosphorus, and nitrogen loss, musculoskeletal integrity would not be threatened in space flights of up to at least 3 months. However, if similar changes occur in the planed Skylab flights for considerably more than 28 days, concern for capable musculoskeletal function should be serious for flights of very many months' duration.

  12. Prospects of an alternative treatment against Trypanosoma cruzi based on abietic acid derivatives show promising results in Balb/c mouse model.

    PubMed

    Olmo, F; Guardia, J J; Marin, C; Messouri, I; Rosales, M J; Urbanová, K; Chayboun, I; Chahboun, R; Alvarez-Manzaneda, E J; Sánchez-Moreno, M

    2015-01-01

    Chagas disease, caused by the protozoa parasite Trypanosoma cruzi, is an example of extended parasitaemia with unmet medical needs. Current treatments based on old-featured benznidazole (Bz) and nifurtimox are expensive and do not fulfil the criteria of effectiveness, and a lack of toxicity devoid to modern drugs. In this work, a group of abietic acid derivatives that are chemically stable and well characterised were introduced as candidates for the treatment of Chagas disease. In vitro and in vivo assays were performed in order to test the effectiveness of these compounds. Finally, those which showed the best activity underwent additional studies in order to elucidate the possible mechanism of action. In vitro results indicated that some compounds have low toxicity (i.e. >150 μM, against Vero cell) combined with high efficacy (i.e. <20 μM) against some forms of T. cruzi. Further in vivo studies on mice models confirmed the expectations of improvements in infected mice. In vivo tests on the acute phase gave parasitaemia inhibition values higher those of Bz, and a remarkable decrease in the reactivation of parasitaemia was found in the chronic phase after immunosuppression of the mice treated with one of the compounds. The morphological alterations found in treated parasites with our derivatives confirmed extensive damage; energetic metabolism disturbances were also registered by (1)H NMR. The demonstrated in vivo activity and low toxicity, together with the use of affordable starting products and the lack of synthetic complexity, put these abietic acid derivatives in a remarkable position toward the development of an anti-Chagasic agent. PMID:25462275

  13. Hubble Tarantula Treasury Project: Unraveling Tarantula's Web. I. Observational Overview and First Results

    NASA Astrophysics Data System (ADS)

    Sabbi, E.; Anderson, J.; Lennon, D. J.; van der Marel, R. P.; Aloisi, A.; Boyer, M. L.; Cignoni, M.; de Marchi, G.; de Mink, S. E.; Evans, C. J.; Gallagher, J. S., III; Gordon, K.; Gouliermis, D. A.; Grebel, E. K.; Koekemoer, A. M.; Larsen, S. S.; Panagia, N.; Ryon, J. E.; Smith, L. J.; Tosi, M.; Zaritsky, D.

    2013-09-01

    The Hubble Tarantula Treasury Project (HTTP) is an ongoing panchromatic imaging survey of stellar populations in the Tarantula Nebula in the Large Magellanic Cloud that reaches into the sub-solar mass regime (<0.5 M ?). HTTP utilizes the capability of the Hubble Space Telescope to operate the Advanced Camera for Surveys and the Wide Field Camera 3 in parallel to study this remarkable region in the near-ultraviolet, optical, and near-infrared spectral regions, including narrow-band H? images. The combination of all these bands provides a unique multi-band view. The resulting maps of the stellar content of the Tarantula Nebula within its main body provide the basis for investigations of star formation in an environment resembling the extreme conditions found in starburst galaxies and in the early universe. Access to detailed properties of individual stars allows us to begin to reconstruct the temporal and spatial evolution of the stellar skeleton of the Tarantula Nebula over space and time on a sub-parsec scale. In this first paper we describe the observing strategy, the photometric techniques, and the upcoming data products from this survey and present preliminary results obtained from the analysis of the initial set of near-infrared observations. Based on observations with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by AURA Inc., under NASA contract NAS 5-26555.

  14. Lung cancer detection with digital chest tomosynthesis: first round results from the SOS observational study

    PubMed Central

    Viti, Andrea; Tavella, Chiara; Priotto, Roberto; Ghirardo, Donatella; Grosso, Maurizio; Terzi, Alberto

    2015-01-01

    Objective Baseline results of the Studio OSservazionale (SOS), observational study, a single-arm observational study of digital chest tomosynthesis for lung cancer detection in an at-risk population demonstrated a detection rate of lung cancer comparable to that of studies that used low dose CT scan (LDCT). We present the results of the first round. Methods Totally 1,703 out of 1,843 (92%) subjects who had a baseline digital chest tomosynthesis underwent a first round reevaluation after 1 year. Results At first round chest digital tomosynthesis, 13 (0.7%) subjects had an indeterminate nodule larger than 5 mm and underwent low-dose CT scan for nodule confirmation. PET/CT study was obtained in 10 (0.5%) subjects and 2 subjects had a low-dose CT follow up. Surgery, either video-assisted thoracoscopic or open surgery for indeterminate pulmonary nodules was performed in 10 (0.2%) subjects. A lung cancer was diagnosed and resected in five patients. The lung cancer detection rate at first round was 0.3% (5/1,703). Conclusions The detection rate of lung cancer at first round for tomosynthesis is comparable to rates reported for CT. In addition, results of first round digital chest tomosynthesis confirm chest tomosynthesis as a possible first-line lung cancer-screening tool. PMID:25992366

  15. Second-Year Results from the Circumarctic Lakes Observation Network (CALON) Project

    NASA Astrophysics Data System (ADS)

    Hinkel, K. M.; Arp, C. D.; Beck, R. A.; Eisner, W. R.; Frey, K. E.; Gaglioti, B.; Grosse, G.; Jones, B. M.; Kim, C.; Lenters, J. D.; Liu, H.; Townsend-Small, A.

    2013-12-01

    Beginning in April 2012, over 55 lakes in northern Alaska were instrumented as the initial phase of CALON, a project designed to document landscape-scale variability in physical and biogeochemical processes of Arctic lakes developed atop permafrost. The current network has nine observation nodes along two latitudinal transects that extend from the Arctic Ocean south 200 km to the foothills of the Brooks Range. At each node, six representative lakes of differing area and depth were instrumented at different intensity levels, and a suite of instruments were deployed to collect field measurements on lake physiochemistry, lake-surface and terrestrial climatology, and lake bed and permafrost temperature. Each April, sensors measuring water temperature and water depth are deployed through the ice and water samples are collected. Sensors are downloaded from lakes and meteorological stations in August, recording a timeline of lake regimes and events from ice decay to the summertime energy and water balance. In general, lake ice thickness increased with latitude. In 2012, ice on deeper (>2 m) lakes was about 1.4 m thick in the Arctic Foothills and 1.7 m thick near the Arctic Ocean coast. Lake ice thickness was about 20 cm thicker in winter 2013 although winter temperatures were several degrees warmer than the previous year; this is likely due to a thinner snow cover in 2013. Lake ice elevations agree with this general trend, showing higher absolute elevation in April 2013 compared to 2012 for most of the surveyed lakes. Regionally, ice-off occurs 2-4 weeks later on lakes near the coast, although there is significant inter-lake variability related to lake depth. Following ice-off, rapid lake warming occurs and water temperature varies synchronously in response to synoptic weather variations and associated changes in net radiation and turbulent heat fluxes. Average mid-summer (July) lake temperatures spanned a relatively wide range in 2012 from 7C to 18C, with higher temperatures in small shallow lakes and more southern latitudes. Most lakes are well-mixed and largely isothermal, with short periods of thermal stratification occurring in deeper lakes during calm, sunny periods. Over the ice-free season, the majority of the available energy from net radiation goes into evaporation, followed by sensible heat flux and warming of bottom sediments. Thermal bands of MODIS and Landsat imagery were fused using a spatio-temporal cokriging method to generate daily surface temperature estimates at Landsat spatial resolution. The close correspondence between satellite-derived and in situ measured near-surface lake temperature suggests that this approach yields viable results. Biogeochemical and inorganic geochemical constituents measured include dissolved greenhouse gas concentrations (CO2, CH4, and N2O), inorganic N, DON and DOC, alkalinity, chlorophyll-a, major ions, and CDOM. The greatest difference in the dissolved CH4:CO2 ratio in summer was longitudinal, with several lakes in western Alaskan Arctic exhibiting CH4 concentrations hundreds of times more supersaturated than air. Stable isotope analyses of CH4 (?13C and ?2H) show that several of these lakes have natural gas methane sources. Methane concentrations under ice (April) were several thousand times higher than in open-water conditions (August). Data collected during this 4-year project are archived at A-CADIS.

  16. In-situ observations of young contrails - overview and selected results from the CONCERT campaign

    NASA Astrophysics Data System (ADS)

    Voigt, C.; Schumann, U.; Jurkat, T.; Schuble, D.; Schlager, H.; Petzold, A.; Gayet, J.-F.; Krmer, M.; Schneider, J.; Borrmann, S.; Schmale, J.; Jessberger, P.; Hamburger, T.; Lichtenstern, M.; Scheibe, M.; Gourbeyre, C.; Meyer, J.; Kbbeler, M.; Frey, W.; Eichler, H.; Butler, T.; Lawrence, M. G.; Holzpfel, F.; Arnold, F.; Wendisch, M.; Dpelheuer, A.; Gottschaldt, K.; Baumann, R.; Zger, M.; Slch, I.; Rautenhaus, M.; Drnbrack, A.

    2010-05-01

    Lineshaped contrails were detected with the research aircraft Falcon during the CONCERT - CONtrail and Cirrus ExpeRimenT - campaign in October/November 2008. Thereby the Falcon was equipped with a set of instruments to measure particle properties such as the particle size distribution, shape, extinction, chemical composition as well as trace gas concentrations of sulfur dioxide (SO2), reactive nitrogen and halogen species (NO, NOy, HNO3, HONO, HCl), ozone (O3) and carbon monoxide (CO). During 12 mission flights over Western Europe numerous contrails and cirrus clouds were probed at altitudes between 8.5 and 11.6 km and temperatures above 213 K. 22 contrails from 11 different aircraft were observed near and below ice saturation. The observed NO mixing ratios, ice crystal and soot number densities are compared to a process based contrail model. Further we investigate in detail the contrail from a CRJ-2 aircraft detected on 19 November 2008 in 10.1 km altitude. The contrail with an age of 1 to 2 min had average ice crystal concentrations of 128 cm-3 in the size range 0.4observation of particles with diameters larger than 100 ?m in the contrail suggests that natural cirrus particles were entrained in the contrail. We further investigate oxidation reactions in the CRJ-2 engine and the contrail. The observed average HONO/NO (HONO/NOy) ratios of 0.037 (0.024) are in the range of previous measurements in the gaseous exhaust. With HONO/NO ratio we can derive a lower limit of the conversion efficiency (?S) of fuel sulfur into H2SO4 of 2.9%. In addition to individual contrails and aircraft plumes, regional stratospheric NO enhancements were detected in the lowest stratosphere. Simulations show that aviation NO emissions could have contributed by more than 40% to the observed NO levels. Besides contrails, also cirrus clouds and a volcanic aerosol layer were measured during the CONCERT campaign. The observations serve to investigate the chemical processing of trace gases on contrails and and help to better quantify the climate impact from contrails.

  17. Hi-C Observations of Penumbral Bright Dots: Comparison with the IRIS Results

    NASA Technical Reports Server (NTRS)

    Alpert, S. E.; Tiwari, S. K.; Moore, R. L.; Savage, S. L.; Winebarger, A. R.

    2014-01-01

    We observed bright dots (BDs) in a sunspot penumbra by using data acquired by the High Resolution Coronal Imager (Hi-C). The sizes of these BDs are on the order of 1 arcsecond (1') and are therefore hard to identify using the Atmospheric Imaging Assembly's (AIA) 0.6' pixel -1 resolution. These BDs become readily apparent with Hi-C's 0.1' pixel -1 resolution. Tian et al. (2014) found penumbral BDs in the transition region (TR) by using the Interface Region Imaging Spectrograph (IRIS). However, only a few of their dots could be associated with any enhanced brightness in AIA channels. In this work, we examine the characteristics of the penumbral BDs observed by Hi-C in a sunspot penumbra, including their sizes, lifetimes, speeds, and intensity. We also attempt to relate these BDs to the IRIS BDs. There are fewer Hi-C BDs in the penumbra than seen by IRIS, though different sunspots were studied and Hi-C had a short observation time. We use 193 A Hi-C data from July 11, 2012 which observed from 18:52:00 UT{18:56:00 UT and supplement it with data from AIA's 193 A passband to see the complete lifetime of the dots that were born before and/or lasted longer than Hi-C's 5-minute observation period. We use additional AIA passbands and compare the light curves of the BDs at different temperatures to test whether the Hi-C BDs are TR BDs. We find that most Hi-C BDs show clear movement, and of those that do, they move in a radial direction, toward or away from the sunspot umbra, sometimes doing both. BDs interact with other BDs, combining to fade away or brighten. The BDs that do not interact with other BDs tend to move less and last longer. We examine the properties of the Hi-C BDs and compare them with the IRIS BDs. Our BDs are similar to the exceptional values of the IRIS BDs: they move slower on average and their sizes and lifetimes are on the higher end of the distributions of IRIS BDs. We infer that our penumbral BDs are some of the larger BDs observed by IRIS.

  18. More screen operation than calling: the results of observing cyclists' behaviour while using mobile phones.

    PubMed

    de Waard, Dick; Westerhuis, Frank; Lewis-Evans, Ben

    2015-03-01

    Operating a mobile telephone while riding a bicycle is fairly common practice in the Netherlands, yet it is unknown if this use is stable or increasing. As such, whether the prevalence of mobile phone use while cycling has changed over the past five years was studied via on-road observation. In addition the impact of mobile phone use on lateral position, i.e. distance from the front wheel to the curb, was also examined to see if it compared to the results seen in previous experimental studies. Bicyclists were observed at six different locations and their behaviour was scored. It was found that compared to five years ago the use of mobile phones while cycling has changed, not in frequency, but in how cyclists were operating their phones. As found in 2008, three percent of the bicyclists were observed to be operating a phone, but a shift from calling (0.7% of cyclists observed) to operating (typing, texting, 2.3% of cyclists) was found. In 2008 nearly the complete opposite usage was observed: 2.2% of the cyclists were calling and 0.6% was texting. Another finding was that effects on lateral position were similar to those seen in experimental studies in that cyclists using a phone maintained a cycling position which was further away from the curb. It was also found that when at an intersection, cyclist's operating their phone made less head movements to the right than cyclists who were just cycling. This shift from calling to screen operation, when combined with the finding related to reduced head movements at intersections, is worrying and potentially dangerous. PMID:25590920

  19. Greenhouse gases observation from space -initial operation and calibration results of TANSO on GOSAT- (Invited)

    NASA Astrophysics Data System (ADS)

    Kuze, A.; Shiomi, K.; Suto, H.; Nakajima, M.

    2009-12-01

    The Greenhouse gases Observing SATellite (GOSAT) observes carbon dioxide (CO2) and methane (CH4) globally from space. It is a joint project of Japan Aerospace Exploration Agency (JAXA), Ministry of the Environment (MOE) and National Institute for Environmental Studies (NIES). GOSAT was launched on January 23, 2009 from Tanegashima Space Center and placed in a 666 km sun-synchronous orbit of 12:48 local time, with an inclination angle of 98 deg. There are two instruments: the Thermal And Near infrared Sensor for carbon Observation Fourier-Transform Spectrometer (TANSO-FTS) detects gas absorption spectra of Short Wave InfraRed (SWIR) reflected on the earth's surface as well as of Thermal InfraRed (TIR) radiated from the ground and the atmosphere. TANSO-FTS is capable of detecting wide spectral coverage; three narrow bands (0.76, 1.6, and 2?m) and a wide band (5.5-14.3 ?m) with 0.27 cm-1 spectral resolution. The TANSO Cloud and Aerosol Imager (TANSO-CAI) is a radiometer of ultraviolet (UV), visible, and SWIR to detect cloud and aerosol interference. TANSO-FTS and CAI acquire global data every three days. For the first six months after the launch, on-orbit function, performance, calibration, and validation have been checked-out. The presentation includes instrument design, pre-launch test results, observation plan, onboard calibration schemes, and the initial on-orbit results of radiometric, geometric and spectroscopic performances. The data processing on the ground is also presented.

  20. Multiple layer PMSE structures: statistical results from six years of PMSE observations and possible physical explanations of their observed properties

    NASA Astrophysics Data System (ADS)

    Hoffmann, Peter; Rapp, Markus; Latteck, Ralph; Serafimovich, Andrei; Singer, Werner

    2003-08-01

    Polar Mesosphere Summer Echoes (PMSE) have been studied at Andenes (69N, 16E), Norway, using VHF radar observations from 1994-1997 and since 1999. One remarkable feature of all PMSE is the fact that the radar echoes often occur in the form of two or more distinct layers that can persist for periods of up to several hours. Until now, the layering-mechanism leading to these multiple structures is not well understood. Here we are studying the occurrence and the mean altitude distribution of these multiple layer events. To discuss the processes which are potentially responsible for the creation of these multiple structures, we apply a microphysical model of the generation and growth of mesospheric ice particles under the influence of a temperature and wind variation caused by a long period gravity wave together with a charging model. Finally, this theoretical approach is tested in a first case study to investigate gravity wave characteristics derived from VHF radar wind measurements during the PMSE observations.

  1. Mantle Anisotropy Beneath the Alaska Range Inferred From S-wave Splitting Observations: Results From BEAAR

    NASA Astrophysics Data System (ADS)

    Christensen, D. H.; Abers, G. A.; McKnight, T. L.

    2003-12-01

    The tectonics of southern and central Alaska are dominated by the subduction of the Pacific plate beneath the North American plate. The Broadband seismic Experiment Across the Alaska Range (BEAAR) was a 2.5-year PASSCAL deployment utilizing 36 closely spaced (10-15 km) broadband sensors. These instruments were deployed across the Alaska Range and above the subducting Pacific plate in roughly north-south and east-west lines. Much of the study region is underlain by a mantle wedge, which gradually pinches out at the southernmost stations. The depth of the subducting slab increases to the northwest with the deepest earthquakes occurring at 150 km, just north of the Alaska Range. Teleseismic SKS and S phases, in addition to S waves from local earthquakes in the subducting plate, were used to study the anisotropic behavior of the upper mantle in central Alaska. Two distinct regions of anisotropy are observed, reflecting both flow in the direction of plate convergence and flow parallel to the strike of the subducting plate. The transition between these two zones appears to be very sharp occurring near the 70-75 km contour of the subducting plate. Waves arriving through material southeast of this line (through the shallow corner of the mantle wedge) show fast directions that are parallel to the plate convergence direction. North of the 70-75 km slab contour the fast directions abruptly change orientation to roughly parallel the strike to the subducting plate. This direction is also parallel to the trend of several major tectonic features in the area, including the Alaska Range, and the right-lateral strike slip Denali and Tintina faults. Stations that are located above the 70-75 km contour of the subducting Pacific plate show characteristics of both regions, depending on the back azimuth of the arrivals. These observations set strong constraints on the location of the transition zone between the two regions. While teleseismic observations may represent anisotropy (or flow) in the mantle wedge, in the subducting Pacific plate, or beneath the subducting plate, observations from local slab events indicate that a significant portion of the signal comes from the mantle wedge and that the sharp change in direction is a feature of the mantle wedge.

  2. Revisiting Spitzer Transit Observations with Independent Component Analysis: New Results for the GJ 436 System

    NASA Astrophysics Data System (ADS)

    Morello, G.; Waldmann, I. P.; Tinetti, G.; Howarth, I. D.; Micela, G.; Allard, F.

    2015-04-01

    We analyzed four Spitzer/IRAC observations at 3.6 and 4.5 ?m of the primary transit of the exoplanet GJ 436b, by using blind source separation techniques. These observations are important for investigating the atmospheric composition of the planet GJ 436b. Previous analyses claimed strong inter-epoch variations of the transit parameters due to stellar variability, casting doubts on the possibility of conclusively extracting an atmospheric signal. Those analyses also reported discrepant results, hence the necessity of this reanalysis. The method we used has been proposed in Morello et al. to analyze 3.6 ?m transit light curves of the hot Jupiter HD 189733b. It performes an Independent Component Analysis on a set of pixel light curves, i.e., time series read by individual pixels, from the same photometric observation. Our method only assumes the independence of instrumental and astrophysical signals, and therefore guarantees a higher degree of objectivity compared to parametric detrending techniques published in the literature. The data sets we analyzed in this paper represent a more challenging test than the previous ones. Contrary to previous results reported in the literature, our results (1) do not support any detectable inter-epoch variations of orbital and stellar parameters, (2) are photometrically stable at the level 10-4 in the IR, and (3) the transit depth measurements at the two wavelengths are consistent within 1?. We also (4) detect a possible transit duration variation of 80 s (2? significance level) that has not been pointed out in the literature, and (5) confirm no transit timing variations ?30 s.

  3. Worldwide variations in atmospheric transmission. I - Baseline results from Smithsonian observations.

    NASA Technical Reports Server (NTRS)

    Roosen, R. G.; Klemcke, C. H.; Angione, R. J.

    1973-01-01

    The spectrobolometer used in the studies is discussed, giving attention to instrument design, the method of recording, and the spectral resolution. The atmospheric transmission for each wavelength was determined by making observations over a range of air masses. The precipitable water vapor values were found from the spectrobolograms by measurement of the depths of water vapor bands at 0.935, 1.13, and 1.47 microns. The results of the studies are discussed together with seasonal variations, long term trends, and the nature of the aerosols.

  4. MHD Model Results of Solar Wind Plasma Interaction with Mars and Comparison with MAVEN Observations

    NASA Technical Reports Server (NTRS)

    Ma, Y. J.; Russell, C. T.; Nagy, A. F.; Toth, G.; Halekas, J. S.; Connerney, J. E. P.; Espley, J. R.; Mahaffy, P. R.

    2015-01-01

    The crustal remnant field on Mars rotates constantly with the planet, varying the magnetic field configuration interacting with the solar wind. It has been found that ion loss rates slowly vary with the subsolar longitude, anticorrelating with the intensity of the dayside crustal field source, with some time delay, using a time-dependent multispecies MHD model. In this study, we investigate in detail how plasma properties are influenced locally by the crustal field and its rotation. Model results will be compared in detail with plasma observations from MAVEN.

  5. Cassini RADAR Observations at Titan : Results at the End of the Nominal Mission

    NASA Astrophysics Data System (ADS)

    Lorenz, Ralph

    This talk will review some recent results of the Cassini RADAR investigations at Titan. In particular, the first half of 2008 includes three low-latitude flybys with SAR observations of Xanadu, the Huygens Landing site, and in particular three areas that may be associated with cryovolcanic features - Tortola Facula, Hotei Arcus, and Tui Regio. In addition to providing SAR coverage (which will include further mapping of dunes in the Shangri-La dark areas as well as the features above), these new flybys will permit refinement of the apparently dynamic Titan rotational state, as well as expanding our topographic knowledge.

  6. Results of Observational Studies: Analysis of Findings from the Nurses’ Health Study

    PubMed Central

    Tai, Vicky; Grey, Andrew; Bolland, Mark J.

    2014-01-01

    Background The role of observational studies in informing clinical practice is debated, and high profile examples of discrepancies between the results of observational studies and randomised controlled trials (RCTs) have intensified that debate. We systematically reviewed findings from the Nurses’ Health Study (NHS), one of the longest and largest observational studies, to assess the number and strength of the associations reported and to determine if they have been confirmed in RCTs. Methods We reviewed NHS publication abstracts from 1978–2012, extracted information on associations tested, and graded the strength of the reported effect sizes. We searched PubMed for RCTs or systematic reviews for 3 health outcomes commonly reported in NHS publications: breast cancer, ischaemic heart disease (IHD) and osteoporosis. NHS results were compared with RCT results and deemed concordant when the difference in effect sizes between studies was ≤0.15. Findings 2007 associations between health outcomes and independent variables were reported in 1053 abstracts. 58.0% (1165/2007) were statistically significant, and 22.2% (445/2007) were neutral (no association). Among the statistically significant results that reported a numeric odds ratio (OR) or relative risk (RR), 70.5% (706/1002) reported a weak association (OR/RR 0.5–2.0), 24.5% (246/1002) a moderate association (OR/RR 0.25–0.5 or 2.0–4.0) and 5.0% (50/1002) a strong association (OR/RR ≤0.25 or ≥4.0). 19 associations reported in NHS publications for breast cancer, IHD and osteoporosis have been tested in RCTs, and the concordance between NHS and RCT results was low (≤25%). Conclusions NHS publications contain a large number of analyses, the majority of which reported statistically significant but weak associations. Few of these associations have been tested in RCTs, and where they have, the agreement between NHS results and RCTs is poor. PMID:25330007

  7. Preliminary Results on Polarization Observables for Double-Pion Photoproduction from FROST

    NASA Astrophysics Data System (ADS)

    Roy, P.; Park, S.; Crede, V.; CLAS Collaboration

    2013-10-01

    Hadron spectroscopy is essential to understand nucleon structure in the low energy regime. Many low mass resonances have been observed via ?N scattering but only a few resonances above 1.7 GeV have been seen so far. It is speculated that photoproduction could be the key to detect the missing resonances, many of which probably decay into multi-particle final states. Double-pion photoproduction with p?+?- final state becomes the biggest contributor to the total cross section for center-of-mass energies above 1.7 GeV, making it an indispensable channel to explore. It is imperative to measure polarization observables to isolate the resonant and non-resonant contributions to this reaction for the extraction of N* parameters. Here we report on the preliminary results obtained for polarization observables I?, Pz, Pz&sun; from the study of ?+?- photoproduction using circularly polarized photons (E? up to 2.3 GeV) incident on a longitudinally polarized butanol target and discuss the ongoing analysis to extract Pxs , c , Pys , c using linearly polarized photons (coherent edge up to 2.1 GeV) and a transversely polarized target. The experiments were conducted at Jefferson Lab using the CLAS spectrometer. This work is supported by DOE # DE-FG02-92ER40735.

  8. First Results of Coordinated Observations from IRIS and New Solar Telescope

    NASA Astrophysics Data System (ADS)

    Kosovichev, A. G.; Cao, W.; Goode, P. R.; Gorceix, N.; Kleint, L.; Plymate, C.; Varsik, J. R.; Shumko, S.; Yurchyshyn, V.

    2013-12-01

    Most of the chromospheric structuring and dynamics is controlled by the underlying photospheric processes, associated with turbulent magnetoconvection, ubiquitous magnetic flux emergence, small-scale eruptions and acoustic events. The 1.6 m New Solar Telescope (NST) of Big Bear Solar Observatory offers a substantial improvement in ground-based high-resolution capabilities, and provides important support for the IRIS mission. The primary goal of the coordinated IRIS-NST observations is to obtain complementary data for investigations of photosphere-chromosphere links and drivers of the chromospheric dynamics. The coordinated NST observations are performed using the second-generation adaptive optics system AO-308, and three instruments: Broadband Filter Imagers (G-band and TiO), Visible Imaging Spectrometer (H-alpha), and Near InfraRed Imaging Spectropolarimeter (NIRIS). NIRIS provides high-cadence data in Fe I 1565 nm doublet which is the most Zeeman sensitive probe of magnetic fields in the deep photosphere, and in the He I 1083 nm multiplet for diagnostics of the upper chromosphere. We present initial results of the coordinated observations, and discuss properties of small-scale ejections in fibril magnetic structures, obtained from analysis of IRIS and NST data.

  9. Results of IPS Observations in the Period Near Solar Activity Minimum

    NASA Astrophysics Data System (ADS)

    Chashei, I. V.; Shishov, V. I.; Tyul'bashev, S. A.; Subaev, I. A.; Oreshko, V. V.

    2013-07-01

    IPS observations with the Big Scanning Array of Lebedev Physical Institute (BSA LPI) radio telescope at the frequency 111 MHz have been monitored since 2006. All the sources, about several hundred daily, with a scintillating flux greater than 0.2 Jy are recorded for 24 hours in the 16 beams of the radio telescope covering a sky strip of 8∘ declination width. We present some results of IPS observations for the recent period of low solar activity considering a statistical ensemble of scintillating radio sources. The dependences of the averaged over ensemble scintillation index on heliocentric distance are considerably weaker than the dependence expected for a spherically symmetric geometry. The difference is especially pronounced in the year 2008 during the very deep solar activity minimum period. These features are explained by the influence of the heliospheric current sheet that is seen as a strong concentration of turbulent solar wind plasma aligned with the solar equatorial plane. A local maximum of the scintillation index is found in the anti-solar direction. Future prospects of IPS observations using BSA LPI are briefly discussed.

  10. Gravity Changes and Internal Processes: Some Results Obtained from Observations at Three Volcanoes

    NASA Astrophysics Data System (ADS)

    Jentzsch, Gerhard; Weise, Adelheid; Rey, Carlos; Gerstenecker, Carl

    Temporal gravity changes provide information about mass and/or density variations within and below the volcano edifice. Three active volcanoes have been under investigation; each of them related to a plate boundary: Mayon/Luzon/Philippines, Merapi/Java/Indonesia, and Galeras/Colombia. The observed gravity changes are smaller than previously expected but significant. For the three volcanoes under investigation, and within the observation period, mainly the increase of gravity is observed, ranging from 1,000 nm-2 to 1,600 nms-2. Unexpectedly, the gravity increase is confined to a rather small area with radii of 5 to 8 km around the summit. At Mayon and Merapi the parallel GPS measurements yield no significant elevation changes. This is crucial for the interpretation, as the internal pressure variations do not lead to significant deformation at the surface. Thus the classical Mogi-model for a shallow extending magma reservoir cannot apply. To confine the possible models, the attraction due to changes of groundwater level or soil moisture is estimated along the slope of Merapi exemplarily by 2-D modelling. Mass redistribution or density changes were evaluated within the vent as well as deeper fluid processes to explain the gravity variations; the results are compared to the model incorporating the additional effect of elastic deformation.

  11. The Results of the Five-year Observation of GOSAT and toward the GOSAT-2 Mission

    NASA Astrophysics Data System (ADS)

    Nakajima, Masakatsu; Shiomi, Kei; Kuze, Akihiko; Suto, Hiroshi

    Greenhouse gases Observing SATellite (GOSAT) was launched on January 23, 2009, to monitor the global column concentration of carbon dioxide (CO2) and methane (CH4) from space. And the data processing algorithms have been improved several times based on the calibration and validation activities which have been performed through the on-orbit operation and these activities have resulted in the improvements of the accuracy of the net flux of the carbon dioxide as well as the one of the concentrations. That is to say, the measurement targets of carbon dioxide and methane concentration were accomplished as well as the target of the reduction of the estimation error of carbon dioxide flux. In addition, the methane flux was calculated using GOSAT observation data, and this flux was placed as the standard products and will be released to public along with the carbon dioxide flux. The latest data has precision of about 2ppm and bias of lower than 1ppm, and now the verification of the new level 1B processing algorithm has been performed and will be released in near future. This new algorithm will be able to make it possible to derive the vertically-separated concentraion data from the thermal infrared channel. These results such as the monthly concentration maps of five years and fluxes of a few years will be introduced in the presentation On the other hand, the accuracy of the GOSAT measurements is not enough for the operational uses such as the political purpose. And it has been required to improve the observation performance such as signal to noise ratio, the number of the useful data and the density of the observation points. Therefore the GOSAT-2 project started to improve the measurement accuracy of carbon dioxide and methane, and the reduction of the estimation error of the flux. In addition to these improvements, the new observation target, carbon monoxide, was added to study the anthropogenic emission of the greenhouse gases. In the presentation, the mission of the GOSAT-2 and the hardware system will be introduced.

  12. Direct Observation of Differences of Carotenoid Polyene Chain cis/trans Isomers Resulting from Structural Topology

    PubMed Central

    2015-01-01

    In the present paper, trapped ion mobility spectrometry (TIMS) and theoretical calculations have been used to study carotenoid geometrical motifs generated by photoisomerization from the all-trans geometry. Multiple geometric isomers of the carotenoids lutein and zeaxanthin were separated using TIMS (R > 110) for [M]+, [M + H]+, and [M – 18]+ molecular species. Comparison of observed cross sections with those obtained from molecular dynamics calculations showed that the number of cis double bonds and s-cis single bonds in the polyene chain determine the topology space of the carotenoid. The intensities of IMS signals are correlated with the relative stability of these geometric isomers.1,2 The most stable isomer is the all-trans geometry regardless of the ionization state ([M – 18]+, [M]+, and [M + H]+), and structural stability decreases with the increasing number of cis and/or s-cis bonds in the polyene chain. PMID:24428664

  13. First results of mapping sporadic E with a passive observing network

    NASA Astrophysics Data System (ADS)

    Rice, D. D.; Sojka, J. J.; Eccles, J. V.; Raitt, J. W.; Brady, J. J.; Hunsucker, R. D.

    2011-12-01

    Sporadic E (Es) can have dramatic effects on communications in the HF and low VHF range, producing over-the-horizon propagation for signals normally restricted to line-of-sight, and sometimes blocking F region propagation of signals in the lower HF range. Measuring the E region winds believed to produce Es is difficult, and no practical means of predicting Es occurrence currently exists other than statistical models. We describe a low-cost observing network based on software-controlled receivers that continuously watches for Es in near-real time using oblique HF propagation from existing transmitters. Results from an 11-day pilot campaign in July 2008 demonstrated that even a limited number of receivers in the network can readily determine the presence and extent of Es patches. These observations indicate that Es often develops quickly over regions of several hundred kilometers rather than gradually drifting across an area. These widespread Es blooms have been observed near winter solstice and occasionally at other times of the year; their lifetime depends on the season but can be several hours during the summer. The current network allows the extent of Es in portions of North America to be evaluated: the geographical distribution of Es and bounds on the density of the layer are inferred from its effects on the ionospheric maximum usable frequency (MUF). This study demonstrates quantitatively that Es mapping can provide information about Es layer geographical growth and decay. The observed sudden widespread Es blooms are space weather events that can have significant impact on HF/lower VHF communications and propagation model predictions.

  14. Results of observations of the tritium concentration in water fractions in the disposition regions of tritium laboratories

    SciTech Connect

    Koval, G.N.; Kuzmina, A.I.; Kolomiets, N.F.; Svarichevskaya, E.V.; Rogosin, V.N.; Svyatun, O.V.

    1995-10-01

    In this paper results of the long term of control of tritium concentration in the water fractions in the region close to the tritium laboratories of INR NAS of Ukraine are presented. The regular observations for the tritium concentration in the water fractions (thawed water of the snow cover, birch juice and sewer water) in the influence region of tritium laboratories shows small amount of tritium concentration in all kinds of investigated water fractions in comparison with the tritium concentration in the reper points. The proper connection of the levels of tritium concentration of the water samples with the quantity of the technology production is observed. In common, the tritium pollution on the territory of INR shows the tendency for a considerable decrease of the environmental pollution levels from year to year. It can be explained by the perfection of the production technology of tritium structures and targets as well as the rising of the qualification of the personnel. 3 refs., 4 figs.

  15. The Evolution of Stellar Coronae: Initial Results from a ROSAT PSPC Observation of IC 2391

    NASA Technical Reports Server (NTRS)

    Patten, Brian M.; Simon, Theodore

    1993-01-01

    A 23 ks ROSAT PSPC image of the young star cluster, IC 2391, reveals 76 soft x-ray sources with L(sub x)(0.2-2.0 keV) greater than or equal to 2 x 10(exp 28) ergs/s in the direction of the cluster center. Nineteen of these sources are associated with known cluster members. We find that x-ray emission from the IC 2391 B stars deviates widely from the L(sub x)/L(sub bol) = 10(exp -7) relation based on Einstein observations of O and early B stars. Instead, we observe a wide range in L(sub x) with an order of magnitude spread at any given mass and no apparent dependence on spectral type. A comparison of the spread of L(sub x) as a function of B-V for low-mass stars between IC 2391 and the much older Hyades cluster shows that despite the factor of approx. 10 difference in their ages, these two clusters exhibit very similar dispersions in levels of stellar activity. We conclude that the low-mass stars in IC 2391 have arrived on the ZAMS with a wide range of coronal activity levels, from very strong to very weak, and that existing empirical activity-age scaling laws therefore cannot be valid.

  16. The reliability of observational approaches for detecting interspecific parasite interactions: comparison with experimental results.

    PubMed

    Fenton, Andy; Knowles, Sarah C L; Petchey, Owen L; Pedersen, Amy B

    2014-06-01

    Interactions among coinfecting parasites have the potential to alter host susceptibility to infection, the progression of disease and the efficacy of disease control measures. It is therefore essential to be able to accurately infer the occurrence and direction of such interactions from parasitological data. Due to logistical constraints, perturbation experiments are rarely undertaken to directly detect interactions, therefore a variety of approaches are commonly used to infer them from patterns of parasite association in observational data. However, the reliability of these various approaches is not known. We assess the ability of a range of standard analytical approaches to detect known interactions between infections of nematodes and intestinal coccidia (Eimeria) in natural small-mammal populations, as revealed by experimental perturbations. We show that correlation-based approaches are highly unreliable, often predicting strong and highly significant associations between nematodes and Eimeria in the opposite direction to the underlying interaction. The most reliable methods involved longitudinal analyses, in which the nematode infection status of individuals at one month is related to the infection status by Eimeria the next month. Even then, however, we suggest these approaches are only viable for certain types of infections and datasets. Overall we suggest that, in the absence of experimental approaches, careful consideration be given to the choice of statistical approach when attempting to infer interspecific interactions from observational data. PMID:24704058

  17. The Hubble Space Telescope quasar absorption line key project. III - First observational results on Milky Way gas

    NASA Technical Reports Server (NTRS)

    Savage, Blair D.; Lu, Limin; Bahcall, John N.; Bergeron, Jacqueline; Boksenberg, Alec; Hartig, George F.; Jannuzi, Buell T.; Kirhakos, Sofia; Lockman, Felix J.; Sargent, W. L. W.

    1993-01-01

    Absorption lines found near zero redshift due to Milky Way disk and halo gas in the spectra of 15 quasars observed with the Faint Object Spectrograph (FOS) of the HST at a resolution of about 230 km/s are reported. Results show that Milky Way absorption lines comprise about 44 percent of all absorption lines seen in the first group of Key Project FOS spectra. Milky Way lines were observed for 3C 273 and H1821 + 643. Limits to the Mg-to-H abundance ratio obtained for very high velocity Mg II absorption detections imply gas-phase Mg abundances for the very high velocity gas ranging from more than 0.059 to more than 0.32 times the solar abundance. In all cases where high-velocity H I emission is seen, corresponding high-velocity metal-line absorption is observed.

  18. Astrometric results of observations at Russian observatories of mutual occultations and eclipses of Jupiter's Galilean satellites in 2009

    NASA Astrophysics Data System (ADS)

    Emelyanov, N. V.; Andreev, M. V.; Berezhnoi, A. A.; Bekhteva, A. S.; Vashkovyak, S. N.; Velikodskii, Yu. I.; Vereshchagina, I. A.; Gorshanov, D. L.; Devyatkin, A. V.; Izmailov, I. S.; Ivanov, A. V.; Irsmambetova, T. R.; Kozlov, V. A.; Karashevich, S. V.; Kurenya, A. N.; Naiden, Ya. V.; Naumov, K. N.; Parakhin, N. A.; Raskhozhev, V. N.; Selyaev, S. A.; Sergeev, A. V.; Sokov, E. N.; Khovrichev, M. Yu.; Khrutskaya, E. V.; Chernikov, M. M.

    2011-06-01

    In 2009, in five Russian observatories photometric observations of Jupiter's Galilean satellites during their mutual occultations and eclipses were carried out. Based on these observations, an original method was used to ascertain astrometric results such as the difference between the coordinates of pairs of satellites. Fifty-three phenomena were successfully observed. A total of 94 light curves of satellites were measured. The error in the coordinates of satellites due to random errors in photometry, calculated on all data obtained, was 0.041? in right ascension and 0.046? in declination. The discrepancies between the theory and observations in these coordinates was found to be 0.060? and 0.057?, respectively. The results were uploaded to the common database for all observations of natural satellites of planets at the Natural Satellites Data Center (NSDC), which is available online at http://www.sai.msu.ru/neb/nss/index.htm . For the first time in the practice of photometric observations of satellites in epochs of mutual occultations and eclipses a new method of observation was tested, which eliminates from astrometric results the major systematic errors caused by an inaccurate account of the background level. The tests were conducted in the Terskol Observatory and the observatory of the Crimean laboratory of the Sternberg State Astronomical Institute of the Moscow State University. The application of the new method showed that the elimination of the background level at these observatories was carried out correctly.

  19. Results of NASA's First Autonomous Formation Flying Experiment: Earth Observing-1 (EO-1)

    NASA Technical Reports Server (NTRS)

    Folta, David C.; Hawkins, Albin; Bauer, Frank H. (Technical Monitor)

    2001-01-01

    NASA's first autonomous formation flying mission completed its primary goal of demonstrating an advanced technology called enhanced formation flying. To enable this technology, the Guidance, Navigation, and Control center at the Goddard Space Flight Center (GSFC) implemented a universal 3-axis formation flying algorithm in an autonomous executive flight code onboard the New Millennium Program's (NMP) Earth Observing-1 (EO-1) spacecraft. This paper describes the mathematical background of the autonomous formation flying algorithm and the onboard flight design and presents the validation results of this unique system. Results from functionality assessment through fully autonomous maneuver control are presented as comparisons between the onboard EO-1 operational autonomous control system called AutoCon(tm), its ground-based predecessor, and a standalone algorithm.

  20. Results Of NASA's First Autonomous Formation Flying Experiment: Earth Observing-1 (EO-1)

    NASA Technical Reports Server (NTRS)

    Folta, David; Hawkins, Albin

    2002-01-01

    NASA's first autonomous formation flying mission completed its primary goal of demonstrating an advanced technology called Enhanced Formation Flying. To enable this technology, a team at the Goddard Space Flight Center implemented a universal 3-axis formation flying algorithm in an autonomous executive flight code onboard the New Millennium Program's (NMP) Earth Observing-1 (EO-1) spacecraft. This paper describes the mathematical background of the autonomous formation flying algorithm, the onboard flight design and the validation results of this unique system. Results from fully autonomous maneuver control are presented as comparisons between the onboard EO-1 operational autonomous control system called AutoCon(trademark), its ground-based predecessor used in operations, and the original standalone algorithm. Maneuvers discussed encompass reactionary, routine formation maintenance, and inclination control. Orbital data is also examined to verify that all formation flying requirements were met.

  1. Surface electromagnetic impedance and geomagnetic activity: results of long term observation

    NASA Astrophysics Data System (ADS)

    Lemperger, Istvn; Menvielle, Menvielle; Wesztergom, Viktor; Bencze, Pl; Szendr?i, Judit; Novk, Attila; Kis, rpd; Szalai, Sndor

    2014-05-01

    The magnetotelluric (MT) method is one of the most useful geophysical tool to discover even the deep subsurface structures. The target function of the MT data processing is the surface electromagnetic (EM) impedance. In case of practical MT exploration the surface EM impedance is computed based on a simplification related to the nature of the ionospheric source of the surface EM signals. Assuming that the ionospheric current systems result in homogeneous surface electromagnetic variations, the uncertainty of the computed surface electromagnetic impedance tensor depends only the duration of the EM observation. However the surface EM field can only be approached by plane waves in certain time periods and besides given uncertainty. The EM impedance may be sensitive to magnetospheric and -indirectly- interplanetary circumstances and solar activity. Four years continuous observation of telluric and surface geomagnetic components allowed to perform a representative survey to discover if geomagnetic activity has any effect on observed EM impedance tensor. Geomagnetic indices (Dst, ULF-index, ASY-H, SYM-H) have been used to classify dates according to geomagnetic activity. Processing to estimate the mean surface EM impedance tensor has been performed in each dataset, each class separately. The sensitivity and the characteristics of the answer of the EM impedance tensor to the geomagnetic disturbances seems to be definite. This presentation aims to briefly summarize the preliminary results of our study based on the unique dataset of the Szchenyi Istvn Geophysical Obsevatory (Intermagnet code:NCK). In addition, pointing out the limitations of the routine way of practical MT data processing and interpretation is an important duty of this study. This study was supported by the TAMOP-4.2.2.C-11/1/KONV-2012-0015 (Earth-system) project sponsored by the EU and European Social Foundation.

  2. Recent Observational Results of Seafloor Crustal Deformation Along the Suruga-Nankai Trough, Japan

    NASA Astrophysics Data System (ADS)

    Tadokoro, K.; Sugimoto, S.; Watanabe, T.; Muto, D.; Kimoto, A.; Okuda, T.; Ikuta, R.; Sayanagi, K.; Kuno, M.

    2008-12-01

    The Suruga-Nankai Trough is one of the active plate boundaries in the world. The Philippine Sea plate is subducting beneath the Amurian (Eurasian) plate along the tough, and major subduction earthquakes, Nankai and Tonankai earthquakes, have repeatedly occurred with intervals of about 100-150 years. The 1944 Tonankai and 1946 Nankai earthquakes are the most recent significant earthquakes along the trough. Therefore, the 50-years probabilities of the next major earthquakes are estimated at 80-90% by Headquarters for Earthquake Research Promotion, Japanese Government. It is, therefore, necessary to start monitoring crustal deformation above the source regions of the major earthquakes where in the ocean area. We developed a new system composed of the precise acoustic ranging and kinematic GPS positioning techniques for monitoring of seafloor crustal deformation [Tadokoro et al., 2006, GRL; Ikuta et al., 2008, JGR]. We had installed seven seafloor benchmarks for acoustic ranging at the Suruga-Nankai Trough region between 2002 and 2004. The water depths at the benchmarks are about 800 to 2000 m. We installed a new seafloor benchmark at the eastern margin of the Kumano Basin on June 23, 2008. Three seafloor benchmarks had been aligned perpendicular to the trough axis. In contrast, the new benchmark was installed eastward relative to the pre-installed benchmarks, and we can monitor lateral variations in crustal deformation at the region. We started the repeated measurements at four benchmarkes (two at the Kumano Basin named KMN and KMS, and the other two at the Suruga Bay named SNW and SNE) in 2005. The number of times we have measured are seven, eleven, three and nine times at KMN, KMS, SNW and SNE, respectively. Recent results of the repeated measurements show the following horizontal velocities with relative to the Amurian Plate: 6.4 cm/yr, N86W at KMN; 5.3 cm/yr, N71W at KMS; 3.3 cm/yr, N57W at SNE. The errors of the horizontal velocities are 1-3 cm/yr. Unfortunately, we have not detected any velocity at SNW benchmark because of the insufficient number of measurements as of August 2008. The orientations of the horizontal velocities is almost consistent to those derived from the on-land dense GPS observation network, GEONET of Geographical Survey Institute, Japan. Temporal and spatial variations in sound speed are major source of error in the benchmark positioning. Now we are developing other system with plural sea-surface transducers for positioning sea-bottom benchmarkes with acoustic tomography method to reduce the error caused by the sound speed variations. Acknowledgments: We are grateful to the captain and crews of R/Vs "Hokuto," Tokai University and "Asama," Mie Prefecture Fisheries Research Institute, Japan. This study has been promoted by "Research Revolution 2002" and "DONET project" of Ministry of Education, Culture, Sports, Science and Technology, Japan.

  3. Hubble Tarantula Treasury Project: Unraveling Tarantula's Web. I. Observational Overview and First Results

    NASA Technical Reports Server (NTRS)

    Sabbi, E.; Anderson, J.; Lennon, D. J.; van der Marel, R. P.; Aloisi, A.; Boyer, Martha L.; Cignoni, M.; De Marchi, G.; De Mink, S. E.; Evans, C. J.; Gallagher, J. S., III; Gordon, K.; Gouliermis, D. A.; Grebel, E. K.; Koekemoer, A. M.; Larsen, S. S.; Panagia, N.; Ryon, J. E.; Smith, L. J.; Tosi, M.; Zaritsky, D.

    2013-01-01

    The Hubble Tarantula Treasury Project (HTTP) is an ongoing panchromatic imaging survey of stellar populations in the Tarantula Nebula in the Large Magellanic Cloud that reaches into the sub-solar mass regime (<0.5 Stellar Mass). HTTP utilizes the capability of the Hubble Space Telescope to operate the Advanced Camera for Surveys and the Wide Field Camera 3 in parallel to study this remarkable region in the near-ultraviolet, optical, and near-infrared spectral regions, including narrow-band H(alpha) images. The combination of all these bands provides a unique multi-band view. The resulting maps of the stellar content of the Tarantula Nebula within its main body provide the basis for investigations of star formation in an environment resembling the extreme conditions found in starburst galaxies and in the early universe. Access to detailed properties of individual stars allows us to begin to reconstruct the temporal and spatial evolution of the stellar skeleton of the Tarantula Nebula over space and time on a sub-parsec scale. In this first paper we describe the observing strategy, the photometric techniques, and the upcoming data products from this survey and present preliminary results obtained from the analysis of the initial set of near-infrared observations.

  4. DETERMINING INCLINATIONS OF ACTIVE GALACTIC NUCLEI VIA THEIR NARROW-LINE REGION KINEMATICS. I. OBSERVATIONAL RESULTS

    SciTech Connect

    Fischer, T. C.; Crenshaw, D. M.; Kraemer, S. B.; Schmitt, H. R.

    2013-11-01

    Active galactic nuclei (AGNs) are axisymmetric systems to first order; their observed properties are likely strong functions of inclination with respect to our line of sight (LOS). However, except for a few special cases, the specific inclinations of individual AGNs are unknown. We have developed a promising technique for determining the inclinations of nearby AGNs by mapping the kinematics of their narrow-line regions (NLRs), which are often easily resolved with Hubble Space Telescope [O III] imaging and long-slit spectra from the Space Telescope Imaging Spectrograph. Our studies indicate that NLR kinematics dominated by radial outflow can be fit with simple biconical outflow models that can be used to determine the inclination of the bicone axis, and hence the obscuring torus, with respect to our LOS. We present NLR analysis of 53 Seyfert galaxies and the resulting inclinations from models of 17 individual AGNs with clear signatures of biconical outflows. Our model results agree with the unified model in that Seyfert 1 AGNs have NLRs inclined further toward our LOS than Seyfert 2 AGNs. Knowing the inclinations of these AGN NLRs, and thus their accretion disk and/or torus axes, will allow us to determine how their observed properties vary as a function of polar angle. We find no correlation between the inclinations of the AGN NLRs and the disks of their host galaxies, indicating that the orientation of the gas in the torus is independent of that of the host disk.

  5. HUBBLE TARANTULA TREASURY PROJECT: UNRAVELING TARANTULA'S WEB. I. OBSERVATIONAL OVERVIEW AND FIRST RESULTS

    SciTech Connect

    Sabbi, E.; Anderson, J.; Van der Marel, R. P.; Aloisi, A.; De Mink, S. E.; Gordon, K.; Koekemoer, A. M.; Panagia, N.; Lennon, D. J.; Boyer, M. L.; Cignoni, M.; De Marchi, G.; Evans, C. J.; Gallagher, J. S. III; Ryon, J. E.; Gouliermis, D. A.; Grebel, E. K.; Larsen, S. S.; and others

    2013-09-15

    The Hubble Tarantula Treasury Project (HTTP) is an ongoing panchromatic imaging survey of stellar populations in the Tarantula Nebula in the Large Magellanic Cloud that reaches into the sub-solar mass regime (<0.5 M{sub Sun }). HTTP utilizes the capability of the Hubble Space Telescope to operate the Advanced Camera for Surveys and the Wide Field Camera 3 in parallel to study this remarkable region in the near-ultraviolet, optical, and near-infrared spectral regions, including narrow-band H{alpha} images. The combination of all these bands provides a unique multi-band view. The resulting maps of the stellar content of the Tarantula Nebula within its main body provide the basis for investigations of star formation in an environment resembling the extreme conditions found in starburst galaxies and in the early universe. Access to detailed properties of individual stars allows us to begin to reconstruct the temporal and spatial evolution of the stellar skeleton of the Tarantula Nebula over space and time on a sub-parsec scale. In this first paper we describe the observing strategy, the photometric techniques, and the upcoming data products from this survey and present preliminary results obtained from the analysis of the initial set of near-infrared observations.

  6. Storytelling Slide Shows to Improve Diabetes and High Blood Pressure Knowledge and Self-Efficacy: Three-Year Results among Community Dwelling Older African Americans

    ERIC Educational Resources Information Center

    Bertera, Elizabeth M.

    2014-01-01

    This study combined the African American tradition of oral storytelling with the Hispanic medium of "Fotonovelas." A staggered pretest posttest control group design was used to evaluate four Storytelling Slide Shows on health that featured community members. A total of 212 participants were recruited for the intervention and 217 for the

  7. Storytelling Slide Shows to Improve Diabetes and High Blood Pressure Knowledge and Self-Efficacy: Three-Year Results among Community Dwelling Older African Americans

    ERIC Educational Resources Information Center

    Bertera, Elizabeth M.

    2014-01-01

    This study combined the African American tradition of oral storytelling with the Hispanic medium of "Fotonovelas." A staggered pretest posttest control group design was used to evaluate four Storytelling Slide Shows on health that featured community members. A total of 212 participants were recruited for the intervention and 217 for the…

  8. Results of the Baikal Experiment on Observations of oscopic Nonlocal Correlations in Reverse Time

    NASA Astrophysics Data System (ADS)

    Korotaev, S. M.; Serdyuk, V. O.; Kiktenko, E. O.; Budnev, N. M.; Gorohov, J. V.

    Although the general theory oscopic quantum entanglement of is still in its infancy, consideration of the matter in the framework of action-at-a distance electrodynamics predicts for the random dissipative processes observability of the advanced nonlocal correlations (time reversal causality). These correlations were really revealed in our previous experiments with some large-scale heliogeophysical processes as the source ones and the lab detectors as the probe ones. Recently a new experiment has been performing on the base of Baikal Deep Water Neutrino Observatory. The thick water layer is an excellent shield against any local impacts on the detectors. The first annual series 2012/2013 has demonstrated that detector signals respond to the heliogeophysical (external) processes and causal connection of the signals directed downwards: from the Earth surface to the Baikal floor. But this nonlocal connection proved to be in reverse time. In addition advanced nonlocal correlation of the detector signal with the regional source-process: the random component of hydrological activity in the upper layer was revealed and the possibility of its forecast on nonlocal correlations was demonstrated. But the strongest oscopic nonlocal correlations are observed at extremely low frequencies, that is at periods of several months. Therefore the above results should be verified in a longer experiment. We verify them by data of the second annual series 2013/2014 of the Baikal experiment. All the results have been confirmed, although some quantitative parameters of correlations and time reversal causal links turned out different due to nonstationarity of the source-processes. A new result is displaying of the advanced response of nonlocal correlation detector to the earthquake. This opens up the prospect of the earthquake forecast on the new physical principle, although further confirmation in the next events is certainly needed. The continuation of the Baikal experiment with expanded program is burning.

  9. Validation of first chemistry mode retrieval results from new limb-imaging FTS GLORIA with correlative MIPAS-STR observations

    NASA Astrophysics Data System (ADS)

    Woiwode, W.; Suminska-Ebersoldt, O.; Oelhaf, H.; Hpfner, M.; Belyaev, G. V.; Ebersoldt, A.; Friedl-Vallon, F.; Groo, J.-U.; Gulde, T.; Kaufmann, M.; Kleinert, A.; Krmer, M.; Kretschmer, E.; Kulessa, T.; Maucher, G.; Neubert, T.; Piesch, C.; Preusse, P.; Riese, M.; Rongen, H.; Sartorius, C.; Schardt, G.; Schnfeld, A.; Schuettemeyer, D.; Sha, M. K.; Stroh, F.; Ungermann, J.; Volk, C. M.; Orphal, J.

    2014-12-01

    We report first chemistry mode retrieval results from the new airborne limb-imaging infrared FTS (Fourier transform spectrometer) GLORIA and comparisons with observations by the conventional airborne limb-scanning infrared FTS MIPAS-STR. For GLORIA, the flights aboard the high-altitude research aircraft M55 Geophysica during the ESSenCe campaign (ESa Sounder Campaign 2011) were the very first in field deployment after several years of development. The simultaneous observations of GLORIA and MIPAS-STR during the flight on 16 December 2011 inside the polar vortex and under the conditions of optically partially transparent polar stratospheric clouds (PSCs) provided us the unique opportunity to compare the observations by two different infrared FTS generations directly. The retrieval results of temperature, HNO3, O3, H2O, CFC-11 and CFC-12 show reasonable agreement of GLORIA with MIPAS-STR and collocated in-situ observations. For the horizontally binned hyperspectral limb-images, the GLORIA sampling outnumbered the horizontal cross-track sampling of MIPAS-STR by up to one order of magnitude. Depending on the target parameter, typical vertical resolutions of 0.5 to 2.0 km were obtained for GLORIA and are typically by factors of 2 to 4 better compared to MIPAS-STR. While the improvement of the performance, characterisation and data processing of GLORIA are subject of ongoing work, the presented first results already demonstrate the considerable gain in sampling and vertical resolution achieved with GLORIA.

  10. Two yeast acid phosphatase structural genes are the result of a tandem duplication and show different degrees of homology in their promoter and coding sequences.

    PubMed Central

    Meyhack, B; Bajwa, W; Rudolph, H; Hinnen, A

    1982-01-01

    We have cloned the structural genes for a regulated ( PHO5 ) and a constitutive ( PHO3 ) acid phosphatase from yeast by transformation and complementation of a yeast pho3 , pho5 double mutant. Both genes are located on a 5.1-kb BamHI fragment. The cloned genes were identified on the basis of genetic evidence and by hybrid selection of mRNA coupled with in vitro translation and immunoprecipitation. Subcloning of partial Sau3A digests and functional in vivo analysis by transformation together with DNA sequence analysis showed that the two genes are oriented in the order (5') PHO5 , PHO3 (3'). While the nucleotide sequences of the two coding regions are quite similar, the putative promoter regions show a lower degree of sequence homology. Partly divergent promoter sequences may explain the different regulation of the two genes. Images Fig. 2. PMID:6329697

  11. Hamamelis in children with skin disorders and skin injuries: results of an observational study.

    PubMed

    Wolff, Helmut H; Kieser, Meinhard

    2007-09-01

    Published clinical experience with hamamelis ointment in children is limited. This observational study included children (age 27 days to 11 years) with minor skin injuries, diaper dermatitis, or localized inflammation of skin. The children received either hamamelis ointment or dexpanthenol ointment in groups at a 3-to-1 ratio. Baseline and post-treatment assessments compared the total scores of predefined signs and symptoms for each condition. Physicians and parents were asked for a global assessment of efficacy and tolerability of the respective treatments at the end of therapy. A total of 309 children were treated (hamamelis n = 231; dexpanthenol n = 78). The treatment groups were comparable regarding demographic data and baseline total scores of signs and symptoms. In all three diagnosis groups, the efficacy of hamamelis and dexpanthenol was shown by a statistically significant and clinically relevant decrease of total scores from baseline to endpoint (p < 0.0001 for each group, Wilcoxon signed-rank test). Overall, the results for the hamamelis and the dexpanthenol groups were similar. Descriptive advantages for the hamamelis group were observed for a number of parameters and diagnosis groups. Both treatments were well tolerated. Ratings of the tolerability of hamamelis were "excellent" or "good" in 99.1% (physicians) and 98.2% (parents) of cases, respectively. The corresponding ratings for dexpanthenol were 97.4 and 92.3%. In conclusion, hamamelis ointment is an effective and safe treatment for certain skin disorders in children up to the age of 11 years. The observed effects are similar to dexpanthenol. PMID:17177071

  12. Review on optical constants of Titan aerosols: Experimental results and modeling/observational data

    NASA Astrophysics Data System (ADS)

    Brass, Coralie; Muoz, Olga; Coll, Patrice; Raulin, Franois

    2014-05-01

    During the last years many studies have been performed to improve the experimental database of optical constants of Titan aerosols. Indeed, the determination of the optical constants of these particles is essential to quantify their capacity to absorb and to scatter solar radiation, and thus to evaluate their role on Titan's radiative balance and climate. The study of optical properties is also crucial to analyze and to better interpret many of Titan's observational data, in particular those acquired during the Cassini-Huygens mission. One way to determine Titan aerosols optical constant is to measure the optical constants of analogues of Titan complex organic material synthesized in the laboratory, usually named Titan's tholins (Sagan and Khare, 1979). But the optical constants depend on the chemical composition, the size and the shape of particles (Raulin et al., 2012). Those three parameters result from the experimental conditions such as energy source, gas mixing ratio, gas pressure, flow rate and irradiation time (Cable et al., 2012). Besides the determination of the refractive index in the laboratory, there are others methods using theoretical models or observational data. Nevertheless, theoretical models are based on laboratory data or/and observational data. The visible - near infrared spectral region of optical constants has been widely studied with laboratory analogues. Comparison of the obtained results suggest that tholins synthesized by Tran et al. (2003) and Majhoub et al. (2012) are the best representative of Titan aerosols with regards to their refractive indexes in this spectral region. The mid-infrared spectral range has been studied only by Imanaka et al. (2012) and slightly by Tran et al. (2003). In that spectral range, Titan tholins do not exhibit the features displayed by Kim and Courtin (2013) from Titan's observations. For spectral region of wavelengths smaller than 0.20m or higher than 25m, only the data from Khare et al. (1984) are available. Therefore it would be very useful to get more laboratory data and especially from Tran et al (2013), Mahjoub et al. (2012) and Imanaka et al. (2012) samples in these spectral regions since their refractive indexes match observational and theoretical data in other spectral ranges. This presentation will critically summarize these recent results and present detailled constraints on the optical constants Titan's aerosols. In addition, specific lacks of data will be highlighted as well as some possible investigations to be carried out to fill these gaps. References: Cable, M. L., et al., 2012. Titan Tholins: Simulating Titan Organic Chemistry in the Cassini-Huygens Era. Chemical Reviews. 112, 1882-1909. Imanaka, H., et al., 2012. Optical constants of Titan tholins at mid-infrared wavelengths (2.5-25 m) and the possible chemical nature of Titan's haze particles. Icarus. 218, 247-261. Khare, B. N., et al., 1984. Optical-Constants of Organic Tholins Produced in a Simulated Titanian Atmosphere - from Soft-X-Ray to Microwave-Frequencies. Icarus. 60, 127-137. Kim, S. J., Courtin, R., 2013. Spectral characteristics of the Titanian haze at 1-5 micron from Cassini/VIMS solar occultation data. Astronomy & Astrophysics. 557, L6. Mahjoub, A., et al., 2012. Influence of methane concentration on the optical indices of Titan's aerosols analogues. Icarus. 221, 670-677. Raulin, F., et al., 2012. Prebiotic-like chemistry on Titan. Chemical Society Reviews. 41, 5380-5393. Sagan, C., Khare, B. N., 1979. Tholins - Organic-Chemistry of Inter-Stellar Grains and Gas. Nature. 277, 102-107. Tran, B. N., et al., 2003. Simulation of Titan haze formation using a photochemical flow reactor - The optical constants of the polymer. Icarus. 165, 379-390. Acknowledgements: We acknowledge support from the French Space Agency (CNES) and the European Space Agency (ESA).

  13. A Wavenumber-Frequency Analysis of Observations and Results of a Chemistry-Climate Model

    NASA Astrophysics Data System (ADS)

    Dameris, M.; Mager, F.

    2003-04-01

    The wavenumber-frequency analysis method has been sparsely used in atmospheric sciences in the last 15 years despite its numerous applications. The method calculates power spectra, coherence and phase of transient large-scale Rossby waves from time series of Fourier coefficients (Hayashi 1977, 1982). At DLR, this method was employed to study how accurate the ECHAM4.L39(DLR)/CHEM chemistry-climate model (Hein et al., 2001) represents these waves in comparison to ECMWF reanalyses and how they change trough different time-slice experiments. The model represents well the observed wave amplitudes not only in the sum over all frequencies but also in the different considered frequency bands. It simultates well the baroclinic character of travelling waves in respect to vertical amplitude growth and inclination. A remarkable feature of the model is its ability to simulate so-called "normal modes" very accurately. Hayashi, Y., 1977: On the coherence between progressive and retrogressive waves and a partition of space-time power-spectra into standing parts. J. Meteor. Soc. Japan, 16, 368-373 Hayashi, Y., 1982: Space-time spectral analysis and its applications to atmospheric waves. J. Meteor. Soc. Japan, 60, 156-171 Hein, R., M. Dameris, C. Schnadt, C. Land, V. Grewe, I. Khler, M. Ponater, R. Sausen, B. Steil, J. Landgraf, and C. Brhl, 2001: Results of an interactively coupled atmospheric chemistry-general circulation model: Comparison with observations. Ann. Geophys., 19, 435-457

  14. Precision of two-color geodimeter measurements: Results from 15 months of observations

    NASA Astrophysics Data System (ADS)

    Langbein, J. O.; Linker, M. F.; McGarr, A. F.; Slater, L. E.

    1987-10-01

    Spectral analysis of the biweekly measurements of line lengths from the 12-baseline network at Pearblossom, California, reveals that the precision of the prototype two-color Geodimeter is σ = [a2 + D2b2]1/2, where a = 0.3 mm and b = 0.12 ppm and D is the length of the baseline. In contrast, the computed precision is overestimated by 15-20% when a secular trend is fit to 15 months of measurements. By using spectral analysis, the variance σ2 can be separated into two components: the frequency independent instrumental precision and a frequency dependent part. Evaluation of the same data with regard to their dependence upon fluctuations in weather reveal that at most, weather makes a second-order contribution of 0.01 ppm to the observed strain changes. This contribution is a factor of 5-10 times smaller than the instrumental precision. Thus the observed strain changes at Pearblossom reported by Langbein et al. (1982) during 1981 are not due to systematic errors resulting from an improper model of refraction in the atmosphere.

  15. The GASS EUCLIPSE Model Intercomparison of the Stratocumulus Transition as Observed During ASTEX: LES Results

    NASA Technical Reports Server (NTRS)

    Van Der Dussen, J. J.; de Roode, S. R.; Ackerman, Andrew Starr; Blossey, P. N.; Bretherton, C. S.; Kurowski, M. J.; Lock, A. P.; Neggers, R. A. J.; Sandu, I.; Siebesma, A. P.

    2013-01-01

    Large-eddy simulations of a Lagrangian transition from a vertically well-mixed stratocumulus-topped boundary layer to a situation in which shallow cumuli penetrate an overlying layer of thin and broken stratocumulus are compared with aircraft observations collected during the Atlantic Stratocumulus Transition Experiment. Despite the complexity of the case and the long simulation period of 40 h, the six participating state-of-the-art models skillfully and consistently represent the observed gradual deepening of the boundary layer, a negative buoyancy flux at the top of the subcloud layer and the development of a double-peaked vertical velocity variance profile. The moisture flux from the subcloud to the stratocumulus cloud layer by cumulus convection exhibits a distinct diurnal cycle. During the night the moisture flux at the stratocumulus cloud base exceeds the surface evaporation flux, causing a net drying of the subcloud layer, and vice versa during daytime. The spread in the liquid water path (LWP) among the models is rather large during the first 12 h. From additional sensitivity experiments it is demonstrated that this spread is mainly attributable to differences in the parameterized precipitation rate. The LWP differences are limited through a feedback mechanism in which enhanced drizzle fluxes result in lower entrainment rates and subsequently a reduced drying at cloud top. The spread is furthermore reduced during the day as cloud layers with a greater LWP absorb more solar radiation and hence evaporate more.

  16. An Elizabethan Survey and Possible Astronomical Observations on the Oregon Coast: Preliminary Results

    NASA Astrophysics Data System (ADS)

    Haramundanis, Katherine; Gaposchkin, E.

    2007-12-01

    We present preliminary results of our investigations of inscribed rocks found along the Oregon Coast. The roughly 30 rocks contain Latin letters, numbers, and other signs. Bawlf (2000), after Costaggini and Schultz (1977), suggested that the artifacts represent a survey and longitude observation made by Francis Drake in 1579 during his circumnavigation. We have analyzed old records and photographs, and made preliminary site visits to evaluate if these suggestions have merit. The artifacts were first seen in the late 19th century by settlers along the Nehalem River and inspired early searches for treasure on the mountainside, which is rugged, rocky, and steep. The nearby wreck of a Spanish galleon confounded the interpretations. The director of the local Tillamook County Pioneer Museum, Wayne Jensen, with an enthusiastic colleague, Don Viles, spent two decades looking for artifacts and commissioned the existing site survey from the Civil Engineering Department of Oregon State University. Both Viles (1982, 1990) and Jensen (1990) published descriptions of the finds and their search methods. We present photographs of several of the larger artifacts, our conclusions about what the site represents and who may have created it, and suggestions about the meaning of some of the markings and artifacts, including calculations for possible astronomical observations. We solicit comments from the audience regarding any similar sites.

  17. A Compact Infrared Space Telescope MIRIS and its Preliminary Observational Results

    NASA Astrophysics Data System (ADS)

    Han, Wonyong; Pyo, Jeonghyun; Kim, Il-Joong; Lee, Dae-Hee; Jeong, Woong-Seob; Moon, Bongkon; Park, Youngsik; Park, Sung-Joon; Lee, Dukhang; Park, Won-Kee; Ko, Kyeongyeon; Kim, Min Gyu; Nam, Uk-Won; Park, Hong-Young; Lee, Hyung Mok; Matsumoto, Toshio

    2015-08-01

    The first Korean infrared space telescope MIRIS (Milti-purpose InfraRed Imaging System) was successfully launched in November 2013, as the main payload of Korean STSAT-3 (Science and Technology Satellite-3). After the initial on-orbit operation for verification, the observations are made with MIRIS for the fluctuation of Cosmic Infrared Background (CIB) and the Galactic Plane survey. For the study of near-infrared background, MIRIS surveyed large areas (> 10° x 10°) around the pole regions: the north ecliptic pole (NEP), the north and south Galactic poles (NGP, SGP), while the NEP region is continually monitored for the instrumental calibration and the zodiacal light study. In addition, the Paschen-α Galactic plane survey has been made with two narrow-band filters (at 1.88 μm and 1.84+1.92 μm) for the study of warm interstellar medium. We plan to continue surveying the entire galactic plane with the latitude of ±3°, and expect to be completed by 2015. The data are still under the stage of reduction and analysis, and guest observations are on-going. We present some of the preliminary results.

  18. Improving Wind Energy Forecasts through Assimilation of New Meteorological Observations: Results from the Wind Forecast Improvement Project (WFIP)

    NASA Astrophysics Data System (ADS)

    Bianco, L.; Wilczak, J. M.; Djalalova, I. V.; Olson, J. B.; Benjamin, S.; Finley, C. A.; Freedman, J. M.; DiMego, G.; Carley, J. R.; Orwig, K.; Cline, J.; Marquis, M.

    2013-12-01

    The U.S. Department of Energy sponsored a joint research project with NOAA and private industry to improve wind energy forecasts, called the Wind Forecast Improvement Project. The key elements of this program have been 1) a one-year deployment of extensive meteorological observing systems in two regions with significant wind energy production, from August 2011-September 2012; 2) assimilation of these observations into the hourly-updated NOAA Rapid Refresh (RAP), run nationwide each hour at 13 km resolution; and 3) evaluation of the benefits of these improved wind forecasts on electrical utility operations, especially for ramp-events in the 0-6 h forecast time-frame. The special observation data sets assimilated are concentrated over the two selected regions of the U.S. and include: 12 wind profiling radars, 12 sodars, 185 instrumented tall towers (40-200m tall), and 400 nacelle anemometers. In this presentation we will describe results from data denial experiments that have been run for limited periods within the WFIP project. The goal of the data denial experiments is to quantitatively document the precise impact that assimilation of the special WFIP data had on model accuracy, by comparing simulations from identical models run with and without the new data. Standard statistical measures show a significant improvement from the assimilation of the new data, and metrics for wind ramp events (including magnitude and phase of the ramps) show an even larger impact of the observations.

  19. The Australian bush fires of February 2009: MIPAS observations and GEM-AQ model results

    NASA Astrophysics Data System (ADS)

    Glatthor, N.; Hpfner, M.; Semeniuk, K.; Lupu, A.; Palmer, P. I.; McConnell, J. C.; Kaminski, J. W.; von Clarmann, T.; Stiller, G. P.; Funke, B.; Kellmann, S.; Linden, A.; Wiegele, A.

    2012-06-01

    On 7 February 2009, and the following days Southeast Australia was devastated by large bush fires, which burned an area of about 3000 km2. This event was extraordinary, because a large number of combustion products was transported into the uppermost troposphere and lower stratosphere within a few days. Various biomass burning products released by the fire were observed by the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) on the ENVISAT satellite. We track the plume using MIPAS C2H2, HCN and HCOOH single-scan measurements on a day-to-day basis. The measurements are compared with a high-resolution model run of the Global Environmental Multiscale-Air Quality (GEM-AQ) model. Generally there is very good agreement between the spatial distribution of measured and modelled pollutants during the first two weeks after the outbreak of the fire even over intercontinental distances. Both MIPAS and GEM-AQ show a fast south-eastward transport of the pollutants to New Zealand within one day. During the following 3-4 days the plume was located north and eastward of New Zealand and centered at altitudes of 15 to 18 km. Thereafter its eastern part was transported eastward at altitudes of 15-16 km, followed by westward transport of its western part at somewhat higher altitudes. On 17 February the eastern part had reached Southern South America and on 20 February the South African west coast. On the latter day a second relic of the plume was observed moving eastward above the Southern Pacific, whereas the westward transported pollutants were located above Australia at altitudes of 18-20 km. First evidence for entry of the pollutants into the stratosphere was found in MIPAS data of 11 February, followed by larger amounts on 17 February and the days thereafter. Between 20 February and the first week of March the stratospheric pollutants above Australia were transported further westward over the Indian Ocean towards Southern Africa.

  20. Titan below Saturn's magnetodisc: Results from 3D hybrid simulations and Cassini MAG observations

    NASA Astrophysics Data System (ADS)

    Simon, S.; Motschmann, U. M.; Neubauer, F. M.; Wennmacher, A.; Saur, J. S.; Dougherty, M. K.

    2009-12-01

    In the idealized picture of Titan's plasma interaction deduced from Voyager 1 data, the ambient magnetic field is assumed to be perpendicular to the moon's orbital plane. However, Cassini observations suggest that the situation is significantly more complex: Titan is typically located below (above) its parent planet's warped and highly dynamic magnetodisc in southern (northern) summer. The magnetic field near Titan's orbit does not only possess a component towards Saturn, but Cassini MAG data obtained in southern summer also suggest the presence of a significant field component along the corotational flow direction. We present observations from the Cassini MAG instrument during the southern summer conditions of the prime mission, illustrating the high variability of the magnetic field conditions along Titan's orbit. Furthermore, by applying a three-dimensional hybrid model (kinetic ions, fluid electrons), we investigate systematically how Titan's plasma interaction is affected by a deviation of the ambient magnetic field from orthogonality. The model also takes into account the vertical gradient of the plasma composition in Saturn's magnetosphere: The heavy ion species are confined to the magnetic equator, whereas above and below, the impinging magnetospheric plasma mainly consists of light hydrogen ions. Our simulations show that introducing a flow-aligned magnetic field component goes along with an asymmetrization of Titan's magnetotail, in addition to the asymmetry that already arises from the large gyroradii of the ion species involved in the interaction. In the vicinity of Titan, the field lines become strongly twisted, permitting the wakeside magnetic lobe structure to even penetrate into the satellite's geometric plasma shadow. However, despite the increased complexity of Titan's magnetic environment, the overall characteristics of the pick-up ion tail remain practically the same as in the case of ideal magnetic field orientation.

  1. Observations on a Slow Burning Regime for Hydrocarbon Droplets - N-Heptane/Air Results

    NASA Technical Reports Server (NTRS)

    Choi, Mun Y.; Dryer, Frederick L.; Haggard, John B., Jr.

    1991-01-01

    Experiments on n-heptane/airdroplet combustion under reduced gravity have served as a benchmark for much of the existing theoretical efforts on the modeling of sphero-synmmetric droplet burning. New experiments conducted in the NASA-Lewis Research Center 2.2 second droptower (at less than 10 exp -5 g) which emphasize the production of sphero-symmetry and low relative droplet/gas convection produce burning rates in air (for about 1 mm droplets) as much as 40-percent lower than the classical result (0.78 sq mm/s). The burning rate is proportional to the measured droplet/gas relative velocity, and the observed functional dependence is much larger than predicted by published convective correlations. New results clearly indicate that the droplet/laboratory velocity does not correspond to the relative droplet/gas velocity. Thus, the convective effects on droplet combustion is not properly characterized by droplet motion alone. Differences in the burning rates are speculated to result from the effects of the accumulated soot as well as the asymmetry (caused by convection) in the temperature and species distributions surrounding the droplet.

  2. Kinetics of polar mesospheric plasma layers: Comparison of theoretical results with observations

    SciTech Connect

    Sodha, M. S.; Misra, Shikha; Mishra, S. K.; Dixit, Amrit

    2011-08-15

    This paper presents an analytical model for the physical understanding of the charge distribution on ice dust particles in plasma layers of polar mesospheric clouds PMCs (Noctilucent clouds and polar mesospheric summer echoes). For the case of pure ice dust (with high work function), the charging of the particles occurs only because of the accretion of electronic and ionic species on the surface of ice grains. The analysis is based on the number and energy balance of constituents and allows the charge to be only an integral multiple (positive or negative) of the electronic charge. Amongst other interesting results, the theory explains the observed charge distribution on pure ice particles and corresponding reduction of electron density (viz., Bite out) in the PMCs.

  3. Tropospheric CO observed with the NAST-I retrieval methodology, analyses, and first results

    NASA Astrophysics Data System (ADS)

    Zhou, Daniel K.; Smith, William L.; Liu, Xu; Li, Jun; Larar, Allen M.; Mango, Stephen A.

    2005-05-01

    High-resolution infrared spectra from aircraft and space-based observations contain information about tropospheric carbon monoxide (CO) as well as other trace species. A methodology for retrieving tropospheric CO from such remotely sensed spectral data has been developed for the National Polar-Orbiting Operational Environmental Satellite System's Airborne Sounder Testbed - Interferometer (NAST-I). CO profiles of the troposphere, together with its thermodynamic properties, are determined by use of a three-stage retrieval approach that combines the algorithms of physically based statistical eigenvector regression, simultaneous and iterative matrix inversion, and single-variable error-minimization CO profile matrix inverse retrieval. The NAST-I is collecting data while it is aboard high-altitude aircraft throughout many field campaigns. Detailed retrieval analyses based on the NAST-I instrument system along with retrieval results from several recent field campaigns are presented to demonstrate NAST-I CO retrieval capability.

  4. Tropospheric CO observed with the NAST-I retrieval methodology, analyses, and first results.

    PubMed

    Zhou, Daniel K; Smith, William L; Liu, Xu; Li, Jun; Larar, Allen M; Mango, Stephen A

    2005-05-20

    High-resolution infrared spectra from aircraft and space-based observations contain information about tropospheric carbon monoxide (CO) as well as other trace species. A methodology for retrieving tropospheric CO from such remotely sensed spectral data has been developed for the National Polar-Orbiting Operational Environmental Satellite System's Airborne Sounder Testbed-Interferometer (NAST-I). CO profiles of the troposphere, together with its thermodynamic properties, are determined by use of a three-stage retrieval approach that combines the algorithms of physically based statistical eigenvector regression, simultaneous and iterative matrix inversion, and single-variable error-minimization CO profile matrix inverse retrieval. The NAST-I is collecting data while it is aboard high-altitude aircraft throughout many field campaigns. Detailed retrieval analyses based on the NAST-I instrument system along with retrieval results from several recent field campaigns are presented to demonstrate NAST-I CO retrieval capability. PMID:15929295

  5. Evaporation over land surfaces - First results from HAPEX-MOBILHY Special Observing Period

    NASA Technical Reports Server (NTRS)

    Andre, Jean-Claude; Goutorbe, Jean-Paul; Bessemoulin, Pierre; Perrier, Alain; Becker, Francois

    1988-01-01

    Preliminary results are presented from the May 7-July 15, 1986 Special Observing Period (SOP) of the HAPEX-MOBILHY program, which examines the hydrological budget and evaporation flux at the scale of a 10,000 sq km GCM grid square to determine soil moisture, surface-energy budgets, and surface hydrology. The SOP used two highly instrumented remote sensing aircraft to obtain detailed measurements of atmospheric fluxes and surface properties. It is noted that the measurements are reliable at spatially local and short time scales, as well as on the monthly time scale. The data base obtained may be used in parametrization schemes against which land-surface water budgets can be tested.

  6. IMPACT, a Coupled Tropospheric/Stratospheric Chemistry Model: Analysis and Comparison of Results to Observations

    SciTech Connect

    Rotman, D; Atherton, C; Bergmann, D; Cameron-Smith, P; Chuang, C; Connell, P; Dignon, J; Franz, A; Grant, K; Mirin, A; Molenkamp, C; Tannahill, J

    2000-12-11

    We have conducted multi-year simulations describing the distributions of important chemical species in both the troposphere and stratosphere using the LLNL IMPACT atmospheric chemistry model. Simulations have been completed using input meteorological data from both a general circulation model (NCAR MACCM3, Middle Atmospheric Community Climate Model Version 3) and analyzed fields (NASA Data Assimilation Office, STRATF product). IMPACT includes modules describing tropospheric and stratospheric processes and emissions to determine species distributions from the surface to approximately 70 kilometers in altitude. We compare results of these simulations with both long term and short term observational data including surface measurements, vertical profiles and others. We contrast the model's ability to simulate important photochemical cycles (CO/CH4/NMHC/NOx/OH/O3, etc) using both input meteorological datasets. In addition, IMPACT simulations driven with analyzed data are compared to ground based and aircraft campaigns.

  7. Global ozone observations from the UARS MLS: An overview of zonal-mean results

    NASA Technical Reports Server (NTRS)

    Froidevaux, Lucien; Waters, Joe W.; Read, William G.; Elson, Lee S.; Flower, Dennis A.; Jarnot, Robert F.

    1994-01-01

    Global ozone observations from the Microwave Limb Sounder (MLS) aboard the Upper Atmosphere Research Satellite (UARS) are presented, in both vertically resolved and column abundance formats. The authors review the zonal-mean ozone variations measured over the two and a half years since launch in September 1991. Well-known features such as the annual and semiannual variations are ubiquitous. In the equatorial regions, longer-term changes are believed to be related to the quasi-biennial oscillation (QBO), with a strong semiannual signal above 20 hPa. Ozone values near 50 hPa exhibit an equatorial low from October 1991 to June 1992, after which the low ozone pattern splits into two subtropical lows (possibly in connection with residual circulation changes tied to the QBO) and returns to an equatorial low in September 1993. The ozone hole development at high southern latitudes is apparent in MLS column data integrated down to 100 hPa, the MLS data reinforce current knowledge of this lower-stratospheric phenomenon by providing a height-dependent view of the variations. The region from 30 deg S to 30 deg N (an area equal to half the global area) shows very little change in the ozone column from year to year and within each year. The most striking ozone changes have occurred at northern midlatitudes, with the October 1992 to July 1993 column values significantly lower than during the prior year. The zonal-mean changes manifest themselves as a slower rate of increase during the 1992/93 winter, and there is some evidence for a lower fall minimum. A recovery occurs during late summer of 1993; early 1994 values are significantly larger than during the two previous winters. The timing and latitudinal extent of the northern midlatitude decreases appear to rule out observed ClO enhancements in the Arctic vortex, with related chemical processing and ozone dilution effects, as a unique cause. Local depletion from ClO-related chemical mechanisms alone is also not sufficient, based on MLS ClO data. The puzzling asymmetric nature of the changes probably requires a dynamical component as an explanation. A combination of effects (including chemical destruction via heterogeneous processes and QBO phasing) apparently needs to be invoked. This dataset will place constraints on future modeling studies, which are required to better understand the source of the observed changes.

  8. Map Showing Earthquake Shaking and Tsunami Hazard in Guadeloupe and Dominica, as a Result of an M8.0 Earthquake on the Lesser Antilles Megathrust

    USGS Multimedia Gallery

    Earthquake shaking (onland) and tsunami (ocean) hazard in Guadeloupe and Dominica, as a result of anM8.0 earthquake on the Lesser Antilles megathrust adjacent to Guadeloupe. Colors onland represent scenario earthquake shaking intensities calculated in USGS ShakeMap software (Wald et al. 20...

  9. Stable Isotopic Variability in the Carbon Cycle: Reconciling Ocean Model Results with Atmospheric Observations

    NASA Astrophysics Data System (ADS)

    Alden, C. B.; White, J. W.; Miller, J. B.

    2009-12-01

    In the face of rising sea levels, species extinction, unpredictable precipitation changes, and other potential impacts of anthropogenic climate change, there is a push for the scientific community to expand our current understanding of the major sources and sinks of global warmings most implicated culprit, CO2. Knowing the mechanisms controlling CO2 sinks and sources will be vital for policy-makers to make informed decisions regarding its mitigation. The stable carbon isotope, 13C, can be used to partition CO2 fluxes into land and ocean components. The major fluxes of this gas (fossil fuel, ocean and land) impose distinctive and predictable fractionation patterns upon the stable isotope ratio, making it an ideal tool for distinguishing between them. One drawback to this method is that photosynthesis and respiration are not contemporaneous, and because the 13C of atmospheric CO2 is being continuously depleted through the burning of 12C-rich fossil fuels (the Suess effect), there is an isotopic disequilibrium flux between CO2 moving into and out of the ocean and land reservoirs. In this study, we take a new approach and seek to reconcile independent estimates of time histories of ocean fluxes with atmospheric observations. We use a combination of atmospheric CO2 and 13CO2 data, fossil fuel emission estimates, and recent ocean model results (from two different approaches) for the ocean CO2 flux, within a box-inverse model as well as a 2D transport model. We calculate time series of land flux, disequilibrium flux and photosynthetic fractionation from 1991 through 2008. Our findings reveal that if ocean variability is as small as is suggested by the ocean model, and the isotopic variability is forced into the disequilibrium flux, then the resulting disequilibrium flux has very large interannual variability (~35 PgC/yr). While large interannual variability in DIS seems incompatible with the Suess effect alone, it could be explained by interannual variations in the photosynthetic fractionation term, ?ab. Interannual variations in relative strength of C3 and C4 productivity and stomatal conductance could change isotopic disequilibrium over large spatial scales, thus helping to explain the otherwise seemingly incongruent nature of the ocean model results and atmospheric observations. We produce several end-member scenarios, of varying spatial resolutions, in which photosynthetic fractionation and C4 fraction of net ecosystem exchange (NEE) absorb all variability expressed in the disequilibrium flux results. We next compare our estimates of the photosynthetic fractionation and C3/C4 changes with independent climate indicators, such as precipitation and temperature anomalies, drought indices, and soil moisture.

  10. Storm time observations of electromagnetic ion cyclotron waves at geosynchronous orbit: GOES results

    NASA Astrophysics Data System (ADS)

    Fraser, B. J.; Grew, R. S.; Morley, S. K.; Green, J. C.; Singer, H. J.; Loto'aniu, T. M.; Thomsen, M. F.

    2010-05-01

    Electromagnetic ion cyclotron (EMIC) waves may contribute to ring current ion and radiation belt electron losses, and theoretical studies suggest these processes may be most effective during the main phase of geomagnetic storms. However, ground-based signatures of EMIC waves, Pc1-Pc2 geomagnetic pulsations, are observed more frequently during the recovery phase. We investigate the association of EMIC waves with various storm phases in case and statistical studies of 22 geomagnetic storms over 1996-2003, with an associated Dst < -30 nT. High-resolution data from the GOES 8, 9, and 10 geosynchronous satellite magnetometers provide information on EMIC wave activity in the 0-1 Hz band over ±3 days with respect to storm onset, defined as commencement of the negative excursion of Dst. Thirteen of 22 storms showed EMIC waves occurring during the main phase. In case studies of two storms, waves were seen with higher intensity in the main phase in one and the recovery phase in the other. Power spectral densities up to 500 nT2 Hz-1 were similar in prestorm, storm, and early recovery phases. Superposed epoch analysis of the 22 storms shows 78% of wave events during the main phase occurred in the He+ band. After storm onset the main phase contributed only 29% of events overall compared to 71% during recovery phase, up to 3 days. Some differences between storms were found to be dependent on the solar wind driver. Plasma plumes or an inflated plasmasphere may contribute to enhancing EMIC wave activity at geosynchronous orbit.

  11. Surface Tension and Viscosity Measurements in Microgravity: Some Results and Fluid Flow Observations during MSL-1

    NASA Technical Reports Server (NTRS)

    Hyer, Robert W.; Trapaga, G.; Flemings, M. C.

    1999-01-01

    The viscosity of a liquid metal was successfully measured for the first time by a containerless method, the oscillating drop technique. This method also provides a means to obtain a precise, non-contact measurement of the surface tension of the droplet. This technique involves exciting the surface of the molten sample and then measuring the resulting oscillations; the natural frequency of the oscillating sample is determined by its surface tension, and the damping of the oscillations by the viscosity. These measurements were performed in TEMPUS, a microgravity electromagnetic levitator (EML), on the Space Shuttle as a part of the First Microgravity Science Laboratory (MSL-1), which flew in April and July 1997 (STS-83 and STS-94). Some results of the surface tension and viscosity measurements are presented for Pd82Si18. Some observations of the fluid dynamic characteristics (dominant flow patterns, turbulent transition, cavitation, etc.) of levitated droplets are presented and discussed together with magnetohydrodynamic calculations, which were performed to justify these findings.

  12. Fireball observations in central Europe and western Australia: instruments, methods, and results

    NASA Astrophysics Data System (ADS)

    Spurny, P.

    2012-01-01

    Penetration of larger meteoroids through the atmosphere which gives rise to spectacular luminous events - fireballs or even superbolides - is of the greatest interest. Their registrations, especially photographic and newly also photoelectric recordings, provide excellent means to examine physical properties as well as the temporal and spatial distribution of extraterrestrial matter in near-Earth space. The most efficient tools for registration of these very scarce events are the fireball networks: systems covering large areas of the Earth's surface, with multiple camera stations designed to image a large fraction of the night sky. Such camera networks for fireball observations have been set up in several nations at various times in the past (European Fireball Network (EN) in the Czech Republic, Germany, Austria, and Slovakia; the Prairie Network in the USA; and the Meteorite Observation and Recovery Project (MORP) in Canada). Of these networks, only the European fireball network is still in operation, and this continuously since it was started up, but recently new networks were established in South-West Australia and in Ontario, Canada. The two main scientific aims of all these programs remain the same as in the very beginning - first, to constrain the flux of extraterrestrial material to the Earth over a range of masses, and second, to provide a statistically significant group of meteorites with accurate orbits. This contribution was focused on the current work and some particular recent results from the European Fireball Network, especially from its Czech part (current status is described, for example, by Spurny et al., 2006) and from the Desert Fireball Network in the Nullarbor Plains of South-West Australia (Bland, 2004; Spurny et al., 2012; and Bland et al., 2012). The mode of operation of both networks and the analysis methods used were described in detail and illustrated by some examples. Similarly, the most important recent results, especially from the Desert Fireball Network, such as the Bunburra Rockhole and Mason Gully meteorite falls, were presented in detail. These results are already published by Spurny et al. (2011, Mason Gully; 2012, Bunburra Rockhole) and Bland et al. (2009, Bunburra Rockhole).

  13. Mathematical modelling in Matlab of the experimental results shows the electrochemical potential difference - temperature of the WC coatings immersed in a NaCl solution

    NASA Astrophysics Data System (ADS)

    Benea, M. L.; Benea, O. D.

    2016-02-01

    The method used for purchasing the corrosion behaviour the WC coatings deposited by plasma spraying, on a martensitic stainless steel substrate consists in measuring the electrochemical potential of the coating, respectively that of the substrate, immersed in a NaCl solution as corrosive agent. The mathematical processing of the obtained experimental results in Matlab allowed us to make some correlations between the electrochemical potential of the coating and the solution temperature is very well described by some curves having equations obtained by interpolation order 4.

  14. Transitioning from preclinical to clinical chemopreventive assessments of lyophilized black raspberries: interim results show berries modulate markers of oxidative stress in Barrett's esophagus patients.

    PubMed

    Kresty, Laura A; Frankel, Wendy L; Hammond, Cynthia D; Baird, Maureen E; Mele, Jennifer M; Stoner, Gary D; Fromkes, John J

    2006-01-01

    Increased fruit and vegetable consumption is associated with decreased risk of a number of cancers of epithelial origin, including esophageal cancer. Dietary administration of lyophilized black raspberries (LBRs) has significantly inhibited chemically induced oral, esophageal, and colon carcinogenesis in animal models. Likewise, berry extracts added to cell cultures significantly inhibited cancer-associated processes. Positive results in preclinical studies have supported further investigation of berries and berry extracts in high-risk human cohorts, including patients with existing premalignancy or patients at risk for cancer recurrence. We are currently conducting a 6-mo chemopreventive pilot study administering 32 or 45 g (female and male, respectively) of LBRs to patients with Barrett's esophagus (BE), a premalignant esophageal condition in which the normal stratified squamous epithelium changes to a metaplastic columnar-lined epithelium. BE's importance lies in the fact that it confers a 30- to 40-fold increased risk for the development of esophageal adenocarcinoma, a rapidly increasing and extremely deadly malignancy. This is a report on interim findings from 10 patients. To date, the results support that daily consumption of LBRs promotes reductions in the urinary excretion of two markers of oxidative stress, 8-epi-prostaglandin F2alpha (8-Iso-PGF2) and, to a lesser more-variable extent, 8-hydroxy-2'-deoxyguanosine (8-OHdG), among patients with BE. PMID:16800781

  15. Melt Undercutting and Calving from Tidewater Glaciers: Observations and Model Results

    NASA Astrophysics Data System (ADS)

    Benn, D.; Cook, S.; strm, J. A.; Luckman, A. J.; Zwinger, T.

    2014-12-01

    Dynamic models incorporating crevasse-depth calving laws have enjoyed considerable success in simulating observed behavior of tidewater glaciers. Such models are based on the assumption that longitudinal strain rates exert a first-order control on calving, and that penetration of surface and basal crevasses provides the ultimate constraint on glacier extent. However, 'second-order' processes such as melt undercutting may significantly amplify calving rates, initiating seasonal and longer-term glacier retreats. We present high temporal and spatial resolution TerraSAR-X data from Svalbard that indicate a strong annual cycle in calving rates, peaking in September-October coincident with maximum fjord temperatures. This pattern is consistent for all studied glaciers irrespective of glacier activity (fast, slow, surging or quiescent), and we conclude that in Svalbard calving is paced by melt-undercutting followed by mechanical destabilization of the ice tongue. Although parameterizations of melt undercutting are included in many models employing the crevasse-depth calving criterion, amplification of calving by melt undercutting (the 'O'Leary Effect') has not been rigorously analyzed or tested against observations. We take a novel approach to this problem, and couple the finite element model Elmer-Ice with a discrete particle model (DPM) to explore in detail the links between melt undercutting and failure of the ice tongue. Employing glacier front geometries representative of Kronebreen (Svalbard), Columbia Glacier (Alaska) and Helheim Glacier (Greenland), we use Elmer-Ice to simulate progressive undercutting of the ice front by melting. At selected time steps, the model geometry was exported into the DPM, and runs conducted to study fracturing and calving behavior using different values of the fracture stress. We quantify the O'Leary Effect for different geometries, and propose a modified calving law incorporating the effects of melt-undercutting. The results highlight the importance of accounting for the impact of melt undercutting on calving losses in dynamic calving models.

  16. On the origin of 150-km echoes: Recent observational results and current understanding

    NASA Astrophysics Data System (ADS)

    Patra, Amit

    2012-07-01

    Discovered nearly 45 years ago, the so-called 150-km echoing phenomenon continues to be a puzzle. These are the coherent radar echoes coming from the height region of 140-180 km during daytime and are of special interest to the ionospheric scientists since they are very useful means for estimating the daytime electric fields, a crucial parameter for studying daytime electrodynamics and plasma physics, and can be observed by radar with moderate sensitivity. Although the 150-km echoes are being regularly used for studying low latitude electrodynamics, it is a bit awkward using them in the scientific work without knowing their origin. This paper is meant to present and discuss new results obtained from Gadanki (13.5o N, 79.2o E, mag. lat. 6.5o N), India to elucidate the underlying physical processes, not considered before. Two new findings, one obtained during the passage of a solar eclipse and another linked with the intermediate layer type descending properties of 150-km echoes, clearly indicate the role of electron density gradient in generating the irregularities responsible for the 150-km radar echoes, not envisioned before. Given the fact that Gadanki is located at magnetically low latitude, it is proposed that the descending echoing layers are produced by interchange instability on the gradient of daytime descending ion layer formed by meridional wind shear associated with tidal/gravity waves quite similar to that observed during nighttime. Comparative anatomy of daytime 150-km echoes and nighttime intermediate layer echoes will also be presented and discussed in an effort to have a deeper understanding on the underlying instability processes.

  17. Program of the Antarctic Syowa MST/IS radar: Results from Continuous Observations

    NASA Astrophysics Data System (ADS)

    Nakamura, Takuji; Tsutsumi, Masaki; Saito, Akinori; Sato, Toru; Tomikawa, Yoshihiro; Nishimura, Koji; Yamagishi, Hisao; Yamanouchi, Takashi; Sato, Kaoru; Kohma, Masaki

    The PANSY radar has been installed at Syowa Station (6900S, 3935E) as the first Mesosphere-Stratosphere-Troposphere/Incoherent Scatter (MST/IS) radar in the Antarctic. It is a monostatic coherent pulse Doppler radar operating at 47 MHz VHF, consisting of an active phased array of 1,045 Yagi antennas and the same number of transmitter/receiver (TR) modules obtaining a total peak output power of 500 kW. The first stage of the radar install was carried out in early 2011, and since April 2012 the radar has been continuously operated with 228 antennas and modules. The full radar system operation will start in 2015. The primary objectives of the radar to clarify the role of atmospheric gravity waves at high latitudes in the momentum budget of the global circulation in the troposphere and middle atmosphere, and to explore the dynamical aspects of unique polar phenomena such as polar mesospheric/stratospheric clouds. The katabatic winds as a branch of Antarctic tropospheric circulation and as an important source of gravity waves are also of special interest. Furthermore, strong and sporadic energy inputs from the magnetosphere by energetic particles and field-aligned currents can be quantitatively assessed by the broad height coverage of the radar from the lower troposphere to the upper ionosphere. In this paper we will report the scientific objectives of the project, technical descriptions, and the results of observations in the troposphere, stratosphere and mesosphere to date, including observations regarding severe snow storms, gravity waves, multiple tropopauses, and polar mesosphere summer/winter echoes.

  18. NOVAC - Network for Observation of Volcanic and Atmospheric Change, First Installations and Results

    NASA Astrophysics Data System (ADS)

    Galle, B.; Platt, U.; Vanroozendael, M.; Oppenheimer, C.; Hansteen, T.; Boudon, G.; Burton, M.; Delgado, H.; Strauch, W.; Duarte, E.; Garzon, G.; Pullinger, C.; Kasereka, M.; Molina, L.; Carn, S.; Samaniego, P.; Sanchez, E.; Inguaggiato, S.

    2007-05-01

    The NOVAC project, funded by European Union, was started in October 2005 with the aim to establish a global network of stations for the quantitative measurement of volcanic gas emissions. The network is based on a novel type of instrument, the Scanning Dual-beam mini-DOAS. Primarily the instruments will be used to provide new parameters in the toolbox of observatories for gas emission estimates, geophysical research and hazard assessment. In addition, data are exploited for other scientific purposes, e.g. global estimates of volcanic gas emissions, regional to global statistical analysis, and studies of atmospheric chemistry. In particular large scale validation of satellite measurements of volcanic gas emissions will be possible, bringing spaceborne observation volcanoes a significant step forward. The Scanning Dual-beam Mini-DOAS instrument is capable of real-time automatic, unattended measurement of the total emission fluxes of SO2 and BrO from a volcano with better then 5 minutes time resolution during daylight. The high time-resolution of the data enables correlations with other geophysical data, e.g. seismicity, thus significantly extending the information available for real-time hazard assessment and research. By comparing high time resolution gas emission data with emissions from neighboring volcanoes on different geographical scales, or with other geophysical events (earthquakes, tidal waves) mechanisms of volcanic forcing may be revealed. The spectra recorded by the instrument will also be used to derive data that complement global observation networks related to climate change and stratospheric ozone depletion research. The consortium encompasses observatories of 20 volcanoes from five continents, including some of the most active and strongest degassing volcanoes in the world. The project will be presented as well as first results from the recent installations on San Cristobal, Masaya, Tungurahua and Galeras volcanoes.

  19. Precipitation extremes over La Plata Basin - Review and new results from observations and climate simulations

    NASA Astrophysics Data System (ADS)

    Cavalcanti, I. F. A.; Carril, A. F.; Penalba, O. C.; Grimm, A. M.; Menndez, C. G.; Sanchez, E.; Cherchi, A.; Srensson, A.; Robledo, F.; Rivera, J.; Pntano, V.; Bettolli, L. M.; Zaninelli, P.; Zamboni, L.; Tedeschi, R. G.; Dominguez, M.; Ruscica, R.; Flach, R.

    2015-04-01

    Monthly and daily precipitation extremes over La Plata Basin (LPB) are analyzed in the framework of the CLARIS-LPB Project. A review of the studies developed during the project and results of additional research are presented and discussed. Specific aspects of analysis are focused on large-scale versus local processes impacts on the intensity and frequency of precipitation extremes over LPB, and on the assessment of specific wet and dry spell indices and their changed characteristics in future climate scenarios. The analysis is shown for both available observations of precipitation in the region and ad-hoc global and regional models experiments. The Pacific, Indian and Atlantic Oceans can all impact precipitation intensity and frequency over LPB. In particular, considering the Pacific sector, different types of ENSO events (i.e. canonical vs Modoki or East vs Central) have different influences. Moreover, model projections indicate an increase in the frequency of precipitation extremes over LPB during El Nio and La Nin events in future climate. Local forcings can also be important for precipitation extremes. Here, the feedbacks between soil moisture and extreme precipitation in LPB are discussed based on hydric conditions in the region and model sensitivity experiments. Concerning droughts, it was found that they were more frequent in the western than in the eastern sector of LPB during the period of 1962-2008. On the other hand, observations and model experiments agree in that the monthly wet extremes were more frequent than the dry extremes in the northern and southern LPB sectors during the period 1979-2001, with higher frequency in the south.

  20. Orbit and Gravity Field Solutions from Swarm GPS Observations - First Result

    NASA Astrophysics Data System (ADS)

    Jaeggi, A.; Dahle, C.; Arnold, D.; Bock, H.; Flechtner, F.

    2014-12-01

    Although ESA's Earth Explorer Mission Swarm is primarily dedicated to measure the Earth's magnetic field, it may also serve as a gravity field mission. Equipped with GPS receivers, accelerometers, star-tracker assemblies and laser retro-reflectors, the three Swarm satellites are potentially capable to be used as a high-low satellite-to-satellite tracking (hl-SST) observing system, following the missions CHAMP (first single-satellite hl-SST mission), GRACE (twin-satellite mission with additional ultra-precise low-low SST and GOCE (single-satellite mission additionally equipped with a gradiometer). GRACE, dedicated to measure the time-variability of the gravity field, is the only mission still in orbit, but its lifetime will likely end before launch of its follow-on mission GRACE-FO in August 2017 primarily due to aging of the onboard batteries after meanwhile more than 12 years of operation. Swarm is probably a good candidate to provide time-variable gravity field solutions and to close a potential gap between GRACE and GRACE-FO. Consisting of three satellites, Swarm also offers to use inter-satellite GPS-derived baselines as additional observations. However, as of today it is not clear if such information will substantially improve the gravity field solutions. Nevertheless, the properties of the Swarm constellation with two lower satellites flying in a pendulum-like orbit and a slightly differently inclined third satellite at higher altitude still represent a unique observing system raising expectations at least compared to CHAMP derived time-variable gravity field solutions. Whatever processing method will be applied for Swarm gravity field recovery, its success strongly depends on the quality of the Swarm Level 1b data as well as the quality of the derived Swarm orbits. With first Level 1b data sets available since mid of May 2014 (excluding accelerometer data), first results for Swarm orbits and baselines, as well as Swarm gravity field solutions are presented here. The latter are also compared to GRACE GPS hl-SST solutions based on the same amount of data and processing methods.

  1. The results of observations of the twilight fireballs over Kyiv and their classification

    NASA Astrophysics Data System (ADS)

    Churyumov, K. I.; Steklov, A. F.; Vidmachenko, A. P.; Steklov, E. A.; Dashkiev, G. N.

    2015-09-01

    Fireball - a meteoritic phenomenon brighter -4m. If such dust track illuminated by rays of the just-gone sun, it can be visible as a bright silvery stripe against the twilight sky. We therefore called them twilight fireballs. In recent years the US geostationary satellites has repeatedly registered in Earth's atmosphere flash brighter -17m. The characteristic initial size of such stony body is 1-3 m. If these meteoroids are composed of ice and snow (fragments of comet nuclei), their size increases up to tens of meters. After the event of Chelyabinsk bolide researchers suggested that such sight should be expected in 100-150 years. But in the evening of 29.03.2013 we were able to register a rare phenomenon of three fireball traces in the twilight sky over Kiev. They were formed during the 12 seconds after falling of three large fragments perhaps of cometary nucleus [1]. Traces were visible for about 20 minutes. In the evening of 10/27/2013 we again observed a falling of bright (-16m) fireball over Kiev. Its dust trail was visible about 50 minutes. Over 2 years we have received several thousands of different "tracks in the sky." We propose [2] to classify them into the following four types: AM - aerometeorological, AT - aero-technical, AK - aerospace, others - not yet classified. A detailed study of our photo library allows to make such conclusions. 1. We have discovered a new class of astronomical objects - fragments of cometary nuclei, "scratching" the Earth (erdgreyzery). 2. is proposed and tested a new class of effective twilight observations of fireballs. References. [1] Churjumov K. I., Vidmachenko A. P., Steklov A. F., Steklov E. A. Three bright bolides in Kiev sky on 29 March 2013 // Conference "Meteoroids 2013". Program and abstracts. 26-30 Aug. 2013, Poznan;, Poland P. 77. [2] Churyumov K. I., Steklov O. F., Vidmachenko A. P., Steklov E. A. Traces on sky: the classification and the results of regular observations of twilight fireballs // Astronomical School`s Report. - 2014. Vol. 10, No. 1., p.37-42.

  2. Observing Supercells with Unmanned Aircraft: Results from the UAS Component of VORTEX-2

    NASA Astrophysics Data System (ADS)

    Houston, A. L.; Argrow, B.; Frew, E.

    2010-12-01

    In the second Verification of the Origins of Rotation in Tornadoes Experiment (VORTEX-2) autonomous unmanned aircraft were used for the first time to collect in-situ observations in close proximity to supercells. The use of unmanned aircraft to collect data significant to stormscale research has long been recognized. However, collecting these data requires aircraft operation beyond the visual line of sight of the controller which necessitates aircraft autonomy. An autonomous unmanned aircraft requires a significantly more complex command and control system and elicits more scrutiny by airspace regulatory agencies. Therefore, while the potential utility of unmanned aircraft systems (UAS, the unmanned aircraft along with the communications and logistics infrastructure required for their operation) for stormscale research may be obvious, the engineering and regulatory hurdles that must be overcome for their use are significant. Surmounting these engineering and regulatory hurdles was the principal objective of the UAS component of VORTEX-2. Regulatory hurdles prevented UAS operations in the first year of VORTEX-2. However, the Federal Aviation Administration (tasked with regulating all UAS operations) granted the UAS group certificates of authorization (CoA) to fly for all of year-2 over northeast CO, southwest NE, and northwest KS. The majority of the engineering hurdles involved the communication system necessary to 1) command and control the aircraft through its on-board autopilot and 2) direct ground-based vehicles required to remain compliant with FAA regulations. Testing during both year-1 and -2 yielded a robust communication system. Lessons learned from interactions with the FAA along with an overview of the communication system will be presented at the conference. Scientifically, the UAS in VORTEX-2 was tasked with collecting in-situ observations of the temperature and moisture above the surface across the rear flank gust front (RFGF) and within the rear flank downdraft (RFD). Despite the relatively small region approved for UAS operations, 6 flights were conducted in the vicinity of supercells during year-2 of VORTEX-2: 6 May, 26 May, 6 June, 7 June, 9 June, and 10 June. Of these flights, three (6 June, 9 June, and 10 June) collected observations across the RFGF and within the RFD. Results from the VORTEX-2 flights along with an outlook towards possible future applications of UAS for stormscale research will be presented at the conference.

  3. Renegotiating the Peer Review Process: Disseminating Observational Results in an Age of Instant Access

    NASA Astrophysics Data System (ADS)

    Duerr, R.

    2006-12-01

    Science and technology impact nearly every aspect of life in the developed world today. It is not surprising then, that events in science and technology make news. On the flip side, the scientific community is increasingly exhorted to make their research relevant, as well as to communicate their results to the broader public. On another front, a combination of forces, including the rise of advanced computing and telecommunications technologies, has dramatically increased the amount of scientific data and information that are available to the public. With increasing frequency, some types of observationally derived data are available more or less immediately upon creation. Given the nature of the news process, if the science community is to affect how the public interprets newly available information, they must be ready to explain interesting results as soon as the data become available. Yet, the science community expects that results will be published in the peer-reviewed literature prior to wide dissemination. The publication and peer review process takes time, even in this age of electronic access. Thus, the norms of science and the need for timely communication with the public are often in conflict. There may be areas of scientific work where resolving this inherent conflict is unimportant. However, in any arena where public interest in these data or their interpretation is large, resolution of the conflict is necessary if the special knowledge and skills of the science community are to play a role in the formation of public opinion or policy. The science community is only now beginning to address this fundamental conflict. This paper examines a newsworthy case from the recent past where the conflict between immediacy and the scientific process is clear in order to illuminate one resolution strategy currently in use within a portion of the science community a process akin to the normal literature review process.

  4. MIPAS observations and GEM-AQ model results of the Australian bush fires of February 2009

    NASA Astrophysics Data System (ADS)

    Glatthor, Norbert; Hpfner, Michael; Semeniuk, Kirill; Lupu, Alexandru; Palmer, Paul; McConnell, Jack; Kaminski, Jacek; von Clarmann, Thomas; Stiller, Gabriele; Funke, Bernd; Kellmann, Sylvia; Linden, Andrea; Wiegele, Andreas

    2013-04-01

    Starting on February 7, 2009, Southeast Australia was devastated by large bush fires, which burned an area of about 3000 km2 on this day alone. This event was extraordinary, because a large number of combustion products was transported into the uppermost troposphere and lower stratosphere within a few days. Various biomass burning products released by the fire were observed by the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) on the ENVISAT satellite. We tracked the plume using MIPAS C2H2, HCN and HCOOH single-scan measurements on a day-to-day basis. The measurements were compared with a high-resolution model run of the Global Environmental Multiscale-Air Quality (GEM-AQ) model. Generally there is good agreement between the spatial distribution of measured and modelled pollutants. Both MIPAS and GEM-AQ show a fast south-eastward transport of the pollutants to New Zealand within one day. During the following 3-4 days the plume remained north-eastward of New Zealand and was located at altitudes of 15 to 18 km. Thereafter its lower part was transported eastward, followed by westward transport of its upper part. On February 17 the eastern part had reached southern South America and on February 20 the central Southern Atlantic. On the latter day a second relic of the plume was observed moving eastward above the Southern Pacific. Between February 20 and the first week of March the upper part of the plume was transported westward over Australia and the Indian Ocean towards Southern Africa. First evidence for entry of the pollutants into the stratosphere was found in MIPAS data of February 11, followed by larger amounts on February 17 and the days thereafter. From MIPAS data, C2H2/HCN and HCOOH/HCN enhancement ratios of 0.76 and 2.16 were calculated for the first days after the outbreak of the fires, which are considerably higher than the emission ratios assumed for the model run and at the upper end of values found in literature. From the temporal decrease of the enhancement ratios, mean lifetimes of 16-17 days and of 8-9 days were calculated for measured C2H2 and HCOOH. The respective lifetimes calculated from the model data are 18 and 12 days.

  5. The Australian bushfires of February 2009: MIPAS observations and GEM-AQ model results

    NASA Astrophysics Data System (ADS)

    Glatthor, N.; Hpfner, M.; Semeniuk, K.; Lupu, A.; Palmer, P. I.; McConnell, J. C.; Kaminski, J. W.; von Clarmann, T.; Stiller, G. P.; Funke, B.; Kellmann, S.; Linden, A.; Wiegele, A.

    2013-02-01

    Starting on 7 February 2009, southeast Australia was devastated by large bushfires, which burned an area of about 3000 km2 on this day alone. This event was extraordinary, because a large number of combustion products were transported into the uppermost troposphere and lower stratosphere within a few days. Various biomass burning products released by the fire were observed by the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) on the Envisat satellite. We tracked the plume using MIPAS C2H2, HCN and HCOOH single-scan measurements on a day-to-day basis. The measurements were compared with a high-resolution model run of the Global Environmental Multiscale Air Quality (GEM-AQ) model. Generally there is good agreement between the spatial distribution of measured and modelled pollutants. Both MIPAS and GEM-AQ show a fast southeastward transport of the pollutants to New Zealand within one day. During the following 3-4 days, the plume remained northeastward of New Zealand and was located at altitudes of 15 to 18 km. Thereafter its lower part was transported eastward, followed by westward transport of its upper part. On 17 February the eastern part had reached southern South America and on 20 February the central South Atlantic. On the latter day a second relic of the plume was observed moving eastward above the South Pacific. Between 20 February and the first week of March, the upper part of the plume was transported westward over Australia and the Indian Ocean towards southern Africa. First evidence for entry of the pollutants into the stratosphere was found in MIPAS data of 11 February, followed by larger amounts on 17 February and the days thereafter. From MIPAS data, C2H2/HCN and HCOOH/HCN enhancement ratios of 0.76 and 2.16 were calculated for the first days after the outbreak of the fires, which are considerably higher than the emission ratios assumed for the model run and at the upper end of values found in literature. From the temporal decrease of the enhancement ratios, mean lifetimes of 16-20 days and of 8-9 days were calculated for measured C2H2 and HCOOH. The respective lifetimes calculated from the model data are 18 and 12 days.

  6. A second generation cervico-vaginal lavage device shows similar performance as its preceding version with respect to DNA yield and HPV DNA results

    PubMed Central

    2013-01-01

    Background Attendance rates of cervical screening programs can be increased by offering HPV self-sampling to non-attendees. Acceptability, DNA yield, lavage volumes and choice of hrHPV test can influence effectiveness of the self-sampling procedures and could therefore play a role in recruiting non-attendees. To increase user-friendliness, a frequently used lavage sampler was modified. In this study, we compared this second generation lavage device with the first generation device within similar birth cohorts. Methods Within a large self-sampling cohort-study among non-responders of the Dutch cervical screening program, a subset of 2,644 women received a second generation self-sampling lavage device, while 11,977 women, matched for age and ZIP-code, received the first generation model. The second generation device was different in shape, color, lavage volume, and packaging, in comparison to its first generation model. The Cochran’s test was used to compare both devices for hrHPV positivity rate and response rate. To correct for possible heterogeneity between age and ZIP codes in both groups the Breslow-Day test of homogeneity was used. A T-test was utilized to compare DNA yields of the obtained material in both groups. Results Median DNA yields were 90.4 μg/ml (95% CI 83.2-97.5) and 91.1 μg/ml (95% CI 77.8-104.4, p= 0.726) and hrHPV positivity rates were 8.2% and 6.9% (p= 0.419) per sample self-collected by the second - and the first generation of the device (p= 0.726), respectively. In addition, response rates were comparable for the two models (35.4% versus 34.4%, p= 0.654). Conclusions Replacing the first generation self-sampling device by an ergonomically improved, second generation device resulted in equal DNA yields, comparable hrHPV positivity rates and similar response rates. Therefore, it can be concluded that the clinical performance of the first and second generation models are similar. Moreover, participation of non-attendees in cervical cancer screening is probably not predominantly determined by the type of self-collection device. PMID:23639287

  7. First Results of Atmospheric Trace Gases in and around New Delhi using mobile MAX-DOAS observations

    NASA Astrophysics Data System (ADS)

    Shaiganfar, R.; Beirle, S.; Marbach, T.; Wagner, T.; Sharma, M.; Chauhan, A.; Singh, R.

    2010-12-01

    . Megacities are localized, heterogeneous and variable sources of air pollutants, greatly influence air quality and have direct influence on climate. Within the European project MEGAPOLI, in month of April 2010, we carried out mobile MAX-DOAS measurements in and around Delhi and made comparison with satellite data. The MAX-DOAS was mounted on a car. The aim of the project was to characterize and quantify pollutants. The mobile observations were conducted in and around New Delhi along circles of different radii. The analysis of MAX-DOAS, satellite observations and meteorological data, is used to quantify the total emissions of trace gases like NO2, HCHO or Glyoxal. The results obtained from the detailed analysis are first time compared with the satellite data. The ground and satellite data show a good correlation over Delhi, capital of India.

  8. Value of Fused 18F-Choline-PET/MRI to Evaluate Prostate Cancer Relapse in Patients Showing Biochemical Recurrence after EBRT: Preliminary Results

    PubMed Central

    Piccardo, Arnoldo; Paparo, Francesco; Picazzo, Riccardo; Naseri, Mehrdad; Ricci, Paolo; Marziano, Andrea; Bacigalupo, Lorenzo; Biscaldi, Ennio; Rollandi, Gian Andrea; Grillo-Ruggieri, Filippo; Farsad, Mohsen

    2014-01-01

    Purpose. We compared the accuracy of 18F-Choline-PET/MRI with that of multiparametric MRI (mMRI), 18F-Choline-PET/CT, 18F-Fluoride-PET/CT, and contrast-enhanced CT (CeCT) in detecting relapse in patients with suspected relapse of prostate cancer (PC) after external beam radiotherapy (EBRT). We assessed the association between standard uptake value (SUV) and apparent diffusion coefficient (ADC). Methods. We evaluated 21 patients with biochemical relapse after EBRT. Patients underwent 18F-Choline-PET/contrast-enhanced (Ce)CT, 18F-Fluoride-PET/CT, and mMRI. Imaging coregistration of PET and mMRI was performed. Results. 18F-Choline-PET/MRI was positive in 18/21 patients, with a detection rate (DR) of 86%. DRs of 18F-Choline-PET/CT, CeCT, and mMRI were 76%, 43%, and 81%, respectively. In terms of DR the only significant difference was between 18F-Choline-PET/MRI and CeCT. On lesion-based analysis, the accuracy of 18F-Choline-PET/MRI, 18F-Choline-PET/CT, CeCT, and mMRI was 99%, 95%, 70%, and 85%, respectively. Accuracy, sensitivity, and NPV of 18F-Choline-PET/MRI were significantly higher than those of both mMRI and CeCT. On whole-body assessment of bone metastases, the sensitivity of 18F-Choline-PET/CT and 18F-Fluoride-PET/CT was significantly higher than that of CeCT. Regarding local and lymph node relapse, we found a significant inverse correlation between ADC and SUV-max. Conclusion. 18F-Choline-PET/MRI is a promising technique in detecting PC relapse. PMID:24877053

  9. Decadal Air-Sea Interaction in the North Atlantic Based on Observations and Modeling Results

    NASA Technical Reports Server (NTRS)

    Hakkinen, Sirpa

    1998-01-01

    The decadal, 12-14 year, cycle observed in the North Atlantic SST and tide gauge data was examined using the NCEP/NCAR reanalyses, COADS data and an ocean model simulation. Besides this decadal mode, a shorter, subdecadal period of about 8 years exists in tide gauge data north of 40N, in the subpolar SST and in the winter North Atlantic Oscillation (NAO) index and in subpolar winter heat flux values. The decadal cycle is a well separated mode in a singular spectrum analysis (SSA) for a time series of SST EOF mode 1 with a center over the Gulf Stream extension. Tide gauge and SST data are consistent in that both show a significant subdecadal periodicity exclusively in the subpolar gyre, but in subtropics the 12-14 year period is the prominent, but nonstationary, decadal signal. The main finding of this study is that this 12-14 year cycle can be constructed based on the leading mode of the surface heat flux. This connection to the surface heat flux implicates the participation of the thermohaline circulation in the decadal cycle. During the cycle starting from the positive index phase of NAO, SST and oceanic heat content anomalies are created in subtropics due to local heat flux and intensification of the thermohaline circulation. The anomalies advect to the subpolar gyre where they are amplified by local heat flux and are part of the negative feedback of thermohaline circulation on itself. Consequently the oceanic thermohaline circulation slows down and the opposite cycle starts. The oscillatory nature would not be possible without the active atmospheric participation in the cycle, because it provides the unstable interaction through heat flux, without it, the oceanic mode would be damped. This analysis suggests that the two principal modes of heat flux variability, corresponding to patterns similar to North Atlantic Oscillation (NAO) and Western Atlantic (WA), are part of the same decadal cycle and an indirect measure of the north-south movement of the storm tracks.

  10. Global ozone observations from the UARS MLS: An overview of zonal-mean results

    SciTech Connect

    Froidevaux, L.; Waters, J.W.; Read, W.G.; Elson, L.S.; Flower, D.A.; Jarnot, R.F.

    1994-10-15

    Global ozone observations from the Microwave Limb Sounder (MLS) aboard the Upper Atmosphere Research Satellite (UARS) are presented, in both vertically resolved and column abundance formats. The authors review the zonal-mean ozone variations measured over the two and a half years since launch in September 1991. Well-known features such as the annual and semiannual variations are ubiquitous. In the equatorial regions, longer-term changes are believed to be related to the quasi-biennial oscillation (QBO), with a strong semiannual signal above 20 hPa. Ozone values near 50 hPa exhibit an equatorial low from October 1991 to June 1992, after which the low ozone pattern splits into two subtropical lows (possibly in connection with residual circulation changes tied to the QBO) and returns to an equatorial low in September 1993. The ozone hole development at high southern latitudes is apparent in MLS column data integrated down to 100 hPa, with a pattern generally consistent with Nimbus-7 Total Ozone Mapping Spectrometer (TOMS) measurements of total column; the MLS data reinforce current knowledge of this lower-stratospheric phenomenon by providing a height-dependent view of the variations. The region from 30{degrees}S to 30{degrees}N (an area equal to half the global area) shows very little change in the ozone column from year to year and within each year. Finally, residual ozone values extracted from TOMS-minus-MLS column data are briefly presented as a preliminary view into the potential usefulness of such studies, with information on tropospheric ozone as an ultimate goal. 99 refs., 13 figs.

  11. Observables sensitive to absolute neutrino masses: A reappraisal after WMAP 3-year and first MINOS results

    SciTech Connect

    Fogli, G. L.; Lisi, E.; Marrone, A.; Melchiorri, A.; Serra, P.; Palazzo, A.; Silk, J.; Slosar, A.

    2007-03-01

    In the light of recent neutrino oscillation and nonoscillation data, we revisit the phenomenological constraints applicable to three observables sensitive to absolute neutrino masses: The effective neutrino mass in single 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}). In particular, we include the constraints coming from the first Main Injector Neutrino Oscillation Search (MINOS) data and from the Wilkinson Microwave Anisotropy Probe (WMAP) three-year (3y) data, as well as other relevant cosmological data and priors. We find that the largest neutrino squared mass difference is determined with a 15% accuracy (at 2{sigma}) after adding MINOS to world data. We also find upper bounds on the sum of neutrino masses {sigma} ranging from {approx}2 eV (WMAP-3y data only) to {approx}0.2 eV (all cosmological data) at 2{sigma}, in agreement with previous studies. In addition, we discuss the connection of such bounds with those placed on the matter power spectrum normalization parameter {sigma}{sub 8}. We show how the partial degeneracy between {sigma} and {sigma}{sub 8} in WMAP-3y data is broken by adding further cosmological data, and how the overall preference of such data for relatively high values of {sigma}{sub 8} pushes the upper bound of {sigma} in the sub-eV range. Finally, for various combination of data sets, we revisit the (in)compatibility between current {sigma} and m{sub {beta}}{sub {beta}} constraints (and claims), and derive quantitative predictions for future single and double beta decay experiments.

  12. SEVEN-YEAR WILKINSON MICROWAVE ANISOTROPY PROBE (WMAP ) OBSERVATIONS: SKY MAPS, SYSTEMATIC ERRORS, AND BASIC RESULTS

    SciTech Connect

    Jarosik, N.; Page, L.; Bennett, C. L.; Gold, B.; Larson, D.; Dunkley, J.; Greason, M. R.; Hill, R. S.; Odegard, N.; Weiland, J. L.; Halpern, M.; Hinshaw, G.; Kogut, A.; Limon, M.; Meyer, S. S.; Nolta, M. R.; Smith, K. M.; Spergel, D. N.; Tucker, G. S.

    2011-02-01

    New full-sky temperature and polarization maps based on seven years of data from WMAP are presented. The new results are consistent with previous results, but have improved due to reduced noise from the additional integration time, improved knowledge of the instrument performance, and improved data analysis procedures. The improvements are described in detail. The seven-year data set is well fit by a minimal six-parameter flat {Lambda}CDM model. The parameters for this model, using the WMAP data in conjunction with baryon acoustic oscillation data from the Sloan Digital Sky Survey and priors on H{sub 0} from Hubble Space Telescope observations, are {Omega}{sub b} h {sup 2} = 0.02260 {+-} 0.00053, {Omega}{sub c} h {sup 2} = 0.1123 {+-} 0.0035, {Omega}{sub {Lambda}} = 0.728{sup +0.015}{sub -0.016}, n{sub s} = 0.963 {+-} 0.012, {tau} = 0.087 {+-} 0.014, and {sigma}{sub 8} = 0.809 {+-} 0.024 (68% CL uncertainties). The temperature power spectrum signal-to-noise ratio per multipole is greater that unity for multipoles l {approx}< 919, allowing a robust measurement of the third acoustic peak. This measurement results in improved constraints on the matter density, {Omega}{sub m} h {sup 2} = 0.1334{sup +0.0056}{sub -0.0055}, and the epoch of matter-radiation equality, z{sub eq} = 3196{sup +134}{sub -133}, using WMAP data alone. The new WMAP data, when combined with smaller angular scale microwave background anisotropy data, result in a 3{sigma} detection of the abundance of primordial helium, Y{sub He} = 0.326 {+-} 0.075. When combined with additional external data sets, the WMAP data also yield better determinations of the total mass of neutrinos, {Sigma}M{sub {nu}} {<=} 0.58 eV(95%CL), and the effective number of neutrino species, N{sub eff} = 4.34{sup +0.86}{sub -0.88}. The power-law index of the primordial power spectrum is now determined to be n{sub s} = 0.963 {+-} 0.012, excluding the Harrison-Zel'dovich-Peebles spectrum by >3{sigma}. These new WMAP measurements provide important tests of big bang cosmology.

  13. The results of the 2015 campaign of observation of mutual events of the Jovian satellites

    NASA Astrophysics Data System (ADS)

    Arlot, J. E.; Saquet, E.; Emelianov, N.

    2015-10-01

    From September 2014 to June 2015 mutual events of the Galilean satellites occurred around the Jovian equinox occurring on February 6, 2015. The observations of these events provide very accurate information on the relative astrometry of the satellites. Previous campaign of observations have shown the high interest of such observations now performed mainly by amateur astronomers: the Galilean satellites are bright and the magnitude drop during these events is easily observable. The 2014- 2015 campaign is especially favorable because of the maximum of events which will occur during the opposition between the Sun and Jupiter. More, eclipses of Thebe and Amalthea by the Galileans have been observed. Note that the positive declination of Jupiter made the observations easier in the Northern hemisphere where, unfortunately, the meteorological conditions were bad.

  14. Magnesium intake, bone mineral density, and fractures: results from the Women's Health Initiative Observational Study1234

    PubMed Central

    Orchard, Tonya S; Larson, Joseph C; Alghothani, Nora; Bout-Tabaku, Sharon; Cauley, Jane A; Chen, Zhao; LaCroix, Andrea Z; Wactawski-Wende, Jean; Jackson, Rebecca D

    2014-01-01

    Background: Magnesium is a necessary component of bone, but its relation to osteoporotic fractures is unclear. Objective: We examined magnesium intake as a risk factor for osteoporotic fractures and altered bone mineral density (BMD). Design: This prospective cohort study included 73,684 postmenopausal women enrolled in the Women's Health Initiative Observational Study. Total daily magnesium intake was estimated from baseline food-frequency questionnaires plus supplements. Hip fractures were confirmed by a medical record review; other fractures were identified by self-report. A baseline BMD analysis was performed in 4778 participants. Results: Baseline hip BMD was 3% higher (P < 0.001), and whole-body BMD was 2% higher (P < 0.001), in women who consumed >422.5 compared with <206.5 mg Mg/d. However, the incidence and RR of hip and total fractures did not differ across quintiles of magnesium. In contrast, risk of lower-arm or wrist fractures increased with higher magnesium intake [multivariate-adjusted HRs of 1.15 (95% CI: 1.01, 1.32) and 1.23 (95% CI: 1.07, 1.42) for quintiles 4 and 5, respectively, compared with quintile 1; P-trend = 0.002]. In addition, women with the highest magnesium intakes were more physically active and at increased risk of falls [HR for quintile 4: 1.11 (95% CI: 1.06, 1.16); HR for quintile 5: 1.15 (95% CI: 1.10, 1.20); P-trend < 0.001]. Conclusions: Lower magnesium intake is associated with lower BMD of the hip and whole body, but this result does not translate into increased risk of fractures. A magnesium consumption slightly greater than the Recommended Dietary Allowance is associated with increased lower-arm and wrist fractures that are possibly related to more physical activity and falls. This trial was registered at clinicaltrials.gov as NCT00000611. PMID:24500155

  15. Titan: Preliminary results on surface properties and photometry from VIMS observations of the early flybys

    USGS Publications Warehouse

    Buratti, B.J.; Sotin, C.; Brown, R.H.; Hicks, M.D.; Clark, R.N.; Mosher, J.A.; McCord, T.B.; Jaumann, R.; Baines, K.H.; Nicholson, P.D.; Momary, T.; Simonelli, D.P.; Sicardy, B.

    2006-01-01

    Cassini observations of the surface of Titan offer unprecedented views of its surface through atmospheric windows in the 1-5 ??m region. Images obtained in windows for which the haze opacity is low can be used to derive quantitative photometric parameters such as albedo and albedo distribution, and physical properties such as roughness and particle characteristics. Images from the early Titan flybys, particularly T0, Ta, and T5 have been analyzed to create albedo maps in the 2.01 and 2.73 ??m windows. We find the average normal reflectance at these two wavelengths to be 0.15??0.02 and 0.035??0.003, respectively. Titan's surface is bifurcated into two albedo regimes, particularly at 2.01 ??m. Analysis of these two regimes to understand the physical character of the surface was accomplished with a macroscopic roughness model. We find that the two types of surface have substantially different roughness, with the low-albedo surface exhibiting mean slope angles of ???18??, and the high-albedo terrain having a much more substantial roughness with a mean slope angle of ???34??. A single-scattering phase function approximated by a one-term Henyey-Greenstein equation was also fit to each unit. Titan's surface is back-scattering (g???0.3-0.4), and does not exhibit substantially different backscattering behavior between the two terrains. Our results suggest that two distinct geophysical domains exist on Titan: a bright region cut by deep drainage channels and a relatively smooth surface. The two terrains are covered by a film or a coating of particles perhaps precipitated from the satellite's haze layer and transported by eolian processes. Our results are preliminary: more accurate values for the surface albedo and physical parameters will be derived as more data is gathered by the Cassini spacecraft and as a more complete radiative transfer model is developed from both Cassini orbiter and Huygens Lander measurements. ?? 2006 Elsevier Ltd. All rights reserved.

  16. Clinical course and prognosis in ulcerative colitis: results from population-based and observational studies

    PubMed Central

    Monstad, Iril; Hovde, istein; Solberg, Inger Camilla; A. Moum, Bjrn

    2014-01-01

    The clinical course of ulcerative colitis (UC) may range from a quiescent course with prolonged periods of remission to fulminant disease requiring intensive medical treatment or surgery. Disease outcome is often determined by relapse rates, the development of colorectal cancer (CRC) and mortality rates. Early patient classification, identifying those with a high risk of developing complicated disease, is essential for choosing appropriate treatment. This paper reviews the clinical outcomes of UC patients as reported in population-based and observational studies representative of the whole patient population. Extensive colitis, a high level of systemic symptoms and young age at diagnosis are factors associated with a high risk of colectomy. Patients with distal disease who progress to extensive colitis seem to be a subgroup with an especially high risk of colectomy. Some prognostic factors of severe disease have been identified which could be used to optimize treatment and possibly reduce future complications. The overall risk of CRC and mortality was not significantly different from that of the background population. These results may have implications for follow-up strategies, especially regarding endoscopic surveillance of UC patients. PMID:24733679

  17. MICROWAVE OBSERVATIONS OF EDGE-ON PROTOPLANETARY DISKS: PROGRAM OVERVIEW AND FIRST RESULTS

    SciTech Connect

    Melis, Carl; Duchene, G.; Chomiuk, Laura; Palmer, Patrick; Perrin, M. D.; Maddison, S. T.; Menard, F.; Pinte, C.; Duvert, G.

    2011-09-20

    We are undertaking a multi-frequency Expanded Very Large Array (EVLA) survey of edge-on protoplanetary disks to probe the growth of solids in each disk, sedimentation of such material into the disk midplane, and the connection of these phenomena to the planet formation process. The projection of edge-on disk systems along our line of sight enables a study of the vertical stratification of large grains with fewer model dependencies than would be required for disks that are more face-on. Robust studies of the spatial distribution of grains up to {approx}1 cm in size are possible with the wavelength range and sensitivity of the EVLA. In this contribution, we describe target selection and observational strategies. First results concerning the Class 0 source IRAS 04368+2557 (L1527 IRS) are presented, including a study of this source's 8.46 GHz continuum variability over short and long time baselines and an indication that its protoplanetary disk may have a dearth of pebble-sized grains.

  18. New results near {sup 100}Sn : observation of single-neutron states in {sup 101}Sn.

    SciTech Connect

    Seweryniak, D.; Carpenter, M. P.; Gros, S.; Hecht, A. A.; Hoteling, N.; Janssens, R. V. F.; Khoo, T. L.; Lauritsen, T.; Lister, C. J.; Lotay, G.; Peterson, D.; Robinson, A. P.; Walters, W. B.; Wang, X.; Woods, P. J.; Zhu, S.; Physics; Univ. of Maryland; Univ. of Edinburgh; Univ. of Notre Dame

    2009-03-01

    A search for in-beam {gamma}-ray transitions in {sup 101}Sn, which contains only one neutron outside the {sup 100}Sn core, using a novel approach was carried out at the Argonne Tandem-Linac System. {sup 101}Sn nuclei were produced using the {sup 46}Ti({sup 58}Ni, 3n){sup 101}Sn fusion-evaporation reaction. Beta-delayed protons with energies and decay times consistent with previous {sup 101}Sn decay studies were observed at the focal plane of the Fragment Mass Analyzer. In-beam {gamma} rays were detected in the Gammasphere Ge-detector array and were correlated with the {sup 101}Sn {beta}-delayed protons using the Recoil-Decay Tagging method. As a result, a {gamma}-ray transition between the single-neutron {nu}g{sub 7/2} and {nu}d{sub 5/2} states situated at the Fermi surface was identified. The measured {nu}g{sub 7/2}-{nu}d{sub 5/2} energy splitting was compared with predictions corresponding to various mean-field potentials and was used to calculate multi-neutron configurations in light Sn isotopes. Similar approach can be used to study core excitations in {sup 101}Sn and other exotic nuclei near {sup 100}Sn.

  19. First Results from NuSTAR observations of Galactic Center Non-thermal Filaments

    NASA Astrophysics Data System (ADS)

    Hailey, Charles J.; Nynka, M.; Zhang, S.; Mori, K.; NuSTAR Team

    2014-01-01

    The Galactic Center is a complex and crowded region that contains many filamentary structures. While these non-thermal objects have been well-studied in various energy bands, their exact natures are still unknown. Some, such as the Chandra object G359.97-0.038, have been theorized to be pulsar wind nebula (PWN) candidates based on their soft X-ray morphology (Johnson et al. 2009). Others, most notably the Sgr A-E knot, have been attributed to either PWN candidates (Lu et al. 2003) or supernova remnant (SNR) shock fronts interacting with molecular clouds (Yusef-Zadeh et al. 2005). NuSTAR observations of the Galactic Center beginning October 2012 have unambiguously detected several X-ray bright non-thermal objects that have Chandra counterparts. Here we present NuSTAR analysis of these sources. We discuss the spectral and morphological results in the high-energy X-ray band and the subsequent implications on the natures of these structures.

  20. Coronae at 3 Gyr: First Results from a Chandra Observation of the Open Cluster Ruprecht 147

    NASA Astrophysics Data System (ADS)

    Saar, Steven H.; Curtis, Jason L.; Wright, Jason

    2014-06-01

    Ruprecht 147 is the oldest nearby star cluster, with an age of 3 Gyr and a distance of 300 pc. This makes it an important benchmark in exploring activity-age-rotation relationships, bridging the gap between the Hyades and M67. We present the first results from a deep 250 ksec ACIS-I observation of the cluster. Analysis of the longest (81 ksec) pointing detects more than half of the known members in the field, with spectral types ranging from F6 to K5. The star most like the Sun in our sample, a G2V, has an X-ray luminosity (0.2-7 keV) of L_X ~ 1.1e28 ergs/s, which suggests a scaling with age t of log L_X ~ -b log t where 1.25 < b < 4, possibly steeper than seen at younger ages. This research was supported by Chandra grant G02-13022X.

  1. Dynamic Interactions between Contrast Agent Microbubbles: High Speed Camera Observations and Simulation Results

    NASA Astrophysics Data System (ADS)

    Stride, Eleanor; Chetty, Kevin; Eckersley, Robert

    2007-05-01

    The efficacy of coated microbubbles as contrast agents for ultrasound imaging has been well established over the past two decades. More recently, their use as carriers for targeted drug delivery has also become an active area of research. However, the behaviour of microbubbles in an ultrasound field is by no means fully understood. For example, the dynamic interactions between microbubbles have frequently been neglected when considering contrast agent suspensions. In this investigation, high speed camera observations of a commercial contrast agent (SonoVue) were made under controlled and calibrated acoustic exposure conditions (single 4 cycle (FWHM) Gaussian pulse with 0.5 MHz centre frequency and peak negative pressure <100 kPa). These were compared with numerical simulations of both single and pairs of coated microbubbles corresponding to the experiments. Both the theoretical and experimental results indicate that the dynamic behaviour of a microbubble may be substantially affected by the presence of neighbouring bubbles under certain conditions. This, in turn, may affect the microbubble's acoustic response and its destruction threshold, which has potentially significant implications for both diagnostic and therapeutic applications.

  2. Nine-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Final Maps and Results

    NASA Technical Reports Server (NTRS)

    Bennett, C. L.; Larson, D.; Weiland, J. L.; Jaorsik, N.; Hinshaw, G.; Odegard, N.; Smith, K. M.; Hill, R. S.; Gold, B.; Halpern, M; Komatsu, E.; Nolta, M. R.; Page, L.; Spergel, D. N.; Wollack, E.; Dunkley, J.; Kogut, A.; Limon,, M.; Meyer, S. S.; Tucker, G. S.; Wright, E. L.

    2013-01-01

    We present the final nine-year maps and basic results from the Wilkinson Microwave Anisotropy Probe (WMAP) mission. The full nine-year analysis of the time-ordered data provides updated characterizations and calibrations of the experiment. We also provide new nine-year full sky temperature maps that were processed to reduce the asymmetry of the effective beams. Temperature and polarization sky maps are examined to separate cosmic microwave background (CMB) anisotropy from foreground emission, and both types of signals are analyzed in detail.We provide new point source catalogs as well as new diffuse and point source foreground masks. An updated template-removal process is used for cosmological analysis; new foreground fits are performed, and new foreground reduced are presented.We nowimplement an optimal C(exp -1)1 weighting to compute the temperature angular power spectrum. The WMAP mission has resulted in a highly constrained Lambda-CDM cosmological model with precise and accurate parameters in agreement with a host of other cosmological measurements. When WMAP data are combined with finer scale CMB, baryon acoustic oscillation, and Hubble constant measurements, we find that big bang nucleosynthesis is well supported and there is no compelling evidence for a non-standard number of neutrino species (N(sub eff) = 3.84 +/- 0.40). The model fit also implies that the age of the universe is (sub 0) = 13.772 +/- 0.059 Gyr, and the fit Hubble constant is H(sub 0) = 69.32 +/- 0.80 km/s/ Mpc. Inflation is also supported: the fluctuations are adiabatic, with Gaussian random phases; the detection of a deviation of the scalar spectral index from unity, reported earlier by the WMAP team, now has high statistical significance (n(sub s) = 0.9608+/-0.0080); and the universe is close to flat/Euclidean (Omega = -0.0027+0.0039/-0.0038). Overall, the WMAP mission has resulted in a reduction of the cosmological parameter volume by a factor of 68,000 for the standard six-parameter ?Lambda-CDM model, based on CMB data alone. For a model including tensors, the allowed seven-parameter volume has been reduced by a factor 117,000. Other cosmological observations are in accord with the CMB predictions, and the combined data reduces the cosmological parameter volume even further.With no significant anomalies and an adequate goodness of fit, the inflationary flat Lambda-CDM model and its precise and accurate parameters rooted in WMAP data stands as the standard model of cosmology.

  3. NINE-YEAR WILKINSON MICROWAVE ANISOTROPY PROBE (WMAP) OBSERVATIONS: FINAL MAPS AND RESULTS

    SciTech Connect

    Bennett, C. L.; Larson, D.; Weiland, J. L.; Jarosik, N.; Page, L.; Hinshaw, G.; Halpern, M.; Odegard, N.; Hill, R. S.; Smith, K. M.; Gold, B.; Komatsu, E.; Nolta, M. R.; Spergel, D. N.; Wollack, E.; Kogut, A.; Limon, M.; Meyer, S. S.; Tucker, G. S.; and others

    2013-10-01

    We present the final nine-year maps and basic results from the Wilkinson Microwave Anisotropy Probe (WMAP) mission. The full nine-year analysis of the time-ordered data provides updated characterizations and calibrations of the experiment. We also provide new nine-year full sky temperature maps that were processed to reduce the asymmetry of the effective beams. Temperature and polarization sky maps are examined to separate cosmic microwave background (CMB) anisotropy from foreground emission, and both types of signals are analyzed in detail. We provide new point source catalogs as well as new diffuse and point source foreground masks. An updated template-removal process is used for cosmological analysis; new foreground fits are performed, and new foreground-reduced CMB maps are presented. We now implement an optimal C {sup –1} weighting to compute the temperature angular power spectrum. The WMAP mission has resulted in a highly constrained ΛCDM cosmological model with precise and accurate parameters in agreement with a host of other cosmological measurements. When WMAP data are combined with finer scale CMB, baryon acoustic oscillation, and Hubble constant measurements, we find that big bang nucleosynthesis is well supported and there is no compelling evidence for a non-standard number of neutrino species (N {sub eff} = 3.84 ± 0.40). The model fit also implies that the age of the universe is t {sub 0} = 13.772 ± 0.059 Gyr, and the fit Hubble constant is H {sub 0} = 69.32 ± 0.80 km s{sup –1} Mpc{sup –1}. Inflation is also supported: the fluctuations are adiabatic, with Gaussian random phases; the detection of a deviation of the scalar spectral index from unity, reported earlier by the WMAP team, now has high statistical significance (n{sub s} = 0.9608 ± 0.0080); and the universe is close to flat/Euclidean (Ω{sub k} = -0.0027{sup +0.0039}{sub -0.0038}). Overall, the WMAP mission has resulted in a reduction of the cosmological parameter volume by a factor of 68,000 for the standard six-parameter ΛCDM model, based on CMB data alone. For a model including tensors, the allowed seven-parameter volume has been reduced by a factor 117,000. Other cosmological observations are in accord with the CMB predictions, and the combined data reduces the cosmological parameter volume even further. With no significant anomalies and an adequate goodness of fit, the inflationary flat ΛCDM model and its precise and accurate parameters rooted in WMAP data stands as the standard model of cosmology.

  4. Thermospheric and geomagnetic responses to interplanetary coronal mass ejections observed by ACE and GRACE: Statistical results

    NASA Astrophysics Data System (ADS)

    Krauss, S.; Temmer, M.; Veronig, A.; Baur, O.; Lammer, H.

    2015-10-01

    For the period July 2003 to August 2010, the interplanetary coronal mass ejection (ICME) catalogue maintained by Richardson and Cane lists 106 Earth-directed events, which have been measured in situ by plasma and field instruments on board the ACE satellite. We present a statistical investigation of the Earth's thermospheric neutral density response by means of accelerometer measurements collected by the Gravity Recovery And Climate Experiment (GRACE) satellites, which are available for 104 ICMEs in the data set, and its relation to various geomagnetic indices and characteristic ICME parameters such as the impact speed (vmax), southward magnetic field strength (Bz). The majority of ICMEs causes a distinct density enhancement in the thermosphere, with up to a factor of 8 compared to the preevent level. We find high correlations between ICME Bz and thermospheric density enhancements (≈0.9), while the correlation with the ICME impact speed is somewhat smaller (≈0.7). The geomagnetic indices revealing the highest correlations are Dst and SYM-H(≈0.9); the lowest correlations are obtained for Kp and AE (≈0.7), which show a nonlinear relation with the thermospheric density enhancements. Separating the response for the shock-sheath region and the magnetic structure of the ICME, we find that the Dst and SYM-H reveal a tighter relation to the Bz minimum in the magnetic structure of the ICME, whereas the polar cap indices show higher correlations with the Bz minimum in the shock-sheath region. Since the strength of the Bz component—either in the sheath or in the magnetic structure of the ICME—is highly correlated (≈0.9) with the neutral density enhancement, we discuss the possibility of satellite orbital decay estimates based on magnetic field measurements at L1, i.e., before the ICME hits the Earth magnetosphere. These results are expected to further stimulate progress in space weather understanding and applications regarding satellite operations.

  5. Using Qualitative Observation To Document Group Processes in Accelerated Schools Training: Techniques and Results.

    ERIC Educational Resources Information Center

    McFarland, Katherine; Batten, Constance

    This paper describes the use of qualitative observation techniques for gathering and analyzing data related to group processes during an Accelerated Schools Model training session. The purposes for this research were to observe the training process in order better to facilitate present continuation and future training, to develop questions for…

  6. Fusing Observations and Model Results for Creation of Enhanced Ozone Spatial Fields: Comparison of Three Techniques

    EPA Science Inventory

    This paper presents three simple techniques for fusing observations and numerical model predictions. The techniques rely on model/observation bias being considered either as error free, or containing some uncertainty, the latter mitigated with a Kalman filter approach or a spati...

  7. Investigation of Ionospheric Disturbances Using Radio and Optical Observations in South-East Asia -- The Initial Results of the ASI and FPI Observations in Chiang Mai, Thailand

    NASA Astrophysics Data System (ADS)

    Kubota, M.; Nagatsuma, T.; Otsuka, Y.; Shiokawa, K.; Komonjinda, S.; Komolmis, T.; Somboon, E.; Tsugawa, T.; Maruyama, T.; Murata, K. T.

    2010-12-01

    For the purpose of monitoring and forecasting equatorial ionospheric disturbances, SEALION (SouthEast Asia Low-latitude IOnospheric Network) has been developed since 2003 as a cooperation project by National Institute of Information and Communications Technology (NICT), King Mongkut's Institute of Technology Ladkrabang (KMITL) in Thailand, Chiang Mai University (CMU) in Thailand, National Institute of Aeronautics and Space (LAPAN) in Indonesia, Hanoi Institute of Geophysics (HIG), Vietnamese Academy of Science and Technology in Vietnam, Center for Space Science and Applied Research (CSSAR), Chinese Academy of Sciences in China, Kyoto University in Japan, and Solar-Terrestrial Environment Laboratory (STEL), Nagoya University in Japan. SEALION consists of five ionosondes, four GPS receivers, two GPS scintillation monitors, and a magnetometer. As a part of this project, we newly installed an all-sky imager (ASI) and a Fabry-Perot Interferometer (FPI) at Sirindhorn observatory in Chiang Mai (18.8N, 98.9E, Dip lat. 13.1), Thailand. This site is located near conjugate to EAR site in Kototabang, Indonesia. One of main targets of the ASI observation is the large-scale wave structure (LSWS) with wavelengths of 100-1000 km. The LSWS is thought to be connected to the generation mechanism of equatorial plasma bubbles (EPB). The optical observations in Chiang Mai started in February 2010, and we have detected several ionospheric disturbance events with these instruments In this paper, we will show the initial results of the optical observations from Sirindhorn observatory, and discuss the features of ionospheric disturbances in Southeast Asia.

  8. Preliminary results of astrometric ccd observations of exstragalactic sources with the AZT-8 reflector of the Kharkiv Observatory

    NASA Astrophysics Data System (ADS)

    Fedorov, P. N.; Velichko, F. P.; Filonenko, V. S.

    2000-12-01

    First results of astrometric CCD observations and processing of optical counterparts of the ERS extragalactic radio sources are presented. Characteristics of the accuracy of observations in the chip frame of reference as a function of stellar magnitude are given.

  9. Initial results from NuSTAR observations of the Norma Arm

    SciTech Connect

    Bodaghee, Arash; Tomsick, John A.; Krivonos, Roman; Barrière, Nicolas; Boggs, Steven E.; Craig, William W.; Stern, Daniel; Bauer, Franz E.; Fornasini, Francesca M.; Christensen, Finn E.; Gotthelf, Eric V.; Hailey, Charles J.; Mori, Kaya; Harrison, Fiona A.; Hong, Jaesub; Zhang, William W.

    2014-08-10

    Results are presented for an initial survey of the Norma Arm gathered with the focusing hard X-Ray Telescope NuSTAR. The survey covers 0.2 deg{sup 2} of sky area in the 3-79 keV range with a minimum and maximum raw depth of 15 ks and 135 ks, respectively. Besides a bright black-hole X-ray binary in outburst (4U 1630–47) and a new X-ray transient (NuSTAR J163433–473841), NuSTAR locates three sources from the Chandra survey of this region whose spectra are extended above 10 keV for the first time: CXOU J163329.5–473332, CXOU J163350.9–474638, and CXOU J163355.1–473804. Imaging, timing, and spectral data from a broad X-ray range (0.3-79 keV) are analyzed and interpreted with the aim of classifying these objects. CXOU J163329.5–473332 is either a cataclysmic variable or a faint low-mass X-ray binary. CXOU J163350.9–474638 varies in intensity on year-long timescales, and with no multi-wavelength counterpart, it could be a distant X-ray binary or possibly a magnetar. CXOU J163355.1–473804 features a helium-like iron line at 6.7 keV and is classified as a nearby cataclysmic variable. Additional surveys are planned for the Norma Arm and Galactic Center, and those NuSTAR observations will benefit from the lessons learned during this pilot study.

  10. Initial Results from NuSTAR Observations of the NORMA ARM

    NASA Technical Reports Server (NTRS)

    Bodaghee, Arash; Tomsick, John A.; Krivonos, Roman; Stern, Daniel; Bauer, Franz E.; Fornasini, Francesca M.; Barriere, Nicolas; Boggs, Steven E.; Christensen, Finn E.; Zhang, William W.

    2014-01-01

    Results are presented for an initial survey of the Norma Arm gathered with the focusing hard X-Ray Telescope NuSTAR. The survey covers 0.2 sq deg of sky area in the 3-79 keV range with a minimum and maximum raw depth of 15 ks and 135 ks, respectively. Besides a bright black-hole X-ray binary in outburst (4U 1630-47) and a new X-ray transient (NuSTAR J163433-473841), NuSTAR locates three sources from the Chandra survey of this region whose spectra are extended above 10 keV for the first time: CXOU J163329.5-473332, CXOU J163350.9-474638, and CXOU J163355.1-473804. Imaging, timing, and spectral data from a broad X-ray range (0.3-79 keV) are analyzed and interpreted with the aim of classifying these objects. CXOU J163329.5-473332 is either a cataclysmic variable or a faint low-mass X-ray binary. CXOU J163350.9-474638 varies in intensity on year-long timescales, and with no multi-wavelength counterpart, it could be a distant X-ray binary or possibly a magnetar. CXOU J163355.1-473804 features a helium-like iron line at 6.7 keV and is classified as a nearby cataclysmic variable. Additional surveys are planned for the Norma Arm and Galactic Center, and those NuSTAR observations will benefit from the lessons learned during this pilot study.

  11. The brightest TGF ever observed? - New results from the RHESSI satellite

    NASA Astrophysics Data System (ADS)

    Kelley, Nicole; Smith, David; Dwyer, Joseph; Splitt, Michael; Holzworth, Robert; Buzbee, Paul; Infanger, Alex; Lazarus, Steve

    2015-04-01

    Terrestrial gamma-ray flashes (TGFs) are sub-millisecond bursts of gamma rays originating from thunderstorms. They were first discovered in 1994 by the BATSE instrument aboard the Compton Gamma-ray Observatory (CGRO). Since their discovery, thousands of TGFs have been detected by other gamma-ray satellites. A new class of super-bright terrestrial gamma-ray flashes has been found in the data from the Reuven-Ramaty High Energy Solar Spectroscopic Imager (RHESSI). These events are so bright that they cause the RHESSI instrumentation to become paralyzed during the peak of the TGF. While the instrument is paralyzed, all information about the TGF is lost. A new modeling method using the Compton tail of these TGFs is used to find their brightness. These events are modeled by using the relativistic feedback model and then propagating the gamma rays through the atmosphere and then through RHESSI. The TGFs are placed at different altitudes and distances from the spacecraft. Three TGFs were modeled using this method, one of which may be the brightest TGF ever observed. The range of possible luminosities for this event will be shown. For the other two events, a World Wide Lightning Location Network (WWLLN) lightning sferic match has been found so the distance from RHESSI is known. Using infrared (IR) data, the cloud top height can be estimated which, in the context of current in-cloud TGF models, places an upper limit on the altitude of the TGF. The brightness for these events, where the distance and altitude is known, will be reported. The benefits and limitations of this novel approach of using the Compton tails of TGFs will be discussed. Notably, the results obtained for the TGF luminosity at the source are nearly independent of the (unknown) original angular distribution of the bremsstrahlung radiation.

  12. Thermodynamic Spectrum of Solar Flares Based on SDO/EVE Observations: Techniques and First Results

    NASA Astrophysics Data System (ADS)

    Wang, Yuming; Zhou, Zhenjun; Zhang, Jie; Liu, Kai; Liu, Rui; Shen, Chenglong; Chamberlin, Phillip C.

    2016-03-01

    The Solar Dynamics Observatory (SDO)/EUV Variability Experiment (EVE) provides rich information on the thermodynamic processes of solar activities, particularly on solar flares. Here, we develop a method to construct thermodynamic spectrum (TDS) charts based on the EVE spectral lines. This tool could potentially be useful for extreme ultraviolet (EUV) astronomy to learn about the eruptive activities on distant astronomical objects. Through several cases, we illustrate what we can learn from the TDS charts. Furthermore, we apply the TDS method to 74 flares equal to or greater than the M5.0 class, and reach the following statistical results. First, EUV peaks are always behind the soft X-ray (SXR) peaks and stronger flares tend to have faster cooling rates. There is a power-law correlation between the peak delay times and the cooling rates, suggesting a coherent cooling process of flares from SXR to EUV emissions. Second, there are two distinct temperature drift patterns, called Type I and Type II. For Type I flares, the enhanced emission drifts from high to low temperature like a quadrilateral, whereas for Type II flares the drift pattern looks like a triangle. Statistical analysis suggests that Type II flares are more impulsive than Type I flares. Third, for late-phase flares, the peak intensity ratio of the late phase to the main phase is roughly correlated with the flare class, and the flares with a strong late phase are all confined. We believe that the re-deposition of the energy carried by a flux rope, which unsuccessfully erupts out, into thermal emissions is responsible for the strong late phase found in a confined flare. Furthermore, we show the signatures of the flare thermodynamic process in the chromosphere and transition region in the TDS charts. These results provide new clues to advance our understanding of the thermodynamic processes of solar flares and associated solar eruptions, e.g., coronal mass ejections.

  13. Preliminary observation result of urban boundary layer at Taipei 101 Skyscraper

    NASA Astrophysics Data System (ADS)

    Lin, P. H.; Mei, K. C.; Chen, Y. C.

    2012-04-01

    Taipei 101 Skyscraper (508 m), the secondary tallest commercial building around the world, is the metropolis landmark of Taipei, Taiwan. The minute-resolution of wind field, air temperature and humidity sampled at the northeastern corner of 34th (151 m) and 82th (353 m) balconies are collected from January of 2011 until now for studying urban meteorological boundary layer. 31 sets of balloon-borne radiosondes near Taipei 101 Skyscraper were launched for comparison. Meanwhile, a CFD model (STREAM) was used to simulate the wind flow surrounding 101 Skyscraper. As expected, the measured wind field could be distorted strongly by the building. Comparing with radiosonde data, the wind direction measured at Taipei 101 skyscraper has 70~90 degrees clockwise turn (SN) under the prevailing northeastern (NE) wind flow. The measured wind speed at 101 Skyscraper also has ~50% reduction compared to radiosonde measurement, and the ratio of speed reduction from different wind directions was simulated by STREAM model well. In addition, the wind speed at 151m is larger than the measurement at 353m significantly. This near-surface wind jet phenomenon was diagnosed through STREAM model. We found the hill topographic effect 1.2 km Southeastern away 101 Skyscraper and the surrounding high buildings are the major factors to form this wind jet. Temperature measurement at 101 Skyscraper has highly linear regression (R > 0.98) with radiosonde temperature data. The minimum difference of air temperature between two-layer of 101 Skyscraper happens in the early morning, 04:00 LST (hot season) to 08:00 LST (cold season). Significant temperature inversion phenomena (below 353 m) were always observed at cloudless breeze days, no matter what the seasons. The Particulate Matter (PM) measured by Taiwan Environmental Protection Agency (EPA) in Taipei Basin (15 sites) and our temporary measurements at 101 Skyscraper balconies near noon were collected, too. It showed that PM10 density at 353m height might reduce to ~70% of the ground level. But PM2.5 was seemed well-mixed in the near-surface urban boundary layer.

  14. The Great Cometary Show

    NASA Astrophysics Data System (ADS)

    2007-01-01

    The ESO Very Large Telescope Interferometer, which allows astronomers to scrutinise objects with a precision equivalent to that of a 130-m telescope, is proving itself an unequalled success every day. One of the latest instruments installed, AMBER, has led to a flurry of scientific results, an anthology of which is being published this week as special features in the research journal Astronomy & Astrophysics. ESO PR Photo 06a/07 ESO PR Photo 06a/07 The AMBER Instrument "With its unique capabilities, the VLT Interferometer (VLTI) has created itself a niche in which it provide answers to many astronomical questions, from the shape of stars, to discs around stars, to the surroundings of the supermassive black holes in active galaxies," says Jorge Melnick (ESO), the VLT Project Scientist. The VLTI has led to 55 scientific papers already and is in fact producing more than half of the interferometric results worldwide. "With the capability of AMBER to combine up to three of the 8.2-m VLT Unit Telescopes, we can really achieve what nobody else can do," added Fabien Malbet, from the LAOG (France) and the AMBER Project Scientist. Eleven articles will appear this week in Astronomy & Astrophysics' special AMBER section. Three of them describe the unique instrument, while the other eight reveal completely new results about the early and late stages in the life of stars. ESO PR Photo 06b/07 ESO PR Photo 06b/07 The Inner Winds of Eta Carinae The first results presented in this issue cover various fields of stellar and circumstellar physics. Two papers deal with very young solar-like stars, offering new information about the geometry of the surrounding discs and associated outflowing winds. Other articles are devoted to the study of hot active stars of particular interest: Alpha Arae, Kappa Canis Majoris, and CPD -57o2874. They provide new, precise information about their rotating gas envelopes. An important new result concerns the enigmatic object Eta Carinae. Using AMBER with its high spatial and spectral resolution, it was possible to zoom into the very heart of this very massive star. In this innermost region, the observations are dominated by the extremely dense stellar wind that totally obscures the underlying central star. The AMBER observations show that this dense stellar wind is not spherically symmetric, but exhibits a clearly elongated structure. Overall, the AMBER observations confirm that the extremely high mass loss of Eta Carinae's massive central star is non-spherical and much stronger along the poles than in the equatorial plane. This is in agreement with theoretical models that predict such an enhanced polar mass-loss in the case of rapidly rotating stars. ESO PR Photo 06c/07 ESO PR Photo 06c/07 RS Ophiuchi in Outburst Several papers from this special feature focus on the later stages in a star's life. One looks at the binary system Gamma 2 Velorum, which contains the closest example of a star known as a Wolf-Rayet. A single AMBER observation allowed the astronomers to separate the spectra of the two components, offering new insights in the modeling of Wolf-Rayet stars, but made it also possible to measure the separation between the two stars. This led to a new determination of the distance of the system, showing that previous estimates were incorrect. The observations also revealed information on the region where the winds from the two stars collide. The famous binary system RS Ophiuchi, an example of a recurrent nova, was observed just 5 days after it was discovered to be in outburst on 12 February 2006, an event that has been expected for 21 years. AMBER was able to detect the extension of the expanding nova emission. These observations show a complex geometry and kinematics, far from the simple interpretation of a spherical fireball in extension. AMBER has detected a high velocity jet probably perpendicular to the orbital plane of the binary system, and allowed a precise and careful study of the wind and the shockwave coming from the nova. The stream of results from the VLTI and AMBER

  15. Regolith thickness of the lunar nearside: Preliminary results from Earth-based 70 cm radar observations

    NASA Astrophysics Data System (ADS)

    Fa, W.; Wieczorek, M. A.

    2010-12-01

    Previous investigations have shown that lunar surface consists of a fine-grained regolith layer that completely covers the underlying bedrock. The lunar regolith is a byproduct of the continuous impact of large and small meteoroids with the lunar surface, and consists largely of fragmented materials and breccias. In general, the thickness of the regolith is an indication of the age of lunar surface: the older the age, the greater the thickness. The regolith contains potentially valuable resources and volatiles (such as ice and helium-3), and all future human activates will use regolith for building materials and shielding. Therefore, knowledge of the regolith layer thickness provides important information about both lunar geology and for future lunar exploration. The regolith thickness over small regions has been estimated previously from direct measurements made during the Apollo missions (such as seismic and multifrequency electromagnetic probing experiments), as well as studies of impact crater morphology and crater size-frequency distributions. From these studies, the average thickness of the regolith is believed to be about 4-5 m in the maria and 10-15 m in the older highland regions. Recently, remote sensing techniques, such as Earth-based radar, Chang-E microwave radiometery, and Kaguya lunar radar sounding, have been used to invert for regolith thickness over large regions. However, the uncertainties in the calibration of these data and the use of a simplified regolith model that did not consider buried rocks have limited the utility of these techniques. In this study, a rigorous radar scattering model based on vector radiative transfer theory and the newly acquired Earth-based 70 cm radar data are used to invert for a much more accurate regolith map for the lunar nearside hemisphere. Three parameters are required for radar studies of the regolith: regolith dielectric permittivity, surface roughness, and subsurface rock size and abundance. Our reinvestigation of the measured dielectric properties of the Apollo samples shows that, when normalized to a constant density (or porosity), the relative permittivity is constant and the loss tangent depends only on the abundance of TiO2. The dielectric permittivity across the lunar surface is then estimated globally using this relation and the regolith composition derived from the Lunar Prospector ?-ray spectrometer. Second, we estimated the surface roughness and abundance of subsurface rocks at the Apollo landing sites, where the regolith thickness and composition are known. Preliminary result shows that, at the scale of 70 cm wavelength, the rms slope of the lunar surface is around 2-10, and highlands are rougher than the maria. The average population of buried rocks in the regolith is about 0.5 per m3 for effective sizes of 6 cm. Extrapolating these surface roughness and rock abundances globally, we inverted for the regolith thickness using the Earth-based 70 cm opposite sense radar data. Preliminary results show that the regolith thickness of over the maria is smaller than the highlands by at least a factor of 2. The correlation between regolith thickness and lunar surface age is currently being analyzed.

  16. Physical characteristics of the meteoroids by the results of combined radar and optical observations

    NASA Astrophysics Data System (ADS)

    Mirhusen, Narziev

    This paper proposes a method determining of the light and ionization curves by the results of combined radio - TV observations meteors in 1978-1980 in Hissar Astronomical Observatory of the Institute of Astrophysics of Sciences of Tajikistan, the calculation results of photographic and radar meteoroid mass and analysis of the shape of light curves of meteors within the theory of evaporation and the theory of the quasi-continuous fragmentation. The photographic meteoroid mass from the light curve were defined: a) by the value of maximum luminescence intensity at the height hm and b) by the integration light curve. It is based on analysis of the data of the mass were obtained correction factor that takes into account the effect of fragmentation and other factors to determine the mass of meteoroids first method. Average value of the mass of meteoroids calculated by the light curve for meteors with magnitude M?1 is 19.10-3 g, and the average value of the mass found on magnitude of the luminescence intensity at the height the maximum brightness consist 18.2.10-3 that is in satisfactory agreement. The meteoroids masses was calculated also radio method by value of maximum linear electron density at the height of maximum ionization (n). The framework of the classical theory and the theory quasi-continuous fragmentation, the shape of the light curves of simultaneous radio - optical meteors were analyzed. It is shown that the main mechanism of ablation 60% of simultaneous radio - optical meteors is a quasi-continuous fragmentation. The bulk density and porosity of showers and sporadic meteoroids were determined. Found that the Geminids meteoroids and ?-Aquariids have the largest bulk densities (?o = 3.6 g/cm3). A meteoroids of the showers Orionids and Leonids have the lowest bulk density (?o ? 0.6 g/cm3), and the highest value of the porosity (60 ? K ? 80%). The mass fragments of flow and sporadic meteoroids lie in the range of 5.10-810-5g.

  17. Preliminary Results from Recent Simultaneous Chandra/HST Observations of Jupiter Auroral Zones

    NASA Technical Reports Server (NTRS)

    Elsner, R.; Gladstone, R.; Waite, H.; Majeed, T.; Ford, P.; Grodent, D.; Bwardwaj, A.; Howell, R.; Cravens, T.; MacDowell, R.

    2003-01-01

    Jupiter was observed by the Chandra X-ray Observatory in late February, 2003, for 144 ks, using both the ACIS-S and HRC-I imaging x-ray cameras. Five orbits of HST STIS observations of the planet's northern auroral zone were obtained during the ACIS-S observations. These data are providing a wealth of information about Jupiter's auroral activity, including the first x-ray spectra from the x-ray hot spots inside the auroral ovals. We will also discuss the approximately 45 minute quasi-periodicity in the auroral x-ray emission - which correlates well with simultaneous observations of radio bursts by the Ulysses spacecraft - and a possible phase relation between the emission from the northern and southern x-ray aurora.

  18. Comparing offshore wind farm wake observed from satellite SAR and wake model results

    NASA Astrophysics Data System (ADS)

    Bay Hasager, Charlotte

    2014-05-01

    Offshore winds can be observed from satellite synthetic aperture radar (SAR). In the FP7 EERA DTOC project, the European Energy Research Alliance project on Design Tools for Offshore Wind Farm Clusters, there is focus on mid- to far-field wind farm wakes. The more wind farms are constructed nearby other wind farms, the more is the potential loss in annual energy production in all neighboring wind farms due to wind farm cluster effects. It is of course dependent upon the prevailing wind directions and wind speed levels, the distance between the wind farms, the wind turbine sizes and spacing. Some knowledge is available within wind farm arrays and in the near-field from various investigations. There are 58 offshore wind farms in the Northern European seas grid connected and in operation. Several of those are spaced near each other. There are several twin wind farms in operation including Nysted-1 and Rødsand-2 in the Baltic Sea, and Horns Rev 1 and Horns Rev 2, Egmond aan Zee and Prinses Amalia, and Thompton 1 and Thompton 2 all in the North Sea. There are ambitious plans of constructing numerous wind farms - great clusters of offshore wind farms. Current investigation of offshore wind farms includes mapping from high-resolution satellite SAR of several of the offshore wind farms in operation in the North Sea. Around 20 images with wind farm wake cases have been retrieved and processed. The data are from the Canadian RADARSAT-1/-2 satellites. These observe in microwave C-band and have been used for ocean surface wind retrieval during several years. The satellite wind maps are valid at 10 m above sea level. The wakes are identified in the raw images as darker areas downwind of the wind farms. In the SAR-based wind maps the wake deficit is found as areas of lower winds downwind of the wind farms compared to parallel undisturbed flow in the flow direction. The wind direction is clearly visible from lee effects and wind streaks in the images. The wind farm wake cases are modeled by various types of wake models. In the EERA DTOC project the model suite consists of engineering models (Ainslie, DWM, GLC, PARK, WASP/NOJ), simplified CFD models (FUGA, FarmFlow), full CFD models (CRES-flowNS, RANS), mesoscale model (SKIRON, WRF) and coupled meso-scale and microscale models. The comparison analysis between the satellite wind wake and model results will be presented and discussed. It is first time a comprehensive analysis is performed on this subject. The topic gains increasing importance because there is a growing need to precisely model also mid- and far-field wind farms wakes for development and planning of offshore wind farm clusters.

  19. First Year Results from the Circumarctic Lakes Observation Network (CALON) Project

    NASA Astrophysics Data System (ADS)

    Hinkel, K. M.; Arp, C. D.; Frey, K. E.; Lenters, J. D.; Beck, R. A.; Eisner, W. R.; Gaglioti, B.; Grosse, G.; Jones, B. M.; Kim, C.; Liu, H.; Townsend-Small, A.

    2012-12-01

    In April 2012, instruments were deployed in over 50 lakes in northern Alaska as the initial phase of CALON, a project designed to observe short- and long-term variability in physical, limnological and biogeochemical processes in Arctic lakes. The network currently consists of nine observation nodes on two parallel transects extending from the Arctic Ocean south to the Brooks Range Foothills. At each node, at least six representative lakes that vary by surface area and depth were instrumented at different intensity levels: basic, enhanced and comprehensive. At each node we deployed a suite of instrumentation and collected a variety of field measurements. This approach allows for the study of lakes and their diversity across strong physical and biological gradients. To date we have established sites at a wide variety of Arctic lake types; 25 are thermokarst lakes set in ice-rich, fine-grained marine surficial sediments (Outer Coastal Plain), 6 lakes are in alluvial/aeolian sediments (Inner Coastal Plain) and 6 are in ice-rich silt (Arctic Foothills Yedoma), 5 are depressional lakes formed in a late Pleistocene sand sheet (Ikpikpuk Sand Sea), 6 represent glacial thermokarst or kettle lakes near the Brooks Range (Toolik region), 7 lakes are of fluvial or deltaic origin (Fish Creek basin, Ikpikpuk Delta), and Teshekpuk Lake, the largest lake in Arctic Alaska, is of a complex origin. In April, sensors measuring water temperature and water depth were deployed through the ice cover, water samples were collected, and real-time time lapse cameras were installed to capture snow melt and ice-off. Sensors were recovered from lakes and meteorological stations in August, recording lake regimes and events from ice decay and snowmelt influx to open-water warming and water balance. In general, lake ice thickness increased with latitude; in lakes deeper than 2 m, ice was about 1.4 m thick in the Arctic Foothills and 1.7 m thick near the coast of the Arctic Ocean with inter-lake variability related to snow depth. Rapid warming follows ice-off, with water temperature responding synchronously to synoptic weather variations across the area. Regionally, ice-off occurs 2-4 weeks later on lakes near the coast, but with high inter-lake variability related to lake depth and area. Inland lakes are warmer in mid-summer than those near the coast, reflecting the regional climate gradient and the maritime effect. All lakes are well-mixed and largely isothermal, with some thermal stratification occurring during calm, sunny periods in deeper lakes. This project also involves measurement of carbon and nutrient dynamics and inorganic geochemistry of the lakes. Preliminary data indicate that brown colored lakes have greater dissolved methane concentrations under ice in winter than clear-water lakes, which is promising for remote sensing applications. Through a collaborative effort between the USGS-Alaska Science Center, the BLM Arctic Field Office, the NSF and other partners, we have established the Teshekpuk Lake Observatory as part of the CALON project in order to assess the past, present, and future response of Teshekpuk Lake ecosystem to environmental stressors and change. All data resulting from this 4-year project will be stored at CADIS and a specially designed web portal, and is currently accessible through the CALON web page at https://sites.google.com/a/giesn.com/nsf-calon/.

  20. Ecological Controls on Biogeochemical Fluxes in the Western Antarctic Peninsula: Long-Term Observations and Inverse Food Web Model Results

    NASA Astrophysics Data System (ADS)

    Ducklow, H. W.; Sailley, S. F.; Stammerjohn, S. E.; Saba, G. K.; Doney, S. C.

    2014-12-01

    Sea ice in the Western Antarctic Peninsula (WAP) region is both highly variable and rapidly changing. In the Palmer Station region, the ice season duration has decreased by 92 days since 1978. The sea-ice changes affect ocean stratification and freshwater balance; and in turn impact every component of the polar marine ecosystem. Long-term observations from the WAP shelf region show a pattern of chlorophyll (Chl) variability with three to five years of negative Chl anomalies interrupted by one or two years of positive anomalies. Observations and results from an inverse food-web model show that these low and high Chl regimes differed significantly from each other, with high primary productivity and net community production (NCP) associated with the high Chl years and vice-versa. Gross primary production averaged 40 mmolC m-2 d-1 in the low Chl years and 100 mmolC m-2 d-1 in the high Chl years, with 30-40% going to NCP across regimes. Only the food web in the southern region in high Chl years was dominated by large phytoplankton and krill, whereas in in all other cases, foodwebs were dominated by small phytoplankton and microzooplankton. These contrasts were strongest between the northern, low Chl years and southern, high Chl years, consistent with earlier north to south observations of sea ice and ecosystem change along the WAP. The relative importance of major bulk carbon flows did not differ substantially between high and low Chl years. Both the northern/low Chl and southern/high Chl regimes had roughly equal proportions of NCP, although its composition reflected shifts in dominance by large versus small plankton. These results suggest that food webs dominated by smaller phytoplankton and grazers have pathways that funnel production into NCP, and likely, export.

  1. Direct aerosol radiative forcing based on combined A-Train observations and comparisons to IPCC-2007 results

    NASA Astrophysics Data System (ADS)

    Redemann, J.; Shinozuka, Y.; Vaughan, M.; Russell, P. B.; Kacenelenbogen, M. S.; Livingston, J. M.; Torres, O.; Remer, L. A.

    2012-12-01

    We describe a technique for combining CALIOP aerosol backscatter, MODIS spectral AOD (aerosol optical depth), and OMI AAOD (absorption aerosol optical depth) measurements for the purpose of estimating full spectral sets of aerosol radiative properties, and ultimately for calculating the 3-D distribution of direct aerosol radiative forcing. As preparatory work, we carried out sensitivity studies, tested our methodology using suborbital observations, and investigated the consistency between various combinations of satellite input data sets. These studies were carried out largely to investigate the propagation of uncertainties in the multi-sensor input data into the aerosol radiative property estimates. We present results using one year of collocated CALIOP V3, MODIS and OMI data collected in 2007 and show comparisons of the aerosol radiative property estimates to collocated AERONET retrievals. An apparent bias in the input aerosol absorption optical depth and a related bias in the input aerosol single scattering albedo (SSA) are removed after application of the multi-sensor aerosol retrieval. We surmise that the removal of the SSA bias from the input data is a consequence of requiring the multi-sensor retrievals to be consistent with all input data and that the multi-sensor retrievals may be better constrained than retrievals from individual A-Train sensors. Initial calculations of seasonal clear-sky aerosol radiative forcing based on our multi-sensor aerosol retrievals compare well with over-ocean and top of the atmosphere IPCC-2007 model-based results, and with more recent assessments in the "Climate Change Science Program Report: Atmospheric Aerosol Properties and Climate Impacts" (hereafter referred to as CCSP-2009). This is noteworthy, since the observationally based estimates in CCSP-2009 did not compare well with the model-based estimates. Our multi-sensor based forcing calculations compare well with observationally based CCSP-2009 estimates at the surface, indicating that differences in column aerosol absorption properties between our assessment and the CCSP-2009 observationally based estimates need to be investigated. We emphasize that our forcing estimates are purely observational, without use of aerosol transport model assumptions. As such, our results should be well suited for comparisons to initiatives such as AeroCom (Aerosol Comparisons between Observations and Models), that ultimately aim to understand the differences in the 3-D distribution of aerosol radiative properties and effects in global aerosol models.

  2. Global Observation Research Initiative in Alpine Environments (GLORIA): Results From Four Target Regions in California

    NASA Astrophysics Data System (ADS)

    Butz, R. J.; Dennis, A.; Millar, C. I.; Westfall, R. D.

    2008-12-01

    The Global Observation Research Initiative in Alpine Environments (GLORIA) is a worldwide network of long- term research sites established to assess the impacts of climate change in sensitive native alpine communities. Many alpine species face habitat fragmentation and loss, and even extinction because they are adapted to cold temperatures and very limited in their geographic distribution. This study summarizes the data collected from four sites comprised of three to four summits each in the Sierra Nevada and White Mountain ranges of California. The 14 summits cover elevational gradients ranging from 3170m to 4285m. On each summit, habitat characteristics, species composition, species cover, and frequency counts are recorded in sixteen 1m x 1m quadrats. Additional surveys on the percentage cover of surface types and of each species in eight larger plots extending to 10m below the summit focus on detecting changes in species richness and species migrations. Sites were analyzed both independently and as a group to explore similarities and differences in species composition, plant functional groups, phenology, and response to climate. A total of 124 species were identified across all sites. The summits within each site exhibited rich, heterogeneous plant communities, but ones in which most species were infrequent. Northern slopes generally had the highest vegetation cover and eastern slopes, the lowest. Elevation, aspect, and substrate all strongly influenced community composition. The average minimum winter soil temperature varied by more than 10C between the lowest and highest sites in the gradient. Resampling over time will allow us to discern trends in species diversity and temperature, and assess and predict losses in biodiversity and other threats to these fragile alpine ecosystems. Results from this work will contribute to a predictive understanding of shifts in the distribution of alpine species with climate warming in the western U.S.; expand existing long-term data sets on the effects of climate change in alpine environments; and provide standardized, quantitative data on the altitudinal differences in species richness, species compositions, vegetation cover, soil temperature, and snow cover period.

  3. Results from the Prototype GLOBE at Night Worldwide Light Pollution Observation Program

    NASA Astrophysics Data System (ADS)

    Walker, Constance E.; Pompea, S. M.; Isbell, D.; Orellana, D.; Blurton, C.; Henderson, S.

    2006-06-01

    Students, families, and educators worldwide participated in GLOBE at Night - an international event designed to observe and record the visible stars as a means of measuring light pollution in a given location. Participation was open to anyone - anywhere in the world - who could get outside and look skyward during the week of March 22-29, 2006. Our goal was 5000 observations from around the world in this prototype program.The hands-on learning activities associated with the program were designed to extend the traditional classroom and school day with a week of nighttime observations involving teachers, students and their families. By locating specific constellations in the sky, students from around the world learned how the lights in their community contribute to light pollution. Students explored the different light sources in their community learning the relationship between science, technology and society, and they reported their observations online through a central database allowing for authentic worldwide research and analysis. The observations made during GLOBE at Night helped students and scientists together assess how the quality of the night sky varies around the world as well as the level of energy wastage associated with poorly-shielded lights.For more information, visit http://www.globe.gov/globeatnight.GLOBE at Night is a collaboration between The GLOBE Program, the National Optical Astronomy Observatory (NOAO), Centro de Apoyo a la Didactica de la Astronomia (CADIAS) in Chile , Windows to the Universe, and Environmental Systems Research Institute, Inc. (ESRI).

  4. Project Phoenix: A Summary of SETI Observations and Results, 1995 - 2004

    NASA Astrophysics Data System (ADS)

    Backus, P. R.; Project Phoenix Team

    2004-05-01

    Project Phoenix was a Search for Extraterrestrial Intelligence (SETI) that observed nearly 800 stars within about 80 parsecs over the available frequencies in the microwave spectrum from 1200 to 3000 MHz with a resolution of 0.7 Hz. The search had three major observing campaigns using the Parkes 64 meter, the NRAO 140 Foot, and the Arecibo 305 meter antennas. Phoenix used real time signal detection and immediate verification of possible ETI signals. The search looked for narrowband signals that were continuously present, or pulsed regularly, and allowed for frequency drift rates of up to about 1 Hz per second. A database of terrestrial signals found in the previous week was used to match against detections for each observation. Candidate signals, i.e., those not in the database, were checked immediately with a "pseudo-interferometric" observation using a second, distant antenna, or by simple on-off observations if the second antenna was unavailable. While millions of signals were detected, all proved to be from terrestrial technology. In conclusion, we can set upper limits on the power of narrowband transmitters in the vicinity of nearby stars. Project Phoenix was the privately-funded continuation of the NASA Targeted Search SETI program and we gratefully acknowledge the use of NASA equipment on long term loan through 2002. The search was supported by contributions from Bernard M. Oliver, William and Rosemary Hewlett, Gordon and Betty Moore, the David and Lucile Packard Foundation, and the Paul G. Allen Foundation.

  5. Observing System Simulation Experiments for Hurricanes: Early results and plans for the future

    NASA Astrophysics Data System (ADS)

    Atlas, R. M.; Pu, Z.

    2010-12-01

    Observing System Simulation Experiments (OSSEs) are an important tool for evaluating the potential impact of proposed new observing systems, as well as for evaluating trade-offs in observing system design, and in developing and assessing improved methodology for assimilating new observations. Extensive OSSEs have been conducted at NASA/GSFC and NOAA/AOML in collaboration with Simpson Weather Associates, operational data assimilation centers, and academic partners over the last 25 years. These OSSEs determined correctly the quantitative potential for several proposed satellite observing systems to improve weather analysis and prediction prior to their launch, evaluated trade-offs in orbits, coverage and accuracy for space-based wind lidars, and were used in the development of the methodology that led to the first beneficial impacts of satellite surface winds on numerical weather prediction. In this paper, we will summarize early applications of global OSSEs to hurricane track forecasting, current experiments using both global and regional models aimed at both track and intensity forecasting, and plans for future experiments.

  6. A Comparison of TWP-ICE Observational Data with Cloud-Resolving Model Results

    SciTech Connect

    Fridlind, A. M.; Ackerman, Andrew; Chaboureau, Jean-Pierre; Fan, Jiwen; Grabowski, Wojciech W.; Hill, A.; Jones, T. R.; Khaiyer, M. M.; Liu, G.; Minnis, Patrick; Morrison, H.; Nguyen, L.; Park, S.; Petch, Jon C.; Pinty, Jean-Pierre; Schumacher, Courtney; Shipway, Ben; Varble, A. C.; Wu, Xiaoqing; Xie, Shaocheng; Zhang, Minghua

    2012-03-13

    Observations made during the TWP-ICE campaign are used to drive and evaluate thirteen cloud-resolving model simulations with periodic lateral boundary conditions. The simulations employ 2D and 3D dynamics, one- and two-moment microphysics, several variations on large-scale forcing, and the use of observationally derived aerosol properties to prognose droplet numbers. When domain means are averaged over a 6-day active monsoon period, all simulations reproduce observed surface precipitation rate but not its structural distribution. Simulated fractional areas covered by convective and stratiform rain are uncorrelated with one another, and are both variably overpredicted by up to a factor of {approx}2. Stratiform area fractions are strongly anticorrelated with outgoing longwave radiation (OLR) but are negligibly correlated with ice water path (IWP), indicating that ice spatial distribution controls OLR more than mean IWP. Overpredictions of OLR tend to be accompanied by underpredictions of reflected shortwave radiation (RSR). When there are two simulations differing only in microphysics scheme or large-scale forcing, the one with smaller stratiform area tends to exhibit greater OLR and lesser RSR by similar amounts. After {approx}10 days, simulations reach a suppressed monsoon period with a wide range of mean precipitable water vapor, attributable in part to varying overprediction of cloud-modulated radiative flux divergence compared with observationally derived values. Differences across the simulation ensemble arise from multiple sources, including dynamics, microphysics, and radiation treatments. Close agreement of spatial and temporal averages with observations may not be expected, but the wide spreads of predicted stratiform fraction and anticorrelated OLR indicate a need for more rigorous observation-based evaluation of the underlying micro- and macrophysical properties of convective and stratiform structures.

  7. Lunar crater giordano bruno: a.d. 1178 impact observations consistent with laser ranging results.

    PubMed

    Calame, O; Mulholland, J D

    1978-02-24

    The hypothesis of Hartung, that the impact formation of lunar crater Giordano Bruno (103 degrees east, 36 degrees north) was observed and recorded 800 years ago, is considered in the context of data from the Luna 24 mission and laser range observations. It is concluded that (i) the event would certainly have been visible, and (ii) current determinations of the free libration in longitude in the moon's rotation are consistent with the hypothesis. Such a study cannot prove Hartung's interpretation, but it is nonetheless supportive of it. PMID:17757584

  8. Traces on sky: the classification and the results of regular observations of twilight fireballs

    NASA Astrophysics Data System (ADS)

    Churyumov, Klim I.; Steklov, Alexei F.; Vidmachenko, Anatoliy P.; Steklov, E.

    2014-12-01

    We propose to organize a small basic Observatory aerospace monitoring of dangerous fireballs for a detailed study of the Earth interaction with space environment. During the observation from March 2013 to July 2014 we recorded fall at least a dozen of comet nuclei fragments, at least five large and dozens of smaller fragments of meteoroids. So, like most countries in Europe and America, Ukraine needs to create a network of small basic aerospace monitoring observatories equipped with wide-angle lenses with a simple compact camera to measure these phenomena on a personal computer. These simple inexpensive hardware complexes should be equipped a professional observatory and university, school and amateur observation points.

  9. Observational Results of the ChangE-1 Solar X-Ray Monitor

    NASA Astrophysics Data System (ADS)

    Cui, X. Z.; Wang, H. Y.; Peng, W. X.; Zhang, C. M.; Liang, X. H.; Wang, J. Z.; Gao, M.; Yang, J. W.; Cao, X. L.; Zhang, J. Y.; Wu, M. Y.; Chang, J.; Sun, H. X.; OuYang, Z. Y.; Zhou, Y. L.; Li, C. L.

    2014-05-01

    We present the primary observations of the Solar X-ray Monitor (SXM) payload onboard the ChangE-1 lunar exploration satellite, which was launched on 24 October 2007. The SXM payload uses a solid-state silicon P-I-N photo-diode (Si-PIN) whose dynamic energy ranges from 1 keV to 10 keV. The long-term integrated spectra at different solar-activity levels as observed by the SXM are presented. By fitting these spectra with an optically thin plasma model, the two-minute temperature variation of the solar coronal plasma during a solar flare is also presented.

  10. Vertical Mixing and Chemistry Over an Arid Urban Site: First Results from Aircraft Observations Made During the Phoenix Sunrise Campaign

    SciTech Connect

    Berkowitz, Carl M. ); Springston, Stephen R.; Doran, J Christopher ); Fast, Jerome D. )

    2002-01-17

    A central goal of the Phoenix 2001 Field Campaign was to study vertical mixing with the onset of convection and to quantify the effect of this mixing on chemistry within an urban boundary layer. As part of this study, a series of low altitude aircraft sampling flights were made over the Greater Phoenix area between June 16-30, 2001. The resulting observations, in conjunction with a series of surface measurements and meteorological observations, are being used to study the vertical transport and reactivity of ozone and ozone-precursors shortly after sunrise. A typical flight began with sampling in the residual boundary layer of the preceding afternoon, showing a large vertical gradient in both chemical and meteorological species. With the development of the convective boundary layer, these gradients disappeared, and a more uniform value was found at all altitudes in the more slowly reacting species. Ozone levels were typically observed to be greatest aloft during the early morning hour s, with values typically twice those found near the surfaces. NOy was inversely related to ozone at the start of the flights, as would be expected from the O3+ NO reaction, suggesting the upward mixing of NOx rich air with the downward transport of NOx-poor, O3 rich air. The timing of the development of the convective boundary layer, as measured by the weakening of chemical stratification, appeared to be related to the intensity of the residual nocturnal stable layer.

  11. Results of a Deep Chandra Observation of the Crab Nebula and Pulsar

    NASA Technical Reports Server (NTRS)

    Weisskopf, M. C.; Becker, W.; Elsner, R. F.; Juda, M.; Kolodziejczak, J.; Murray, S. S.; ODell, S.; Paerels, F.; Shibazaki, N.; Swartz, D.; Rose, M. Franklin (Technical Monitor)

    2001-01-01

    The Crab Nebula and pulsar were observed for a total of 150 ksec with the LETG/HRC-S combination aboard the Chandra X-Ray Observatory in 2000, January and February. One of the principal aims of the experiment was to study the emission from the pulsar as a function of pulse phase. Neutron stars are believed to be formed with core temperatures of 10(exp 11) K. As the pulsar is the best studied of the young known neutron stars with an age of only 940 yrs, it should be possible to observe thermal emission from the hot stellar surface which in turn constrains equations of state. The pulsar, on the other hand, is a powerful non-thermal emitter, powering an X-ray bright synchrotron nebula which, in Einstein and ROSAT observations, overshadowed the fainter thermal surface emission. Making use of the high angular resolution provided by Chandra we were able to detect X-rays from the Crab-pulsar at all pulse phases. We discuss whether this detection is indeed of thermal emission or of a faint synchrotron component of the pulsed emission from the magnetosphere. We further comment on dynamical effects observed in the pulsar-wind outflow and the analysis of the LETG spectral data, especially near the oxygen edge.

  12. Preliminary observations and results obtained with the ultraviolet spectrometer and polarimeter. [for Solar Maximum Mission

    NASA Technical Reports Server (NTRS)

    Tandberg-Hassen, E.; Cheng, C. C.; Athay, R. G.; Beckers, J. M.; Brandt, J. C.; Chapman, R. D.; Bruner, E. C.; Henze, W.; Hyder, C. L.; Gurman, J. B.

    1981-01-01

    New observation with the Ultraviolet Spectrometer and Polarimeter (UVSP) of a number of manifestations of solar activity obtained during the first three months of Solar Maximum Mission operations are presented. Attention is given to polarimetry in sunspots, oscillations above sunspots, density diagnostics of transition-zone plasmas in active regions, and the eruptive prominence - coronal transient link.

  13. Preliminary results from the observation of DT Lupus, a newly discovered oscillating Algol binary

    NASA Astrophysics Data System (ADS)

    Middleton, C. T.

    2011-10-01

    Observations using personal telescopes in light-polluted skies in Kyalami, Johannesburg, suggest that the Algol system DT Lup be re-classified as an oscillating eclipsing Algol system. Preliminary frequency calculations produce an oscillation frequency of ~8.73 cycles per day.

  14. Single baseline GLONASS observations with VLBI: data processing and first results

    NASA Astrophysics Data System (ADS)

    Tornatore, V.; Haas, R.; Duev, D.; Pogrebenko, S.; Casey, S.; Molera Calvés, G.; Keimpema, A.

    2011-07-01

    Several tests to observe signals transmitted by GLONASS (GLObal NAvigation Satellite System) satellites have been performed using the geodetic VLBI (Very Long Baseline Interferometry) technique. The radio telescopes involved in these experiments were Medicina (Italy) and Onsala (Sweden), both equipped with L-band receivers. Observations at the stations were performed using the standard Mark4 VLBI data acquisition rack and Mark5A disk-based recorders. The goals of the observations were to develop and test the scheduling, signal acquisition and processing routines to verify the full tracking pipeline, foreseeing the cross-correlation of the recorded data on the baseline Onsala-Medicina. The natural radio source 3c286 was used as a calibrator before the starting of the satellite observation sessions. Delay models, including the tropospheric and ionospheric corrections, which are consistent for both far- and near-field sources are under development. Correlation of the calibrator signal has been performed using the DiFX software, while the satellite signals have been processed using the narrow band approach with the Metsaehovi software and analysed with a near-field delay model. Delay models both for the calibrator signals and the satellites signals, using the same geometrical, tropospheric and ionospheric models, are under investigation to make a correlation of the satellite signals possible.

  15. Direct Imaging of an Emerging Flux Rope and a Resulting Chromospheric Jet Observed by Hinode

    NASA Astrophysics Data System (ADS)

    Liu, Wei; Berger, T.; Title, A. M.; Tarbell, T. D.; DeRosa, M.

    2010-05-01

    Magnetic flux emergence has been traditionally observed on the disk by identifying changes in magnetograms. Observations near the limb offer an alternative perspective and allow direct imaging of emerging flux ropes. We present Hinode/SOT Ca II H observations of such an event in an equatorial coronal hole on 2007 February 9. The precursor of the event was a bundle of fine material threads that extended at an oblique angle above the chromosphere and appeared to rotate about a common axis. This bundle first slowly and then rapidly swung up, accompanied by a loop that appeared at the base of the bundle and expanded at comparable rates. During the first (slow rise) stage, the apex of the loop ascended at 16 km/s, a velocity similar to that of H-alpha arch filaments (e.g., Chou & Zirin) and of emerging flux ropes expanding into the corona as found in MHD simulations (e.g., Fan & Gibson; Martinez-Sykora). The second stage started at the onset of a GOES A5 flare and the loop expansion accelerated, reaching a velocity of 130 km/s when the loop appeared to rupture near the peak of the flare. The material bundle then swung back in a whiplike manner and developed into a collimated jet, exhibiting oscillatory transverse motions across its axis, as expected from unwinding twists. Some jet material fell back along smooth streamlines, which bypass an unseen dome and presumably a null point in the low corona, depicting an inverted-Y shape. Some of these observations resemble the model (e.g., Uchida & Shibata) of the emergence of a twisted flux rope into an open field region that leads to reconnection and formation of a jet. Some observations are, however, not predicted in previous models and we will discuss their implications.

  16. Results of the Workshop on Impact Cratering: Bridging the Gap Between Modeling and Observations

    NASA Technical Reports Server (NTRS)

    Herrick, Robert (Editor); Pierazzo, Elisabetta (Editor)

    2003-01-01

    On February 7-9,2003, approximately 60 scientists gathered at the Lunar and Planetary Institute in Houston, Texas, for a workshop devoted to improving knowledge of the impact cratering process. We (co-conveners Elisabetta Pierazzo and Robert Herrick) both focus research efforts on studying the impact cratering process, but the former specializes in numerical modeling while the latter draws inferences from observations of planetary craters. Significant work has been done in several key areas of impact studies over the past several years, but in many respects there seem to be a disconnect between the groups employing different approaches, in particular modeling versus observations. The goal in convening this workshop was to bring together these disparate groups to have an open dialogue for the purposes of answering outstanding questions about the impact process and setting future research directions. We were successful in getting participation from most of the major research groups studying the impact process. Participants gathered from five continents with research specialties ranging from numerical modeling to field geology, and from small-scale experimentation and geochemical sample analysis to seismology and remote sensing.With the assistance of the scientific advisory committee (Bevan French, Kevin Housen, Bill McKinnon, Jay Melosh, and Mike Zolensky), the workshop was divided into a series of sessions devoted to different aspects of the cratering process. Each session was opened by two invited t a b , one given by a specialist in numerical or experimental modeling approaches, and the other by a specialist in geological, geophysical, or geochemical observations. Shorter invited and contributed talks filled out the sessions, which were then concluded with an open discussion time. All modelers were requested to address the question of what observations would better constrain their models, and all observationists were requested to discuss how their observations can constrain modeling efforts.

  17. Analysis of Students' Responses to Contradictory Results Obtained by Simple Observation or Controlling Variables.

    ERIC Educational Resources Information Center

    Park, Jongwon; Kim, Ikgyun

    1998-01-01

    Investigates students' responses to presentations of experimental results that conflicted with their preconceptions regarding electric circuits, and how those responses varied according to the type of inquiry skills required to obtain the results. Contains 24 references. (DDR)

  18. First results from a high-speed infrared imaging system for the observation of gravity waves in OH airglow

    NASA Astrophysics Data System (ADS)

    Bittner, Michael; Hannawald, Patrick; Schmidt, Carsten; Wst, Sabine

    2015-04-01

    The OH-airglow-layer is concentrated at a height of about 87 km with a half-width of approximately 3 km. Observing the infrared emissions of the vibrational-rotational excited OH moelcules offers a unique possibility for studying atmospheric dynamics. Especially, atmospheric gravity waves are prominent features in the measurements. Since December 2013 the new imaging system FAIm (Fast Infrared Imager) for the study of smaller-scale features (both in space and time)is operational at the NDMC (Network for the Detection of Mesospheric Change, http://wdc.dlr.de/ndmc)station Oberpfaffenhofen. Covering the brightest OH vibrational bands between 1.3 and 1.7micrometer, the imaging system can acquire 2 frames per second. The field of view is approximately 50 km x 60 km at the mesopause height with a mean spatial resolution of 200 m. More than 370 nights of observation have successfully been performed already. The observations show a large variety of atmospheric waves with horizontal wavelengths down to less than 3km, different directions of propagation and phase velocities varying from nearly 0 m/s (quasi stationary waves) to more than 50 m/s. We present the experimental setup and will show first results. Especially, spatio-temporal sequences of the generation of smaller scale gravity wave fields as well as their turbulent dissipation will be shown. An outlook will be given to planned future simultaneous measurements from different stations in the alpine region in order to achieve some stereoscopic information about gravity wave fields.

  19. Chromospheric Jet and Growing "Loop" Observed by Hinode: New Evidence of Fan-spine Magnetic Topology Resulting from Flux Emergence

    NASA Astrophysics Data System (ADS)

    Liu, Wei; Berger, Thomas E.; Title, Alan M.; Tarbell, Theodore D.; Low, B. C.

    2011-02-01

    We present observations of a chromospheric jet and growing "loop" system that show new evidence of a fan-spine topology resulting from magnetic flux emergence. This event, occurring in an equatorial coronal hole on 2007 February 9, was observed by the Hinode Solar Optical Telescope in the Ca II H line in unprecedented detail. The predecessor of the jet is a bundle of fine material threads that extend above the chromosphere and appear to rotate about the bundle axis at ~50 km s-1 (period lsim200 s). These rotations or transverse oscillations propagate upward at velocities up to 786 km s-1. The bundle first slowly and then rapidly swings up, with the transition occurring at the onset of an A4.9 flare. A loop expands simultaneously in these two phases (velocity: 16-135 km s-1). Near the peak of the flare, the loop appears to rupture; simultaneous upward ejecta and mass downflows faster than free-fall appear in one of the loop legs. The material bundle then swings back in a whip-like manner and develops into a collimated jet, which is orientated along the inferred open-field lines with transverse oscillations continuing at slower rates. Some material falls back along smooth streamlines, showing no more oscillations. At low altitudes, the streamlines bifurcate at presumably a magnetic null point and bypass an inferred dome, depicting an inverted-Y geometry. These streamlines closely match in space the late Ca II H loop and X-ray flare loop. These observations are consistent with the model that flux emergence in an open-field region leads to magnetic reconnection, forming a jet and fan-spine topology. We propose that the material bundle and collimated jet represent the outer spine in quasi-static and eruptive stages, respectively, and the growing loop is a two-dimensional projection of the three-dimensional fan surface.

  20. Main results of atmospheric fine structure parameter observation in the lower thermosphere

    NASA Technical Reports Server (NTRS)

    Sidorov, V. V.; Fakhrutdinova, A. N.; Ganin, V. A.

    1987-01-01

    The capabilities of the radiometeor method of wind measurement increase with the increase of the transmitted power of radar stations fitted with goniometric systems which enables the observation of shower meteors along with sporadic background. In shower observations the meteor zone reflecting area narrows to the echo surface which is perpendicular to the flux radiant. Favorable conditions are created for singling out atmospheric disturbances in which the wave front is parallel to the echo surface which plays, in this case, the role of a frequency filter. For the first time this technique allowed wave disturbances with periods of approx. greater than 4 min. to be measured, with about a 99 percent probability of exceeding the level of the turbulence noise, during the Geminid and Perseid showers. Maximum values of such wave disturbance amplitudes were about 15 to 20 m/s, with lifetimes up to 2 hrs.

  1. NSTA-NASA Shuttle Student Involvement Project. Experiment Results: Insect Flight Observation at Zero Gravity

    NASA Technical Reports Server (NTRS)

    Nelson, T. E.; Peterson, J. R.

    1982-01-01

    The flight responses of common houseflies, velvetbean caterpillar moths, and worker honeybees were observed and filmed for a period of about 25 minutes in a zero-g environment during the third flight of the Space Shuttle Vehicle (flight number STS-3; March 22-30, 1982). Twelve fly puparia, 24 adult moths, 24 moth pupae, and 14 adult bees were loaded into an insect flight box, which was then stowed aboard the Shuttle Orbiter, the night before the STS-3 launch at NASA's Kennedy Space Center (KSC). The main purpose of the experiment was to observe and compare the flight responses of the three species of insects, which have somewhat different flight control mechanisms, under zero-g conditions.

  2. Observation of a thermally accessible triplet state resulting from rotation around a main-group ??bond.

    PubMed

    Kostenko, Arseni; Tumanskii, Boris; Karni, Miriam; Inoue, Shigeyoshi; Ichinohe, Masaaki; Sekiguchi, Akira; Apeloig, Yitzhak

    2015-10-01

    We report the first direct spectroscopic observation by electron paramagnetic resonance (EPR) spectroscopy of a triplet diradical that is formed in a thermally induced rotation around a main-group ??bond, that is, the Si?Si double bond of tetrakis(di-tert-butylmethylsilyl)disilene (1). The highly twisted ground-state geometry of singlet 1 allows access to the perpendicular triplet diradical?2 at moderate temperatures of 350-410?K. DFT-calculated zero-field splitting (ZFS) parameters of 2 accurately reproduce the experimentally observed half-field transition. Experiment and theory suggest a thermal equilibrium between 1 and 2 with a very low singlet-triplet energy gap of only 7.3?kcal?mol(-1) . PMID:26297814

  3. Spectroscopic photoelectric imaging Fabry-Perot interferometer - Its development and preliminary observational results

    NASA Technical Reports Server (NTRS)

    Smith, W. H.; Born, J.; Cochran, W. D.; Gelfand, J.

    1976-01-01

    In order to observe extended astronomical objects at high spatial and spectral resolution, we have constructed a spectroscopic photoelectric imaging Fabry-Perot interferometer (SPIFI). Among the properties chosen for the instrument are an air-spaced, piezoelectrically scanned design allowing an accurately settable free spectral range and employing a single etalon of high finesse. Careful design of the etalon mountings and optical train preserves high light throughput. We either obtain spectra of single spatial elements with a photomultiplier or use an SEC vidicon detector to record a series of images through the interferometer while scanning the wavelength in discrete steps. The latter procedure yields sufficient information to reconstruct spectral features over the entire object. For the conditions assumed, either series of observations requires only a small fraction of a rotational period for Jupiter or Saturn, for example.

  4. Three-Dimensional Numerical Simulations of Equatorial Spread F: Results and Observations in the Pacific Sector

    NASA Technical Reports Server (NTRS)

    Aveiro, H. C.; Hysell, D. L.; Caton, R. G.; Groves, K. M.; Klenzing, J.; Pfaff, R. F.; Stoneback, R.; Heelis, R. A.

    2012-01-01

    A three-dimensional numerical simulation of plasma density irregularities in the postsunset equatorial F region ionosphere leading to equatorial spread F (ESF) is described. The simulation evolves under realistic background conditions including bottomside plasma shear flow and vertical current. It also incorporates C/NOFS satellite data which partially specify the forcing. A combination of generalized Rayleigh-Taylor instability (GRT) and collisional shear instability (CSI) produces growing waveforms with key features that agree with C/NOFS satellite and ALTAIR radar observations in the Pacific sector, including features such as gross morphology and rates of development. The transient response of CSI is consistent with the observation of bottomside waves with wavelengths close to 30 km, whereas the steady state behavior of the combined instability can account for the 100+ km wavelength waves that predominate in the F region.

  5. ULF foreshock under radial IMF: THEMIS observations and global kinetic simulation Vlasiator results compared

    NASA Astrophysics Data System (ADS)

    Palmroth, M.; Archer, M.; Vainio, R.; Hietala, H.; Pfau-Kempf, Y.; Hoilijoki, S.; Hannuksela, O.; Ganse, U.; Sandroos, A.; Alfthan, S. von; Eastwood, J. P.

    2015-10-01

    For decades, monochromatic large-scale ultralow frequency (ULF) waves with a period of about 30 s have been observed upstream of the quasi-parallel bow shock. These waves typically propagate obliquely with respect to the interplanetary magnetic field (IMF), while the growth rate for the instability causing the waves is maximized parallel to the magnetic field. It has been suggested that the mechanism for the oblique propagation concerns wave refraction due to the spatial variability of the suprathermal ions, originating from the E B drift component. We investigate the ULF foreshock under a quasi-radial IMF with Vlasiator, which is a newly developed global hybrid-Vlasov simulation solving the Vlasov equation for protons, while electrons are treated as a charge-neutralizing fluid. We observe the generation of the 30 s ULF waves and compare their properties to previous literature and multipoint Time History of Events and Macroscale Interactions during Substorms (THEMIS) spacecraft observations. We find that Vlasiator reproduces the foreshock ULF waves in all reported observational aspects. We conclude that the variability of the density and velocity of the reflected back streaming ions determines the large-scale structure of the foreshock, which affects the wave frequency, wavelength, and oblique propagation. We conclude that the wave refraction may also be at work for radial IMF conditions, which has earlier been thought of as an exception to the refraction mechanism due to the small E B drift component. We suggest that additional refraction may be caused by the large-scale spatial variability of the density and velocity of the back streaming ions.

  6. In-situ observations of young contrails - overview and selected results from the CONCERT campaign

    NASA Astrophysics Data System (ADS)

    Voigt, C.; Schumann, U.; Jurkat, T.; Schuble, D.; Schlager, H.; Petzold, A.; Gayet, J.-F.; Krmer, M.; Schneider, J.; Borrmann, S.; Schmale, J.; Jessberger, P.; Hamburger, T.; Lichtenstern, M.; Scheibe, M.; Gourbeyre, C.; Meyer, J.; Kbbeler, M.; Frey, W.; Kalesse, H.; Butler, T.; Lawrence, M. G.; Holzpfel, F.; Arnold, F.; Wendisch, M.; Dpelheuer, A.; Gottschaldt, K.; Baumann, R.; Zger, M.; Slch, I.; Rautenhaus, M.; Drnbrack, A.

    2010-09-01

    Lineshaped contrails were detected with the research aircraft Falcon during the CONCERT - CONtrail and Cirrus ExpeRimenT - campaign in October/November 2008. The Falcon was equipped with a set of instruments to measure the particle size distribution, shape, extinction and chemical composition as well as trace gas mixing ratios of sulfur dioxide (SO2), reactive nitrogen and halogen species (NO, NOy, HNO3, HONO, HCl), ozone (O3) and carbon monoxide (CO). During 12 mission flights over Europe, numerous contrails, cirrus clouds and a volcanic aerosol layer were probed at altitudes between 8.5 and 11.6 km and at temperatures above 213 K. 22 contrails from 11 different aircraft were observed near and below ice saturation. The observed NO mixing ratios, ice crystal and soot number densities are compared to a process based contrail model. On 19 November 2008 the contrail from a CRJ-2 aircraft was penetrated in 10.1 km altitude at a temperature of 221 K. The contrail had mean ice crystal number densities of 125 cm-3 with effective radii reff of 2.6 ?m. The presence of particles with r>50 ?m in the less than 2 min old contrail suggests that natural cirrus crystals were entrained in the contrail. Mean HONO/NO (HONO/NOy) ratios of 0.037 (0.024) and the fuel sulfur conversion efficiency to H2SO4 (?S?) of 2.9 % observed in the CRJ-2 contrail are in the range of previous measurements in the gaseous aircraft exhaust. On 31 October 2010 aviation NO emissions could have contributed by more than 40% to the regional scale NO levels in the mid-latitude lowest stratosphere. The CONCERT observations help to better quantify the climate impact from contrails and will be used to investigate the chemical processing of trace gases on contrails.

  7. The First Result of the Precursors Observation in Karymshina Observatory (Kamchatka, Russia) for Moderate Earthquakes

    NASA Astrophysics Data System (ADS)

    Gordeev, E.; Uyeda, S.; Nagao, T.; Molchanov, O.; Hattori, K.; Lutikov, A.; Gladyshev, V.; Schekotov, A.; Chebrov, V.

    2001-12-01

    In 1999 the complex geophysical observatory was created in Kamchatka, Russia under mutual Russian-Japanese scientific project. The main purpose of this project is to investigate electromagnetic and other phenomena in connection with earthquakes. The observatory is sited in the place without any sources of industrial noise. The seismic waveforms, acoustic emission, telluric currents, magnetic pulsation and chemical composition of underground water are measured continuously. The measurements of three components of ground displacement velocity is realized by seismometer in the frequency band 0.5-40 Hz with sensitivity threshold 10-8 m/s and dynamic range of 90 dB. Triaxial induction magnetometer measures geomagnetic pulsations in the frequency range 0.003-30 Hz with sensitivity threshold 20 pT/Hz1/2 at frequency 0.01 Hz and 0.02 pT/Hz1/2 at frequencies higher than 10 Hz. Dynamic range of the magnetometer is 90 dB. Measurements of NS and EW components of telluric currents with maximum distance between electrodes of about 500 m are carried out. The acoustic emission receiver (high-frequency seismometer) based on mechanical pendulum with ceramic transducer is installed in 30 m borehole. The output signals are filtered by 4 filters with central frequencies equal to 30, 160, 500 and 1000 Hz. In the same borehole was installed high-frequency seismic noise (HFSN) piezoceramic sensor with very narrow band around 30 Hz and sensitivity threshold 10-12 m. The chemical components Cl, HCO3, SO4, Na, K, Ca, H3BO3, H4SiO4, gases CH4, N2, O2, CO2, Ar, He, H2 and hydrocarbonates C2H6, C2H4, C3H8, C3H6, C4H10, C4H10i are analysed in a few wells nearby the observatory. The atmospheric pressure, direction and velocity of the wind, humidity, precipitation, air and ground temperature are measured using meteorological station installed at observatory. Since June 2000 CGO Karymshina has started regular simultaneous monitoring of the above-mentioned parameters. Processing and analysis of the data include different methods (correlation, spectrum, wavelet and polarization). Weekly quick- looks (72 graphs) and monthly reviews are regularly distributed to Russian and Japanese collaborators. Many interesting facts are revealed from the initial scientific analysis. Rather promising results on co-seismic changes of electric and magnetic fields, on an increase of ULF noise polarization ratio 2-7 days before the large seismic shocks, and corresponding intensification of VLF signals could be mentioned in this connection. The chemical composition of underground water shows many variations in hydrocarbonates, but was not found any clear anomalies connected with earthquakes.

  8. Behavioral interactions across various aircraft types - Results of systematic observations of line operations and simulations

    NASA Technical Reports Server (NTRS)

    Clothier, Cathy C.

    1991-01-01

    The NASA/UT Line/LOS checklist is designed to capture critical components of crew interaction. The behaviors deemed critical to flight crew interaction include briefings, communications, inquiry, assertion/advocacy, and decisions communicated and acknowledged. Data shows significant behavioral interaction differences as a function of aircraft type, indicating that crew size and technology level were at least partly driving that difference.

  9. Quantitative comparison of CTIPe model results with ground and space-based observations

    NASA Astrophysics Data System (ADS)

    Fedrizzi, M.; Olsen, J. R.; Fuller-Rowell, T. J.; Codrescu, M.

    2012-12-01

    Physical models are valuable tools in the task to understand and forecast complex non-linear systems. Their value has been demonstrated in the past by comparing the output of numerical simulations with reliable observations, analyzing the driving terms in the mathematical equations, and so determine the relative importance of the various physical processes. Over the past 40 years, this methodology has enabled great advances in the scientific knowledge of the complex Sun-Earth system. However, the validation of the dynamics of the best available physics-based models has been far from comprehensive, even though the pathways for atmospheric response to forcing are apparently well understood. Energy input drives temperature and density changes, which in turn drive winds, which in turn drive changes in composition, electrodynamics, and the ionosphere. There has to be consistency in all the basic state parameters, otherwise the foundation of our perception is unfounded. This study aims to quantitatively assess the capability as well as the limitations of the global, three-dimensional, time-dependent, non-linear coupled model of the thermosphere, ionosphere, plasmasphere, and electrodynamics (CTIPe) in specifying and predicting the upper atmosphere neutral and plasma response to changes in external drivers using a comprehensive observational data set from ground and space and, at the same time, advance the understanding of the T-I system dynamics on different spatial and temporal scales. Observations from CHAMP and TIMED-GUVI satellites, ionosondes and Fabry-Perot Interferometers are among the measurements used in these model/data comparisons.

  10. Results from the NMSU-NASA Marshall Space Flight Center LCROSS observational campaign

    NASA Astrophysics Data System (ADS)

    Chanover, N. J.; Miller, C.; Hamilton, R. T.; Suggs, R. M.; McMillan, R.

    2011-08-01

    We observed the Lunar Crater Observation and Sensing Satellite (LCROSS) lunar impact on 9 October 2009 using three telescope and instrument combinations in southern New Mexico: the Agile camera with a V filter on the Astrophysical Research Consortium 3.5 m telescope at Apache Point Observatory (APO), a StellaCam video camera with an R filter on the New Mexico State University (NMSU) 1 m telescope at APO, and a Goodrich near-IR (J and H band) video camera on the NMSU 0.6 m telescope at Tortugas Mountain Observatory. The three data sets were analyzed to search for evidence of the debris plume that rose above the Cabeus crater shortly after the LCROSS impact. Although we saw no evidence of the plume in any of our data sets, we constrained its surface brightness through analysis of our photometrically calibrated data. The minimum surface brightness that we could have detected in our Agile data was 9.69 magnitudes arc sec-2, which is 177 times fainter than the brightest part of the foreground ridge of Cabeus. In our near-IR data, our minimum detectable surface brightness was 8.58 magnitudes arc sec-2, which is 370 times fainter than the brightest part of the foreground ridge in the J and H bands. The debris plume was detected by the LCROSS shepherding spacecraft and the Diviner radiometer on the Lunar Reconnaissance Orbiter. Given the plume radiance observed by LCROSS, we cannot distinguish between a conical or cylindrical plume geometry because when seen from Earth, both are below our detection thresholds.

  11. Processing results of digitized photographic observations of Pluto from the collections of the Ukrainian Virtual Observatory

    NASA Astrophysics Data System (ADS)

    Kazantseva, L. V.; Shatokhina, S. V.; Protsyuk, Yu. I.; Kovylianska, O. E.; Andruk, V. M.

    2015-01-01

    The catalogue of 59 equatorial coordinates and magnitudes of the Pluto-Charon system for the period 1961-1990 was created based on digitized photographic observations from collections of the Joint Digital Archive of the Ukrainian Virtual Observatory obtained from five telescopes of three Ukrainian observatories. Developed software and scan processing techniques were successfully used. Parametric processing models were analyzed. The mean accuracy for the equatorial coordinates of Tycho-2 reference stars on digitized astronegatives is ±90 mas. The mean error of Tycho-2 B magnitudes is ±0.32 mag. Pluto positions were compared with the ephemeris JPL PLU43-DE431.

  12. Processing results of digitized photographic observations of Pluto from the collections of the Ukrainian Virtual Observatory

    NASA Astrophysics Data System (ADS)

    Kazantseva, L. V.; Shatokhina, S. V.; Protsyuk, Yu. I.; Kovylianska, O. E.; Andruk, V. M.

    2015-01-01

    The catalogue of 59 equatorial coordinates and magnitudes of the Pluto-Charon system for the period 1961-1990 was created based on digitized photographic observations from collections of the Joint Digital Archive of the Ukrainian Virtual Observatory obtained from five telescopes of three Ukrainian observatories. Developed software and scan processing techniques were successfully used. Parametric processing models were analyzed. The mean accuracy for the equatorial coordinates of Tycho-2 reference stars on digitized astronegatives is ±90 mas. The mean error of Tycho-2 B T magnitudes is ±0.32 m . Pluto positions were compared with the ephemeris JPL PLU43-DE431.

  13. New Variable Stars Discovered by the APACHE Survey. II. Results After the Second Observing Season

    NASA Astrophysics Data System (ADS)

    Damasso, M.; Gioannini, L.; Bernagozzi, A.; Bertolini, E.; Calcidese, P.; Carbognani, A.; Cenadelli, D.; Christille, J.-M.; Giacobbe, P.; Lanteri, L.; Lattanzi, M. G.; Smart, R.; Sozzetti, A.

    2015-06-01

    Routinely operating since July 2012, the APACHE survey has celebrated its second birthday. While the main goal of the project is the detection of transiting planets around a large sample of bright, nearby M dwarfs in the northern hemisphere, the APACHE large photometric database, consisting of hundreds of different fields, represents a relevant resource to search for and provide a first characterization of new variable stars. We celebrate here the conclusion of the second year of observations by reporting the discovery of 14 new variables.

  14. Results of scatterometer systems analysis for NASA/MSC Earth Observation Sensor Evaluation Program.

    NASA Technical Reports Server (NTRS)

    Krishen, K.; Vlahos, N.; Brandt, O.; Graybeal, G.

    1971-01-01

    Radar scatterometers have applications in the NASA/MSC Earth Observation Aircraft Program. Over a period of several years, several missions have been flown over both land and ocean. In this paper a system evaluation of the NASA/MSC 13.3-GHz Scatterometer System is presented. The effects of phase error between the Scatterometer channels, antenna pattern deviations, aircraft attitude deviations, environmental changes, and other related factors such as processing errors, system repeatability, and propeller modulation, were established. Furthermore, the reduction in system errors and calibration improvement was investigated by taking into account these parameter deviations. Typical scatterometer data samples are presented.

  15. Results from the CONT02 campaign of two weeks of continuous VLBI observing

    NASA Astrophysics Data System (ADS)

    MacMillan, D.; Ma, C.; Petrov, L.

    2003-04-01

    The IVS carried out a 2-week CONT02 campaign of continuous VLBI observing from October 16-30, 2002. This is the first continuous campaign of measurements that used the Mark 4 VLBI system operating at a data rate four times as large as for similar previous continuous campaigns CONT94 and CONT96 that used the Mark 3 system. The CONT02 experiments used an 8-station network with antennas at Onsala, Kokee, Fairbanks, Ny Alesund, Algonquin Park, Westford, Wettzell, and Hartebeesthoek. Baseline length repeatabilities are at the level of about 2 mm + 0.8 ppb. Formal uncertainties of EOP measurements are 40-50 uas for polar motion and 2 us for UT1. We examine the continuity of subdaily EOP estimates from one observing day to the next. One of the primary reasons for CONT02 was to investigate the possible presence of non-harmonic signals. To do this, we analyze the series of Earth orientation parameter (EOP) estimates at 1-hour resolution after removing harmonic signals of tidal origin that we have determined from VLBI experiments from 1980-2002.

  16. Mars Pathfinder meteorological observations on the basis of results of an atmospheric global circulation model

    NASA Technical Reports Server (NTRS)

    Forget, Francois; Hourdin, F.; Talagrand, O.

    1994-01-01

    The Mars Pathfinder Meteorological Package (ASI/MET) will measure the local pressure, temperature, and winds at its future landing site, somewhere between the latitudes 0 deg N and 30 deg N. Comparable measurements have already been obtained at the surface of Mars by the Viking Landers at 22 deg N (VL1) and 48 deg N (VL2), providing much useful information on the martian atmosphere. In particular the pressure measurements contain very instructive information on the global atmospheric circulation. At the Laboratoire de Meteorologie Dynamique (LMD), we have analyzed and simulated these measurements with a martian atmospheric global circulation model (GCM), which was the first to simulate the martian atmospheric circulation over more than 1 year. The model is able to reproduce rather accurately many observed features of the martian atmosphere, including the long- and short-period oscillations of the surface pressure observed by the Viking landers. From a meteorological point of view, we think that a landing site located near or at the equator would be an interesting choice.

  17. RTT150 Planet Search Program at TUG: Results from Seven Years of Observation

    NASA Astrophysics Data System (ADS)

    Y?lmaz, M.; Selam, S. O.; Izumiura, H.; Bikmaev, I.; Sato, B.; Keskin, V.; Kambe, E.

    2015-07-01

    We have carried out a precise Doppler survey of evolved intermediate-mass stars at the TB?TAK National Observatory (TUG) since 2007 in order to detect planetary systems around these stars. For the past seven years we have been monitoring the radial velocity (RV) of 50 G-K type giants with a Doppler precision of 10 m s-1, using the Coude Echelle Spectrograph (CES) equipped with an iodine absorption cell. We have found that 9 stars show significant RV variations between 1 and 8 km s-1, while 13 targets have RV variation of 20-500 m s-1. The rest of the targets have a RV scatter of 10 m s-1. We have also found that several candidates show significant periodic RV variations that may imply the presence of stellar or substellar companions.

  18. Temporal and spatial variations of pulsating auroras obtained from ground-based observations at Poker Flat Research Range: Initial result

    NASA Astrophysics Data System (ADS)

    Nishiyama, T.; Sakanoi, T.; Miyoshi, Y.; Kataoka, R.; Katoh, Y.; Asamura, K.; Sato, M.; Okano, S.

    2011-12-01

    Pulsating Aurora(PA) is characterized by the periodically changing emission amplitudes with the rectangular pulses of a few seconds to a few tens of seconds [e.g., Oguti et al., 1981; Yamamoto, 1988]. PAs tend to appear in the recovery phase of substorm between postmidnight and dawn sector. The horizontal size of PAs are known to be 10-200 km, based on the optical observations. Recently, some ground-satellite coordinated observations suggested the generation mechanisms of PAs as a result of pitch angle scatterings due to whistler mode chorus waves and/or the electron cyclotron harmonics[Nishimura et al., 2010; Liang et al., 2010]. Time-varying field aligned potential was also suggested by Sato et al. [2004]. The dominant mechanisms and the origin of the periodicity remain unclear. Ground-based all-sky observations have been made for a long time, although they were not enough for a quantitative discussion about small-scale characteristics of PAs such as the shapes and dynamics due to their limited spatial resolutions. The fast temporal variations of intensity known as quasi-3Hz modulations, which was reported by a number of rocket/satellite observations about precipitating electrons[e.g., Sandahl et al., 1980], has been hardly discussed in detail using the ground instruments because of the limited temporal resolutions and sensitivities. We have carried out ground-based observations using a suit of instruments, consisting of an EMCCD camera, an all-sky video camera, a photometer, and a search coil magnetometer covering the frequency range of ELF-VLF. We installed the instruments at Poker Flat Research Range between November 2010 and March 2011. Our EMCCD camera has narrow field of view corresponding to 100km 100km at altitude of 110 km and high sampling rate up to 100 frames per second. An initial analysis result of event on March 4th 2011 around 1100UT revealed two important features of PAs in small scale. One is PAs in the FOV can be categorized into three regions which showed different periods. There were 1-3Hz modulations inside each patches, while there was no higher frequency modulations. In addition, simultaneous observations with the search coil demonstrated that modulations of PA ranged 1 to 3Hz correlated to ELF amplitudes integrated over frequency range of 1-10Hz. On the other hand, VLF emissions corresponding to whistler mode waves were not seen during this period. Isolated PA seen around UT14:30 on the same day showed continuous modulations with peak at 3Hz and no correlations to ELF amplitudes. These results demonstrate that the temporal and spatial characteristics of PA, such as periodicity, modulation and micro-shapes, varies considerably with MLT in a narrow region corresponding to about 2000km 2000km in the magnetosphere. It means that the generation processes depend greatly on local plasma conditions and the conditions are nonuniform in the source regions.

  19. Mars Global Surveyor TES Results: Observations of Atmospheric Dust During Mapping

    NASA Technical Reports Server (NTRS)

    Smith, Michael D.; Pearl, J. C.; Conrath, B. J.; Christensen, P. R.

    1999-01-01

    The Mars Global Surveyor entered mapping orbit around Mars in March 1999. Infrared spectra returned by the Thermal Emission Spectrometer (TES) are very well suited for monitoring column-integrated infrared dust opacity. A global view of dust opacity is possible on a daily basis allowing the detailed study of the evolution of dust storms and the seasonal trend of the background dust opacity. Information about the vertical distribution of dust in the atmosphere can be obtained by examination of TES spectra taken in a limb-viewing geometry. We report here on 1) the observed horizontal distribution of dust aerosols and their evolution with time during the mapping phase of the Mars Global Surveyor mission so far (roughly covering northern hemisphere summer and early fall), and 2) the vertical distribution of dust aerosols as determined from TES spectra taken in the limb-viewing geometry.

  20. New results on the microstructure of amorphous silicon as observed by internal friction

    SciTech Connect

    Crandall, R.S.; Mahan, A.H.; Iwaniczko, E.; Jones, K.M.; Liu, X.; White, B.E. Jr.; Pohl, R.O.

    1997-07-01

    The authors have measured the low temperature internal friction (Q{sup {minus}1}) of amorphous silicon (a-Si) films. Electron-beam evaporation leads to the well-known temperature-independent Q{sub 0}{sup {minus}1} plateau common to all amorphous solids. For hydrogenated amorphous silicon (a-Si:H) with about 1 at.% H produced by hot wire chemical vapor deposition, however, the value of Q{sub 0}{sup {minus}1} is over two hundred times smaller than for e-beam a-Si. This is the first observation of an amorphous solid without any significant low energy excitations. This finding offers the opportunity to study amorphous solids containing controlled densities of tunneling defects, and thus to explore their nature.

  1. MARIE: Current Status and Results from 20 Months of Observations at Mars

    NASA Technical Reports Server (NTRS)

    Zeitlin, C.; Andersen, V.; Atwell, W.; Cleghorn, T. F.; Cucinotta, F. A.; Lee, K. T.; Pinsky, L.; Saganti, P.

    2004-01-01

    The MARIE instrument aboard the 2001 Mars Odyssey spacecraft detects energetic charged particles in the Galactic Cosmic Radiation (GCR) and during solar particle events (SPE) [1]. As of this writing (January 2004), MARIE has been turned off, after losing communication with the spacecraft during the large SPE of October 28, 2003. However, during the prior 20 months, MARIE collected data almost continuously, observing several solar events and the nearly-constant GCR. There is still a possibility the instrument can be recovered, and troubleshooting efforts are scheduled to begin in May 2004, following the completion of the primary missions of MER-A (Spirit) and MER-B (Opportunity). At present, Odyssey is acting as a telecommunications relay for the rovers and only routine science operations are permitted in this mode.

  2. New Variable Stars Discovered by the APACHE Survey. I. Results After the First Observing Season

    NASA Astrophysics Data System (ADS)

    Damasso, M.; Bernagozzi, A.; Bertolini, E.; Calcidese, P.; Carbognani, A.; Cenadelli, D.; Christille, J. M.; Giacibbe, P.; Lanteri, L.; Lattanzi, M. G.; Smart, R.; Sozzetti, A.

    2014-06-01

    We present more than 80 new variable stars discovered during the first observing season of the APACHE survey. APACHE is a project aimed at detecting extrasolar planets transiting nearby, bright M dwarfs by using an array of small-aperture telescopes. Despite that the survey is targeted to a well-defined sample of cool stars, we also reduce and analyze data for all the detected field stars. Since July 2012 dozens of different stellar fields have been monitored, leading to the detection of several variables for which we propose a classification and estimate a period, when a periodicity is evident in the data. Thanks to the SuperWASP public archive, we have also retrieved and analyzed photometric data collected by the SWASP survey, which helped us to refine the classification and the period estimation of many variables found in the APACHE database. Some of the variables present peculiarities and thus are discussed separately.

  3. Results of UHF radar observation of the nocturnal low-level jet for wind energy applications

    NASA Astrophysics Data System (ADS)

    Madougou, Sadou; Sad, Frederique; Campistron, Bernard; Lothon, Marie; Kebe, Cheikh

    2012-10-01

    We use two series of eight-month UHF radar observations collected during the dry and wet seasons of AMMA field campaign. The ultimate goal is to do preliminary work to know whether the lowest layers are suitable for wind energy applications. Surface wind is usually weak in West Africa, but the regular occurrence of a nocturnal low level jet (NLLJ) could provide interesting conditions for wind energy. This work is two-fold: it first aims at improving our knowledge about the NLLJ in West Africa regarding its structure and its variability during the year. Then, special attention is paid to the first 200 m agl, to study the possibility to use the sub-jet wind as a source of energy. A set of enhanced radio-soundings is taken to help to understand the dynamics and thermodynamics and to find a way to extrapolate the wind at low level, where the UHF radars do not provide data.

  4. Magnetic Field and Plasma Observations at Mars: Initial Results of the Mars Global Surveyor Mission

    PubMed

    Acua; Connerney; Wasilewski; Lin; Anderson; Carlson; McFadden; Curtis; Mitchell; Reme; Mazelle; Sauvaud; d'Uston; Cros; Medale; Bauer; Cloutier; Mayhew; Winterhalter; Ness

    1998-03-13

    The magnetometer and electron reflectometer investigation (MAG/ER) on the Mars Global Surveyor spacecraft has obtained magnetic field and plasma observations throughout the near-Mars environment, from beyond the influence of Mars to just above the surface (at an altitude of approximately 100 kilometers). The solar wind interaction with Mars is in many ways similar to that at Venus and at an active comet, that is, primarily an ionospheric-atmospheric interaction. No significant planetary magnetic field of global scale has been detected to date (<2 x 10(21) Gauss-cubic centimeter), but here the discovery of multiple magnetic anomalies of small spatial scale in the crust of Mars is reported. PMID:9497279

  5. New Observations of Balmer Continuum Flux in Solar Flares - Instrument Description and First Results

    NASA Astrophysics Data System (ADS)

    Kotrč, P.; Procházka, O.; Heinzel, P.

    2016-02-01

    Increase in the Balmer continuum radiation during solar flares was predicted by various authors, but has never been firmly confirmed observationally using ground-based slit spectrographs. Here we describe a new post-focal instrument, the image selector, with which the Balmer continuum flux can be measured from the whole flare area, in analogy to successful detections of flaring dMe stars. The system was developed and put into operation at the horizontal solar telescope HSFA2 of the Ondřejov Observatory. We measure the total flux by a fast spectrometer from a limited but well-defined region on the solar disk. Using a system of diaphragms, the disturbing contribution of a bright solar disk can be eliminated as much as possible. Light curves of the measured flux in the spectral range 350 - 440 nm are processed, together with the H\\upalpha images of the flaring area delimited by the appropriate diaphragm. The spectral flux data are flat-fielded, calibrated, and processed to be compared with model predictions. Our analysis of the data proves that the described device is sufficiently sensitive to detect variations in the Balmer continuum during solar flares. Assuming that the Balmer-continuum kernels have at least a similar size as those visible in H\\upalpha, we find the flux increase in the Balmer continuum to reach 230 - 550 % of the quiet continuum during the observed X-class flare. We also found temporal changes in the Balmer continuum flux starting well before the onset of the flare in H\\upalpha.

  6. Measurements of formaldehyde total content in troposphere using DOAS technique in Moscow Region: preliminary results of three year observations

    NASA Astrophysics Data System (ADS)

    Postylyakov, Oleg; Borovski, Alexander; Elokhov, Alexander; Dzhola, Anatoly; Grechko, Evgeny; Kanaya, Yugo

    2014-10-01

    Measurements of the formaldehyde (HCHO) atmospheric column are performed at Zvenigorod Scientific Station, Moscow Region, Russia since 2008 by the MAX-DOAS instrument. A previously developed algorithm for the formaldehyde retrieval was updated by adding an availability to use information on the surface albedo and the height of the atmospheric boundary layer provided by other measurements and/or modeling. We present preliminary results of the analysis of observations performed in 2010-2012. The obtained data allow quantifying the Moscow megapolis influence on air quality at Zvenigorod. The average HCHO vertical column density observed at the east winds is larger than one at the west winds. The Moscow influence causes the difference of about 0.851016 mol cm-2 between these values. This difference slightly depends on the air temperature and the season. A temperature effect is noticeable in the formaldehyde atmospheric column. Our data show statistically significant positive temperature effect in formaldehyde for the background and polluted conditions for temperatures from -5C to +35C. The temperature trend in formaldehyde data at Zvenigorod varies between 7.51014 and 9.31014 mol cm-2 C-1 for all wind directions. The increase of the formaldehyde atmospheric column with the increase of the air temperature can be caused by the HCHO formation from non-methane biogenic volatile organic compounds (mainly - isoprene) for which more emission is expected at higher temperatures, and by growth of areas of forest and turf fires.

  7. Peak Bagging of red giant stars observed by Kepler: first results with a new method based on Bayesian nested sampling

    NASA Astrophysics Data System (ADS)

    Corsaro, Enrico; De Ridder, Joris

    2015-09-01

    The peak bagging analysis, namely the fitting and identification of single oscillation modes in stars' power spectra, coupled to the very high-quality light curves of red giant stars observed by Kepler, can play a crucial role for studying stellar oscillations of different flavor with an unprecedented level of detail. A thorough study of stellar oscillations would thus allow for deeper testing of stellar structure models and new insights in stellar evolution theory. However, peak bagging inferences are in general very challenging problems due to the large number of observed oscillation modes, hence of free parameters that can be involved in the fitting models. Efficiency and robustness in performing the analysis is what may be needed to proceed further. For this purpose, we developed a new code implementing the Nested Sampling Monte Carlo (NSMC) algorithm, a powerful statistical method well suited for Bayesian analyses of complex problems. In this talk we show the peak bagging of a sample of high signal-to-noise red giant stars by exploiting recent Kepler datasets and a new criterion for the detection of an oscillation mode based on the computation of the Bayesian evidence. Preliminary results for frequencies and lifetimes for single oscillation modes, together with acoustic glitches, are therefore presented.

  8. Stratospheric Clouds at South Pole During 1988 1. Results of Lidar Observations and Their Relationship to Temperature

    NASA Astrophysics Data System (ADS)

    Fiocco, Giorgio; Cacciani, Marco; Di Girolamo, Paolo; Fu, Danielle; DeLuisi, John

    1992-04-01

    An optical radar-lidar-has been operational at the Amundsen-Scott South Pole Station since summer 1987-1988. The observations were specially directed to the detection of aerosol layers and polar stratospheric clouds (PSCs). The lidar utilized a Nd-YAG laser followed by a second harmonic generator, and a 0.5-m diameter Cassegrain receiving telescope. Results obtained during the period May-October 1988 are summarized. Some 10,000 profiles of the lidar echoes, each the result of 1-min averaging, were obtained. Data sets consisting of profiles of the scattering ratio and of the backscattering cross section Ba, based on half-hour averaging, are presented. The data can be related to profiles of the atmospheric temperature T, usually obtained on a daily basis at South Pole. Stratifications appear to have two distinct types of structures: one structure shows only a modest variation with height; the other is characterized by sharp features, with large changes of the cross section with height. The basic results, the relationship between Ba, and T, and their statistical relevance are considered in this paper. The microphysical interpretation, the attribution of these structures to PSC Type I and Type II, respectively involving the condensation of nitric acid trihydrate and of water ice, and the seasonal evolution of the phenomena are treated in a companion paper.

  9. Is the observed chemical heterogeneity of the Hawaiian mantle plume real or a result of melting and mixing processes?

    NASA Astrophysics Data System (ADS)

    Stroncik, N. A.; Krsmann, T.; Niedermann, S.; Erzinger, J.

    2008-12-01

    The chemical and isotopic heterogeneity of lavas derived from Hawaiian volcanoes has resulted in a standard model of a compositionally zoned Hawaiian mantle plume. Particularly He isotope data from Loihi, Mauna Loa and Mauna Kea have been interpreted in terms of a concentrically zoned plume, with some of the Hawaiian volcanoes having never been above the plume center. Based on He, Ne and Ar fusion data from olivines derived from Mauna Kea (surface and Hawaii Scientific Drilling Project samples), Mauna Loa, Kilauea and Kohala (Big Island) as well as Haleakala (Maui) we show that the Hawaiian plume might not be zoned but that the heterogeneities observed in the lavas can be derived from melting and mixing processes. This is in accordance with other, recently developed models. The He isotopic ratios of the studied samples vary from 7 to 18 RA, whereas Ne isotopic ratios plot along the Loihi-Kilauea line in a Ne-three isotope plot. Thus the He isotopes range from ratios typical for the upper mantle to ratios more typical for a primitive mantle source. All Ne isotopic ratios are typical for a more primitive mantle. This indicates a decoupling of He from Ne as well as a homogeneous plume source. Combined He, Ne and Ar systematics show that this decoupling is caused by predegassing fractionation process, which leaves the He isotope ratio more susceptible for changes than Ne or Ar isotope ratios. Basically, this process caused a He deficit of melts generated by the plume, as shown by 3He/22Ne below current estimates of solar composition and 4He*/21Ne* and 4He*/40Ar* lower than the theoretical production ratios. These observations can best be explained by a model in which He is fractionated from Ne and Ar during formation of plume melts generated by low melting degrees and subsequent mixing with upper mantle melts generated by higher degrees of melting. This requires He to be more compatible during melt formation than Ne and Ar. Depending on the relative proportion of mixing the resulting lavas will cover the whole observed He isotope range, whereas Ne isotopes remain relatively homogeneously distributed.

  10. Long-acting paliperidone palmitate - interim results of an observational study of its effect on hospitalization.

    PubMed

    Taylor, David; Olofinjana, Olubanke

    2014-07-01

    Paliperidone palmitate (PP) is a recently introduced long-acting atypical, or second-generation, antipsychotic. Published data on PP are currently limited to controlled trials and case reports. In this observational study, we followed up 200 consecutive patients prescribed PP in normal practice. After 1 year, 65% of patients were still receiving PP. The number of admissions to hospital in the year following PP initiation was 0.49/patient compared with 0.69/patient/year, 3 years before initiation (P=0.0001). The mean number of bed days fell from 38.78 to 23.09/patient/year over the corresponding period (P=0.0001). The median number of bed days 3 years before PP initiation was 21.50/year and in the year following PP initiation, it was 0. Outcomes were numerically but not statistically better in those continuing PP than in those who ceased PP within a year of initiation. PP was effective and well-tolerated and, given its positive effect on hospital bed days, broadly cost-effective. PMID:24419004

  11. Preliminary results and status report of the Hawaiian Scientific Observation Hole program

    SciTech Connect

    Olson, Harry J.; Deymonaz, John E.

    1992-01-01

    The Hawaii Natural Energy Institute (HNEI), an institute within the School of Ocean and Earth Science and Technology, at the University of Hawaii at Manoa has drilled three Scientific Observation Holes (SOH) in the Kilauea East Rift Zone to assess the geothermal potential of the Big Island of Hawaii, and to stimulate private development of the resource. The first hole drilled, SOH-4, reached a depth of 2,000 meters and recorded a bottom hole temperature of 306 C. Although evidence of fossil reservoir conditions were encountered, no zones with obvious reservoir potential were found. The second hole, SOH- 1, was drilled to a depth of 1,684 meters, recorded a bottom hole temperature of 206.1 C and effectively defined the northern limit of the Hawaii Geothermal Project-Abbott--Puna Geothermal Venture (HGP-A/PGV) reservoir. The final hole, SOH-2, was drilled to a depth of 2,073 meters, recorded a bottom hole temperature of 350.5 C and has sufficient indicated permeability to be designated as a potential ''discovery''. The SOH program was also highly successful in developing slim hole drilling techniques and establishing subsurface geological conditions.

  12. Arctic Mixed-Phase Cloud Properties from AERI Lidar Observations: Algorithm and Results from SHEBA

    SciTech Connect

    Turner, David D.

    2005-04-01

    A new approach to retrieve microphysical properties from mixed-phase Arctic clouds is presented. This mixed-phase cloud property retrieval algorithm (MIXCRA) retrieves cloud optical depth, ice fraction, and the effective radius of the water and ice particles from ground-based, high-resolution infrared radiance and lidar cloud boundary observations. The theoretical basis for this technique is that the absorption coefficient of ice is greater than that of liquid water from 10 to 13 ?m, whereas liquid water is more absorbing than ice from 16 to 25 ?m. MIXCRA retrievals are only valid for optically thin (?visible < 6) single-layer clouds when the precipitable water vapor is less than 1 cm. MIXCRA was applied to the Atmospheric Emitted Radiance Interferometer (AERI) data that were collected during the Surface Heat Budget of the Arctic Ocean (SHEBA) experiment from November 1997 to May 1998, where 63% of all of the cloudy scenes above the SHEBA site met this specification. The retrieval determined that approximately 48% of these clouds were mixed phase and that a significant number of clouds (during all 7 months) contained liquid water, even for cloud temperatures as low as 240 K. The retrieved distributions of effective radii for water and ice particles in single-phase clouds are shown to be different than the effective radii in mixed-phase clouds.

  13. Preliminary results on Saturn's inner plasmasphere as observed by Cassini: Comparison with Voyager

    NASA Astrophysics Data System (ADS)

    Sittler, E. C.; Thomsen, M.; Chornay, D.; Shappirio, M. D.; Simpson, D.; Johnson, R. E.; Smith, H. T.; Coates, A. J.; Rymer, A. M.; Crary, F.; McComas, D. J.; Young, D. T.; Reisenfeld, D.; Dougherty, M.; Andre, N.

    2005-06-01

    We present an analysis of Saturn's inner plasmasphere as observed by the Cassini Plasma Spectrometer (CAPS) experiment during Cassini's initial entry into Saturn's magnetosphere when the spacecraft was inserted into orbit around Saturn. The ion fluxes are divided into two sub-groups: protons and water group ions. We present the relative amounts of these two groups and the first estimates of their fluid parameters: ion density, flow velocity and temperature. We also compare this data with electron plasma measurements. Within the plasmasphere and inside of Enceladus' orbit, water group ions are about a factor of ~10 greater than protons in number with number densities exceeding 40 cm-3. Within this inner region the spacecraft acquires a negative potential so that the electron density is underestimated. The electron and proton temperatures, which could not be measured in this region by Voyager, are T ~ 2 eV at L ~ 3. Also, within this inner region the protons, because of a negative spacecraft potential, appear to be super-corotating. By enforcing the condition that protons and water group ions are co-moving we may be able to acquire an independent estimate of the spacecraft potential relative to that estimated when comparing ion-electron measurements. Using our estimates of plasma properties, we estimate the importance of the rotating plasma on the stress balance equation for the inner magnetosphere and corresponding portion of the ring current.

  14. Transfer Paths of Research Results to the Practice: Observations From the Receiving End

    NASA Astrophysics Data System (ADS)

    Findikakis, A. N.

    2005-12-01

    A non-scientific poll of fellow practicing professionals suggests that there is a range of opinions regarding the effectiveness of different ways of becoming acquainted with and using the results of academic research in their practice. Journal articles remain the dominant path for transferring research results to the profession, even though accessing them is becoming more difficult with time. Driven primarily by cost considerations personal and corporate subscriptions seem to be on the decline. Libraries are one of the first victims of cost cutting measures in the industry. Even though the availability of journal articles in electronic form facilitates their availability, their prices are prohibitive. This is especially true during when a professional is searching for a solution to a problem and may have to review several papers on the subject. One colleague suggested that the professional organizations and other publishers of research articles could learn from the experience of the music industry, by lowering the cost of downloading individual papers to something like a dollar per article, recovering thus their production costs through the increase in the volume of purchased articles. The posting on the internet of special reports and dissertations by research institutions is viewed as very useful by those working in practice. The distribution through the internet of reports by federal organizations conducting or sponsoring research, such as the U.S. Geological Survey and the U.S. Environmental Protection Agency is greatly appreciated by the practicing professionals. The use of leading researchers as consultants provides a direct path for bringing research results to the practice, but it is limited to a small number of cases where bringing in a consultant can be justified. Short courses are viewed as an effective way of familiarizing professionals with the latest research findings on specific subjects. The notes distributed in such courses are considered especially useful. Conferences and special symposia offer the opportunity to practicing professionals to find out what is the latest in different subject areas, but many view such meetings as having either a practical or a research character, and expressed the desire for more meetings that would bring together the practitioners and the researchers. Commercialization is another path for bringing research results to the practice, but is limited to areas where the size of the market for the commercial application of research findings makes it economically viable. The extent of the adoption of research findings in the practice varies across subjects. The results of research in subjects driven by pressing practical needs, such as remediation of contaminated groundwater or hydraulic testing have been passed quickly to the practice. Using the results of research in subjects such as fracture flow and stochastic hydrogeology seems more elusive.

  15. Satellite observation of lake ice as a climate indicator - Initial results from statewide monitoring in Wisconsin

    NASA Technical Reports Server (NTRS)

    Wynne, Randolph H.; Lillesand, Thomas M.

    1993-01-01

    The research reported herein focused on the general hypothesis that satellite remote sensing of large-area, long-term trends in lake ice phenology (formation and breakup) is a robust, integrated measure of regional and global climate change. To validate this hypothesis, we explored the use of data from the Advanced Very High Resolution Radiometer (AVHRR) to discriminate the presence and extent of lake ice during the winter of 1990-1991 on the 45 lakes and reservoirs in Wisconsin with a surface area greater than 1,000 hectares. Our results suggest both the feasibility of using the AVHRR to determine the date of lake ice breakup as well as the strong correlation (R= -0.87) of the date so derived with local surface-based temperature measurements. These results suggest the potential of using current and archival satellite data to monitor changes in the date of lake ice breakup as a means of detecting regional 'signals' of greenhouse warming.

  16. Preliminary results from the Orbiting Solar Observatory 8 - Observations of optically thin lines

    NASA Technical Reports Server (NTRS)

    Shine, R. A.; Roussel-Dupre, D.; Bruner, E. C., Jr.; Chipman, E. G.; Lites, B. W.; Rottman, G. J.; Athay, R. G.; White, O. R.

    1976-01-01

    The University of Colorado spectrometer aboard OSO 8 has measured the high temperature C IV resonance lines (at 1548 and 1551 A) and the Si IV resonance lines (at 1393 and 1402 A) formed in the solar chromosphere-corona transition region. Preliminary results include studies of mean profiles, a comparison of cell and network profiles, and the behavior of the lines at the extreme solar limb.

  17. Stellar Occultations by Transneptunian and Centaurs Objects: results from more than 10 observed events

    NASA Astrophysics Data System (ADS)

    Braga-Ribas, F.; Vieira-Martins, R.; Assafin, M.; Camargo, J. I. B.; Sicardy, B.; Ortiz, J. L.

    2014-10-01

    Transneptunian objects (TNOs) are small fossils of the Solar System orbiting beyond Neptune. We use stellar occultations to derive their size and shape. This work summarizes the main results derived, so far, from all detected TNO occultations (excluding Pluto system). We have developed a process, constructing astrometric star catalogues to make long-term reliable predictions (Camargo et al. 2014). Information about their physical properties are invaluable to the understanding of the dynamical evolution of the Solar System.

  18. Preliminary Results of Observations of Comets De Vico and Hyakutake by the Ulysses Comet Watch Network

    NASA Technical Reports Server (NTRS)

    Petersen, C. C.; Brandt, J. C.; Yi, Y.

    1996-01-01

    Cometary interactions with the solar wind allow us to use comets as probes of the inner regions of the heliosphere. During their close passage to the Sun, comets are exposed to different environments depending on their latitude. Until recently, characterizing these environments has been difficult because most spacecraft studying the sun have been confined to studying its mid-latitudes. A valuable source of information about the differing regimes of the solar wind is the joint ESA/NASA ULYSSES mission, which is the first spacecraft to explore the polar regions of the heliosphere. In 1995, ULYSSES' orbit covered a range of solar latitudes from -80 degrees to +80 degrees - an interval referred to as the 'fast latitude scan.' The Ulysses Comet Watch incorporates in-situ measurements during these periods by the ULYSSES spacecraft with images contributed by a world-wide network of observers (both amateur and professional). Bright comets whose paths come within 20 degrees solar latitude of the spacecraft are considered especially good targets for correlation between spacecraft data and plasma tail activity. Ulysses findings of interest to cometary plasma research are: Verification of global differences in solar wind properties (speed and density) at different solar latitudes. At polar latitudes - ranging from roughly +/-30 degrees to +/-80 degrees - the solar wind speed is about 750 kilometers/sec, and has a proton density (1 AU) around 3 cm(exp -3). Changes in properties are small and the heliospheric current sheet (HCS) is not seen. In the equatorial latitudes (roughly +30 to -30 degrees), the average solar wind speed is about 450 kilometers/sec, with an average proton density (at 1 AU) around 9 cm(exp -3). The HCS is seen and changes in properties can be large. An object, spacecraft or comet, at a given latitude, can be entirely in the polar, entirely in the equatorial, or can experience both - sort of a transition region.

  19. Nine-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Cosmological Parameter Results

    NASA Technical Reports Server (NTRS)

    Hinshaw, G.; Larson, D.; Komatsu, E.; Spergel, D. N.; Bennett, C. L.; Dunkley, J.; Nolta, M. R.; Halpern, M.; Hill, R. S.; Odegard, N.; Page, L.; Smith, K. L.; Weiland, J. L.; Gold, B.; Jarosik, N.; Kogut, A.; Limon, M.; Meyer, S. S.; Tucker, G. S.; Wollack, E.; Wright, E. L.

    2013-01-01

    We present cosmological parameter constraints based on the final nine-year Wilkinson Microwave Anisotropy Probe (WMAP) data, in conjunction with a number of additional cosmological data sets. The WMAP data alone, and in combination, continue to be remarkably well fit by a six-parameter Lambda-CDM model. When WMAP data are combined with measurements of the high-l cosmic microwave background anisotropy, the baryon acoustic oscillation scale, and the Hubble constant, the matter and energy densities Omega(sub b)h(exp 2), Omega(sub c)h(exp 2)and Omega(sub Lambda), are each determined to a precision of approx. 1.5%. The amplitude of the primordial spectrum is measured to within 3%, and there is now evidence for a tilt in the primordial spectrum at the 5 sigma level, confirming the first detection of tilt based on the five-year WMAP data. At the end of the WMAP mission, the nine-year data decrease the allowable volume of the six-dimensional Lambda-CDM parameter space by a factor of 68,000 relative to pre-WMAP measurements. We investigate a number of data combinations and show that their Lambda-CDM parameter fits are consistent. New limits on deviations from the six-parameter model are presented, for example: the fractional contribution of tensor modes is limited to r < 0.13 (95% CL); the spatial curvature parameter is limited to Omega(sub kappa) = (0.0027 (sub +0.0039) (sup -0.0038;) the summed mass of neutrinos is limited to Sigma M(sub nu) < 0.44 eV (95% CL); and the number of relativistic species is found to lie within N(sub eff) = 3.84 +/- 0+/-40, when the full data are analyzed. The joint constraint on N(sub eff) and the primordial helium abundance, Y(sub He), agrees with the prediction of standard big bang nucleosynthesis. We compare recent Planck measurements of the Sunyaev-Zel'dovich effect with our seven-year measurements, and show their mutual agreement. Our analysis of the polarization pattern around temperature extrema is updated. This confirms a fundamental prediction of the standard cosmological model and provides a striking illustration of acoustic oscillations and adiabatic initial conditions in the early universe.

  20. NINE-YEAR WILKINSON MICROWAVE ANISOTROPY PROBE (WMAP) OBSERVATIONS: COSMOLOGICAL PARAMETER RESULTS

    SciTech Connect

    Hinshaw, G.; Halpern, M.; Larson, D.; Bennett, C. L.; Weiland, J. L.; Komatsu, E.; Spergel, D. N.; Dunkley, J.; Nolta, M. R.; Hill, R. S.; Odegard, N.; Page, L.; Jarosik, N.; Smith, K. M.; Gold, B.; Kogut, A.; Wollack, E.; Meyer, S. S.; Tucker, G. S.; and others

    2013-10-01

    We present cosmological parameter constraints based on the final nine-year Wilkinson Microwave Anisotropy Probe (WMAP) data, in conjunction with a number of additional cosmological data sets. The WMAP data alone, and in combination, continue to be remarkably well fit by a six-parameter ?CDM model. When WMAP data are combined with measurements of the high-l cosmic microwave background anisotropy, the baryon acoustic oscillation scale, and the Hubble constant, the matter and energy densities, ? {sub b} h {sup 2}, ? {sub c} h {sup 2}, and ?{sub ?}, are each determined to a precision of ?1.5%. The amplitude of the primordial spectrum is measured to within 3%, and there is now evidence for a tilt in the primordial spectrum at the 5? level, confirming the first detection of tilt based on the five-year WMAP data. At the end of the WMAP mission, the nine-year data decrease the allowable volume of the six-dimensional ?CDM parameter space by a factor of 68,000 relative to pre-WMAP measurements. We investigate a number of data combinations and show that their ?CDM parameter fits are consistent. New limits on deviations from the six-parameter model are presented, for example: the fractional contribution of tensor modes is limited to r < 0.13 (95% CL); the spatial curvature parameter is limited to ?{sub k} = -0.0027{sup +0.0039}{sub -0.0038}; the summed mass of neutrinos is limited to ?m {sub ?} < 0.44 eV (95% CL); and the number of relativistic species is found to lie within N {sub eff} = 3.84 0.40, when the full data are analyzed. The joint constraint on N {sub eff} and the primordial helium abundance, Y {sub He}, agrees with the prediction of standard big bang nucleosynthesis. We compare recent Planck measurements of the Sunyaev-Zel'dovich effect with our seven-year measurements, and show their mutual agreement. Our analysis of the polarization pattern around temperature extrema is updated. This confirms a fundamental prediction of the standard cosmological model and provides a striking illustration of acoustic oscillations and adiabatic initial conditions in the early universe.

  1. Significant results from using earth observation satellites for mineral and energy resource exploration

    USGS Publications Warehouse

    Carter, William D.

    1981-01-01

    Launched in June 1978, Seasat operated for only 100 days, but successfully acquired much information over both sea and land. The collection of synthetic aperture radar (SAR) imagery and radar altimetry was particularly important to geologists. Although there are difficulties in processing and distributing these data in a timely manner, initial evaluations indicate that the radar imagery supplements Landsat data by increasing the spectral range and offering a different look angle. The radar altimeter provides accurate profiles over narrow strips of land (1 km wide) and has demonstrated usefulness in measuring icecap surfaces (Greenland, Iceland, and Antarctica). The Salar of Uyuni in southern Bolivia served as a calibration site for the altimeter and has enabled investigators to develop a land-based smoothing algorithm that is believed to increase the accuracy of the system to 10 cm. Data from the altimeter are currently being used to measure subsidence resulting from ground water withdrawal in the Phoenix-Tucson area.

  2. Instrumentation development for space debris optical observation system in Indonesia: Preliminary results

    NASA Astrophysics Data System (ADS)

    Dani, Tiar; Rachman, Abdul; Priyatikanto, Rhorom; Religia, Bahar

    2015-09-01

    An increasing number of space junk in orbit has raised their chances to fall in Indonesian region. So far, three debris of rocket bodies have been found in Bengkulu, Gorontalo and Lampung. LAPAN has successfully developed software for monitoring space debris that passes over Indonesia with an altitude below 200 km. To support the software-based system, the hardware-based system has been developed based on optical instruments. The system has been under development in early 2014 which consist of two systems: the telescopic system and wide field system. The telescopic system uses CCD cameras and a reflecting telescope with relatively high sensitivity. Wide field system uses DSLR cameras, binoculars and a combination of CCD with DSLR Lens. Methods and preliminary results of the systems will be presented.

  3. Artificial cochlea and acoustic black hole travelling waves observation: Model and experimental results

    NASA Astrophysics Data System (ADS)

    Foucaud, Simon; Michon, Guilhem; Gourinat, Yves; Pelat, Adrien; Gautier, Franois

    2014-07-01

    An inhomogeneous fluid structure waveguide reproducing passive behaviour of the inner ear is modelled with the help of the Wentzel-Kramers-Brillouin method. A physical setup is designed and built. Experimental results are compared with a good correlation to theoretical ones. The experimental setup is a varying width plate immersed in fluid and terminated with an acoustic black hole. The varying width plate provides a spatial repartition of the vibration depending on the excitation frequency. The acoustic black hole is made by decreasing the plate's thickness with a quadratic profile and by covering this region with a thin film of viscoelastic material. Such a termination attenuates the flexural wave reflection at the end of the waveguide, turning standing waves into travelling waves.

  4. Geomorphic expression of strike-slip faults: field observations vs. analog experiments: preliminary results

    NASA Astrophysics Data System (ADS)

    Hsieh, S. Y.; Neubauer, F.; Genser, J.

    2012-04-01

    The aim of this project is to study the surface expression of strike-slip faults with main aim to find rules how these structures can be extrapolated to depth. In the first step, several basic properties of the fault architecture are in focus: (1) Is it possible to define the fault architecture by studying surface structures of the damage zone vs. the fault core, particularly the width of the damage zone? (2) Which second order structures define the damage zone of strike-slip faults, and how relate these to such reported in basement fault strike-slip analog experiments? (3) Beside classical fault bend structures, is there a systematic along-strike variation of the damage zone width and to which properties relates the variation of the damage zone width. We study the above mentioned properties on the dextral Altyn fault, which is one of the largest strike-slip on Earth with the advantage to have developed in a fully arid climate. The Altyn fault includes a ca. 250 to 600 m wide fault valley, usually with the trace of actual fault in its center. The fault valley is confined by basement highs, from which alluvial fans develop towards the center of the fault valley. The active fault trace is marked by small scale pressure ridges and offset of alluvial fans. The fault valley confining basement highs are several kilometer long and ca. 0.5 to 1 km wide and confined by rotated dextral anti-Riedel faults and internally structured by a regular fracture pattern. Dextral anti-Riedel faults are often cut by Riedel faults. Consequently, the Altyn fault comprises a several km wide damage zone. The fault core zone is a barrier to fluid flow, and the few springs of the region are located on the margin of the fault valley implying the fractured basement highs as the reservoir. Consequently, the southern Silk Road was using the Altyn fault valley. The preliminary data show that two or more orders of structures exist. Small-scale develop during a single earthquake. These finally accumulate to a several 100 m wide fault core, which is in part exposed at surface to arid climate and a km wide damage zone. The basic structures of analog experiments can be well transferred to nature, although along strike changes are common due to fault bending and fracture failure of country rocks.

  5. Spatial and Temporal Distribution of Cloud Properties Observed by MODIS: Preliminary Level-3 Results from the Collection 5 Reprocessing

    NASA Technical Reports Server (NTRS)

    King, Michael D.; Platnick, Steven; Hubanks, Paul; Pincus, Robert

    2006-01-01

    The Moderate Resolution Imaging Spectroradiometer (MODIS) was developed by NASA and launched onboard the Terra spacecraft on December 18, 1999 and Aqua spacecraft on May 4, 2002. It achieved its final orbit and began Earth observations on February 24, 2000 for Terra and June 24, 2002 for Aqua. A comprehensive set of operational algorithms for the retrieval of cloud physical and optical properties (optical thickness, effective particle radius, water path, thermodynamic phase) have recently been updated and are being used in the new "Collection 5" processing stream being produced by the MODIS Adaptive Processing System (MODAPS) at NASA GSFC. All Terra and Aqua data are undergoing Collection 5 reprocessing with an expected completion date by the end of 2006. The archived products from these algorithms include 1 km pixel-level (Level-2) and global gridded Level-3 products. The cloud products have applications in climate change studies, climate modeling, numerical weather prediction, as well as fundamental atmospheric research. In this talk, we will summarize the available Level-3 cloud properties and their associated statistical data sets, and show preliminary Terra and Aqua results from the available Collection 5 reprocessing effort. Anticipated results include the latitudinal distribution of cloud optical and radiative properties for both liquid water and ice clouds, as well as joint histograms of cloud optical thickness and effective radius for selected geographical locations around the world.

  6. Epidemiology of multiple sclerosis: results from a large observational study in the UK.

    PubMed

    Jick, Susan S; Li, L; Falcone, G J; Vassilev, Z P; Wallander, M-A

    2015-09-01

    Multiple sclerosis (MS) progression to mortality may not be solely determined by the underlying autoimmune process. We conducted a study in a large cohort of MS patients with the aim of describing characteristics of MS patients and identification of predictors for all-cause mortality in this patient group. We performed a retrospective analysis of primary care data from the UK Clinical Practice Research Datalink. Incident MS cases diagnosed between 1993 and 2006 were identified and validated using electronic and original medical records. Patients were followed to identify deaths; hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using Cox proportional regression with age as time-scale. In total, 1713 incident MS cases were identified. Following MS diagnosis, frequent comorbidities were infections (80%), and depression (46%). Adjusted HRs (95% CIs) for all-cause mortality were: 2.0 (1.2-3.4) for current smoking; 7.6 (3.2-17.7) for alcohol abuse; 2.7 (1.6-4.5) for pneumonia and influenza; 4.1 (2.7-6.3) for urinary tract infections; 2.2 (1.2-4.2) for heart disease and 4.9 (2.9-8.0) for cancer. Our results suggest that MS survival is influenced not only by the underlying autoimmune process, but also by patient comorbidities and lifestyle factors. PMID:26067217

  7. College football, elections, and false-positive results in observational research.

    PubMed

    Fowler, Anthony; Montagnes, B Pablo

    2015-11-10

    A recent, widely cited study [Healy AJ, Malhotra N, Mo CH (2010) Proc Natl Acad Sci USA 107(29):12804-12809] finds that college football games influence voting behavior. Victories within 2 weeks of an election reportedly increase the success of the incumbent party in presidential, senatorial, and gubernatorial elections in the home county of the team. We reassess the evidence and conclude that there is likely no such effect, despite the fact that Healy et al. followed the best practices in social science and used a credible research design. Multiple independent sources of evidence suggest that the original finding was spurious-reflecting bad luck for researchers rather than a shortcoming of American voters. We fail to estimate the same effect when we leverage situations where multiple elections with differing incumbent parties occur in the same county and year. We also find that the purported effect of college football games is stronger in counties where people are less interested in college football, just as strong when the incumbent candidate does not run for reelection, and just as strong in other parts of the state outside the home county of the team. Lastly, we detect no effect of National Football League games on elections, despite their greater popularity. We conclude with recommendations for evaluating surprising research findings and avoiding similar false-positive results. PMID:26504202

  8. Spatiotemporal ecohydrological patterns and processes in temperate uplands: linking field observations and model results

    NASA Astrophysics Data System (ADS)

    Dodd, N. H.; Baird, A. J.; Wainwright, J.; Dunn, S. M.

    2011-12-01

    There are obvious surface expressions - in terms of vegetation patterning - of ecohydrological feedbacks on dryland and peatland hillslopes. Much less is known about subsurface ecohydrological patterns, and whether or not they 'map onto' surface patterns. Likewise, few attempts have been made to investigate how such ecohydrological patterns affect whole-hillslope hydrological behaviour or how widespread they are in non-dryland and non-peatland hillslopes. In this study we investigate surface and near- surface patterning in temperate hillslopes, which to date have been the focus of much hydrological work but little ecohydrological work. In particular, we consider the extent to which the direct and the indirect effects of past and present plant assemblages on local and whole-hillslope soil moisture conditions may contribute to patterning. We have conducted a field study of two temperate upland hillslopes in Northern Scotland, UK, on one of which human intervention plays a major part in shaping the landscape. Repeat measurements have been made of near- surface soil-moisture content, taken at lag distances of 0.25 m to 20 m, under different antecedent hydrological conditions together with characterisation of plant assemblages at the same points through both ground-based vegetation surveys of 1 m 1 m plots and kite aerial photography (KAP) of > 20 m2 plots. Results from this have indicated that changes in ecohydrological patterns can occur over small spatial scales (< 1 m2) and short time scales (< 1 day). Comparison of values of near-surface soil moisture content with topographic wetness indices, calculated using 1 -m resolution topographic data collected in the field, has highlighted that topography does not explain all of the spatial variation in soil moisture content at this scale. KAP images allowed detection of vegetation patterns not obvious from the ground. Comparison of KAP images and historic aerial photographs has highlighted the persistence of vegetation patterns over time at both sites, and that the current structure of the landscape is clearly related to current and past vegetation management practices. Evidence of sustained patterning under relatively steady environmental conditions has prompted us to consider how internal system dynamics such as competition and facilitation between different plant assemblages, and persistence of ecological memory at a range of timescales may lead to a range of ecohydrological behaviours at the scale of whole hillslopes. To help conceptualize ways in which patterning may arise, we have built a two-dimensional cellular automata-type model in which local interactions between biotic and abiotic components have the potential to lead to emergence of larger-scale patterns within the model landscape. Results from the field study have been used to gauge how well temperate hillslope ecohydrological dynamics are represented in our model, and to check that local neighbourhood patterns in the model outputs resemble real-world patterning. Key words: temperate upland ecohydrology, plant assemblage dynamics, ecological memory, kite aerial photography, cellular automata.

  9. Lithospheric geometries revealed through electromagnetic imaging: SAMTEX (Southern Africa MagnetoTelluric Experiment) observations and results

    NASA Astrophysics Data System (ADS)

    Jones, A. G.; Muller, M. R.; Evans, R. L.; Miensopust, M. P.; Khoza, D. T.; Samtex Team

    2011-12-01

    The Southern African Magnetotelluric Experiment (SAMTEX) is imaging the properties and geometries of the lithosphere below southern Africa to depths of 200+ km. Electrical conductivity is highly sensitive to ambient temperature, and to the presence of an interconnected conducting phase, such as a solid phase like graphite or sulphides, a fluid phase like partial melt, or bound water through hydrogen diffusion. Thus, primary geometrical information can be readily obtained from lithospheric-scale MT experiments about the three-dimensional variation in conductivity that can be related to formation and deformation processes. One important piece of information easily obtained from MT data is the depth to the lithosphere-asthenosphere boundary (LAB), due to the sensitivity of conductivity to small fractions (<1%) of partial melt and/or of some hundreds of ppm of bound water. SAMTEX measurements have been made at a total of more than 750 MT sites over an area in excess of a million square kilometres, making it by far the largest-ever regional MT project undertaken. One of the most significant results from SAMTEX is the mapping of the LAB beneath the Archean cratons and bounding mobile belts of Southern Africa, particularly of the previously unknown regions of Namibia and Botswana. The LAB is shallow (150 km) beneath the mobile belts, deep (250 km) in the centres of the cratons, and transitional at the edges. Diamondiferous kimberlites are located primarily where lithosphere is transitional in thickness, or where there is a change in its anisotropy properties, both of which are craton edge effects. The electrical properties of the continental mantle derived from SAMTEX data can be compared with seismic ones derived from data from the South African Seismic Experiment (SASE) of the Kaapvaal Project. Generally there is very good predictive linear agreement between seismic velocity and log(conductivity), indicative of both being influenced by the same bulk property factors, such as temperature, Mg# and composition.

  10. Prognostic Value of Stress Myocardial Perfusion Positron Emission Tomography: Results From A Multicenter Observational Registry

    PubMed Central

    Dorbala, Sharmila; Di Carli, Marcelo F.; Beanlands, Rob S.; Merhige, Michael E.; Williams, Brent A.; Veledar, Emir; Chow, Benjamin JW.; Min, James K.; Pencina, Michael J.; Berman, Daniel S.; Shaw, Leslee J.

    2012-01-01

    Objectives The primary objective of this multicenter registry was to study the prognostic value of PET MPI and the improved classification of risk in a large cohort of patients with suspected or known coronary artery disease (CAD). Background Limited prognostic data are available for myocardial perfusion imaging (MPI) with positron emission tomography (PET). Methods 7,061 patients from 4 centers underwent a clinically indicated rest/stress rubidium-82 PET MPI with a median follow-up of 2.2 years. The primary outcome of this study was cardiac-death (169 patients) and the secondary outcome was all-cause death (570 patients). Net reclassification improvement (NRI) and integrated discrimination (IDI) analyses were performed. Results Risk-adjusted hazard of cardiac-death increased with each 10% abnormal myocardium with mildly, moderately or severely abnormal stress PET [hazard ratio 2.3 (95% CI 1.43.8, P=0.001), 4.2 (95% CI 2.37.5, P<0.001), and 4.9 (95% CI 2.59.6, P <0.0001), respectively, normal MPI: referent]. Addition of %myocardium ischemic and scarred to clinical information (age, female sex, body mass index, history of hypertension, diabetes, dyslipidemia, smoking, angina, betablocker use, prior revascularization and rest heart rate) improved the model performance [C-statistic 0.805 (95% CI, 0.7720.838) to 0.839 (95% CI, 0.8090.869)] and risk reclassification for cardiac-death [NRI 0.116 (95% CI 0.0210.210)] with smaller improvements in risk assessment for all-cause death. Conclusions In patients with known or suspected CAD, the extent and severity of ischemia and scar on PET MPI provide powerful and incremental risk estimates of cardiac-death and all-cause death compared to traditional coronary risk factors. PMID:23219297

  11. Five-Year Wilkinson Microwave Anisotropy Probe Observations: Data Processing, Sky Maps, and Basic Results

    NASA Technical Reports Server (NTRS)

    Hinshaw, G.; Weiland, J. L.; Hill, R. S.; Odegard, N.; Larson, D.; Bennett, C. L.; Dunkley, J.; Gold, B.; Greason, M. R.; Jarosik, N.; Komatsu, E.; Nolta, M. R.; Page, L.; Spergel, D. N.; Wollack, E.; Halpern, M.; Kogut, A.; Limon, M.; Meyer, S. S.; Tucker, G. S.; Wright, E. L.

    2010-01-01

    We present new full-sky temperature and polarization maps in five frequency bands from 23 to 94 GHz, based on data from the first five years of the Wilkinson Microwave Anisotropy Probe (WMAP) sky survey. The new maps are consistent with previous maps and are more sensitive. The five-year maps incorporate several improvements in data processing made possible by the additional years of data and by a more complete analysis of the instrument calibration and in-flight beam response. We present several new tests for systematic errors in the polarization data and conclude that W-band polarization data is not yet suitable for cosmological studies, but we suggest directions for further study. We do find that Ka-band data is suitable for use; in conjunction with the additional years of data, the addition of Ka band to the previously used Q- and V-band channels significantly reduces the uncertainty in the optical depth parameter, tau. Further scientific results from the five-year data analysis are presented in six companion papers and are summarized in Section 7 of this paper. With the five-year WMAP data, we detect no convincing deviations from the minimal six-parameter ACDM model: a flat universe dominated by a cosmological constant, with adiabatic and nearly scale-invariant Gaussian fluctuations. Using WMAP data combined with measurements of Type Ia supernovae and Baryon Acoustic Oscillations in the galaxy distribution, we find (68% CL uncertainties): OMEGA(sub b)h(sup 2) = 0.02267(sup +0.00058)(sub -0.00059), OMEGA(sub c)h(sup 2) = 0.1131 plus or minus 0.0034, OMEGA(sub logical and) = 0.726 plus or minus 0.015, ns = .960 plus or minus 0.013, tau = 0.84 plus or minus 0.016, and DELTA(sup 2)(sub R) = (22.445 plus or minus 0.096) x 10(exp -9) at k = 0.002 Mpc(exp -1). From these we derive sigma(sub 8) = 0.812 plus or minus 0.026, H(sub 0) = 70.5 plus or minus 1.3 kilometers per second Mpc(exp -1), OMEGA(sub b) = 0.0456 plus or minus 0.0015, OMEGA(sub c) = .228 plus or minus 0.013, OMEGA(sub m)h(sup 2) = 0.1358(sup +0.0037)(sub -0.0036), z reion = 10.9 plus or minus 1.4, and t(sub 0) = 13.72 plus or minus 0.12 Gyr. The new limit on the tensor-to-scalar ration is r less than 0.22 (95% CL), while the evidence for a running spectral index is insignificant, dn(sub s)/d ln k = -0.028 plus or minus 0.020 (68% CL). We obtain tight, simultaneous limits on the (constant) dark energy equation of state and the spatial curvature of the universe: -0.14 less than 1 + w less than 0.12 (95% CL) and -0.0179 less than OMEGA(sub k) less than 0.0081 (95% CL). The number of relativistic degrees of freedom, expressed in units of the effective number of neutrino species, is found to be N(sub eff) = 4.4 plus or minus 1.5 (69% CL), consistent with the standard value of 3.04. Models with N(sub eff) = 0 are disfavored at greater than 99% confidence. Finally, new limits on physically motivated primordial non-Gaussianity parameters are -9 less than f(sup local)(sub NL) less than 111 (95% CL) and -151 less than f(sup equal)(sub NL) less than 253 (95% CL) for the local and equilateral models, respectively.

  12. Initial results of VLF Campaign observation with High-resolution Aurora Imaging Network (VLF-Chain) over Canada

    NASA Astrophysics Data System (ADS)

    Shiokawa, Kazuo

    2012-07-01

    Whistler-mode waves in the VLF/ELF frequency range interact with high-energy (~10 keV) electrons to cause diffuse and pulsating auroras, and with MeV electrons in the radiation belts. However, simultaneous high-time resolution measurements of aurora and these waves have previously not been done sufficiently. We made a campaign observation of such high-time resolution measurements at Athabasca (54.72N, 246.69E, MLAT=61.3) and Fort Vermillion (58.38N, 243.99E, MLAT=64.5) using two loop antennas and several auroral cameras for February 16-26, 2012. The loop antennas at both stations measure east-west and north-south magnetic field variations with a sampling rate of 100 kHz. The panchromatic all-sky cameras at both stations measure auroras with a sampling rate of 30 Hz. The sampling timings of both instruments are corrected by GPS receivers. In addition we installed an oblique looking narrow-FoV EMCCD camera at Athabasca with a sampling rate of 100 Hz, to measure height variation of pulsating aurora. At Athabasca, routine measurements by an induction magnetometer, a proton photometer, an all-sky airglow imager, LF standard wave receiver, were also carried out. We also tried to compare these observations with satellite measurements by REIMEI, THEMIS, NOAA, and DMSP. In this presentation we will show initial results obtained from this comprehensive campaign of aurora and radio wave measurements at subauroral latitudes.

  13. Results.

    ERIC Educational Resources Information Center

    Zemsky, Robert; Shaman, Susan; Shapiro, Daniel B.

    2001-01-01

    Describes the Collegiate Results Instrument (CRI), which measures a range of collegiate outcomes for alumni 6 years after graduation. The CRI was designed to target alumni from institutions across market segments and assess their values, abilities, work skills, occupations, and pursuit of lifelong learning. (EV)

  14. Observational Results using BTFI

    NASA Astrophysics Data System (ADS)

    Quint, B.; Mendes de Oliveira, C.

    2014-10-01

    We present here an overview of a new tunable filter instrument for the SOAR telescope. The Brazilian Tunable Filter Imager (BTFI) is a highly versatile new technology to be used both in seeing-limited mode and at higher spatial fidelity using SAM Ground-Layer Adaptive Optics facility (SOAR Adaptive Module) which is being deployed at the SOAR telescope. It presents important new science capabilities for the SOAR astronomical community, from studies of the centers of nearby galaxies and the insterstellar medium to statistical cosmological investigations.

  15. Atmosphere-Ionosphere Response to the M9 Tohoku Earthquake Revealed by Joined Satellite and Ground Observations. Preliminary Results

    NASA Technical Reports Server (NTRS)

    Ouzounov, Dimitar; Pulinets, Sergey; Romanov, Alexey; Tsybulya, Konstantin; Davidenko, Dimitri; Kafatos, Menas; Taylor, Patrick

    2011-01-01

    The recent M9 Tohoku Japan earthquake of March 11, 2011 was the largest recorded earthquake ever to hit this nation. We retrospectively analyzed the temporal and spatial variations of four different physical parameters - outgoing long wave radiation (OLR), GPS/TEC, Low-Earth orbit tomography and critical frequency foF2. These changes characterize the state of the atmosphere and ionosphere several days before the onset of this earthquake. Our first results show that on March 8th a rapid increase of emitted infrared radiation was observed from the satellite data and an anomaly developed near the epicenter. The GPS/TEC data indicate an increase and variation in electron density reaching a maximum value on March 8. Starting on this day in the lower ionospheric there was also confirmed an abnormal TEC variation over the epicenter. From March 3-11 a large increase in electron concentration was recorded at all four Japanese ground based ionosondes, which return to normal after the main earthquake. We found a positive correlation between the atmospheric and ionospheric anomalies and the Tohoku earthquake. This study may lead to a better understanding of the response of the atmosphere/ionosphere to the Great Tohoku earthquake.

  16. A mammographic mass CAD system incorporating features from shape, fractal, and channelized Hotelling observer measurements: preliminary results

    NASA Astrophysics Data System (ADS)

    Catarious, David M., Jr.; Baydush, Alan H.; Abbey, Craig K.; Floyd, Carey E., Jr.

    2003-05-01

    In this paper, we present preliminary results from a highly sensitive and specific CAD system for mammographic masses. For false positive reduction, the system incorporated features derived from shape, fractal, and channelized Hotelling observer (CHO) measurements. The database for this study consisted of 80 craniocaudal mammograms randomly extracted from USF's digital database for screening mammography. The database contained 49 mass findings (24 malignant, 25 benign). To detect initial mass candidates, a difference of Gaussians (DOG) filter was applied through normalized cross correlation. Suspicious regions were localized in the filtered images via multi-level thresholding. Features extracted from the regions included shape, fractal dimension, and the output from a Laguerre-Gauss (LG) CHO. Influential features were identified via feature selection techniques. The regions were classified with a linear classifier using leave-one-out training/testing. The DOG filter achieved a sensitivity of 88% (23/24 malignant, 20/25 benign). Using the selected features, the false positives per image dropped from ~20 to ~5 with no loss in sensitivity. This preliminary investigation of combining multi-level thresholded DOG-filtered images with shape, fractal, and LG-CHO features shows great promise as a mass detector. Future work will include the addition of more texture and mass-boundary descriptive features as well as further exploration of the LG-CHO.

  17. Low-latitude field-aligned irregularities observed in the E region with the Piura VHF radar: First results

    NASA Astrophysics Data System (ADS)

    Woodman, Ronald F.; Chau, Jorge L.; Aquino, Fredy; Rodriguez, Rodolfo R.; Flores, Luis A.

    1999-07-01

    We have used the Piura VHF radar (512'S, 8038'W, 7.5N geomagnetic latitude, just outside the magnetic equator) in northern Peru to gather echoes from 3-m E region field-aligned irregularities. We present statistical results of these echoes: percentage of occurrence and histograms of radial velocities and spectral widths, obtained with a 15-day data set gathered in 1996. These E region echoes are confined to 95- to 120-km altitude and present spectral characteristics similar to equatorial electrojet (EEJ) echoes generated by a gradient drift instability, i.e., type 2. However, they appear mainly at nighttime and early morning (1800-0800 LT) and therefore do not present a temporal similarity to EEJ echoes. Moreover, we observe the existence of two well-defined types of echoes: (1) lower E region echoes (95-105 km) and upper E region echoes (105-120 km). Both regions show different spectral and temporal characteristics. It is difficult to determine at this point the physical mechanisms responsible for the formation of the irregularities without measurements of E fields and density gradients, which we plan to do in a future experiment.

  18. Evidencing the transition from Mode I cracking to dilation banding: Results from physical experiments with fractographic observations

    NASA Astrophysics Data System (ADS)

    Nguyen, S.; Chemenda, A.; Petit, J.; Ambre, J.; Geo-Fracnet-Goazur

    2010-12-01

    The mechanism of quasi-brittle fracture/rupture remains one of the central problems in different domains of material science/mechanics including geomechanics. There are basically two approaches to this problem. One is the fracture mechanics dealing with stability conditions of cracks characterized by a strong stress concentration at the tips causing crack propagation. The other approach is the formation of deformation localization bands as constitutive instabilities, whose onset in quasi-brittle rocks can be considered as corresponding to the inception of rupture. We investigate the conditions of applicability of these end-member approaches and show a continuous transition from one to another with an increase in the confining pressure P in the experimental extension tests on a synthetic physical rock analogue (granular, frictional, cohesive and dilatant) material GRAM1. Discontinuities/fractures perpendicular to the least (axial) stress ?3 were generated in GRAM1 samples. These fractures form dynamically and are of two types defined by the mean stress ? or P. When ? is very small, the fractures form through mode I cracking with ?3 equal to the material tensile strength. The fracture walls have smooth surfaces in this case. Increase in ? causes increase in ?3 at fracturing, which becomes less negative and reaches small positive (compression) values, while the failure still occurs along a discontinuity perpendicular to ?3. Thus, the discontinuities generated starting from a certain ? value cannot be mode I fractures. Increase in ? also results in changes in the relief of the surfaces of discontinuities after their postmortem opening (separation of the walls): the surfaces become rougher, with the topography features forming faint/delicate plumose patterns very similar to those on the geological joint walls. SEM observations of the unopened discontinuities show that they represent several grain sizes-thick bands of a material which underwent a heterogeneous decohesion and volume/porosity increase. This suggests a dilatancy within bands. After opening they become fractures with plumose fractography. As indicated, these fractures could not be formed through the mode I mechanism. The true formation mechanism is not completely clear, but it is suggested that it represents a running constitutive instability in the form of dilation banding (with further ? increase the bands become inclined to ?1, i.e., shear; inclination angle grows with ?). The morphological similarity between the experimentally generated plumose-surface fractures and natural joints surfaces is shown. On the other hand, MEB observations evidence a textural similarity between the experimental bands and some natural unopened incipient joints found in fine grained rocks. It is proposed that propagating dilation bands could be an important mechanism for the generation of natural joints.

  19. Development of supermirror hard x-ray telescope and the results of first observation flight of InFOCuS flight observation

    NASA Astrophysics Data System (ADS)

    Ogasaka, Yasushi; Tamura, Keisuke; Okajima, Takashi; Tawara, Yuzuru; Yamashita, Koujun; Furuzawa, Akihiro; Haga, Kazutoshi; Ichimaru, Satoshi; Takahashi, Seiji; Fukuda, Shinichi; Kito, Hideo; Goto, Arifumi; Kato, Seima; Satake, Hiroyuki; Nomoto, Ken'ichi; Hamada, Noriyuki; Serlemitsos, Peter J.; Tueller, Jack; Soong, Yang; Chan, Kai-Wing; Owens, Scott M.; Berendse, Fred; Krimm, Hans; Baumgartner, Wayne; Barthelmy, Scott D.; Kunieda, Hideyo; Misaki, Kazutami; Shibata, Ryo; Mori, Hideyuki; Itoh, Kei; Namba, Yoshiharu

    2003-03-01

    The development of hard X-ray focusing optics is widely recognized as one of key technologies for future X-ray observatory missions such as NeXT(Japan), Constellation-X(US) and possibly XEUS(Europe). We have developed hard X-ray telescope employing depth-graded multilayers, so-called supermirrors. Its benefit is to reflect hard X-rays by Bragg reflection at incidence angles larger than the critical angle of total external reflection. We are now continuously fabricating platinum-carbon(Pt/C) supermirror reflectors for hard X-ray observations. In this paper we focus on our development of the hard X-ray telescope for the first balloon flight observation (InFOCuS) and its results. InFOCuS is an international balloon-borne hard X-ray observation experiment initiated by NASA/GSFC. InFOCuS hard X-ray telescope have been jointly developed by Nagoya University and GSFC. The telescope is conical approximation of Wolter-I optics with 8m focal length and 40cm diameter. It consists of 255 nested ultra-thin reflector pairs with incidence angles of 0.10 to 0.36deg. Reflectors are coated with Pt/C supermirrors with periodic length of 2.9 to 10nm and bi-layer number of 25 to 60, depending on incidence angles. The effective area and imaging quality are expected as 100 cm2 at 30 keV and 2 arcmin in half power diameter, respectively. The InFOCuS experiment was launched on July 5, 2001, from National Scientific Balloon Facility in Texas, USA. We successfully observed Cyg X-1, chosen for a calibration target, in 20-40keV energy band. We are planning to carry out next flight for scientific observations as soon as additional telescopes, detectors, and upgraded gondola system are implemented.

  20. Preliminary results on the apparent size of the sources of type III bursts observed at low frequencies

    NASA Technical Reports Server (NTRS)

    Alvarez, H.

    1976-01-01

    We present preliminary results on the apparent angular size of the sources of four type III bursts observed between 3500 and 50 kHz from the IMP-6 spacecraft. The observations were made with a dipole rotating in the plane of the ecliptic where the sources are assumed to be. The apparent angular sizes obtained are unexpectedly large. We discuss different explanations for the results. It seems that the scattering of radio waves by electron density inhomogeneities is the most likely cause. We report a temporal increase of the apparent angular size of the source during the burst lifetime for some bursts. From its characteristics it appears to be a real effect.

  1. Observations of the solar corona in polarized white light during the total solar eclipse of February 16, 1980 Preliminary results

    NASA Astrophysics Data System (ADS)

    Clette, F.; Cugnon, P.; Koeckelenbergh, A.

    1985-07-01

    Photographic observations of the corona were made by a Belgian expedition to Kenya during the eclipse of 1980, February 16, using a polaroid filter oriented in three directions 60 apart. The preliminary results of the reduced data are presented here; these results consist in the analysis of the three following parameters: total intensity, degree of polarization, direction of the electric vector. The local variation of these parameters reveals, among other features, a deep coronal hole at the south pole and peculiar streamer (P.A. 280) associated to a transient, (the so-called "tennis racket") also observed by other teams, and a density enhancement at P.A. 200, possibly associated with a transient observed with the K-coronameter of the High Altitude Observatory 12 hr before the eclipse.

  2. [Results from the X-ray and Optical Follow-up Observations of the Swift BAT AGN Survey

    NASA Technical Reports Server (NTRS)

    Mushotzky, R.

    2008-01-01

    I will present results from the x-ray and optical follow-up observations of the Swift BAT ACN survey. I will discuss the nature of obscuration in these objects, the relationship to optical properties and the change of properties with luminosity and galaxy type and how they will influence the design of XO.

  3. Preliminary Results From Observing The Fast Stardust Sample Return Capsule Entry In Earth's Atmosphere On January 15, 2006.

    NASA Astrophysics Data System (ADS)

    Jenniskens, P.; Jordan, D.; Kontinos, D.; Wright, M.; Olejniczak, J.; Raiche, G.; Wercinski, P.; Schilling, E.; Taylor, M.; Rairden, R.; Stenbaek-Nielsen, H.; McHarg, M. G.; Abe, S.; Winter, M.

    2006-08-01

    In order for NASA's Stardust mission to return a comet sample to Earth, the probe was put in an orbit similar to that of Near Earth Asteroids. As a result, the reentry in Earth's atmosphere on January 15, 2006, was the fastest entry ever for a NASA spacecraft, with a speed of 12.8 km/s, similar to that of natural fireballs. A new thermal protection material, PICA, was used to protect the sample, a material that may have a future as thermal protection for the Crew Return Vehicle or for future planetary missions. An airborne and ground-based observing campaign, the "Stardust Hyperseed MAC", was organized to observe the reentry under good observing conditions, with spectroscopic and imaging techniques commonly used for meteor observations (http:// reentry.arc.nasa.gov). A spectacular video of the reentry was obtained. The spectroscopic observations measure how much light was generated in the shock wave, how that radiation added to heating the surface, how the PICA ablated as a function of altitude, and how the carbon reacted with the shock wave to form CN, a possible marker of prebiotic chemistry in natural meteors. In addition, the observations measured a transient signal of zinc and potassium early in the trajectory, from the ablation of a white paint layer that had been applied to the heat shield for thermal control. Implications for sample return and the exploration of atmospheres in future planetary missions will be discussed.

  4. Binaries with a ? Scuti Component: Results from a Long-Term Observational Survey, Updated Catalog, and Future Prospects

    NASA Astrophysics Data System (ADS)

    Liakos, A.; Niarchos, P.

    2015-07-01

    Results are presented from a six-year systematic observational survey of candidate eclipsing binaries with a ? Sct component. More than one hundred systems with component(s) of spectral type A-F were observed in order to check for possible pulsational behavior. Some 14% (13 cases) among the currently known systems of this class were confirmed. We present an updated list of all currently known ? Sct systems in eclipsing binaries based on all available information from the literature. Possible correlations between their pulsational and binary properties are discussed.

  5. Comparison of satellite NO2 results with mobile MAX-DOAS observations and CHIMERE model simulations for Paris

    NASA Astrophysics Data System (ADS)

    Shaiganfar, Reza; Beirle, Steffen; Petetin, Herve; Zhang, Qiji; Beekmann, Matthias; Wagner, Thomas

    2013-04-01

    Megacities are localized, heterogeneous and variable sources of various air pollutants, having great impact on air quality and ultimately on climate. Within the European project MEGAPOLI we characterise and quantify the pollution levels and emissions using spectroscopic observations from satellite and ground based instruments mounted on a car. The mobile observations are conducted on circles with different radii around megacities. From the satellite observations the link from local to regional and global scales can be made. Especially the impact of important sources like megacities on the surrounding areas and also over longer distances can be studied. The combination with the mobile measurements adds information about the heterogeneity within a satellite pixel and the diurnal cycle, which are not well captured from satellite observations. The CHIMERE model is used to produce daily 3D fields of different trace gases, ozone and aerosols. We compare the CHIMERE model with mobile MAX-DOAS and OMI satellite observations. The mobile measurements are also used for validation of the satellite observations. We compare the tropospheric NO2 from OMI (TEMIS) with our mobile MAX-DOAS vertical column densities (VCDs). In general good agreement of the spatial patterns was found between differet data sets. However, the mobile MAX-DOAS measurements usually showed much finer details of the horizontal distributions than the satellite and model data. Also differences in the absolute values were found: The Chimere data are17x% lower and 45% lower than the mobile MAX-DOAS data in summer and winter, respectively. The satellite data are about 50 % lower than mobile MAX-DOAS.

  6. Palomar and Table Mountain Observations of 9P/Tempel 1 during the Deep Impact Encounter: First Results

    NASA Technical Reports Server (NTRS)

    Bauer, James M.; Weissman, Paul R.; Choi, Young-Jun; Troy, Mitchell; Young, James W.; Lisse, Carey M.; Dekany, Richard; Hanner, Martha S.; Buratti, Bonnie J.

    2007-01-01

    We present the first results of the Palomar Adaptive Optics observations taken during the Deep Impact encounter with 9P/Tempel 1 in July 2005. We have combined the Palomar near-IR imaging data with our visual wavelength images obtained simultaneously at JPL's Table Mountain Observatory to cover the total wavelength range from 0.4 to 2.3 micrometers in the B, V, R, I, J, H, and K filter bands, spanning the dates from 2005 July 03-07.We also include in our overall analysis images taken on the pre-encounter dates of June 1 and June 15, 2005. The broad wavelength range of our observations, along with high temporal resolution, near-IR sensitivity, and spatial resolution of our imaging, have enabled us to place constraints on the temperature of the impact flash and incandescent plume of greater than 700 K, and to provide mean dust velocities of order 197 +/- 16 m/s approximately 1.25 h after impact derived from our 1.64 micro observations. Our ejected dust mass estimates, as derived from our near-IR observations, are an order of magnitude less than those previously reported for visual wavelength observations.

  7. Observations and Parameterizations of Particle Size Distributions in Deep Tropical Cirrus and Stratiform Precipitation Clouds: Results from In-Situ Observations in TRMM Field Campaigns

    NASA Technical Reports Server (NTRS)

    Heymsfield, Andrew J.; Bansemer, Aaron; Field, Paul R.; Durden, Stephen L.; Stith, Jeffrey L.; Dye, James E.; Hall, William; Grainger, Cedric A.

    2002-01-01

    In this study, we report on the evolution of particle size distributions (PSDs) and habits as measured during slow, Lagrangian-type spiral descents through deep subtropical and tropical cloud layers in Florida, Brazil, and Kwajalein, Marshall Islands, most of which were precipitating. The objective of the flight patterns was to learn more about how the PSDs evolved in the vertical and to obtain information of the vertical structure of microphysical properties. New instrumentation yielding better information on the concentrations of particles in the size (D) range between 0.2 and 2 cm, as well as improved particle imagery, produced more comprehensive observations for tropical stratiform precipitation regions and anvils than have been available previously. Collocated radar observations provided additional information on the vertical structure of the cloud layers sampled. Most of the spirals began at cloud top, with temperatures (T) as low as -50 C, and ended at cloud base or below the melting layer (ML). The PSDs broadened from cloud top towards cloud base, with the largest particles increasing in size from several millimeters at cloud top to one centimeter or larger towards cloud base. Some continued growth was noted in the upper part of the ML. Concentrations of particles less than 1 mm in size decreased with decreasing height. The result was a consistent change in the PSDs in the vertical. Similarly, systematic changes in the size dependence of the particle cross-sectional area was noted with decreasing height. Aggregation-as ascertained from both the changes in the PSDs and evolution of particle habits as observed in high detail with the cloud particle imager (CPI) probe-was responsible for these trends. The PSDs were generally well-represented by gamma distributions of the form N = N0 gamma D microns e- lambda gamma D that were fitted to the PSDs over 1-km horizontal intervals throughout the spirals. The intercept (N0 gamma), slope (lambda gamma), and dispersion (microns) values were derived for each PSD. Exponential curves (N = N0e- lambdaD; micron = 0) were also fitted to the distributions. The lambda gamma values for given spirals varied systematically with temperature as did the values of lambda (exponential), and the data generally conformed to values found in previous studies involving exponential fits to size distributions in mid-latitude frontal and cirrus layers. Considerable variability often noted in the PSD properties during the loops of individual spirals was manifested primarily in large changes in N0 gamma and N0, but micron, lambda gamma and lambda remained fairly stable. Temperature is not found to be the sole factor controlling lambda gamma or lambda but is a primary one. Direct relationships were found between lambda gamma and N0 gamma or lambda gamma and micron for the gamma distributions and lambda and N0 for the exponential. The latter relationship was not found as distinctly in earlier studies; observed PSDs in this study had better fidelity with less scatter. The micron values changed monotonically with T over the range of temperatures and were directly related to N0 gamma or lambda gamma, thereby reducing the number of variables in the PSD functional equation to two. In the upper part of the ML, N0 and lambda continued to decrease, and in the lower part these values began to increase as the largest particles melted. We developed general expressions relating various bulk microphysical, radar, and radiative transfer-related variables to N0 gamma and lambda gamma, useful for both tropical and mid-latitude clouds. These relationships facilitate the specification of a number of bulk properties in cloud and climate models. The results presented in this paper apply best to temperatures between 0 and -40 C, for which the measured radar reflectivities fall in the range of 0 to 25 dBZe.

  8. A regional climate study of Central America using the MM5 modeling system: results and comparison to observations

    NASA Astrophysics Data System (ADS)

    Hernandez, Jose L.; Srikishen, Jayanthi; Erickson, David J., III; Oglesby, Robert; Irwin, Daniel

    2006-12-01

    The Mesoscale Modeling system, version 3.6 (MM5) regional modeling system has been applied to Central America and has been evaluated against National Oceanic and Atmospheric Administration/National Climatic Data Center (NOAA/NCDC) daily observations and the Global Precipitation Climatology Project (GPCP) precipitation data. We compare model results and observations for 1997 and evaluate various climate parameters (temperature, wind speed, precipitation and water vapor mixing ratio), emphasizing the differences within the context of the station dependent geographical features and the land use (LU) categories. At 9 of the 16 analyzed stations the modeled temperature, wind speed and vapor mixing ratio are in agreement with observations with average model-observation differences consistently lower than 25%. MM5 has better performance at stations strongly impacted by monsoon systems, regions typified by low topography in coastal areas and areas characterized by evergreen, broad-leaf and shrub land vegetation types. At four stations the model precipitation is about a factor of 3-5 higher than the observations, while the simulated wind is roughly twice what is observed. These stations include two inland stations characterized by croplands close to water bodies; one coastal station in El Salvador adjacent to a mountain-based cropland area and one station at sea-level. This suggests that the model does not adequately represent the influence of topographic features and water bodies close to these stations. In general, the model agrees reasonably well with measurements and therefore provides an acceptable description of regional climate. The simulations in this study use only two seasonal maps of land cover. The main model discrepancies are likely attributable to the actual annual cycle of land-atmosphere vapor and energy exchange that has a temporal scale of days to weeks. These fluxes are impacted by surface moisture availability, albedo and thermal inertia parameters.

  9. [Cortisone-induced osteonecrosis: knowledge acquired from observations in man and comparison with the results of animal experimentation].

    PubMed

    Paolaggi, J B; Le Parc, J M; Durigon, M; Barres, D; Paolaggi, F; Arfi, S; Auquier, L

    1980-12-01

    Aseptic osteonecrosis is observed in 25% of cases after renal transplantation. This etiological variety of osteonecrosis is unusual in that it is frequently bilateral and has multiple localisations. Apart from the classical radiological signs, attention in attracted by isolated images of osteocondensation in the metaphyses and/or the diaphyses suggesting massive bony infarction and the appearances of fatigue fractures observed frequently (14%). In 43% of cases, the obvious necrosis was proceeded by early bone pain, around the 7 th day, during massive administration of corticosteroids in the prevention or cure of graft resection. This finding suggested to us that the best time to observe ischemia of the bone or marrow is very early and led us to undertake an experimental study in the rabbit. Two series of New Zealand White rabbits were treated with massive doses of corticosteroid and sacrificed between the 3rd and the 21st day. The treated animals presented an early peak of hyperlipemia from the 7th day onwards, and diffuse lesions of hepatic and renal steatosis. Fat emboli associated with appearances of parietal thrombosis were observed in most cases. In the same animals, there were also appearances of stage I or stage II necrosis. Referring to the description of bone marrow necrosis in stages by Arlet and Ficat, there was observed in all the series, a frequency of marrow lesions of all stages much higher in treated animals (16 out of 20) than in controls. Only one lesion of stage I was observed in controls; the difference was highly significant. (0,000001 < p < 0,00001). If one only considers necroses of stage II and III (10/20 in the treated group nil in controls) the frequency was still significant p < 0.001. The preliminary results of the fixation of tetracycline are reported. PMID:7006046

  10. The forensics of sub-surface processes on island volcanoes from integrated geodetic observations: results from Tenerife and Montserrat (Invited)

    NASA Astrophysics Data System (ADS)

    Gottsmann, J.

    2009-12-01

    Spatio-temporal variations in geodetic signals at active volcanoes provide important insight on governing subsurface processes. This contribution explores the phenomenology of volcanic unrest and eruptive activity from the perspective of both ground deformation and gravimetric investigations at an ocean island volcanic complex (Tenerife, Canary Islands) and an active andesitic arc volcano (Soufrière Hills volcano [SHV], Montserrat). Despite their marked differences in volcanic evolution and tectonic settings both volcanic systems show remarkable similarities in their subsurface processes. On Tenerife, during unrest in 2004-5, mass movement at depth was quantified by time-lapse gravimetric observations despite the absence of significant ground deformation. Shallow migration of hydrous fluids is identified as the main cause for the unrest marking the reactivation of the central volcanic complex after a century of quiescence. The combination of static and dynamic gravimetric data reveals a causality between the major structural building blocks of the island and the pattern of mass variations. Low density bodies underlie areas of maximum mass variations at the complex. Gravimetric data also indicate that the shallow plumbing system of the 3700 m tall Pico Teide/Pico Viejo composite volcano remained unaffected by the unrest. On Montserrat, time-lapse gravimetric data invoke the existence of a previously unrecognized fault zone beneath the centre of the island that is influenced by changes in stress distribution associated with volcanic activity at SHV. The fault zone either provides a trace for ground water flow or responds to a changed stress field via volcano-tectonic coupling with an elastic opening/closing of fractures. Continuous gravimetric (CG) data enabled the calibration of a new precision tidal model for the island resulting in a reduction of the signal-to-noise ratio by about one order of magnitude. Detided CG records reveal particular gravity perturbations a few minutes before the onset of Vulcanian eruptions in 2008. The gravity anomalies are inconsistent with mass variations in either a shallow magma reservoir or the active dyke-conduit system. Some waveforms may reflect very low-frequency seismicity (<0.05 Hz) associated with ensuing eruptions dominated by rock ballistics.

  11. Using self organising maps to explore ozone profile validation results - SCIAMACHY limb compared to ground-based lidar observations

    NASA Astrophysics Data System (ADS)

    van Gijsel, J. A. E.; Zurita-Milla, R.; Stammes, P.; Godin-Beekmann, S.; Leblanc, T.; Marchand, M.; McDermid, I. S.; Stebel, K.; Steinbrecht, W.; Swart, D. P. J.

    2014-04-01

    Traditional validation of atmospheric profiles is based on the intercomparison of two or more datasets in predefined ranges or classes of a given observational characteristic such as latitude or solar zenith angle. In this study we train a self organizing map (SOM) with a full time series of relative difference profiles of SCIAMACHY limb v5.02 and lidar ozone profiles from seven observation sites. Each individual observation characteristic is then mapped to the obtained SOM to investigate to which degree variation in this characteristic is explanatory for the variation seen in the SOM map. For the studied datasets, altitude-dependent relations for the global dataset were found between the difference profiles and studied variables. From the lowest altitude studied (18 km) ascending, the most influencing factors were found to be longitude, followed by solar zenith angle and latitude, sensor age and again solar zenith angle together with the day of the year at the highest altitudes studied here (up to 45 km). Clustering into three classes showed that there are also some local dependencies, with for instance one cluster having a much stronger correlation with the sensor age (days since launch) between 36 and 42 km. It was shown that the proposed approach provides a powerful tool for the exploring of differences between datasets without being limited to a-priori defined data subsets.

  12. Bi-Static Radar Observations Of The Ionosphere: Results from the NRAO/LL/MIT 150 to 1700 MHz System

    NASA Astrophysics Data System (ADS)

    Langston, G. I.

    2006-08-01

    Introduction: We report on the design and construction of a unique low- frequency, wide-bandwidth system for study of the Earths Ionosphere. The Massachusetts Institute of Technology's Lincoln Laboratory and NRAO are collaborating to study turbulent properties of the Earth's Ionosphere through the technique of Bi-Static Radar observations of spacecraft. Methods: Lincoln Laboratory generates schedules for spacecraft tracking that are automatically transferred and executed by NRAO in Green Bank. The radar tracking system at Millstone, MA transmits radar signals toward spacecraft. In Green Bank, the spacecraft are also tracked and reflected signals captured. Disk packs are sent daily to Lincoln Laboratory for analysis. Four frequency bands, each 70 MHz wide, are simultaneously sampled, allowing study of the Ionosphere over a large range of frequencies. Results: We have demonstrated full automatic operation of the facility. The control system is based on exchange of files that are placed on the internet, allowing easy monitoring of the proper operation of the system by all collaborators. Discussion: The construction phase of the system is complete and the first results of the bi-static radar observations are presented. We plan further upgrades to the system sensitivity and will initiate low frequency mapping and monitoring observations

  13. Stratospheric Assimilation of Chemical Tracer Observations Using a Kalman Filter. Pt. 2; Chi-Square Validated Results and Analysis of Variance and Correlation Dynamics

    NASA Technical Reports Server (NTRS)

    Menard, Richard; Chang, Lang-Ping

    1998-01-01

    A Kalman filter system designed for the assimilation of limb-sounding observations of stratospheric chemical tracers, which has four tunable covariance parameters, was developed in Part I (Menard et al. 1998) The assimilation results of CH4 observations from the Cryogenic Limb Array Etalon Sounder instrument (CLAES) and the Halogen Observation Experiment instrument (HALOE) on board of the Upper Atmosphere Research Satellite are described in this paper. A robust (chi)(sup 2) criterion, which provides a statistical validation of the forecast and observational error covariances, was used to estimate the tunable variance parameters of the system. In particular, an estimate of the model error variance was obtained. The effect of model error on the forecast error variance became critical after only three days of assimilation of CLAES observations, although it took 14 days of forecast to double the initial error variance. We further found that the model error due to numerical discretization as arising in the standard Kalman filter algorithm, is comparable in size to the physical model error due to wind and transport modeling errors together. Separate assimilations of CLAES and HALOE observations were compared to validate the state estimate away from the observed locations. A wave-breaking event that took place several thousands of kilometers away from the HALOE observation locations was well captured by the Kalman filter due to highly anisotropic forecast error correlations. The forecast error correlation in the assimilation of the CLAES observations was found to have a structure similar to that in pure forecast mode except for smaller length scales. Finally, we have conducted an analysis of the variance and correlation dynamics to determine their relative importance in chemical tracer assimilation problems. Results show that the optimality of a tracer assimilation system depends, for the most part, on having flow-dependent error correlation rather than on evolving the error variance.

  14. Using self-organising maps to explore ozone profile validation results - SCIAMACHY limb compared to ground-based lidar observations

    NASA Astrophysics Data System (ADS)

    van Gijsel, J. A. E.; Zurita-Milla, R.; Stammes, P.; Godin-Beekmann, S.; Leblanc, T.; Marchand, M.; McDermid, I. S.; Stebel, K.; Steinbrecht, W.; Swart, D. P. J.

    2015-05-01

    Traditional validation of atmospheric profiles is based on the intercomparison of two or more data sets in predefined ranges or classes of a given observational characteristic such as latitude or solar zenith angle. In this study we trained a self-organising map (SOM) with a full time series of relative difference profiles of SCIAMACHY limb v5.02 and lidar ozone profiles from seven observation sites. Each individual observation characteristic was then mapped to the obtained SOM to investigate to which degree variation in this characteristic is explanatory for the variation seen in the SOM map. For the studied data sets, altitude-dependent relations for the global data set were found between the difference profiles and studied variables. From the lowest altitude studied (18 km) ascending, the most influencing factors were found to be longitude, followed by solar zenith angle and latitude, sensor age and again solar zenith angle together with the day of the year at the highest altitudes studied here (up to 45 km). After accounting for both latitude and longitude, residual partial correlations with a reduced magnitude are seen for various factors. However, (partial) correlations cannot point out which (combination) of the factors drives the observed differences between the ground-based and satellite ozone profiles as most of the factors are inter-related. Clustering into three classes showed that there are also some local dependencies, with for instance one cluster having a much stronger correlation with the sensor age (days since launch) between 36 and 42 km. The proposed SOM-based approach provides a powerful tool for the exploration of differences between data sets without being limited to a priori defined data subsets.

  15. Seasonal Volatile Transport on Pluto: New Results from the 2013 Observing Season and Preparation for the New Horizons Encounter

    NASA Astrophysics Data System (ADS)

    Buratti, Bonnie; Dalba, Paul; Hicks, Michael; Chu, Devin; O'Neill, Ariel

    2014-05-01

    The New Horizons spacecraft will encounter Pluto in July 2015 for a fast flyby and close investigation of the dwarf planet and its five known moons. With a time-constrained mission it is essential to acquire ground-based observations for context and for a longer temporal excursion. An observing program at JPL's Table Mountain Observatory (TMO) has been in operation during the past decade and a half, with a goal of seeking temporal changes on Pluto's surface. This program, which has been largely implemented by undergraduate students, seeks changes in the color and albedo of Pluto. Seasonal transport of volatiles is predicted to occur on Pluto, and this transport should be detectable through changes in its rotational light curve as well as in color and albedo, once all variations due to viewing geometry have been accounted for. Occultation studies have shown that there has been a steady increase in Pluto's atmospheric pressure over the past two decades, so concomitant sublimation and recondensation of frost has likely occurred, as predicted by volatile transport models. Rotational light curves of Pluto through time have been created for static frost models based on images from the Hubble Space Telescope. These models, which account for changes in viewing geometry, have been compared with observed light curves obtained between 1950 and 2013. No evidence for transport was evident prior to 2000. However, starting in the early part of the millennium, evidence from new observations by HST (Buie et al., 2010, Astron. J. 139, 1128) and rotational light curves obtained in 2007-2008 (Hicks et al. 2008, B.A.A.S. 40, 460) suggest changes in the frost pattern on Pluto's surface. An extensive and dedicated observing program at TMO was conducted over a period of five months in 2013 during Pluto's opposition. New observations of Pluto's light curve from the 2013 show continued volatile transport, but the most striking change is in Pluto's color. As the New Horizons encounter approaches, Pluto's surface appears to be reddening, which would be consistent with the removal of nitrogen frost from its surface and the uncovering of photolyzed, methane-rich substrate underneath. New Horizons will most likely encounter an active Pluto. Funded by NASA.

  16. A stratospheric intrusion at the subtropical jet over the Mediterranean Sea: air-borne remote sensing observations and model results

    NASA Astrophysics Data System (ADS)

    Weigel, K.; Hoffmann, L.; Gnther, G.; Khosrawi, F.; Olschewski, F.; Preusse, P.; Spang, R.; Stroh, F.; Riese, M.

    2012-09-01

    Remote sensing measurements from the Cryogenic Infrared Spectrometers and Telescope for the Atmosphere - New Frontiers (CRISTA-NF) during a flight on 29 July 2006 are presented. This flight is part of the AMMA-SCOUT-O3 measurement campaign, where CRISTA-NF was deployed on the high-flying research aircraft M55-Geophysica. The flight path was located over Italy and the Mediterranean Sea and crossed over the subtropical jet twice. Measurements of temperature, and the volume mixing ratios of water vapor (H2O), ozone (O3), nitric acid (HNO3) and peroxyacetyl nitrate (PAN) are available with a vertical resolution of up to 500 m between about 6 to 21 km altitude. CRISTA-NF observes these trace gases simultaneously and provides a quasi-2-D view of the transition region between the troposphere and the stratosphere. The observation of these different trace gases allows to determine tropospheric and stratospheric air masses. As expected, higher abundances are found where the main source of the trace gases is located: in the stratosphere for O3 and in the troposphere for H2O and PAN. Tracer-tracer correlations between O3 and PAN are used to identify the mixed tropospheric and lowermost stratospheric air at the subtropical jet and around the thermal tropopause north of the jet. An intrusion of stratospheric air into the troposphere associated with the subtropical jet is found in the CRISTA-NF observations. The observations indicate that the intrusion is connected to a tropopause fold which is not resolved in the ECMWF analysis data. The intrusion was reproduced in a simulation with the Chemical Lagrangian Model of the Stratosphere (CLaMS). The CLaMS simulation shows, that the lowermost stratospheric air masses in the intrusion where transported along the the subtropical jet. The tropospheric air masses around the intrusion originate from the vicinity of the Asian monsoon anticyclone. This work discusses the nature of the observed processes at the subtropical jet based on the CRISTA-NF observations and the CLaMS simulation.

  17. Description and primary results of Total Solar Irradiance Monitor, a solar-pointing instrument on an Earth observing satellite

    NASA Astrophysics Data System (ADS)

    Wang, Hongrui; Fang, Wei; Li, Huiduan

    2015-04-01

    Solar driving mechanism for Earth climate has been a controversial problem for centuries. Long-time data of solar activity is required by the investigations of the solar driving mechanism, such as Total Solar Irradiance (TSI) record. Three Total Solar Irradiance Monitors (TSIM) have been developed by Changchun Institute of Optics, Fine Mechanics and Physics for China Meteorological Administration to maintain continuities of TSI data series which lasted for nearly 4 decades.The newest TSIM has recorded TSI daily with accurate solar pointing on the FY-3C meteorological satellite since Oct 2013. TSIM/FY-3C has a pointing system for automatic solar tracking, onboard the satellite designed mainly for Earth observing. Most payloads of FY-3C are developed for observation of land, ocean and atmosphere. Consequently, the FY-3C satellite is a nadir-pointing spacecraft with its z axis to be pointed at the center of the Earth. Previous TSIMs onboard the FY-3A and FY-3B satellites had no pointing system, solar observations were only performed when the sun swept through field-of-view of the instruments. And TSI measurements are influenced inevitably by the solar pointing errors. Corrections of the solar pointing errors were complex. The problem is now removed by TSIM/FY-3C.TSIM/FY-3C follows the sun accurately by itself using its pointing system based on scheme of visual servo control. The pointing system is consisted of a radiometer package, two motors for solar tracking, a sun sensor and etc. TSIM/FY-3C has made daily observations of TSI for more than one year, with nearly zero solar pointing errors. Short time-scale variations in TSI detected by TSIM/FY-3C are nearly the same with VIRGO/SOHO and TIM/SORCE.Instrument details, primary results of solar pointing control, solar observations and etc will be given in the presentation.

  18. Air Quality Observations from Space: Results from the Ozone Monitoring Instrument (OMI) and Expected Results from the TROPOspheric Monitoring Instrument (TROPOMI)

    NASA Astrophysics Data System (ADS)

    Veefkind, J. P.; Boersma, K. F.; van der A, R.; Eskes, H.; Kleipool, Q.; Krotkov, N.; Aben, I.; de Vries, J.; Ingmann, P.; Tamminen, J.; Joiner, J.; Bhartia, P. K.; Levelt, P. F.

    2012-04-01

    Air quality is one of the largest societal challenges, especially in large urbanized and industrialized regions of the world. Reduced air quality has adverse health effects, and also results in reduced crop yields. In addition, there are strong links between air quality and climate change. Air quality has traditionally been monitored by ground-based networks. In the previous decade the observation capabilities have been extended with measurements from space, most notable from the Ozone Monitoring Instrument (OMI), the SCanning Imaging Absorption spectroMeter for Atmospheric CartograpHY (SCIAMACHY) and the Global Ozone Monitoring Experiment (GOME-1/2). Whereas the satellite instruments do not provide concentrations at the surface level, they provide unique global information on the spatial distribution and transport of pollutants. Over the last decade the quality of the satellite data for tropospheric species like nitrogen dioxide, carbon monoxide, sulfur dioxide, formaldehyde and aerosols have matured rapidly. Several data products now contribute to the monitoring and forecasting of air quality through data assimilation techniques, as for example developed in the MACC (http://www.gmes-atmosphere.eu/) project. Apart from directly contributing through data assimilation, satellite data are also used for the top-down quantification of emission sources and understanding of atmospheric processes, thus improving chemistry transport models. The OMI instrument, which was launched in July 2004, was the first instrument that combined daily global coverage with high spatial resolution of 13x24 km2 at nadir. The OMI data have attracted many new users and have resulted in several new applications. The TROPOMI instrument on the ESA/GMES Sentinel 5 precursor satellite, planned for launch in 2015, will be the first in a series of European satellite sensors dedicated for monitoring atmospheric composition changes in the timeframe 2015-2030. The TROPOMI instrument has a heritage to both OMI and SCIAMACHY. With a spatial resolution as high as 7x7 km2, higher signal-to-noise and extended spectral coverage, TROPOMI will provide exciting new information on the changing composition of the troposphere. The planned formation flying with the US afternoon NPP/JPSS satellites will enable important synergies, including the usage of high spatial resolution imager (VIIRS) data for enhanced cloud clearing of the TROPOMI data. The availability of the morning EUMETSAT MetOp (GOME-2 and IASI) operational observations will provide complementary information on the diurnal variability. In this contribution an overview will be given of successes of OMI for air quality monitoring and research. In addition, the European satellite missions for atmospheric composition within the ESA/GMES Sentinel programme will be presented, with a focus on the TROPOMI instrument design and performance status.

  19. Public medical shows.

    PubMed

    Walusinski, Olivier

    2014-01-01

    In the second half of the 19th century, Jean-Martin Charcot (1825-1893) became famous for the quality of his teaching and his innovative neurological discoveries, bringing many French and foreign students to Paris. A hunger for recognition, together with progressive and anticlerical ideals, led Charcot to invite writers, journalists, and politicians to his lessons, during which he presented the results of his work on hysteria. These events became public performances, for which physicians and patients were transformed into actors. Major newspapers ran accounts of these consultations, more like theatrical shows in some respects. The resultant enthusiasm prompted other physicians in Paris and throughout France to try and imitate them. We will compare the form and substance of Charcot's lessons with those given by Jules-Bernard Luys (1828-1897), Victor Dumontpallier (1826-1899), Ambroise-Auguste Libault (1823-1904), Hippolyte Bernheim (1840-1919), Joseph Grasset (1849-1918), and Albert Pitres (1848-1928). We will also note their impact on contemporary cinema and theatre. PMID:25273491

  20. Testing of Lunar Permanently Shadowed Regions for Water Ice: LEND Results for about Three Years of Observations

    NASA Astrophysics Data System (ADS)

    Sanin, A.; Mitrofanov, I.; Litvak, M.; Boynton, W. V.; Chin, G.; Evans, L. G.; Garvin, J.; Golovin, D.; Harshman, K.; McClanahan, T. R.; Malakhov, A.; Milikh, G. M.; Sagdeev, R.; Starr, R. D.

    2012-12-01

    Introduction: More than 50 years ago, it was sug-gested that some areas near the lunar poles are suffi-ciently cold to trap and preserve for a very long time (~Gy) hydrogen bearing volatiles, either primordial or produced at the Moon via solar wind interactions or brought to the Moon as water ice by comets and mete-oroids [1,2]. The results of observations made by radar onboard the Clementine spacecraft and by neutron (LPNS) and gamma-ray (LPGRS) spectrometers onboard the Lunar Prospector mission have been inter-preted as an enhancement of hydrogen abundance in permanently shadowed regions (PSRs) [3]. Unfortu-nately, the spatial resolution of these instruments were much broader than the size of any largest PSRs [4] requiring model dependent data deconvolution to res-lve signal from PSRs itself. Data Analysis: We would like to present updated results of analysis of Lunar Exploration Neutron Detector (LEND) data for about three years of lunar mapping. Data measured by collimated LEND detectors allows one to look at neutron flux distribution at Moon poles with much better spatial resolution then was achieved at previous space missions. Using the LEND data we had tested the hypothesis that all PSRs are contain a large amount of water ice permafrost and test for hydrogen presents in regolith of regions outside of PSRs. Discussion: Both analyses of individual PSRs and studies of groups of PSRs have shown that these spots of extreme cold at lunar poles are not associated with a strong effect of epithermal neutron flux suppression [5]. We found only three large PSRs, Shoemaker and Cabeus in the South and Rozhdestvensky U in the North, which manifest significant neutron suppression, from -5.5% to -14.9%. All other PSRs have much smaller suppression, no more than few percentages, if at all. Some PSRs even display excess of neutron emis-sion in respect to sunlit vicinity around them. Testing PSRs collectively, we have not found any average suppression for them. Only group of 18 large PSRs, with area >200 km2, show a marginal effect of small average suppression, ~2%, with low statistical confidence. A ~2% suppression corresponds to ~125 ppm of hydrogen taking into account the global neutron suppression near the lunar poles and assuming a homogeneous Hydrogen distribution in depth in the regolith [6]. References: [1] Arnold, J. R. (1979) JGR, 84, 5659-5668. [2] Watson, K., Murray B. C. and Brown H. (1961) JGR, 66, 3033-3045. [3] Feldman W. C. et al. (2001) JGR, 106, 23231-23252. [4] Maurice S. et al. (2004) JGR, 109, E07S04, 40 PP. [5] Mitrofanov I. G. et al. (2010) Science, 330, 483. [6] Sanin A.B. et al. (2012) JGR, 117, E00H26

  1. Arctic Sea Ice Thickness Distribution as an Indicator of Arctic Climate Change - Synthesis of Model Results and Observations

    NASA Astrophysics Data System (ADS)

    Maslowski, Wieslaw; Clement Kinney, Jaclyn; Jakacki, Jaromir; Osinski, Robert; Zwally, Jay

    2010-05-01

    The Arctic region is an integral part of the Earth's climate system through its influence on global surface energy and moisture fluxes and on atmospheric and oceanic circulation. Within the Arctic, its sea ice cover is possibly the most sensitive indicator of the polar amplified global warming and of the state of Arctic climate system as a whole. Hence changes in Arctic climate and the decline of multi-year sea ice cover have significant ramifications to the entire pan-Arctic region and beyond. Having the recorded average global surface temperature about 0.54C (0.96F) above the 20th Century average the decade of 2000-2009 has been the warmest of the 130-year record, with the maximum positive temperatures anomalies in the northern high latitude regions. Satellite records of the Arctic sea ice show a decreasing and accelerating trend in ice extent and concentration since the late 1979, as a result of the global warming. More importantly there is growing evidence that the Arctic sea ice thickness and volume have been decreasing at even faster rate. This means that our knowledge of the Arctic sea ice melt might be significantly biased due to the interpretation of 2-dimensional sea ice extent / concentration records only instead of ice thickness and volume. The rates of recent ice thickness and volume melt derived from our pan-Arctic coupled ice-ocean model results combined with recent remotely sensed data suggest an accelerating negative trend. This trend is robust and lends credence to the postulation that the Arctic not only might but it is likely to be ice-free during the summer in the near future. However, global climate models vary widely in their predictions of warming and the rate of Arctic ice melt, suggesting it may take anywhere from a couple of decades to more than a century to melt most of the summer sea ice cover. Also many regional models are limited in their representation of the rapid Arctic sea ice thinning and volume loss. The inability of models to reproduce the recent warming and ice melt in the Arctic Ocean diminishes their accuracy of future climate predictions, which bears significant consequences for both science of climate change and policymaking. Some of the critical model limitations include: sea ice thickness distribution, deformation, variability and export, air-ice-sea interactions, northward oceanic/atmospheric heat convergence, and freshwater export into the North Atlantic. We argue that high resolution combined with advanced model physics is required to realistically model such processes and to improve predictive skills in general circulation models. Further studies involving observations and better models are needed to verify how rapidly and why Arctic sea ice is melting and to re-evaluate predictions of a summer ice-free Arctic Ocean.

  2. Children's school-breakfast reports and school-lunch reports (in 24-h dietary recalls): conventional and reporting-error-sensitive measures show inconsistent accuracy results for retention interval and breakfast location.

    PubMed

    Baxter, Suzanne D; Guinn, Caroline H; Smith, Albert F; Hitchcock, David B; Royer, Julie A; Puryear, Megan P; Collins, Kathleen L; Smith, Alyssa L

    2016-04-01

    Validation-study data were analysed to investigate retention interval (RI) and prompt effects on the accuracy of fourth-grade children's reports of school-breakfast and school-lunch (in 24-h recalls), and the accuracy of school-breakfast reports by breakfast location (classroom; cafeteria). Randomly selected fourth-grade children at ten schools in four districts were observed eating school-provided breakfast and lunch, and were interviewed under one of eight conditions created by crossing two RIs ('short' - prior-24-hour recall obtained in the afternoon and 'long' - previous-day recall obtained in the morning) with four prompts ('forward' - distant to recent, 'meal name' - breakfast, etc., 'open' - no instructions, and 'reverse' - recent to distant). Each condition had sixty children (half were girls). Of 480 children, 355 and 409 reported meals satisfying criteria for reports of school-breakfast and school-lunch, respectively. For breakfast and lunch separately, a conventional measure - report rate - and reporting-error-sensitive measures - correspondence rate and inflation ratio - were calculated for energy per meal-reporting child. Correspondence rate and inflation ratio - but not report rate - showed better accuracy for school-breakfast and school-lunch reports with the short RI than with the long RI; this pattern was not found for some prompts for each sex. Correspondence rate and inflation ratio showed better school-breakfast report accuracy for the classroom than for cafeteria location for each prompt, but report rate showed the opposite. For each RI, correspondence rate and inflation ratio showed better accuracy for lunch than for breakfast, but report rate showed the opposite. When choosing RI and prompts for recalls, researchers and practitioners should select a short RI to maximise accuracy. Recommendations for prompt selections are less clear. As report rates distort validation-study accuracy conclusions, reporting-error-sensitive measures are recommended. PMID:26865356

  3. Absolute magnitudes and slope parameters for 250,000 asteroids observed by Pan-STARRS PS1 - Preliminary results

    NASA Astrophysics Data System (ADS)

    Vere, Peter; Jedicke, Robert; Fitzsimmons, Alan; Denneau, Larry; Granvik, Mikael; Bolin, Bryce; Chastel, Serge; Wainscoat, Richard J.; Burgett, William S.; Chambers, Kenneth C.; Flewelling, Heather; Kaiser, Nick; Magnier, Eugen A.; Morgan, Jeff S.; Price, Paul A.; Tonry, John L.; Waters, Christopher

    2015-11-01

    We present the results of a Monte Carlo technique to calculate the absolute magnitudes (H) and slope parameters (G) of ?240,000 asteroids observed by the Pan-STARRS1 telescope during the first 15 months of its 3-year all-sky survey mission. The system's exquisite photometry with photometric errors ? 0.04mag , and well-defined filter and photometric system, allowed us to derive accurate H and G even with a limited number of observations and restricted range in phase angles. Our Monte Carlo method simulates each asteroid's rotation period, amplitude and color to derive the most-likely H and G, but its major advantage is in estimating realistic statistical + systematic uncertainties and errors on each parameter. The method was tested by comparison with the well-established and accurate results for about 500 asteroids provided by Pravec et al. (Pravec, P. et al. [2012]. Icarus 221, 365-387) and then applied to determining H and G for the Pan-STARRS1 asteroids using both the Muinonen et al. (Muinonen, K. et al. [2010]. Icarus 209, 542-555) and Bowell et al. (Bowell, E. et al. [1989]. Asteroids III, Chapter Application of Photometric Models to Asteroids. University of Arizona Press, pp. 524-555) phase functions. Our results confirm the bias in MPC photometry discovered by Juri? et al. (Juri?, M. et al. [2002]. Astrophys. J. 124, 1776-1787).

  4. Project VeSElkA : Preliminary results for CP stars recently observed with ESPaDOnS

    NASA Astrophysics Data System (ADS)

    Khalack, Viktor; LeBlanc, Francis

    2015-01-01

    We present the first results for the estimation of gravity and effective temperature of poorly studied chemically peculiar stars recently observed with the spectropolarimeter ESPaDOnS at CFHT in the frame of the VeSElkA (Vertical Stratification of Elements Abundance) project. A grid of theoretical stellar atmosphere models with the corresponding fluxes has been calculated using the PHOENIX code. We have used these fluxes to fit Balmer line profiles employing the code FITSB2 that produces estimates of the effective temperature, surface gravity and radial velocity for each star.

  5. Energetic ion and electron observations of the geomagnetic plasma sheet boundary layer - Three-dimensional results from ISEE 1

    NASA Technical Reports Server (NTRS)

    Spjeldvik, W. N.; Fritz, T. A.

    1981-01-01

    A description of energetic ion and electron behavior in the geomagnetic plasma sheet boundary layer is presented based on observations made by the medium-energy particle experiment on board ISEE 1. Three-dimensional observations of ions of energies 24-2081 keV and electrons of energies 22.5-1200 keV were obtained by the NOAA/WAPS instrument near the center of the magnetotail at a distance of approximately 15 earth radii. Large-scale motions of plasma sheet energetic particles are observed as an apparent result of a series of magnetospheric disturbances (substorms), which are characterized by substantial contractions and expansions. Ion flow velocity in a distinct boundary layer in energetic ions has been found to be in the earthward direction in each of the five ISEE 1 boundary crossings. Boundary layer motion during one of these crossings is interpreted as large-amplitude boundary waves with periodicities of a few minutes superimposed on the general plasma sheet behavior associated with the substorm process.

  6. High Spectral Resolution Observation of Decimetric Radio Spikes Emitted by Solar Flares - First Results of the Phoenix-3 Spectrometer

    NASA Astrophysics Data System (ADS)

    Benz, Arnold O.; Monstein, Christian; Beverland, Michael; Meyer, Hansueli; Stuber, Bruno

    2009-12-01

    A new multichannel spectrometer, Phoenix-3, is in operation having capabilities to observe solar flare radio emissions in the 0.1 - 5 GHz range at an unprecedented spectral resolution of 61.0 kHz with high sensitivity. The present setup for routine observations allows measuring circular polarization, but requires a data compression to 4096 frequency channels in the 1 - 5 GHz range and to a temporal resolution of 200 ms. First results are presented by means of a well observed event that included narrowband spikes at 350 - 850 MHz. Spike bandwidths are found to have a power - law distribution, dropping off below a value of 2 MHz for full width at half maximum (FWHM). The narrowest spikes have a FWHM bandwidth less than 0.3 MHz or 0.04% of the central frequency. The smallest half-power increase occurs within 0.104 MHz at 443.5 MHz, which is close to the predicted natural width of maser emission. The spectrum of spikes is found to be asymmetric, having an enhanced low-frequency tail. The distribution of the total spike flux is approximately an exponential.

  7. Television Quiz Show Simulation

    ERIC Educational Resources Information Center

    Hill, Jonnie Lynn

    2007-01-01

    This article explores the simulation of four television quiz shows for students in China studying English as a foreign language (EFL). It discusses the adaptation and implementation of television quiz shows and how the students reacted to them.

  8. Non-adherence to antihypertensive medication is very common among resistant hypertensives: results of a directly observed therapy clinic.

    PubMed

    Hameed, M A; Tebbit, L; Jacques, N; Thomas, M; Dasgupta, I

    2016-02-01

    Resistant hypertension is common among the hypertensive population with reported prevalence of 12 to 15%. These patients have a higher cardiovascular risk and consequently a poorer cardiovascular prognosis. Suboptimal adherence with antihypertensive medication is a common contributing factor in apparent treatment-resistant hypertension. Patients were observed taking their medications under direct supervision at our directly observed therapy (DOT) clinic. At the DOT clinic visit, patients were fitted with a 24-h ambulatory blood pressure (ABP) monitor and each drug, at currently prescribed dose, was administered by a nurse; at an hourly interval and patient observed for 7?h. ABP readings between pre and post DOT clinic were compared. Fifty out of 56 patients had complete data on the ABP. Twenty four were female and the mean (s.d.) age was 62.0 (11.0) years. On the basis of the study methods that differentiated patients according to their BP response during the DOT clinic, twenty-five (50.0%) patients were deemed to be truly resistant (24-h ambulatory systolic blood pressure (SBP) fall <5?mm?Hg) and the remaining 25 were deemed to have clinically significant non-adherence (24-h ambulatory SBP fall ?5?mm?Hg) to prescribed therapy. In non-adherent patients, the mean 24-h ambulatory BP drop observed was 19.5/9.4?mm?Hg (P<0.001 for both). Our results suggest that non-adherence is very common among patients considered to have apparent treatment-resistant hypertension. DOT clinic can be an effective method of identifying the truly resistant hypertensive patients. PMID:25947275

  9. Effects and safety of I-metaiodobenzylguanidine (MIBG) radiotherapy in malignant neuroendocrine tumors: results from a multicenter observational registry.

    PubMed

    Yoshinaga, Keiichiro; Oriuchi, Noboru; Wakabayashi, Hiroshi; Tomiyama, Yuuki; Jinguji, Megumi; Higuchi, Tetsuya; Kayano, Daiki; Fukuoka, Makoto; Inaki, Anri; Toratani, Ayane; Okamoto, Shozo; Shiga, Tohru; Ito, Yoichi M; Nakajo, Masatoyo; Nakajo, Masayuki; Kinuya, Seigo

    2014-01-01

    Effective treatments for malignant neuroendocrine tumors are under development. While iodine-131 metaiodobenzylguanidine (I-MIBG) radiotherapy has been used in the treatment of malignant neuroendocrine tumors, there are few studies evaluating its therapeutic effects and safety in a multicenter cohort. In the current study, we sought to evaluate the effects and safety of I-MIBG therapy for conditions including malignant pheochromocytoma and paraganglioma within a multicenter cohort. Forty-eight malignant neuroendocrine tumors (37 pheochromocytoma and 11 paraganglioma) from four centers underwent clinical I-MIBG radiotherapy. The tumor responses were observed before and 3 to 6 months after the I-MIBG radiotherapy in accordance with RECIST criteria. We also evaluated the data for any adverse effects. The four centers performed a total of 87 I-MIBG treatments on 48 patients between January 2000 and March 2009. Of the treatments, 65 were evaluable using RECIST criteria. One partial response (PR), 40 stable disease (SD), and 9 progressive disease (PD) in malignant pheochromocytoma were observed after each treatment. Fourteen SD and one PD-were observed in paraganglioma. Patients with normal hypertension (systolic blood pressure (BP) > 130 mmHg) showed significantly reduced systolic BP after the initial follow-up (n=10, 138.18.2 to 129.513.5 mmHg, P=0.03). In adult neuroendocrine tumors with a treatment-basis analysis, there were side effects following 41 treatments (47.1%) and most of them (90.2%) were minor. In this multicenter registry, PR or SD was achieved in 84.6% of the treatment occasions in adult neuroendocrine tumors through I-MIBG radiotherapy. This indicated that most of the I-MIBG radiotherapy was performed safely without significant side effects. PMID:25214026

  10. VERTICAL MIXING AND CHEMISTRY OVER AN ARID URBAN SITE: FIRST RESULTS FROM AIRCRAFT OBSERVATIONS MADE DURING THE PHOENIX SUNRISE CAMPAIGN.

    SciTech Connect

    BERKOWITZ,C.M.; SPRINGSTON,S.R.; DORAN,J.C.; FAST,J.D.

    2002-01-13

    The role of boundary layer mixing is increasingly recognized as an important factor in determining the concentrations of ozone and other trace gases near the surface. While the concentrations at the surface can vary widely due to horizontal transport of chemical plumes, the boundary layer is also characterized by turbulence that follows a diurnal cycle in height and intensity. Surface oxidant concentrations can therefore undergo significant changes even in the absence of photochemistry. A central goal of the Phoenix 2001 Field Campaign was to study vertical mixing with the onset of convection and to quantify the effect of this mixing on chemistry within an urban boundary layer. As part of this study, a series of low altitude aircraft sampling flights were made over the Greater Phoenix area between June 16-30, 2001. The resulting observations, in conjunction with a series of surface measurements and meteorological observations, are being used to study the vertical transport and reactivity of ozone and ozone-precursors shortly after sunrise. Additional details of this campaign are given in Doran, et al. (2002). It was anticipated that turbulence over Phoenix at night would be suppressed as a result of cooling of the boundary layer over the city. By sampling shortly after sunrise, we hoped to collect measurements above the residual nocturnal stable layer and to continue sampling through the developmental period of a convectively active boundary layer. We report here on the first analysis of these observations, made from a Gulstream-1 (G-1) aircraft operated by the U.S. Department of Energy.

  11. Short-Term Chromospheric Variability in alpha Tauri (K5 III): Results from IUE Time Series Observations

    NASA Technical Reports Server (NTRS)

    Cuntz, Manfred; Deeney, Bryan D.; Brown, Alexander; Stencel, Robert E.

    1996-01-01

    We evaluate time series observations of chromospheric lines (Mg II, Mg I, and C II) for the K giant alpha Tau obtained using the IUE LWP camera at high dispersion. These observations cover a time span of about 2 weeks in 1994 February-March and were designed to resolve variations occurring within hours, days, and weeks. We consider the observational results in relation to theoretical acoustic heating models, motivated by the fact that alpha Tau may exhibit a basal (i.e., minimum) level of chromospheric activity. The data reveal flux variations between the extremes of 8% in Mg II h+k and 15% in each emission component. These variations occur on timescales as short as 8 hr but not on timescales longer than approx.3 days. For the h and k components, flux variations occurring on a timescale as short as 1.5 hr are also found. These changes are often not correlated (and are sometimes even anticorrelated), leading to remarkable differences in the h/k ratios. We argue that these results are consistent with the presence of strong acoustic shocks, which can lead to variable Mg II line emission when only a small number of strong shocks are propagating through the atmosphere. We deduce the electron density in the C II lambda 2325 line formation region to be log(base e) of N. approx. equals 9.0, in agreement with previous studies. Our data provide evidence that the Mg II basal flux limit for K giants might be a factor of 4 higher than suggested by Rutten et al.

  12. Trans-polar Transmission of Pc 3-4 ULF Waves: Results from Cluster and Antarctic Observations

    NASA Astrophysics Data System (ADS)

    Pilipenko, V.; Chugunova, O.; Engebretson, M.; Glassmeier, K.; Vellante, M.; Delauretis, M.; Ponomarenko, P.

    2005-12-01

    The possibility of transpolar transmission of Pc3-4 ULF waves is considered using data from search-coil magnetometers from AGOs D5 and D6 in Antarctica, situated on opposite sides of the geomagnetic pole. The diurnal variation of the number of time intervals when Pc3-4 ULF wave activations are simultaneously observed at both stations shows that synchronous ULF activity increases when one of the stations, especially P6, passes local noon. The Cluster satellites have been used, in conjunction with ground observations, to analyze a Pc3-4 wave event in the polar cap. The wave magnetic power was predominantly in the field-aligned component and all components correlated well with small phase delay between all four satellites. Ground-satellite correlations in this frequency range demonstrate that traveling compressional Pc3-4 waves on open field lines are related to the ground wave activity in the polar cap. Additionally, an analysis of a campaign of ULF geomagnetic field measurements during November 2003 at the new Italian/French base Dome C, close to the geomagnetic pole, is presented together with a comparison with simultaneous measurements conducted with similar search-coil magnetometers at McMurdo, Terra Nova Bay, Casey, and South Pole. The variable solar wind conditions allowed to monitor the Pc 3-4 ULF pulsation activity both during quiet period and strong magnetic storm. For quiet magnetospheric conditions, the pulsation power maximizes around local magnetic noon at poleward auroral boundary, but it does not show any evidence for a diurnal modulation in the polar cap. During a strong geomagnetic storm, the wave activity at all stations seem to be driven preferably by strong solar wind pressure pulses. Several Pc3-4 wave events were simultaneously detected in the polar cap and onboard Cluster satellites. These observations indicate the possibility of additional channel of Pc3-4 wave transmission from the upstream region to the ground - via the open field lines at polar latitudes, where mode conversion occurs owing to an unidentified mechanism.

  13. A Census of X-Ray Gas in NGC 1068: Results from 450ks of Chandra HETG Observations

    NASA Technical Reports Server (NTRS)

    Kallman, T.; Evans, Daniel A.; Marshall, H.; Canizares, C.; Longinotti, A.; Nowak, M.; Schulz, N.

    2013-01-01

    We present models for the X-ray spectrum of the Seyfert 2 galaxy NGC 1068. These are fitted to data obtained using the High Energy Transmission Grating (HETG) on the Chandra X-ray observatory. The data show line and radiative recombination continuum (RRC) emission from a broad range of ions and elements. The models explore the importance of excitation processes for these lines including photoionization followed by recombination, radiative excitation by absorption of continuum radiation and inner shell fluorescence. The models show that the relative importance of these processes depends on the conditions in the emitting gas, and that no single emitting component can fit the entire spectrum. In particular, the relative importance of radiative excitation and photoionization/recombination differs according to the element and ion stage emitting the line. This in turn implies a diversity of values for the ionization parameter of the various components of gas responsible for the emission, ranging from log(Epsilon)=1 - 3. Using this, we obtain an estimate for the total amount of gas responsible for the observed emission. The mass flux through the region included in the HETG extraction region is approximately 0.3 Solar Mass/yr assuming ordered flow at the speed characterizing the line widths. This can be compared with what is known about this object from other techniques.

  14. The New York Harbor Observation System (NYHOS): Preliminary Results on Real-Time Quality Control of Hourly Reported Data

    NASA Astrophysics Data System (ADS)

    Dardier, G. M.; Bruno, M. S.; Blumberg, A. F.; Fullerton, B. J.; Herrington, T. O.; Zagrai, E.; Turner, J. W.

    2004-05-01

    The New York Harbor Observation System is a regional integrated system dedicated to monitoring the New York Harbor area through model-directed observations and model forecast for security and surveillance purposes. Observations encompass a unique combination of sensors, both at fixed stations and upon dynamic platforms. Measurements include surface and bottom CTD (YSI) from numerous shore-side and buoy stations, moored ADCP (RDI) and bottom CTD (SeaBird) from a cross river transect, High Frequency radars (CODAR) as well as surface CTD (Seabird) from a series of ferries. The combined data allow an optimal fine coverage of the studied area of the order of 50{km}2, within a time window of 60 min. Transmission is performed hourly via wireless transmission (both UHF conventional radio and cellular), cable or regular telephone lines. In order to insure the quality of the newly collected data, we proceed in two steps. First, we test our data for quality control using the NDBC man-machine mix data control protocols. These protocols concern in particular data associated with physical processes, such as sea level, water temperature, conductivity and salinity. They focus on transmission errors, gross range and time-continuity checks and wind gust to wind speed checks, following D.B. Gilhousen (1998) specifications. We then test our data for quality control using protocols based on static as well as dynamic checks as proposed by Miller et al. (2003). We address in particular spatial and temporal data disparity resulting from the operational mode of the instrumented ferries using wavelets following Mallat, (1998). Assuming the physical data is temporally constant within a one hour time frame, the fine model grid, used by the system's nowcast and forecast model, is filled using simple data interpolation. The modified data persistence analysis can then be used as background for horizontal consistency checks. Results of the two approaches are compared in terms of detection percentage and false alarm percentage. Shore-based and moored CTD are used as reference values to test the ferry data when possible. Then, results on salinity and temperature disparities in the New York harbor as functions of space and time scales are shown. Adapted algorithms, derived from these results, are discussed in details.

  15. Air Quality Observations from Space: Results from the Ozone Monitoring Instrument (OMI) and Expected Results from the TROPOspheric Monitoring Instrument (TROPOMI)

    NASA Astrophysics Data System (ADS)

    Veefkind, J. P.; Boersma, F. F.; van der A, R. J.; Eskes, H. J.; de Haan, J. F.; Kleipool, Q.; Krotkov, N. A.; Aben, I.; de Vries, J.; Ingmann, P.; Tamminen, J.; Joiner, J.; Bhartia, P. K.; Levelt, P.

    2011-12-01

    Air quality is one of the largest societal challenges, especially in large urbanized and industrialized regions of the world. Reduced air quality has adverse health effects, and also results in reduced crop yields. In addition, there are strong links between air quality and climate change. Traditionally, air quality has been monitored by ground-based networks. In the previous decade the observation capabilities have been extended with measurements from space, most notable from the Ozone Monitoring Instrument (OMI), the SCanning Imaging Absorption spectroMeter for Atmospheric CartograpHY (SCIAMACHY) and the Global Ozone Monitoring Experiment (GOME-1/2). Whereas the satellite instruments do not provide concentrations at the surface level, they provide unique global information on the spatial distribution and transport of pollutants. Over the last decade the quality of the satellite data for tropospheric species like nitrogen dioxide, carbon monoxide, sulfur dioxide, formaldehyde and aerosols have matured rapidly. Several data products now contribute to the monitoring and forecasting of air quality through data assimilation techniques, most notably as developed in the EU GEMS and MACC (http://www.gmes-atmosphere.eu/) projects. Apart from directly contributing through data assimilation, satellite data is also used for the top-down quantification of emission sources and understanding of atmospheric processes, thus improving chemistry transport models. The OMI instrument, which was launched in July 2004, was the first instrument that combined daily global coverage with high spatial resolution of 13x24 km2 at nadir. The OMI data have attracted many new users and has resulted in several new applications. The TROPOMI instrument, planned for launch in late 2014, will be the first in a series of European satellite sensors dedicated for monitoring atmospheric composition changes in the timeframe 2015-2030. The TROPOMI instrument has a heritage to both OMI and SCIAMACHY. With a spatial resolution as high as 7x7 km2, higher signal-to-noise and extended spectral coverage, TROPOMI will provide exciting new information on the changing composition of the troposphere. The planned formation flying with the US afternoon NPP/JPSS satellites will enable important synergies, including the usage of high spatial resolution imager data for enhanced cloud clearing of the TROPOMI data. The availability of the morning MetOp (GOME-2 and IASI) measurements will provide complementary information on the diurnal variability. In this contribution an overview will be given of successes of OMI for air quality monitoring and research. In addition, the European satellite missions for atmospheric composition within the ESA/GMES Sentinel programme will be presented, with a focus on the TROPOMI instrument design and performance status.

  16. The growth of the oceanic boundary layer during the COARE intensive observational period: Large Eddy simulation results

    SciTech Connect

    Skyllingstad, E.D.; Wijesekera, H.W.; Gregg, M.C.

    1995-03-01

    A principal goal of the Tropical Ocean Global Atmosphere (TOGA) Coupled Ocean-Atmosphere Response Experiment (COARE) is to gain an understanding of the processes that control mixing in the upper 100 m of the western tropical Pacific warm pool. The warm pool is an important heat reservoir for the global ocean and is responsible for many of the observed climatic changes associated with El Nino/Southern Oscillation (ENSO) events. This water mass is highly sensitive to mixed-layer processes that are controlled by surface heat, salinity, and momentum fluxes. During most of the year, these fluxes are dominated by solar heating and occasional squalls that freshen the top of the mixed layer and force shallow mixing of about 10-20 m. From November to April, the usual weather pattern is frequently altered by westerly wind bursts that are forced by tropical cyclones and intraseasonal oscillations. These wind bursts generate a strong eastward surface current and can force mixing as deep as 100 m over a period of days. Observations from the intensive observation period (IOP) in COARE indicate that mixed-layer deepening is accompanied by strong turbulence dissipation at the mixed layer base. A short westerly wind burst occurred during the first leg of TOGA-COARE, and lasted about 4-5 days. During this period, the maximum winds were about 10 m s{sup -1}, and the resulting eastward surface flow was about 0.5 m s{sup -1}. The strength of this event was somewhat weaker than a typical westerly wind burst, but the mixed-layer structure and growth are similar to the more vigorous wind bursts discussed.

  17. The Art Show

    ERIC Educational Resources Information Center

    Scolarici, Alicia

    2004-01-01

    This article describes what once was thought to be impossible--a formal art show extravaganza at an elementary school with 1,000 students, a Department of Defense Dependent School (DODDS) located overseas, on RAF Lakenheath, England. The dream of this this event involved the transformation of the school cafeteria into an elegant art show

  18. PKS 2155-304 in July 2006: H.E.S.S. results and simultaneous multi-wavelength observations

    SciTech Connect

    Lenain, Jean-Philippe; Boisson, Catherine; Sol, Helne; Zech, Andreas; Benbow, Wystan; Buehler, Rolf; Costamante, Luigi; Raue, Martin; Giebels, Berrie; Superina, Giulia; Punch, Michael; Volpe, Francesca

    2008-12-24

    The high-frequency-peaked BL Lac PKS 2155-304 is one of the brightest and best-studied VHE {gamma}-ray sources in the southern hemisphere. The High Energy Stereoscopic System (H.E.S.S.) has monitored PKS 2155-304 in 2006 and a multi-wavelength campaign involving X-ray, optical and radio observatories was triggered by the detection of an active state in July 2006, followed by the detection of two extraordinary flares on July, 28th and 30th, with peak fluxes {approx}100 times the usual values. We present results from the spectral and flux variability analysis of the VHE and simultaneous X-ray observations with Chandra during the second flare, as well as the detailed evolution of the VHE flux of PKS 2155-304 observed by H.E.S.S. in 2006. A study of flux correlations in the different frequency ranges during the second flare and the adjacent nights is discussed. We also present an interpretation of the active state of PKS 2155-304 in the framework of synchrotron self-Compton emission.

  19. Temporal and vertical distribution of acidity and ionic composition in clouds - Comparison between modeling results and observations

    NASA Technical Reports Server (NTRS)

    Defelice, T. P.; Saxena, V. K.

    1990-01-01

    Cyclic temporal variations of pH and ionic concentration in sampled clouds which traversed the Mt. Mitchell State Park (North Carolina) site during the summers of 1986, 1987, and 1988 are reported. These clouds typically had a measured pH minimum during their initial and final stages. The cause of this basic cylic pattern is attributed to sampling at different vertical levels of the cloud. This is substantiated by visual observations made while sampling. The results also suggest that the measured pH patterns do not always exhibit minima during the formative and dissipative stages of the cloud, apparently in response to the underlying dynamical processes. The relationship between temporal pH measurements made at a stationary site to vertical cloud levels provides insights into the physical processes (e.g., nucleation scavenging near cloud base, dry air entrainment near cloud top) influencing the observed cloud-water chemistry on a real-time basis and would improve cloud chemistry models.

  20. The Greenwich Photo-heliographic Results (1874 - 1976): Summary of the Observations, Applications, Datasets, Definitions and Errors

    NASA Astrophysics Data System (ADS)

    Willis, D. M.; Coffey, H. E.; Henwood, R.; Erwin, E. H.; Hoyt, D. V.; Wild, M. N.; Denig, W. F.

    2013-11-01

    The measurements of sunspot positions and areas that were published initially by the Royal Observatory, Greenwich, and subsequently by the Royal Greenwich Observatory (RGO), as the Greenwich Photo-heliographic Results ( GPR), 1874 - 1976, exist in both printed and digital forms. These printed and digital sunspot datasets have been archived in various libraries and data centres. Unfortunately, however, typographic, systematic and isolated errors can be found in the various datasets. The purpose of the present paper is to begin the task of identifying and correcting these errors. In particular, the intention is to provide in one foundational paper all the necessary background information on the original solar observations, their various applications in scientific research, the format of the different digital datasets, the necessary definitions of the quantities measured, and the initial identification of errors in both the printed publications and the digital datasets. Two companion papers address the question of specific identifiable errors; namely, typographic errors in the printed publications, and both isolated and systematic errors in the digital datasets. The existence of two independently prepared digital datasets, which both contain information on sunspot positions and areas, makes it possible to outline a preliminary strategy for the development of an even more accurate digital dataset. Further work is in progress to generate an extremely reliable sunspot digital dataset, based on the programme of solar observations supported for more than a century by the Royal Observatory, Greenwich, and the Royal Greenwich Observatory. This improved dataset should be of value in many future scientific investigations.

  1. Modeling of the dust tail of comet C/2012 S1 (ISON) from the results of observations

    NASA Astrophysics Data System (ADS)

    Kharchuk, S. V.; Ivanova, O. V.; Korsun, P. P.; Kiselev, N. N.; Moskvitin, A. S.

    2015-09-01

    The results of the dynamic modeling of the process, that formed the dust tail of comet C/2012 S1 (ISON), are presented. The images of the comet were acquired with the 1-meter Zeiss-1000 telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences (SAO RAS). To construct the model of the dust tail, the trajectories of 50 million dust particles were traced. The distribution of brightness in the dust tail of the comet was reproduced in the model. According to our model investigations, the observed tail could be formed by dust particles with the sizes ranging from 0.5 to 16.6 µm and the escape velocities from 17 to 130 m/s; the power exponent of the distribution by radius is-2.5, and the maximum age of the dust particles having formed the cometary tail is 25 days. In the paper, the brightness of the comet at the moment of observations is also estimated, and the morphology of the cometary coma is analyzed with the use of digital filters.

  2. Arches showing UV flaring activity

    NASA Technical Reports Server (NTRS)

    Fontenla, J. M.

    1988-01-01

    The UVSP data obtained in the previous maximum activity cycle show the frequent appearance of flaring events in the UV. In many cases these flaring events are characterized by at least two footpoints which show compact impulsive non-simultaneous brightenings and a fainter but clearly observed arch developes between the footpoints. These arches and footpoints are observed in line corresponding to different temperatures, as Lyman alpha, N V, and C IV, and when observed above the limb display large Doppler shifts at some stages. The size of the arches can be larger than 20 arcsec.

  3. A description of the University of Illinois meteor radar system and some first results. [for upper atmospheric wave dynamics observation

    NASA Technical Reports Server (NTRS)

    Geller, M. A.; Bowhill, S. A.; Hess, G. C.

    1977-01-01

    A recently established meteor radar system for observing motions in the upper atmosphere is described, which features a peak transmitter power of 5 megawatts. This large peak power should allow a much greater number of wind determination during a fixed period of time than other meteor radar stations. The essential features of the range algorithm, two velocity algorithms, and the interferometer phase difference algorithm in use are described. A typical measured variation in the radial southward wind as a function of time of day based on data from all altitudes is shown as an example, and some results of spectral analysis of the data, yielding amplitude and phase variation with altitude for significant waves, is discussed.

  4. Results of the search for inspiraling compact star binaries from TAMA300's observation in 2000 2004

    NASA Astrophysics Data System (ADS)

    Akutsu, Tomomi; Akutsu, Tomotada; Ando, Masaki; Arai, Koji; Araya, Akito; Asada, Hideki; Aso, Youichi; Barton, Mark A.; Beyersdorf, Peter; Fujiki, Youhei; Fujimoto, Masa-Katsu; Fujita, Ryuichi; Fukushima, Mitsuhiro; Futamase, Toshifumi; Hamuro, Yusaku; Haruyama, Tomiyoshi; Hayakawa, Hideaki; Hayama, Kazuhiro; Heinzel, Gerhard; Horikoshi, Gen'Ichi; Iguchi, Hideo; Iida, Yukiyoshi; Ioka, Kunihito; Ishitsuka, Hideki; Kamikubota, Norihiko; Kanda, Nobuyuki; Kaneyama, Takaharu; Karasawa, Yoshikazu; Kasahara, Kunihiko; Kasai, Taketoshi; Katsuki, Mayu; Kawabe, Keita; Kawamura, Mari; Kawamura, Seiji; Kawashima, Nobuki; Kawazoe, Fumiko; Kojima, Yasufumi; Kokeyama, Keiko; Kondo, Kazuhiro; Kozai, Yoshihide; Kudoh, Hideaki; Kuroda, Kazuaki; Kuwabara, Takashi; Matsuda, Namio; Mio, Norikatsu; Miura, Kazuyuki; Miyakawa, Osamu; Miyama, Shoken; Miyoki, Shinji; Mizusawa, Hiromi; Moriwaki, Shigenori; Musha, Mitsuru; Nagano, Shigeo; Nagayama, Yoshitaka; Nakagawa, Ken'Ichi; Nakamura, Takashi; Nakano, Hiroyuki; Nakao, Ken-Ichi; Nishi, Yuhiko; Numata, Kenji; Ogawa, Yujiro; Ohashi, Masatake; Ohishi, Naoko; Okutomi, Akira; Oohara, Ken-Ichi; Otsuka, Shigemi; Sago, Norichika; Saito, Yoshio; Sakata, Shihori; Sasaki, Misao; Sato, Kouichi; Sato, Nobuaki; Sato, Shuichi; Sato, Youhei; Seki, Hidetsugu; Sekido, Aya; Seto, Naoki; Shibata, Masaru; Shinkai, Hisaaki; Shintomi, Takakazu; Soida, Kenji; Somiya, Kentaro; Suzuki, Toshikazu; Tagoshi, Hideyuki; Takahashi, Hirotaka; Takahashi, Ryutaro; Takamori, Akiteru; Takemoto, Shuzo; Takeno, Kohei; Tanaka, Takahiro; Taniguchi, Keisuke; Taniguchi, Shinsuke; Tanji, Toru; Tatsumi, Daisuke; Taylor, C. T.; Telada, Souichi; Tochikubo, Kuniharu; Tokunari, Masao; Tomaru, Takayuki; Tsubono, Kimio; Tsuda, Nobuhiro; Tsunesada, Yoshiki; Uchiyama, Takashi; Ueda, Akitoshi; Ueda, Ken-Ichi; Usui, Fumihiko; Waseda, Koichi; Watanabe, Yuko; Yakura, Hiromi; Yamamoto, Akira; Yamamoto, Kazuhiro; Yamazaki, Toshitaka; Yanagi, Yuriko; Yoda, Tatsuo; Yokoyama, Jun'Ichi; Yoshida, Tatsuru; Zhu, Zong-Hong

    2006-12-01

    We analyze the data of the TAMA300 detector to search for gravitational waves from inspiraling compact star binaries with masses of the component stars in the range 1M? 3M?. In this analysis, 2705 hours of data, taken during the years 2000 2004, are used for the event search. We combine the results of different observation runs, and obtain a single upper limit on the rate of the coalescence of compact binaries in our Galaxy of 20 per year at a 90% confidence level. In this upper limit, the effects of various systematic errors such as the uncertainty of the background estimation and the calibration of the detectors sensitivity are included.

  5. The VLA Low Band Project: Early Commissioning Results and Vision for a Primary Focus-based Commensal Observing system

    NASA Astrophysics Data System (ADS)

    Kassim, Namir E.; Clarke, T. E.; Hicks, B.; Peters, W. M.; Wilson, T. L.; Cutchin, S.; Owen, F. N.; Perley, R. A.; Durand, S.; Kutz, C.; Harden, P.; Intema, H.; Brisken, W.; Subrahmanyan, R.; Taylor, G. B.; Lazio, T. J.

    2013-01-01

    We present an update on the Jansky Very Large Array Low Band (VLA-LB) project, currently undergoing scientific commissioning and expected to be fully available in 2013. VLA-LB is a joint NRL and NRAO initiative to equip the VLA with broadband low frequency receivers that cover the spectrum between 66 and 470 MHz. The current system can already access the 66 to 86 MHz and 230 to 436 MHz sub-bands by working with existing 74 and 330 MHz feeds, respectively. The bandwidth at 74 MHz will increase by more than an order of magnitude while the 330 MHz bandwidth increases by approximately a factor of 6. The improved bandwidth and system temperature, coupled with the power of the WIDAR correlator, promise significantly enhanced performance compared to past VLA capabilities. Early commissioning results at “P band” (330 MHz) with a handful of antennas accessing the larger bandwidth indicate sensitivity rivaling that of the legacy 27-antenna, narrow-band old VLA capability. New feeds that can exploit a larger fraction of the available receiver bandwidth are being explored. While VLA-LB is useful as a conventional system, we are looking to enhance its power by leveraging the VLA’s capability to detect radiation at its prime and Cassegrain foci simultaneously. The ability to observe with more than one band in parallel is a powerful multiplier of a telescope’s function, and many instruments (e.g. the GMRT, WSRT and VLA) offer this. A variant is being explored for VLA-LB: observing from the prime focus during all normal Cassegrain observations. This proposed VLA-LB commensal system would piggyback normal VLA observing time to survey at low frequencies with relatively large field of views. Shared fields with other multi-beaming, dipole-based arrays that view the same sky with the VLA, e.g. the first station of the Long Wavelength Array (LWA1), would be possible. The collected data will be assembled into a database of spectra and wide-field images, suitable for studies of individual objects as well as searches for transients and high redshift spectral features (eg. HI absorption or OH mega-masers). We describe how the VLA-LB commensal system might be implemented, and explore early ideas for its scientific promise.

  6. Validation of first chemistry mode retrieval results from the new limb-imaging FTS GLORIA with correlative MIPAS-STR observations

    NASA Astrophysics Data System (ADS)

    Woiwode, W.; Sumińska-Ebersoldt, O.; Oelhaf, H.; Höpfner, M.; Belyaev, G. V.; Ebersoldt, A.; Friedl-Vallon, F.; Grooß, J.-U.; Gulde, T.; Kaufmann, M.; Kleinert, A.; Krämer, M.; Kretschmer, E.; Kulessa, T.; Maucher, G.; Neubert, T.; Piesch, C.; Preusse, P.; Riese, M.; Rongen, H.; Sartorius, C.; Schardt, G.; Schönfeld, A.; Schuettemeyer, D.; Sha, M. K.; Stroh, F.; Ungermann, J.; Volk, C. M.; Orphal, J.

    2015-06-01

    We report first chemistry mode retrieval results from the new airborne limb-imaging infrared FTS (Fourier transform spectrometer) GLORIA (Gimballed Limb Observer for Radiance Imaging of the Atmosphere) and comparisons with observations by the conventional airborne limb-scanning infrared FTS MIPAS-STR (Michelson Interferometer for Passive Atmospheric Sounding - STRatospheric aircraft). For GLORIA, the flights aboard the high-altitude research aircraft M55 Geophysica during the ESSenCe campaign (ESa Sounder Campaign 2011) were the very first in field deployment after several years of development. The simultaneous observations of GLORIA and MIPAS-STR during the flight on 16 December 2011 inside the polar vortex and under conditions of optically partially transparent polar stratospheric clouds (PSCs) provided us the first opportunity to compare the observations by two different infrared FTS generations directly. We validate the GLORIA results with MIPAS-STR based on the lower vertical resolution of MIPAS-STR and compare the vertical resolutions of the instruments derived from their averaging kernels. The retrieval results of temperature, HNO3, O3, H2O, CFC-11 and CFC-12 show reasonable agreement of GLORIA with MIPAS-STR and collocated in situ observations. For the horizontally binned hyperspectral limb images, the GLORIA sampling outnumbered the horizontal cross-track sampling of MIPAS-STR by up to 1 order of magnitude. Depending on the target parameter, typical vertical resolutions of 0.5 to 2.0 km were obtained for GLORIA and are typically a factor of 2 to 4 better compared to MIPAS-STR. While the improvement of the performance, characterization and data processing of GLORIA are the subject of ongoing work, the presented first results already demonstrate the considerable gain in sampling and vertical resolution achieved with GLORIA.

  7. Results of the magnetic field measurements of CP stars carried out with the Russian 6-m telescope. II. Observations in 2008

    NASA Astrophysics Data System (ADS)

    Romanyuk, I. I.; Semenko, E. A.; Kudryavtsev, D. O.

    2015-10-01

    We present the results of the magnetic field measurements of 37 chemically peculiar and 4 normal main sequence stars using circularly polarized spectra obtained in 2008 with a Zeeman analyzer on the Main Stellar Spectrograph (MSS) of the Russian 6-m telescope (BTA). Four new magnetic stars have been discovered (HD25999, HD35100, HD96237, and HD279021), the presence of a field was suspected in two stars (HD2887 and BD-122366), 16 previously known CP stars were continued to be monitored to study their fields. The results of the longitudinal magnetic field B e measurements show that in stars with narrow spectral lines, systematic errors in B e determination do not exceed 10-20 G, which is within the statistical error. Our study of stars with reliable phase curves of the longitudinal field B e show that there are no instrumental effects which can distort the observations.

  8. A Holographic Road Show.

    ERIC Educational Resources Information Center

    Kirkpatrick, Larry D.; Rugheimer, Mac

    1979-01-01

    Describes the viewing sessions and the holograms of a holographic road show. The traveling exhibits, believed to stimulate interest in physics, include a wide variety of holograms and demonstrate several physical principles. (GA)

  9. Effect of different transport observations on inverse modeling results: case study of a long-term groundwater tracer test monitored at high resolution

    PubMed Central

    Rasa, Ehsan; Foglia, Laura; Mackay, Douglas M.; Scow, Kate M.

    2014-01-01

    Conservative tracer experiments can provide information useful for characterizing various subsurface transport properties. This study examines the effectiveness of three different types of transport observations for sensitivity analysis and parameter estimation of a three-dimensional site-specific groundwater flow and transport model: conservative tracer breakthrough curves (BTCs), first temporal moments of BTCs (m1), and tracer cumulative mass discharge (Md) through control planes combined with hydraulic head observations (h). High-resolution data obtained from a 410-day controlled field experiment at Vandenberg Air Force Base, California (USA), have been used. In this experiment, bromide was injected to create two adjacent plumes monitored at six different transects (perpendicular to groundwater flow) with a total of 162 monitoring wells. A total of 133 different observations of transient hydraulic head, 1,158 of BTC concentration, 23 of first moment, and 36 of mass discharge were used for sensitivity analysis and parameter estimation of nine flow and transport parameters. The importance of each group of transport observations in estimating these parameters was evaluated using sensitivity analysis, and five out of nine parameters were calibrated against these data. Results showed the advantages of using temporal moment of conservative tracer BTCs and mass discharge as observations for inverse modeling. PMID:24672283

  10. Effect of different transport observations on inverse modeling results: case study of a long-term groundwater tracer test monitored at high resolution.