Basics of SCI Rehabilitation

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Full Text Available ... Spinal Cord Injuries Video Library SCI Medical Experts People Living with SCI Personal Experiences by Topic Resources ... Spinal Cord Injuries Video Library SCI Medical Experts People Living with SCI Personal Experiences by Topic Resources ...

SciServer Compute brings Analysis to Big Data in the Cloud

Science.gov (United States)

Raddick, Jordan; Medvedev, Dmitry; Lemson, Gerard; Souter, Barbara

2016-06-01

SciServer Compute uses Jupyter Notebooks running within server-side Docker containers attached to big data collections to bring advanced analysis to big data "in the cloud." SciServer Compute is a component in the SciServer Big-Data ecosystem under development at JHU, which will provide a stable, reproducible, sharable virtual research environment.SciServer builds on the popular CasJobs and SkyServer systems that made the Sloan Digital Sky Survey (SDSS) archive one of the most-used astronomical instruments. SciServer extends those systems with server-side computational capabilities and very large scratch storage space, and further extends their functions to a range of other scientific disciplines.Although big datasets like SDSS have revolutionized astronomy research, for further analysis, users are still restricted to downloading the selected data sets locally - but increasing data sizes make this local approach impractical. Instead, researchers need online tools that are co-located with data in a virtual research environment, enabling them to bring their analysis to the data.SciServer supports this using the popular Jupyter notebooks, which allow users to write their own Python and R scripts and execute them on the server with the data (extensions to Matlab and other languages are planned). We have written special-purpose libraries that enable querying the databases and other persistent datasets. Intermediate results can be stored in large scratch space (hundreds of TBs) and analyzed directly from within Python or R with state-of-the-art visualization and machine learning libraries. Users can store science-ready results in their permanent allocation on SciDrive, a Dropbox-like system for sharing and publishing files. Communication between the various components of the SciServer system is managed through SciServer‘s new Single Sign-on Portal.We have created a number of demos to illustrate the capabilities of SciServer Compute, including Python and R scripts

The Fulldome Curriculum for the Spitz SciDome Digital Planetarium: Volume 2

Science.gov (United States)

Bradstreet, David H.; Sanders, S. J.; Huggins, S.

2014-01-01

The Spitz Fulldome Curriculum (FDC) for the SciDome digital planetarium ushered in a new and innovative way to present astronomical pedagogy via its use of the unique teaching attributes of the digital planetarium. In the case of the FDC, which uses the ubiquitous Starry Night planetarium software as its driving engine, these engaging and novel teaching techniques have also been made usable to desktop computers and flat-screen video projectors for classroom use. Volume 2 of the FDC introduces exciting new classes and mini-lessons to further enlighten and invigorate students as they struggle with often difficult three dimensional astronomical concepts. Additionally, other topics with related astronomical ties have been created to integrate history into planetarium presentations. One of the strongest advantages of the SciDome is its use of Starry Night as its astronomical engine. With it students can create their own astronomical configurations in the computer lab or at home, using the PC or Mac version. They can then simply load their creations onto the SciDome planetarium system and display them for their classmates on the dome. This poster will discuss and illustrate some of the new content that has been developed for Volume 2. Topics covered in Volume 2 include eclipses, plotting planet locations on a curtate orbit chart by observing their positions in the sky, time and timekeeping (including sidereal day, hour angles, sidereal time, LAST, LMST, time zones and the International Date Line), teaching to the Boy Scout Merit Badge requirements, plotting scale analemmas on the surface of planets and interpreting them, precession, astronomical events in revolutionary Boston, the Lincoln Almanac Trial, eclipsing binaries, lunar librations, a trip through the universe, watching the speed of light move in real time, stellar sizes and the Milky Way.

Origins and Destinations: Tracking Planet Composition through Planet Formation Simulations

Science.gov (United States)

Chance, Quadry; Ballard, Sarah

2018-01-01

There are now several thousand confirmed exoplanets, a number which far exceeds our resources to study them all in detail. In particular, planets around M dwarfs provide the best opportunity for in-depth study of their atmospheres by telescopes in the near future. The question of which M dwarf planets most merit follow-up resources is a pressing one, given that NASA’s TESS mission will soon find hundreds of such planets orbiting stars bright enough for both ground and spaced-based follow-up.Our work aims to predict the approximate composition of planets around these stars through n-body simulations of the last stage of planet formation. With a variety of initial disk conditions, we investigate how the relative abundances of both refractory and volatile compounds in the primordial planetesimals are mapped to the final planet outcomes. These predictions can serve to provide a basis for making an educated guess about (a) which planets to observe with precious resources like JWST and (b) how to identify them based on dynamical clues.

DETECTABILITY OF FREE FLOATING PLANETS IN OPEN CLUSTERS WITH THE JAMES WEBB SPACE TELESCOPE

Energy Technology Data Exchange (ETDEWEB)

Pacucci, Fabio; Ferrara, Andrea [Scuola Normale Superiore, Piazza dei Cavalieri 7, I-56126 Pisa (Italy); D' Onghia, Elena [University of Wisconsin, 475 Charter St., Madison, WI 53706 (United States)

2013-12-01

Recent observations have shown the presence of extra-solar planets in Galactic open stellar clusters, such as in Praesepe (M44). These systems provide a favorable environment for planetary formation due to the high heavy-element content exhibited by the majority of their population. The large stellar density, and corresponding high close-encounter event rate, may induce strong perturbations of planetary orbits with large semimajor axes. Here we present a set of N-body simulations implementing a novel scheme to treat the tidal effects of external stellar perturbers on planetary orbit eccentricity and inclination. By simulating five nearby open clusters, we determine the rate of occurrence of bodies extracted from their parent stellar system by quasi-impulsive tidal interactions. We find that the specific free-floating planet production rate N-dot {sub o} (total number of free-floating planets per unit of time, normalized by the total number of stars), is proportional to the stellar density ρ{sub *} of the cluster: N-dot {sub o}=αρ{sub ⋆}, with α = (23 ± 5) × 10{sup –6} pc{sup 3} Myr{sup –1}. For the Pleiades (M45), we predict that ∼26% of stars should have lost their planets. This raises the exciting possibility of directly observing these wandering planets with the James Webb Space Telescope in the near-infrared band. Assuming a surface temperature for the planet of ∼500 K, a free-floating planet of Jupiter size inside the Pleiades would have a specific flux of F {sub ν} (4.4 μm) ≈4 × 10{sup 2} nJy, which would lead to a very clear detection (S/N ∼ 100) in only one hour of integration.

Stability of Multi-Planet Systems in the Alpha Centauri System

Science.gov (United States)

Lissauer, Jack J.

2017-01-01

We evaluate the extent of the regions within the alpha Centauri AB star system where small planets are able to orbit for billion-year timescales (Quarles & Lissauer 2016, Astron. J. 151, 111), as well as how closely-spaced planetary orbits can be within those regions in which individual planets can survive. Although individual planets on low inclination, low eccentricity, orbits can survive throughout the habitable zones of both stars, perturbations from the companion star imply that the spacing of planets in multi-planet systems within the habitable zones of each star must be significantly larger than the spacing of similar multi-planet systems orbiting single stars in order to be long-lived. Because the binary companion induces a forced eccentricity upon the orbits of planets in orbit around either star, appropriately-aligned circumstellar orbits with small initial eccentricities are stable to slightly larger initial semimajor axes than are initially circular orbits. Initial eccentricities close to forced eccentricities can have a much larger affect on how closely planetary orbits can be spaced, and therefore on how many planets may remain in the habitable zones, although the required spacing remains significantly higher than for planets orbiting single stars.

Characterizing Cool Giant Planets in Reflected Light

Science.gov (United States)

Marley, Mark

2016-01-01

While the James Webb Space Telescope will detect and characterize extrasolar planets by transit and direct imaging, a new generation of telescopes will be required to detect and characterize extrasolar planets by reflected light imaging. NASA's WFIRST space telescope, now in development, will image dozens of cool giant planets at optical wavelengths and will obtain spectra for several of the best and brightest targets. This mission will pave the way for the detection and characterization of terrestrial planets by the planned LUVOIR or HabEx space telescopes. In my presentation I will discuss the challenges that arise in the interpretation of direct imaging data and present the results of our group's effort to develop methods for maximizing the science yield from these planned missions.

Homes for extraterrestrial life: extrasolar planets.

Science.gov (United States)

Latham, D W

2001-12-01

Astronomers are now discovering giant planets orbiting other stars like the sun by the dozens. But none of these appears to be a small rocky planet like the earth, and thus these planets are unlikely to be capable of supporting life as we know it. The recent discovery of a system of three planets is especially significant because it supports the speculation that planetary systems, as opposed to single orbiting planets, may be common. Our ability to detect extrasolar planets will continue to improve, and space missions now in development should be able to detect earth-like planets.

Basics of SCI Rehabilitation

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Full Text Available ... Injury Facts and Figures Care and Treatment After SCI Spinal Cord Injury Rehabilitation Pediatric Spinal Cord Injuries Video Library SCI Medical Experts People Living with SCI Personal Experiences ...

Liquid Chromatography Applied to Space System

Science.gov (United States)

Poinot, Pauline; Chazalnoel, Pascale; Geffroy, Claude; Sternberg, Robert; Carbonnier, Benjamin

Viking results. Proc Natl Acad Sci U.S.A 103:89-94 Bada JL, Ehrenfreund P, Grunthaner F et al (2008) Urey: Mars Organic and Oxidant Detector. Space Sci Rev 135: 269-279. doi: 10.1007/s11214-007-9213-3 doi_10.1073_pnas.0604210103 Schulze-Makuch D, Head JN, Houtkooper JM et al (2012) The Biological Oxidant and Life Detection (BOLD) mission: A proposal for a mission to Mars. Planet Space Sci 67:57-69. doi: 10.1016/j.pss.2012.03.008 Parro V, Rodríguez-Manfredi JA, Briones C et al (2005) Instrument development to search for biomarkers on mars: Terrestrial acidophile, iron-powered chemolithoautotrophic communities as model systems. Planet Space Sci 53:729-737. doi:10.1016/j.pss.2005.02.003 Sims MR, Cullen DC, Rix CS et al (2012) Development status of the life marker chip instrument for ExoMars. Planet Space Sci 72:129-137. doi:10.1016/j.pss.2012.04.007

Scattering of exocomets by a planet chain: exozodi levels and the delivery of cometary material to inner planets

Science.gov (United States)

Marino, Sebastian; Bonsor, Amy; Wyatt, Mark C.; Kral, Quentin

2018-06-01

Exocomets scattered by planets have been invoked to explain observations in multiple contexts, including the frequently found near- and mid-infrared excess around nearby stars arising from exozodiacal dust. Here we investigate how the process of inward scattering of comets originating in an outer belt, is affected by the architecture of a planetary system, to determine whether this could lead to observable exozodi levels or deliver volatiles to inner planets. Using N-body simulations, we model systems with different planet mass and orbital spacing distributions in the 1-50 AU region. We find that tightly packed (Δap planets are the most efficient at delivering material to exozodi regions (5-7% of scattered exocomets end up within 0.5 AU at some point), although the exozodi levels do not vary by more than a factor of ˜7 for the architectures studied here. We suggest that emission from scattered dusty material in between the planets could provide a potential test for this delivery mechanism. We show that the surface density of scattered material can vary by two orders of magnitude (being highest for systems of low mass planets with medium spacing), whilst the exozodi delivery rate stays roughly constant, and that future instruments such as JWST could detect it. In fact for η Corvi, the current Herschel upper limit rules our the scattering scenario by a chain of ≲30 M⊕ planets. Finally, we show that exocomets could be efficient at delivering cometary material to inner planets (0.1-1% of scattered comets are accreted per inner planet). Overall, the best systems at delivering comets to inner planets are the ones that have low mass outer planets and medium spacing (˜20RH, m).

SciSpark: Highly Interactive and Scalable Model Evaluation and Climate Metrics for Scientific Data and Analysis

Data.gov (United States)

National Aeronautics and Space Administration — We will construct SciSpark, a scalable system for interactive model evaluation and for the rapid development of climate metrics and analyses. SciSpark directly...

Blue limits of the Blue Planet : An exploratory analysis of safe operating spaces for human water use under deep uncertainty

NARCIS (Netherlands)

Kwakkel, J.H.; Timmermans, J.S.

2012-01-01

In the Nature article ‘A safe operating space for humanity’, Rockström et al. (2009) introduce the concept of a safe operating space for humanity. A safe operating space is the space for human activities that will not push the planet out of the ‘Holocene state’ that has seen human civilizations

Sex and Fertility After SCI

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Full Text Available ... Cord Injury Rehabilitation Pediatric Spinal Cord Injuries Video Library SCI Medical Experts People Living with SCI Personal ... Cord Injury Rehabilitation Pediatric Spinal Cord Injuries Video Library SCI Medical Experts People Living with SCI Personal ...

Sex and Fertility After SCI

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Full Text Available ... Spinal Cord Injuries Video Library SCI Medical Experts People Living with SCI Personal Experiences by Topic Resources ... Spinal Cord Injuries Video Library SCI Medical Experts People Living with SCI Personal Experiences by Topic Resources ...

IMPACT OF η{sub Earth} ON THE CAPABILITIES OF AFFORDABLE SPACE MISSIONS TO DETECT BIOSIGNATURES ON EXTRASOLAR PLANETS

Energy Technology Data Exchange (ETDEWEB)

Léger, Alain [IAS, Univ. Paris-Sud, Orsay (France); Defrère, Denis [Steward Observatory, Department of Astronomy, University of Arizona, 933 N. Cherry Ave, Tucson, AZ 85721 (United States); Malbet, Fabien [UJF-Grenoble 1/CNRS-INSU, Institut de Planétologie et d’Astrophysique de Grenoble (IPAG), UMR 5274, BP 53, F-38041 Grenoble cedex 9 (France); Labadie, Lucas [I. Physikalisches Institut der Universität zu Köln, Zülpicher Str. 77, D-50937 Cologne (Germany); Absil, Olivier, E-mail: Alain.Leger@ias.u-psud.fr [Département d’Astrophysique, Géophysique and Océanographie, Université de Liège, 17 Allée du Six Août, B-4000 Liège (Belgium)

2015-08-01

We present an analytic model to estimate the capabilities of space missions dedicated to the search for biosignatures in the atmosphere of rocky planets located in the habitable zone of nearby stars. Relations between performance and mission parameters, such as mirror diameter, distance to targets, and radius of planets, are obtained. Two types of instruments are considered: coronagraphs observing in the visible, and nulling interferometers in the thermal infrared. Missions considered are: single-pupil coronagraphs with a 2.4 m primary mirror, and formation-flying interferometers with 4 × 0.75 m collecting mirrors. The numbers of accessible planets are calculated as a function of η{sub Earth}. When Kepler gives its final estimation for η{sub Earth}, the model will permit a precise assessment of the potential of each instrument. Based on current estimations, η{sub Earth} = 10% around FGK stars and 50% around M stars, the coronagraph could study in spectroscopy only ∼1.5 relevant planets, and the interferometer ∼14.0. These numbers are obtained under the major hypothesis that the exozodiacal light around the target stars is low enough for each instrument. In both cases, a prior detection of planets is assumed and a target list established. For the long-term future, building both types of spectroscopic instruments, and using them on the same targets, will be the optimal solution because they provide complementary information. But as a first affordable space mission, the interferometer looks the more promising in terms of biosignature harvest.

The Fulldome Curriculum for the Spitz SciDome Digital Planetarium: A New Age for Planetarium Education

Science.gov (United States)

Bradstreet, David H.; Huggins, S. L.

2010-01-01

Astronomy education received a huge boost from the Space Program in the 1960's and early 1970's as evidenced by a large increase in school planetariums built nationwide at that time. But with the waning of manned explorations so also went the push for astronomy in the schools, and many school planetariums are underutilized or not used at all. This poster will discuss and illustrate some of the new Fulldome Curriculum that has been developed specifically for the Spitz SciDome digital planetarium powered by Starry Night. It is now possible to teach astronomical concepts in new and exciting ways and present topics that were extremely difficult to convey to lay audiences in the past. One of the strongest advantages of the SciDome is that, since it uses Starry Night as its astronomical engine, students can create their own astronomical configurations in the computer lab or at home using the PC or Mac version and then simply load them onto the SciDome planetarium system and display them for the class on the dome. Additionally, the instructor can create artificial bodies to pose "What if” scenarios, for example, "What would the Moon look like if it didn't rotate synchronously?", or "What would the analemma look like if the Earth's orbit were circular and not an ellipse?" Topics covered in the series include The Moon, Seasons, Coordinate Systems, Roemer's Method of Measuring the Speed of Light, Analemmas in the Solar System, Precession, Mimas and the Cassini Division, Halley's Comet in 1910, Dog Days, Galactic Distributions of Celestial Bodies, Retrograde Paths of Mars, Mercury's Orbit and the Length of the Mercurian Day, Altitude of the North Celestial Pole, Why Polaris Appears Mostly Stationary, Circumpolar Contellations, Planet Definition, Scale of the Solar System, Stonehenge, The Changing Aspect of Saturn's Appearance and Scorpio's Claws.

YOUNG SOLAR SYSTEM's FIFTH GIANT PLANET?

International Nuclear Information System (INIS)

Nesvorný, David

2011-01-01

Studies of solar system formation suggest that the solar system's giant planets formed and migrated in the protoplanetary disk to reach the resonant orbits with all planets inside ∼15 AU from the Sun. After the gas disk's dispersal, Uranus and Neptune were likely scattered by the gas giants, and approached their current orbits while dispersing the transplanetary disk of planetesimals, whose remains survived to this time in the region known as the Kuiper Belt. Here we performed N-body integrations of the scattering phase between giant planets in an attempt to determine which initial states are plausible. We found that the dynamical simulations starting with a resonant system of four giant planets have a low success rate in matching the present orbits of giant planets and various other constraints (e.g., survival of the terrestrial planets). The dynamical evolution is typically too violent, if Jupiter and Saturn start in the 3:2 resonance, and leads to final systems with fewer than four planets. Several initial states stand out in that they show a relatively large likelihood of success in matching the constraints. Some of the statistically best results were obtained when assuming that the solar system initially had five giant planets and one ice giant, with the mass comparable to that of Uranus and Neptune, and which was ejected to interstellar space by Jupiter. This possibility appears to be conceivable in view of the recent discovery of a large number of free-floating planets in interstellar space, which indicates that planet ejection should be common.

Young Solar System's Fifth Giant Planet?

Science.gov (United States)

Nesvorný, David

2011-12-01

Studies of solar system formation suggest that the solar system's giant planets formed and migrated in the protoplanetary disk to reach the resonant orbits with all planets inside ~15 AU from the Sun. After the gas disk's dispersal, Uranus and Neptune were likely scattered by the gas giants, and approached their current orbits while dispersing the transplanetary disk of planetesimals, whose remains survived to this time in the region known as the Kuiper Belt. Here we performed N-body integrations of the scattering phase between giant planets in an attempt to determine which initial states are plausible. We found that the dynamical simulations starting with a resonant system of four giant planets have a low success rate in matching the present orbits of giant planets and various other constraints (e.g., survival of the terrestrial planets). The dynamical evolution is typically too violent, if Jupiter and Saturn start in the 3:2 resonance, and leads to final systems with fewer than four planets. Several initial states stand out in that they show a relatively large likelihood of success in matching the constraints. Some of the statistically best results were obtained when assuming that the solar system initially had five giant planets and one ice giant, with the mass comparable to that of Uranus and Neptune, and which was ejected to interstellar space by Jupiter. This possibility appears to be conceivable in view of the recent discovery of a large number of free-floating planets in interstellar space, which indicates that planet ejection should be common.

www.elearnSCI.org

DEFF Research Database (Denmark)

Chhabra, H S; Harvey, Lee; Muldoon, S

2013-01-01

OBJECTIVE: To develop a web-based educational resource for health professionals responsible for the management of spinal cord injury (SCI). The resource:www.elearnSCI.org is comprised of seven learning modules, each subdivided into various submodules. Six of the seven modules address the educatio......OBJECTIVE: To develop a web-based educational resource for health professionals responsible for the management of spinal cord injury (SCI). The resource:www.elearnSCI.org is comprised of seven learning modules, each subdivided into various submodules. Six of the seven modules address...... the educational needs of all disciplines involved in comprehensive SCI management. The seventh module addresses prevention of SCI. Each submodule includes an overview, activities, self-assessment questions and references. DEVELOPMENT OF THE RESOURCE: Three hundred and thirty-two experts from The International...... Spinal Cord Society (ISCoS) and various affiliated societies from 36 countries were involved in developing the resource through 28 subcommittees. The content of each submodule was reviewed and approved by the Education and Scientific Committees of ISCoS and finally by an Editorial Committee of 23 experts...

Sex and Fertility After SCI

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The planet Mercury (1971)

Science.gov (United States)

1972-01-01

The physical properties of the planet Mercury, its surface, and atmosphere are presented for space vehicle design criteria. The mass, dimensions, mean density, and orbital and rotational motions are described. The gravity field, magnetic field, electromagnetic radiation, and charged particles in the planet's orbit are discussed. Atmospheric pressure, temperature, and composition data are given along with the surface composition, soil mechanical properties, and topography, and the surface electromagnetic and temperature properties.

PLANET TOPERS: Planets, Tracing the Transfer, Origin, Preservation, and Evolution of their ReservoirS.

Science.gov (United States)

Dehant, V; Asael, D; Baland, R M; Baludikay, B K; Beghin, J; Belza, J; Beuthe, M; Breuer, D; Chernonozhkin, S; Claeys, Ph; Cornet, Y; Cornet, L; Coyette, A; Debaille, V; Delvigne, C; Deproost, M H; De WInter, N; Duchemin, C; El Atrassi, F; François, C; De Keyser, J; Gillmann, C; Gloesener, E; Goderis, S; Hidaka, Y; Höning, D; Huber, M; Hublet, G; Javaux, E J; Karatekin, Ö; Kodolanyi, J; Revilla, L Lobo; Maes, L; Maggiolo, R; Mattielli, N; Maurice, M; McKibbin, S; Morschhauser, A; Neumann, W; Noack, L; Pham, L B S; Pittarello, L; Plesa, A C; Rivoldini, A; Robert, S; Rosenblatt, P; Spohn, T; Storme, J -Y; Tosi, N; Trinh, A; Valdes, M; Vandaele, A C; Vanhaecke, F; Van Hoolst, T; Van Roosbroek, N; Wilquet, V; Yseboodt, M

2016-11-01

The Interuniversity Attraction Pole (IAP) 'PLANET TOPERS' (Planets: Tracing the Transfer, Origin, Preservation, and Evolution of their Reservoirs) addresses the fundamental understanding of the thermal and compositional evolution of the different reservoirs of planetary bodies (core, mantle, crust, atmosphere, hydrosphere, cryosphere, and space) considering interactions and feedback mechanisms. Here we present the first results after 2 years of project work.

Preface: SciDAC 2007

Science.gov (United States)

Keyes, David E.

2007-09-01

archive reflects the philosophy of the SciDAC program, which was introduced as a collaboration of all of the program offices in the Office of Science of the U.S. Department of Energy (DOE) in Fall 2001 and was renewed for a second period of five years in Fall 2006, with additional support in certain areas from the DOE's National Nuclear Security Administration (NNSA) and the U.S. National Science Foundation (NSF). All of the projects in the SciDAC portfolio were represented at the conference and most are captured in this volume. In addition, the Organizing Committee incorporated into the technical program a number of computational science highlights from outside of SciDAC, and, indeed, from outside of the United States. As implied by the title, scientific discovery is the driving deliverable of the SciDAC program, spanning the full range of the DOE Office of Science: accelerator design, astrophysics, chemistry and materials science, climate science, combustion, life science, nuclear physics, plasma physics, and subsurface physics. As articulated in the eponymous report that launched SciDAC, the computational challenges of these diverse areas are remarkably common. Each is profoundly multiscale in space and time and therefore continues to benefit at any margin from access to the largest and fastest computers available. Optimality of representation and execution requires adaptive, scalable mathematical algorithms in both continuous (geometrically complex domain) and discrete (mesh and graph) aspects. Programmability and performance optimality require software environments that both manage the intricate details of the underlying hardware and abstract them for scientific users. Running effectively on remote specialized hardware requires transparent workflow systems. Comprehending the petascale data sets generated in such simulations requires automated tools for data exploration and visualization. Archiving and sharing access to this data within the inevitably distributed

Planets for Man

National Research Council Canada - National Science Library

Dole, Stephen; Asimov, Isaac

2007-01-01

"Planets for Man" was written at the height of the space race, a few years before the first moon landing, when it was assumed that in the not-too-distant future human beings "will be able to travel...

Wandering stars about planets and exo-planets : an introductory notebook

CERN Document Server

Cole, George H A

2006-01-01

The space vehicle spectaculars of recent years have been revealing the full scope and beauty of our own solar system but have also shown that a growing number of other stars too have planetary bodies orbiting around them. The study of these systems is just beginning. It seems that our galaxy contains untold numbers of planets, and presumably other galaxies will be similar to our own. Our solar system contains life, on Earth: do others as well? Such questions excite modern planetary scientists and astro-biologists. This situation is a far cry from ancient times when the five planets that can be

Early Critical Care Decisions and Outcomes after SCI: Track-SCI

Science.gov (United States)

2017-09-01

injury represented grade 3 injury with super- imposed discrete foci of intramedullary T2 hypointensity attributed to the presence of macroscopic...Principal component analysis: a review and recent developments. Philos Trans A Math Phys Eng Sci 2016;374: 20150202 CrossRef Medline 33. Linting M...recommendations for acute SCI.15 Earlier in the course of this patient population, high-dose methylprednisolone was used at the discretion of the treating spine

Planet logy : Towards Comparative Planet logy beyond the Solar Earth System

Science.gov (United States)

Khan, A. H.

2011-10-01

Today Scenario planet logy is a very important concept because now days the scientific research finding new and new planets and our work's range becoming too long. In the previous study shows about 10-12 years the research of planet logy now has changed . Few years ago we was talking about Sun planet, Earth planet , Moon ,Mars Jupiter & Venus etc. included but now the time has totally changed the recent studies showed that mono lakes California find the arsenic food use by micro organism that show that our study is very tiny as compare to planet long areas .We have very well known that arsenic is the toxic agent's and the toxic agent's present in the lakes and micro organism developing and life going on it's a unbelievable point for us but nature always play a magical games. In few years ago Aliens was the story no one believe the Aliens origin but now the aliens showed catch by our space craft and shuttle and every one believe that Aliens origin but at the moment's I would like to mention one point's that we have too more work required because our planet logy has a vast field. Most of the time our scientific mission shows that this planet found liquid oxygen ,this planet found hydrogen .I would like to clear that point's that all planet logy depend in to the chemical and these chemical gave the indication of the life but we are not abele to developed the adaptation according to the micro organism . Planet logy compare before study shows that Sun it's a combination of the various gases combination surrounded in a round form and now the central Sun Planets ,moons ,comets and asteroids In other word we can say that Or Sun has a wide range of the physical and Chemical properties in the after the development we can say that all chemical and physical property engaged with a certain environment and form a various contains like asteroids, moon, Comets etc. Few studies shows that other planet life affected to the out living planet .We can assure with the example the life

Basics of SCI Rehabilitation

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Basics of SCI Rehabilitation

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Basics of SCI Rehabilitation

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Basics of SCI Rehabilitation

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Basics of SCI Rehabilitation

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Basics of SCI Rehabilitation

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Basics of SCI Rehabilitation

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Planets in a Room

Science.gov (United States)

Giacomini, l.; Aloisi, F.; De Angelis, I.

2017-09-01

Teaching planetary science using a spherical projector to show the planets' surfaces is a very effective but usually very expensive idea. Whatsmore, it usually assumes the availability of a dedicated space and a trained user. "Planets in a room" is a prototypal low cost version of a small, spherical projector that teachers, museum, planetary scientists and other individuals can easily build and use on their own, to show and teach the planets The project of "Planets in a Room" was made by the italian non-profit association Speak Science with the collaboration of INAF-IAPS of Rome and the Roma Tre University (Dipartimento di Matematica e Fisica). This proposal was funded by the Europlanet Outreach Funding Scheme in 2016. "Planets in a room" will be presented during EPSC 2017 to give birth to the second phase of the project, when the outreach and research community will be involved and schools from all over Europe will be invited to participate with the aim of bringing planetary science to a larger audience.

SciBox, an end-to-end automated science planning and commanding system

Science.gov (United States)

Choo, Teck H.; Murchie, Scott L.; Bedini, Peter D.; Steele, R. Josh; Skura, Joseph P.; Nguyen, Lillian; Nair, Hari; Lucks, Michael; Berman, Alice F.; McGovern, James A.; Turner, F. Scott

2014-01-01

SciBox is a new technology for planning and commanding science operations for Earth-orbital and planetary space missions. It has been incrementally developed since 2001 and demonstrated on several spaceflight projects. The technology has matured to the point that it is now being used to plan and command all orbital science operations for the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) mission to Mercury. SciBox encompasses the derivation of observing sequences from science objectives, the scheduling of those sequences, the generation of spacecraft and instrument commands, and the validation of those commands prior to uploading to the spacecraft. Although the process is automated, science and observing requirements are incorporated at each step by a series of rules and parameters to optimize observing opportunities, which are tested and validated through simulation and review. Except for limited special operations and tests, there is no manual scheduling of observations or construction of command sequences. SciBox reduces the lead time for operations planning by shortening the time-consuming coordination process, reduces cost by automating the labor-intensive processes of human-in-the-loop adjudication of observing priorities, reduces operations risk by systematically checking constraints, and maximizes science return by fully evaluating the trade space of observing opportunities to meet MESSENGER science priorities within spacecraft recorder, downlink, scheduling, and orbital-geometry constraints.

Preface: SciDAC 2009

Science.gov (United States)

Simon, Horst

2009-07-01

By almost any measure, the SciDAC community has come a long way since DOE launched the SciDAC program back in 2001. At the time, we were grappling with how to efficiently run applications on terascale systems (the November 2001 TOP500 list was led by DOE's ASCI White IBM system at Lawrence Livermore achieving 7.2 teraflop/s). And the results stemming from the first round of SciDAC projects were summed up in two-page reports. The scientific results were presented at annual meetings, which were by invitation only and typically were attended by about 75 researchers. Fast forward to 2009 and we now have SciDAC Review, a quarterly magazine showcasing the scientific computing contributions of SciDAC projects and related programs, all focused on presenting a comprehensive look at Scientific Discovery through Advanced Computing. That is also the motivation behind the annual SciDAC conference that in 2009 was held from June 14-18 in San Diego. The annual conference, which can also be described as a celebration of all things SciDAC, grew out those meetings organized in the early days of the program. In 2005, the meeting was held in San Francisco and attendance was opened up to all members of the SciDAC community. The schedule was also expanded to include a keynote address, plenary speakers and other features found in a conference format. This year marks the fifth such SciDAC conference, which now comprises four days of computational science presentations, multiple poster sessions and, since last year, an evening event showcasing simulations and modeling runs resulting from SciDAC projects. The fifth annual SciDAC conference was remarkable on several levels. The primary purpose, of course, is to showcase the research accomplishments resulting from SciDAC programs in particular and computational science in general. It is these accomplishments, represented in 38 papers and 52 posters, that comprise this set of conference proceedings. These proceedings can stand alone as

The Detection and Characterization of Extrasolar Planets

Directory of Open Access Journals (Sweden)

Ken Rice

2014-09-01

Full Text Available We have now confirmed the existence of > 1800 planets orbiting stars other thanthe Sun; known as extrasolar planets or exoplanets. The different methods for detectingsuch planets are sensitive to different regions of parameter space, and so, we are discoveringa wide diversity of exoplanets and exoplanetary systems. Characterizing such planets isdifficult, but we are starting to be able to determine something of their internal compositionand are beginning to be able to probe their atmospheres, the first step towards the detectionof bio-signatures and, hence, determining if a planet could be habitable or not. Here, Iwill review how we detect exoplanets, how we characterize exoplanetary systems and theexoplanets themselves, where we stand with respect to potentially habitable planets and howwe are progressing towards being able to actually determine if a planet could host life or not.

[Extrasolar terrestrial planets and possibility of extraterrestrial life].

Science.gov (United States)

Ida, Shigeru

2003-12-01

Recent development of research on extrasolar planets are reviewed. About 120 extrasolar Jupiter-mass planets have been discovered through the observation of Doppler shift in the light of their host stars that is caused by acceleration due to planet orbital motions. Although the extrasolar planets so far observed may be limited to gas giant planets and their orbits differ from those of giant planets in our Solar system (Jupiter and Saturn), the theoretically predicted probability of existence of extrasolar terrestrial planets that can have liquid water ocean on their surface is comparable to that of detectable gas giant planets. Based on the number of extrasolar gas giants detected so far, about 100 life-sustainable planets may exist within a range of 200 light years. Indirect observation of extrasolar terrestrial planets would be done with space telescopes within several years and direct one may be done within 20 years. The latter can detect biomarkers on these planets as well.

A septet of Earth-sized planets

Science.gov (United States)

Triaud, Amaury; SPECULOOS Team; TRAPPIST-1 Team

2017-10-01

Understanding the astronomical requirements for life to emerge, and to persist, on a planet is one of the most important and exciting scientific endeavours, yet without empirical answers. To resolve this, multiple planets whose sizes and surface temperatures are similar to the Earth, need to be discovered. Those planets also need to possess properties enabling detailed atmospheric characterisation with forthcoming facilities, from which chemical traces produced by biological activity can in principle be identified.I will describe a dedicated search for such planets called SPECULOOS. Our first detection is the TRAPPIST-1 system. Intensive ground-based and space-based observations have revealed that at least seven planets populate this system. We measured their radii and obtained first estimates of their masses thanks to transit-timing variations. I will describe our on-going observational efforts aiming to reduce our uncertainties on the planet properties. The incident flux on the planets ranges from Mercury to Ceres, comprising the Earth, and permitting climatic comparisons between each of those worlds such as is not possible within our Solar system. All seven planets have the potential to harbour liquid water on at least a fraction of their surfaces, given some atmospheric and geological conditions.

THE STEPPENWOLF: A PROPOSAL FOR A HABITABLE PLANET IN INTERSTELLAR SPACE

International Nuclear Information System (INIS)

Abbot, D. S.; Switzer, E. R.

2011-01-01

Rogue planets have been ejected from their planetary system. We investigate the possibility that a rogue planet could maintain a liquid ocean under layers of thermally insulating water ice and frozen gas as a result of geothermal heat flux. We find that a rogue planet of Earth-like composition and age could maintain a subglacial liquid ocean if it were ∼3.5 times more massive than Earth, corresponding to ∼8 km of ice. Suppression of the melting point by contaminants, a layer of frozen gas, or a larger complement of water could significantly reduce the planetary mass that is required to maintain a liquid ocean. Such a planet could be detected from reflected solar radiation, and its thermal emission could be characterized in the far-IR if it were to pass within O(1000) AU of Earth.

Extrasolar binary planets. I. Formation by tidal capture during planet-planet scattering

International Nuclear Information System (INIS)

Ochiai, H.; Nagasawa, M.; Ida, S.

2014-01-01

We have investigated (1) the formation of gravitationally bounded pairs of gas-giant planets (which we call 'binary planets') from capturing each other through planet-planet dynamical tide during their close encounters and (2) the subsequent long-term orbital evolution due to planet-planet and planet-star quasi-static tides. For the initial evolution in phase 1, we carried out N-body simulations of the systems consisting of three Jupiter-mass planets taking into account the dynamical tide. The formation rate of the binary planets is as much as 10% of the systems that undergo orbital crossing, and this fraction is almost independent of the initial stellarcentric semimajor axes of the planets, while ejection and merging rates sensitively depend on the semimajor axes. As a result of circularization by the planet-planet dynamical tide, typical binary separations are a few times the sum of the physical radii of the planets. After the orbital circularization, the evolution of the binary system is governed by long-term quasi-static tide. We analytically calculated the quasi-static tidal evolution in phase 2. The binary planets first enter the spin-orbit synchronous state by the planet-planet tide. The planet-star tide removes angular momentum of the binary motion, eventually resulting in a collision between the planets. However, we found that the binary planets survive the tidal decay for the main-sequence lifetime of solar-type stars (∼10 Gyr), if the binary planets are beyond ∼0.3 AU from the central stars. These results suggest that the binary planets can be detected by transit observations at ≳ 0.3 AU.

Basics of SCI Rehabilitation

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75 FR 24747 - SCI, LLC/Zener-Rectifier Operations Division A Wholly Owned Subsidiary of SCI, LLC/ON...

Science.gov (United States)

2010-05-05

... DEPARTMENT OF LABOR Employment and Training Administration [TA-W-70,235] SCI, LLC/Zener-Rectifier... Adjustment Assistance on October 19, 2009, applicable to workers of SCI LLC/Zener-Rectifier, Operations... Technical Resources were employed on-site at the Phoenix Arizona location of SCI LLC/Zener-Rectifier...

Orbital Dynamics of Exomoons During Planet–Planet Scattering

Science.gov (United States)

Hong, Yu-Cian; Lunine, Jonathan I.; Nicholson, Philip; Raymond, Sean N.

2018-04-01

Planet–planet scattering is the leading mechanism to explain the broad eccentricity distribution of observed giant exoplanets. Here we study the orbital stability of primordial giant planet moons in this scenario. We use N-body simulations including realistic oblateness and evolving spin evolution for the giant planets. We find that the vast majority (~80%–90% across all our simulations) of orbital parameter space for moons is destabilized. There is a strong radial dependence, as moons past are systematically removed. Closer-in moons on Galilean-moon-like orbits (system, be captured by another planet, be ejected but still orbiting its free-floating host planet, or survive on heliocentric orbits as "planets." The survival rate of moons increases with the host planet mass but is independent of the planet's final (post-scattering) orbits. Based on our simulations, we predict the existence of an abundant galactic population of free-floating (former) moons.

SCI based data acquisition architectures

International Nuclear Information System (INIS)

Bogaerts, J.A.C.; Divia, R.; Renardy, J.F.

1992-01-01

This paper discusses the Scalable Coherent Interface (SCI), an IEEE proposed standard (P1596) for interconnecting multiprocessor systems. The standard defines point to point connections between nodes, which can be processors, memories or I/O devices. Networks containing a maximum of 64K nodes with a bandwidth of one Gbyte/s between nodes, may be constructed. SCI is an attractive candidate to serve as a backbone for high speed, large volume data acquisition systems such as required by future experiments at the proposed Large Hadron Collider (LHC) at CERN. Work has started to simulate SCI based architectures for data acquisition systems. The simulation program proved to be a useful tool to study SCI systems. First results are reported on a model of a large LHC experiment containing over 1000 nodes

Terrestrial Planet Finder Coronagraph High Accuracy Optical Propagation, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — The Terrestrial Planet Finder (TPF) project is considering several approaches to discovering planets orbiting stars far from earth and assessing their suitability to...

Earth observations during Space Shuttle mission STS-45 Mission to Planet Earth - March 24-April 2, 1992

Science.gov (United States)

Pitts, David E.; Helfert, Michael R.; Lulla, Kamlesh P.; Mckay, Mary F.; Whitehead, Victor S.; Amsbury, David L.; Bremer, Jeffrey; Ackleson, Steven G.; Evans, Cynthia A.; Wilkinson, M. J.

1992-01-01

A description is presented of the activities and results of the Space Shuttle mission STS-45, known as the Mission to Planet Earth. Observations of Mount St. Helens, Manila Bay and Mt. Pinatubo, the Great Salt Lake, the Aral Sea, and the Siberian cities of Troitsk and Kuybyshev are examined. The geological features and effects of human activity seen in photographs of these areas are pointed out.

The HARPS-N Rocky Planet Search

DEFF Research Database (Denmark)

Motalebi, F.; Udry, S.; Gillon, M.

2015-01-01

We know now from radial velocity surveys and transit space missions that planets only a few times more massive than our Earth are frequent around solar-type stars. Fundamental questions about their formation history, physical properties, internal structure, and atmosphere composition are, however......, still to be solved. We present here the detection of a system of four low-mass planets around the bright (V = 5.5) and close-by (6.5 pc) star HD 219134. This is the first result of the Rocky Planet Search programme with HARPS-N on the Telescopio Nazionale Galileo in La Palma. The inner planet orbits...... on a close-in, quasi-circular orbit with a period of 6.767 ± 0.004 days. The third planet in the system has a period of 46.66 ± 0.08 days and a minimum-mass of 8.94 ± 1.13 M⊕, at 0.233 ± 0.002 AU from the star. Its eccentricity is 0.46 ± 0.11. The period of this planet is close to the rotational period...

TWO SMALL PLANETS TRANSITING HD 3167

International Nuclear Information System (INIS)

Vanderburg, Andrew; Bieryla, Allyson; Latham, David W.; Mayo, Andrew W.; Berlind, Perry; Duev, Dmitry A.; Jensen-Clem, Rebecca; Kulkarni, Shrinivas; Riddle, Reed; Baranec, Christoph; Law, Nicholas M.; Nieberding, Megan N.; Salama, Maïssa

2016-01-01

We report the discovery of two super-Earth-sized planets transiting the bright (V = 8.94, K = 7.07) nearby late G-dwarf HD 3167, using data collected by the K2 mission. The inner planet, HD 3167 b, has a radius of 1.6 R ⊕ and an ultra-short orbital period of only 0.96 days. The outer planet, HD 3167 c, has a radius of 2.9 R ⊕ and orbits its host star every 29.85 days. At a distance of just 45.8 ± 2.2 pc, HD 3167 is one of the closest and brightest stars hosting multiple transiting planets, making HD 3167 b and c well suited for follow-up observations. The star is chromospherically inactive with low rotational line-broadening, ideal for radial velocity observations to measure the planets’ masses. The outer planet is large enough that it likely has a thick gaseous envelope that could be studied via transmission spectroscopy. Planets transiting bright, nearby stars like HD 3167 are valuable objects to study leading up to the launch of the James Webb Space Telescope .

PLANET-PLANET SCATTERING IN PLANETESIMAL DISKS

International Nuclear Information System (INIS)

Raymond, Sean N.; Armitage, Philip J.; Gorelick, Noel

2009-01-01

We study the final architecture of planetary systems that evolve under the combined effects of planet-planet and planetesimal scattering. Using N-body simulations we investigate the dynamics of marginally unstable systems of gas and ice giants both in isolation and when the planets form interior to a planetesimal belt. The unstable isolated systems evolve under planet-planet scattering to yield an eccentricity distribution that matches that observed for extrasolar planets. When planetesimals are included the outcome depends upon the total mass of the planets. For M tot ∼> 1 M J the final eccentricity distribution remains broad, whereas for M tot ∼ J a combination of divergent orbital evolution and recircularization of scattered planets results in a preponderance of nearly circular final orbits. We also study the fate of marginally stable multiple planet systems in the presence of planetesimal disks, and find that for high planet masses the majority of such systems evolve into resonance. A significant fraction leads to resonant chains that are planetary analogs of Jupiter's Galilean satellites. We predict that a transition from eccentric to near-circular orbits will be observed once extrasolar planet surveys detect sub-Jovian mass planets at orbital radii of a ≅ 5-10 AU.

Sex and Fertility After SCI

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Sex and Fertility After SCI

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Sex and Fertility After SCI

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Sex and Fertility After SCI

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Sex and Fertility After SCI

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Sex and Fertility After SCI

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Sex and Fertility After SCI

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SCI Hazard Report Methodology

Science.gov (United States)

Mitchell, Michael S.

2010-01-01

This slide presentation reviews the methodology in creating a Source Control Item (SCI) Hazard Report (HR). The SCI HR provides a system safety risk assessment for the following Ares I Upper Stage Production Contract (USPC) components (1) Pyro Separation Systems (2) Main Propulsion System (3) Reaction and Roll Control Systems (4) Thrust Vector Control System and (5) Ullage Settling Motor System components.

Phase density of neutrons emitted by an atmosphereless planet

International Nuclear Information System (INIS)

Goryachev, B.I.; Isakov, A.I.; Lin'kova, N.V.

1986-01-01

An approach to calculation of small planet neutron emission characteristics is developed. Using artificial satellites and space probes information on the planet surface may be obtained by analyzing neutron emission being the result of cosmic rays effect. Available calculation methods permit to calculate angular distribution and neutron flux F 0 from planet surface as a function of its surface layer chemical composition. Neutron flux measured by a sattelite and F 0 flux may be connected by a function describing neuton phase density near the planet

SciSpark's SRDD : A Scientific Resilient Distributed Dataset for Multidimensional Data

Science.gov (United States)

Palamuttam, R. S.; Wilson, B. D.; Mogrovejo, R. M.; Whitehall, K. D.; Mattmann, C. A.; McGibbney, L. J.; Ramirez, P.

2015-12-01

Remote sensing data and climate model output are multi-dimensional arrays of massive sizes locked away in heterogeneous file formats (HDF5/4, NetCDF 3/4) and metadata models (HDF-EOS, CF) making it difficult to perform multi-stage, iterative science processing since each stage requires writing and reading data to and from disk. We have developed SciSpark, a robust Big Data framework, that extends ApacheTM Spark for scaling scientific computations. Apache Spark improves the map-reduce implementation in ApacheTM Hadoop for parallel computing on a cluster, by emphasizing in-memory computation, "spilling" to disk only as needed, and relying on lazy evaluation. Central to Spark is the Resilient Distributed Dataset (RDD), an in-memory distributed data structure that extends the functional paradigm provided by the Scala programming language. However, RDDs are ideal for tabular or unstructured data, and not for highly dimensional data. The SciSpark project introduces the Scientific Resilient Distributed Dataset (sRDD), a distributed-computing array structure which supports iterative scientific algorithms for multidimensional data. SciSpark processes data stored in NetCDF and HDF files by partitioning them across time or space and distributing the partitions among a cluster of compute nodes. We show usability and extensibility of SciSpark by implementing distributed algorithms for geospatial operations on large collections of multi-dimensional grids. In particular we address the problem of scaling an automated method for finding Mesoscale Convective Complexes. SciSpark provides a tensor interface to support the pluggability of different matrix libraries. We evaluate performance of the various matrix libraries in distributed pipelines, such as Nd4jTM and BreezeTM. We detail the architecture and design of SciSpark, our efforts to integrate climate science algorithms, parallel ingest and partitioning (sharding) of A-Train satellite observations from model grids. These

Preface: SciDAC 2006

Science.gov (United States)

Tang, William M., Dr.

2006-01-01

The second annual Scientific Discovery through Advanced Computing (SciDAC) Conference was held from June 25-29, 2006 at the new Hyatt Regency Hotel in Denver, Colorado. This conference showcased outstanding SciDAC-sponsored computational science results achieved during the past year across many scientific domains, with an emphasis on science at scale. Exciting computational science that has been accomplished outside of the SciDAC program both nationally and internationally was also featured to help foster communication between SciDAC computational scientists and those funded by other agencies. This was illustrated by many compelling examples of how domain scientists collaborated productively with applied mathematicians and computer scientists to effectively take advantage of terascale computers (capable of performing trillions of calculations per second) not only to accelerate progress in scientific discovery in a variety of fields but also to show great promise for being able to utilize the exciting petascale capabilities in the near future. The SciDAC program was originally conceived as an interdisciplinary computational science program based on the guiding principle that strong collaborative alliances between domain scientists, applied mathematicians, and computer scientists are vital to accelerated progress and associated discovery on the world's most challenging scientific problems. Associated verification and validation are essential in this successful program, which was funded by the US Department of Energy Office of Science (DOE OS) five years ago. As is made clear in many of the papers in these proceedings, SciDAC has fundamentally changed the way that computational science is now carried out in response to the exciting challenge of making the best use of the rapid progress in the emergence of more and more powerful computational platforms. In this regard, Dr. Raymond Orbach, Energy Undersecretary for Science at the DOE and Director of the OS has stated

Leveraging the Thousands of Known Planets to Inform TESS Follow-Up

Science.gov (United States)

Ballard, Sarah

2017-10-01

The Solar System furnishes our most familiar planetary architecture: many planets, orbiting nearly coplanar to one another. However, a typical system of planets in the Milky Way orbits a much smaller M dwarf star, and these stars furnish a different blueprint in key ways than the conditions that nourished evolution of life on Earth. With ensemble studies of hundreds-to-thousands of exoplanets, I will describe the emerging links between planet formation from disks, orbital dynamics of planets, and the content and observability of planetary atmospheres. These quantities can be tied to observables even in discovery light curves, to enable judicious selection of follow-up targets from the ground and from space. After TESS exoplanet discoveries start in earnest, the studies of individual planets with large, space-based platforms comprise the clear next step toward understanding the hospitability of the Milky Way to life. Our success hinges upon leveraging the many thousands of planet discoveries in hand to determine how to use these precious and limited resources.

Combined SCI and TBI: recovery of forelimb function after unilateral cervical spinal cord injury (SCI) is retarded by contralateral traumatic brain injury (TBI), and ipsilateral TBI balances the effects of SCI on paw placement.

Science.gov (United States)

Inoue, Tomoo; Lin, Amity; Ma, Xiaokui; McKenna, Stephen L; Creasey, Graham H; Manley, Geoffrey T; Ferguson, Adam R; Bresnahan, Jacqueline C; Beattie, Michael S

2013-10-01

A significant proportion (estimates range from 16 to 74%) of patients with spinal cord injury (SCI) have concomitant traumatic brain injury (TBI), and the combination often produces difficulties in planning and implementing rehabilitation strategies and drug therapies. For example, many of the drugs used to treat SCI may interfere with cognitive rehabilitation, and conversely drugs that are used to control seizures in TBI patients may undermine locomotor recovery after SCI. The current paper presents an experimental animal model for combined SCI and TBI to help drive mechanistic studies of dual diagnosis. Rats received a unilateral SCI (75 kdyn) at C5 vertebral level, a unilateral TBI (2.0 mm depth, 4.0 m/s velocity impact on the forelimb sensori-motor cortex), or both SCI+TBI. TBI was placed either contralateral or ipsilateral to the SCI. Behavioral recovery was examined using paw placement in a cylinder, grooming, open field locomotion, and the IBB cereal eating test. Over 6weeks, in the paw placement test, SCI+contralateral TBI produced a profound deficit that failed to recover, but SCI+ipsilateral TBI increased the relative use of the paw on the SCI side. In the grooming test, SCI+contralateral TBI produced worse recovery than either lesion alone even though contralateral TBI alone produced no observable deficit. In the IBB forelimb test, SCI+contralateral TBI revealed a severe deficit that recovered in 3 weeks. For open field locomotion, SCI alone or in combination with TBI resulted in an initial deficit that recovered in 2 weeks. Thus, TBI and SCI affected forelimb function differently depending upon the test, reflecting different neural substrates underlying, for example, exploratory paw placement and stereotyped grooming. Concurrent SCI and TBI had significantly different effects on outcomes and recovery, depending upon laterality of the two lesions. Recovery of function after cervical SCI was retarded by the addition of a moderate TBI in the contralateral

The Problem of Extraterrestrial Civilizations and Extrasolar Planets

Science.gov (United States)

Mickaelian, A. M.

2015-07-01

The problem of extraterrestrial intelligence is the best example of multidisciplinary science. Here philosophy and religion, astronomy, radiophysics, spectrography, space flights and astronautics, geology and planetology, astroecology, chemistry and biology, history and archaeology, psychology, sociology, linguistics, diplomacy, UFOs and peculiar phenomena are involved. Among these many-sided studies, astronomers have probably displayed the most progress by discovering thousands of extrasolar planets. At present, a number of search programs are being accomplished, including those with space telescopes, and planets in so-called "habitable zone" are considered as most important ones, for which various orbital and physical parameters are being calculated. As the discovery of extraterrestrial life is the final goal, a special attention is given to Earth-like planets, for the discovery of which most sensitive technical means are necessary.

TWO SMALL PLANETS TRANSITING HD 3167

Energy Technology Data Exchange (ETDEWEB)

Vanderburg, Andrew; Bieryla, Allyson; Latham, David W.; Mayo, Andrew W.; Berlind, Perry [Harvard–Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Duev, Dmitry A.; Jensen-Clem, Rebecca; Kulkarni, Shrinivas; Riddle, Reed [California Institute of Technology, Pasadena, CA 91125 (United States); Baranec, Christoph [University of Hawai‘i at Mānoa, Hilo, HI 96720 (United States); Law, Nicholas M. [University of North Carolina at Chapel Hill, Chapel Hill, NC 27599 (United States); Nieberding, Megan N. [National Optical Astronomy Observatory, 950 N. Cherry Avenue, Tucson, AZ 85719 (United States); Salama, Maïssa, E-mail: avanderburg@cfa.harvard.edu [University of Hawai‘i at Mānoa, Honolulu, HI 96822 (United States)

2016-09-20

We report the discovery of two super-Earth-sized planets transiting the bright (V = 8.94, K = 7.07) nearby late G-dwarf HD 3167, using data collected by the K2 mission. The inner planet, HD 3167 b, has a radius of 1.6 R {sub ⊕} and an ultra-short orbital period of only 0.96 days. The outer planet, HD 3167 c, has a radius of 2.9 R {sub ⊕} and orbits its host star every 29.85 days. At a distance of just 45.8 ± 2.2 pc, HD 3167 is one of the closest and brightest stars hosting multiple transiting planets, making HD 3167 b and c well suited for follow-up observations. The star is chromospherically inactive with low rotational line-broadening, ideal for radial velocity observations to measure the planets’ masses. The outer planet is large enough that it likely has a thick gaseous envelope that could be studied via transmission spectroscopy. Planets transiting bright, nearby stars like HD 3167 are valuable objects to study leading up to the launch of the James Webb Space Telescope .

The DARWIN mission: Search for extra-solar planets

Science.gov (United States)

Kaltenegger, L.; Fridlund, M.

The direct detection of a planet close to its parent star is challenging because the signal detected from the parent star is between 109 and 106 times brighter than the signal of a planet in the visual and IR respectively. Future space based missions like DARWIN and TPF concentrate on the region between 6μ m to 18μ m, a region that contains the CO2, H2O, O3 spectral features of the atmosphere. The presence or absence of these spectral features would indicate similarities or differences with the atmosphere of telluric planets. The Infra Red Space Interferometer DARWIN is an integral part of ESA's Cosmic Vision 2020 plan, intended for a launch towards the middle of next decade. It is constructed around the new technique of `nulling interferometry', which exploits the wave nature of light to extinguish light from an on-axis bright object (the central star in this case), while at the same time light from a nearby source (the planet) is enhanced. An overview and update of the science of the DARWIN mission is given.

Planet Press: an EGU initiative to bring geoscientific research to children

Science.gov (United States)

Ferreira, Bárbara

2016-04-01

Planet Press (http://www.egu.eu/education/planet-press/) is an EGU educational project that aims to get children (mainly 7-13 year olds), as well as their parents and educators, interested in and engaged with up-to-date scientific research and news. Planet Press articles are short versions of EGU press releases written in child-friendly language. Because EGU press releases cover research published in the various EGU scientific journals, Planet Press focuses on topics as varied as air pollution, glaciers, climate change, earthquakes, ocean sciences, droughts and floods, or space sciences. The texts are reviewed by both scientists and educators to make sure they are accurate and clear to their target audience. By sharing new and exciting geoscientific research with young kids, we hope to inspire them to develop an interest in the Earth, planetary and space sciences. In this presentation, we describe how the Planet Press idea came about, how the project is run, and the challenges and lessons learnt since the launch of this educational initiative in 2014. Planet Press, which has the support of the EGU Committee on Education, is made possible by the work of volunteer scientists and educators who review and translate the texts. We are grateful for the help of Jane Robb, former EGU Educational Fellow, with launching the project. Planet Press is inspired by Space Scoop (http://www.spacescoop.org/), an initiative by UNAWE, the EU-Universe Awareness organisation, that brings astronomy news to children every week.

An electrodynamic model of the solar wind interaction with the ionospheres of Mars and Venus

International Nuclear Information System (INIS)

Cloutier, P.A.; Daniell, R.E. Jr.

1979-01-01

the electrodynamic model for the solar wind interaction with non-magnetic planets (Cloutier and Daniell, Planet. Space Sci. 21, 463, 1973; Daniell and Cloutier, Planet. Space Sci. 25, 621, 1977) is modified to include the effects of non-ohmic currents in the upper ionosphere. The model is then used to calculate convection patterns induced by the solar wind in the ionospheres of Mars and Venus. For Mars the observations of the neutral mass spectrometer or Vikings 1 and 2 provided the neutral atmosphere. Model calculations reproduced the retarding potential analyzer data and indicate that the ionosphere above about 200 km is probably controlled by convection rather than chemistry or diffusion. For Venus a model atmosphere based on Dickenson and Ridley, J. Atmos. Sci. 32, 1219 (1975) and Mayr et al., J. Geophys. Res. 83, 4411 (1978) was used. The resulting model calculations were compared to radio occultation data from Mariners 5 and 10 and Venera 9 which represent extremes in the variability of the upper Cytherean ionosphere. The model calculations are shown to fall within this variation. These results represent the state of the theory immediately prior to the Pioneer-Venus encounter. (author)

Characterizing the Evolution of Circumstellar Systems with the Hubble Space Telescope and the Gemini Planet Imager

Science.gov (United States)

Wolff, Schuyler; Schuyler G. Wolff

2018-01-01

The study of circumstellar disks at a variety of evolutionary stages is essential to understand the physical processes leading to planet formation. The recent development of high contrast instruments designed to directly image the structures surrounding nearby stars, such as the Gemini Planet Imager (GPI) and coronagraphic data from the Hubble Space Telescope (HST) have made detailed studies of circumstellar systems possible. In my thesis work I detail the observation and characterization of three systems. GPI polarization data for the transition disk, PDS 66 shows a double ring and gap structure with a temporally variable azimuthal asymmetry. This evolved morphology could indicate shadowing from some feature in the innermost regions of the disk, a gap-clearing planet, or a localized change in the dust properties of the disk. Millimeter continuum data of the DH Tau system places limits on the dust mass that is contributing to the strong accretion signature on the wide-separation planetary mass companion, DH Tau b. The lower than expected dust mass constrains the possible formation mechanism, with core accretion followed by dynamical scattering being the most likely. Finally, I present HST scattered light observations of the flared, edge-on protoplanetary disk ESO H$\\alpha$ 569. I combine these data with a spectral energy distribution to model the key structural parameters such as the geometry (disk outer radius, vertical scale height, radial flaring profile), total mass, and dust grain properties in the disk using the radiative transfer code MCFOST. In order to conduct this work, I developed a new tool set to optimize the fitting of disk parameters using the MCMC code \\texttt{emcee} to efficiently explore the high dimensional parameter space. This approach allows us to self-consistently and simultaneously fit a wide variety of observables in order to place constraints on the physical properties of a given disk, while also rigorously assessing the uncertainties in

Identifying Exoplanets with Deep Learning: A Five-planet Resonant Chain around Kepler-80 and an Eighth Planet around Kepler-90

Science.gov (United States)

Shallue, Christopher J.; Vanderburg, Andrew

2018-02-01

NASA’s Kepler Space Telescope was designed to determine the frequency of Earth-sized planets orbiting Sun-like stars, but these planets are on the very edge of the mission’s detection sensitivity. Accurately determining the occurrence rate of these planets will require automatically and accurately assessing the likelihood that individual candidates are indeed planets, even at low signal-to-noise ratios. We present a method for classifying potential planet signals using deep learning, a class of machine learning algorithms that have recently become state-of-the-art in a wide variety of tasks. We train a deep convolutional neural network to predict whether a given signal is a transiting exoplanet or a false positive caused by astrophysical or instrumental phenomena. Our model is highly effective at ranking individual candidates by the likelihood that they are indeed planets: 98.8% of the time it ranks plausible planet signals higher than false-positive signals in our test set. We apply our model to a new set of candidate signals that we identified in a search of known Kepler multi-planet systems. We statistically validate two new planets that are identified with high confidence by our model. One of these planets is part of a five-planet resonant chain around Kepler-80, with an orbital period closely matching the prediction by three-body Laplace relations. The other planet orbits Kepler-90, a star that was previously known to host seven transiting planets. Our discovery of an eighth planet brings Kepler-90 into a tie with our Sun as the star known to host the most planets.

SciServer: An Online Collaborative Environment for Big Data in Research and Education

Science.gov (United States)

Raddick, Jordan; Souter, Barbara; Lemson, Gerard; Taghizadeh-Popp, Manuchehr

2017-01-01

For the past year, SciServer Compute (http://compute.sciserver.org) has offered access to big data resources running within server-side Docker containers. Compute has allowed thousands of researchers to bring advanced analysis to big datasets like the Sloan Digital Sky Survey and others, while keeping the analysis close to the data for better performance and easier read/write access. SciServer Compute is just one part of the SciServer system being developed at Johns Hopkins University, which provides an easy-to-use collaborative research environment for astronomy and many other sciences.SciServer enables these collaborative research strategies using Jupyter notebooks, in which users can write their own Python and R scripts and execute them on the same server as the data. We have written special-purpose libraries for querying, reading, and writing data. Intermediate results can be stored in large scratch space (hundreds of TBs) and analyzed directly from within Python or R with state-of-the-art visualization and machine learning libraries. Users can store science-ready results in their permanent allocation on SciDrive, a Dropbox-like system for sharing and publishing files.SciServer Compute’s virtual research environment has grown with the addition of task management and access control functions, allowing collaborators to share both data and analysis scripts securely across the world. These features also open up new possibilities for education, allowing instructors to share datasets with students and students to write analysis scripts to share with their instructors. We are leveraging these features into a new system called “SciServer Courseware,” which will allow instructors to share assignments with their students, allowing students to engage with big data in new ways.SciServer has also expanded to include more datasets beyond the Sloan Digital Sky Survey. A part of that growth has been the addition of the SkyQuery component, which allows for simple, fast

First Light from Extrasolar Planets and Implications for Astrobiology

Science.gov (United States)

Richardson, L. Jeremy; Seager, Sara; Harrington, Joseph; Deming, Drake

2005-01-01

The first light from an extrasolar planet was recently detected. These results, obtained for two transiting extrasolar planets at different infrared wavelengths, open a new era in the field of extrasolar planet detection and characterization because for the first time we can now detect planets beyond the solar system directly. Using the Spitzer Space Telescope at 24 microns, we observed the modulation of combined light (star plus planet) from the HD 209458 system as the planet disappeared behind the star during secondary eclipse and later re-emerged, thereby isolating the light from the planet. We obtained a planet-to-star ratio of 0.26% at 24 microns, corresponding to a brightness temperature of 1130 + / - 150 K. We will describe this result in detail, explain what it can tell us about the atmosphere of HD 209458 b, and discuss implications for the field of astrobiology. These results represent a significant step on the path to detecting terrestrial planets around other stars and in understanding their atmospheres in terms of composition and temperature.

T-1025 IU SciBath-768 detector tests in MI-12

International Nuclear Information System (INIS)

Tayloe, Rex; Cooper, R.; Garrison, L.; Thornton, T.; Rebenitsch, L.; DeJongh, Fritz; Loer, Benjamin; Ramberg, Erik; Yoo, Jonghee

2012-01-01

This is a memorandum of understanding between the Fermi National Accelerator Laboratory (Fermilab) and the experimenters of Department of Physics and Center for Exploration of Energy and Matter, Indiana University, who have committed to participate in detector tests to be carried out during the 2012 Fermilab Neutrino program. The memorandum is intended solely for the purpose of recording expectations for budget estimates and work allocations for Fermilab, the funding agencies and the participating institutions. it reflects an arrangement that currently is satisfactory to the parties; however, it is recognized and anticipated that changing circumstances of the evolving research program will necessitate revisions. The parties agree to modify this memorandum to reflect such required adjustments. Actual contractual obligations will be set forth in separate documents. The experimenters propsoe to test their prototype 'SciBat-768' detector in the MI-12 building for 3 months (February-April) in Spring 2012. The major goal of this effort is to measure or limit the flux of beam-induced neutrons in a far-off-axis (> 45 o ) location of the Booster Neutrino Beamline (BNB). This flux is of interest for a proposed coherent neutral-current neutrino-argon elastic scattering experiment. A second goal is to collect more test data for the SciBath-768 to enable better understanding and calibration of the device. The SciBath-768 detector successfully ran for 3 months in the MINOS Underground Area in Fall 2011 as testbeam experiment T-1014 and is currently running above ground in the MINOS service building. For the run proposed here, the experiments are requesting: space in MI-12 in which to run the SciBath detector during February-April 2012 while the BNB is operating; technical support to help with moving the equipment on site; access to power, internet, and accelerator signals; and a small office space from which to run and monitor the experiment.

T-1025 IU SciBath-768 detector tests in MI-12

Energy Technology Data Exchange (ETDEWEB)

Tayloe, Rex; Cooper, R.; Garrison, L.; Thornton, T.; Rebenitsch, L.; /Indiana U.; DeJongh, Fritz; Loer, Benjamin; Ramberg, Erik; Yoo, Jonghee; /Fermilab

2012-02-11

This is a memorandum of understanding between the Fermi National Accelerator Laboratory (Fermilab) and the experimenters of Department of Physics and Center for Exploration of Energy and Matter, Indiana University, who have committed to participate in detector tests to be carried out during the 2012 Fermilab Neutrino program. The memorandum is intended solely for the purpose of recording expectations for budget estimates and work allocations for Fermilab, the funding agencies and the participating institutions. it reflects an arrangement that currently is satisfactory to the parties; however, it is recognized and anticipated that changing circumstances of the evolving research program will necessitate revisions. The parties agree to modify this memorandum to reflect such required adjustments. Actual contractual obligations will be set forth in separate documents. The experimenters propsoe to test their prototype 'SciBat-768' detector in the MI-12 building for 3 months (February-April) in Spring 2012. The major goal of this effort is to measure or limit the flux of beam-induced neutrons in a far-off-axis (> 45{sup o}) location of the Booster Neutrino Beamline (BNB). This flux is of interest for a proposed coherent neutral-current neutrino-argon elastic scattering experiment. A second goal is to collect more test data for the SciBath-768 to enable better understanding and calibration of the device. The SciBath-768 detector successfully ran for 3 months in the MINOS Underground Area in Fall 2011 as testbeam experiment T-1014 and is currently running above ground in the MINOS service building. For the run proposed here, the experiments are requesting: space in MI-12 in which to run the SciBath detector during February-April 2012 while the BNB is operating; technical support to help with moving the equipment on site; access to power, internet, and accelerator signals; and a small office space from which to run and monitor the experiment.

Life in other planets

Energy Technology Data Exchange (ETDEWEB)

Ghosh, S N [Calcutta Univ. (India). Dept. of Applied Physics

1977-12-01

Speculations of life on other planets in space are discussed. The life history of a star in terms of the high-temperature fusion reactions taking place in it is outlined. The phenomenon of gases escaping from planetary atmospheres which destroys life on them is explained. Solar radiation effects, pulsar detection, etc., are briefly touched upon.

Prevalence of Earth-size planets orbiting Sun-like stars.

Science.gov (United States)

Petigura, Erik A; Howard, Andrew W; Marcy, Geoffrey W

2013-11-26

Determining whether Earth-like planets are common or rare looms as a touchstone in the question of life in the universe. We searched for Earth-size planets that cross in front of their host stars by examining the brightness measurements of 42,000 stars from National Aeronautics and Space Administration's Kepler mission. We found 603 planets, including 10 that are Earth size ( ) and receive comparable levels of stellar energy to that of Earth (1 - 2 R[Symbol: see text] ). We account for Kepler's imperfect detectability of such planets by injecting synthetic planet-caused dimmings into the Kepler brightness measurements and recording the fraction detected. We find that 11 ± 4% of Sun-like stars harbor an Earth-size planet receiving between one and four times the stellar intensity as Earth. We also find that the occurrence of Earth-size planets is constant with increasing orbital period (P), within equal intervals of logP up to ~200 d. Extrapolating, one finds 5.7(-2.2)(+1.7)% of Sun-like stars harbor an Earth-size planet with orbital periods of 200-400 d.

#AltPlanets: Exploring the Exoplanet Catalogue with Neural Networks

Science.gov (United States)

Laneuville, M.; Tasker, E. J.; Guttenberg, N.

2017-12-01

The launch of Kepler in 2009 brought the number of known exoplanets into the thousands, in a growth explosion that shows no sign of abating. While the data available for individual planets is presently typically restricted to orbital and bulk properties, the quantity of data points allows the potential for meaningful statistical analysis. It is not clear how planet mass, radius, orbital path, stellar properties and neighbouring planets influence one another, therefore it seems inevitable that patterns will be missed simply due to the difficulty of including so many dimensions. Even simple trends may be overlooked if they fall outside our expectation of planet formation; a strong risk in a field where new discoveries have destroyed theories from the first observations of hot Jupiters. A possible way forward is to take advantage of the capabilities of neural network autoencoders. The idea of such algorithms is to learn a representation (encoding) of the data in a lower dimension space, without a priori knowledge about links between the elements. This encoding space can then be used to discover the strongest correlations in the original dataset.The key point is that trends identified by a neural network are independent of any previous analysis and pre-conceived ideas about physical processes. Results can reveal new relationships between planet properties and verify existing trends. We applied this concept to study data from the NASA Exoplanet Archive and while we have begun to explore the potential use of neural networks for exoplanet data, there are many possible extensions. For example, the network can produce a large number of 'alternative planets' whose statistics should match the current distribution. This larger dataset could highlight gaps in the parameter space or indicate observations are missing particular regimes. This could guide instrument proposals towards objects liable to yield the most information.

Life in other planets

International Nuclear Information System (INIS)

Ghosh, S.N.

1977-01-01

Speculations of life on other planets in space are discussed. The life history of a star in terms of the high temperature fusion reactions taking place in it, is outlined. The phenomenon of gases escaping from planetary atmospheres which destroys life on them is explained. Solar radiation effects, pulsar detection etc. are briefly touched upon. (K.B.)

Prevalence of Earth-size planets orbiting Sun-like stars

OpenAIRE

Petigura, Erik A.; Howard, Andrew W.; Marcy, Geoffrey W.

2013-01-01

Determining whether Earth-like planets are common or rare looms as a touchstone in the question of life in the universe. We searched for Earth-size planets that cross in front of their host stars by examining the brightness measurements of 42,000 stars from National Aeronautics and Space Administration's Kepler mission. We found 603 planets, including 10 that are Earth size (1-2 Earth-radii) and receive comparable levels of stellar energy to that of Earth (within a factor of four). We account...

Kepler-36: a pair of planets with neighboring orbits and dissimilar densities.

Science.gov (United States)

Carter, Joshua A; Agol, Eric; Chaplin, William J; Basu, Sarbani; Bedding, Timothy R; Buchhave, Lars A; Christensen-Dalsgaard, Jørgen; Deck, Katherine M; Elsworth, Yvonne; Fabrycky, Daniel C; Ford, Eric B; Fortney, Jonathan J; Hale, Steven J; Handberg, Rasmus; Hekker, Saskia; Holman, Matthew J; Huber, Daniel; Karoff, Christopher; Kawaler, Steven D; Kjeldsen, Hans; Lissauer, Jack J; Lopez, Eric D; Lund, Mikkel N; Lundkvist, Mia; Metcalfe, Travis S; Miglio, Andrea; Rogers, Leslie A; Stello, Dennis; Borucki, William J; Bryson, Steve; Christiansen, Jessie L; Cochran, William D; Geary, John C; Gilliland, Ronald L; Haas, Michael R; Hall, Jennifer; Howard, Andrew W; Jenkins, Jon M; Klaus, Todd; Koch, David G; Latham, David W; MacQueen, Phillip J; Sasselov, Dimitar; Steffen, Jason H; Twicken, Joseph D; Winn, Joshua N

2012-08-03

In the solar system, the planets' compositions vary with orbital distance, with rocky planets in close orbits and lower-density gas giants in wider orbits. The detection of close-in giant planets around other stars was the first clue that this pattern is not universal and that planets' orbits can change substantially after their formation. Here, we report another violation of the orbit-composition pattern: two planets orbiting the same star with orbital distances differing by only 10% and densities differing by a factor of 8. One planet is likely a rocky "super-Earth," whereas the other is more akin to Neptune. These planets are 20 times more closely spaced and have a larger density contrast than any adjacent pair of planets in the solar system.

A probabilistic approach towards understanding how planet composition affects plate tectonics - through time and space.

Science.gov (United States)

Stamenkovic, V.

2017-12-01

We focus on the connections between plate tectonics and planet composition — by studying how plate yielding is affected by surface and mantle water, and by variable amounts of Fe, SiC, or radiogenic heat sources within the planet interior. We especially explore whether we can make any robust conclusions if we account for variable initial conditions, current uncertainties in model parameters and the pressure dependence of the viscosity, as well as uncertainties on how a variable composition affects mantle rheology, melting temperatures, and thermal conductivities. We use a 1D thermal evolution model to explore with more than 200,000 simulations the robustness of our results and use our previous results from 3D calculations to help determine the most likely scenario within the uncertainties we still face today. The results that are robust in spite of all uncertainties are that iron-rich mantle rock seems to reduce the efficiency of plate yielding occurring on silicate planets like the Earth if those planets formed along or above mantle solidus and that carbon planets do not seem to be ideal candidates for plate tectonics because of slower creep rates and generally higher thermal conductivities for SiC. All other conclusions depend on not yet sufficiently constrained parameters. For the most likely case based on our current understanding, we find that, within our range of varied planet conditions (1-10 Earth masses), planets with the greatest efficiency of plate yielding are silicate rocky planets of 1 Earth mass with large metallic cores (average density 5500-7000 kg m-3) with minimal mantle concentrations of iron (as little as 0% is preferred) and radiogenic isotopes at formation (up to 10 times less than Earth's initial abundance; less heat sources do not mean no heat sources). Based on current planet formation scenarios and observations of stellar abundances across the Galaxy as well as models of the evolution of the interstellar medium, such planets are

SCI-NutriNord - a Nordic Initiative on Patient Education on Nutrition for People with Spinal Cord Injury (SCI)

DEFF Research Database (Denmark)

Steensgaard, Randi

2017-01-01

People with SCI are at high risk of developing secondary conditions of which several are linked to nutrition: overweight/obesity, chronic constipation and/or diarrhea and pressure sores are some examples. Proper nutrition is imperative to prevent and treat these conditions. However, there is a lack...... of evidence-based information materials about healthy eating for people with SCI at least in the Nordic languages. The aim of this multidisciplinary workshop is to: A. Inform about SCI-NutriNord and the first steps that have been taken in developing materials on nutrition as educational teaching aids...... to malnutrition Target group for this workshop is persons who have an interest in problem areas linked to nutrition and SCI, and who want to take part in the development of relevant patient education materials....

Venus and Mercury as Planets

Science.gov (United States)

1974-01-01

A general evolutionary history of the solar planetary system is given. The previously observed characteristics of Venus and Mercury (i.e. length of day, solar orbit, temperature) are discussed. The role of the Mariner 10 space probe in gathering scientific information on the two planets is briefly described.

Venus and Mercury as planets

International Nuclear Information System (INIS)

1974-01-01

A general evolutionary history of the solar planetary system is given. The previously observed characteristics of Venus and Mercury (i.e. length of day, solar orbit, temperature) are discussed. The role of the Mariner 10 space probe in gathering scientific information on the two planets is briefly described

Finding A Planet Through the Dust

Science.gov (United States)

Kohler, Susanna

2018-05-01

Finding planets in the crowded galactic center is a difficult task, but infrared microlensing surveys give us a fighting chance! Preliminary results from such a study have already revealed a new exoplanet lurking in the dust of the galactic bulge.Detection BiasesUKIRT-2017 microlensing survey fields (blue), plotted over a map showing the galactic-plane dust extinction. The location of the newly discovered giant planet is marked with blue crosshairs. [Shvartzvald et al. 2018]Most exoplanets weve uncovered thus far were found either via transits dips in a stars light as the planet passes in front of its host star or via radial velocity wobbles of the star as the orbiting planet tugs on it. These techniques, while highly effective, introduce a selection bias in the types of exoplanets we detect: both methods tend to favor discovery of close-in, large planets orbiting small stars; these systems produce the most easily measurable signals on short timescales.For this reason, microlensing surveys for exoplanets have something new to add to the field.Search for a LensIn gravitational microlensing, we observe a background star as it is briefly magnified by a passing foreground star acting as a lens. If that foreground star hosts a planet, we observe a characteristic shape in the observed brightening of the background star, and the properties of that shape can reveal information about the foreground planet.A diagram of how planets are detected via gravitational microlensing. The detectable planet is in orbit around the foreground lens star. [NASA]This technique for planet detection is unique in its ability to explore untapped regions of exoplanet parameter space with microlensing, we can survey for planets around all different types of stars (rather than primarily small, dim ones), planets of all masses near the further-out snowlines where gas and ice giants are likely to form, and even free-floating planets.In a new study led by a Yossi Shvartzvald, a NASA postdoctoral

Hubble 2020: Outer Planet Atmospheres Legacy (OPAL) Program

Science.gov (United States)

Simon, Amy

2017-08-01

Long time base observations of the outer planets are critical in understanding the atmospheric dynamics and evolution of the gas giants. We propose yearly monitoring of each giant planet for the remainder of Hubble's lifetime to provide a lasting legacy of increasingly valuable data for time-domain studies. The Hubble Space Telescope is a unique asset to planetary science, allowing high spatial resolution data with absolute photometric knowledge. For the outer planets, gas/ice giant planets Jupiter, Saturn, Uranus and Neptune, many phenomena happen on timescales of years to decades, and the data we propose are beyond the scope of a typical GO program. Hubble is the only platform that can provide high spatial resolution global studies of cloud coloration, activity, and motion on a consistent time basis to help constrain the underlying mechanics.

Psychometric evaluation of the Spanish version of the MPI-SCI.

Science.gov (United States)

Soler, M D; Cruz-Almeida, Y; Saurí, J; Widerström-Noga, E G

2013-07-01

Postal surveys. To confirm the factor structure of the Spanish version of the MPI-SCI (MPI-SCI-S, Multidimensional Pain Inventory in the SCI population) and to test its internal consistency and construct validity in a Spanish population. Guttmann Institute, Barcelona, Spain. The MPI-SCI-S along with Spanish measures of pain intensity (Numerical Rating Scale), pain interference (Brief Pain Inventory), functional independence (Functional Independence Measure), depression (Beck Depression Inventory), locus of control (Multidimensional health Locus of Control), support (Functional Social Support Questionnaire (Duke-UNC)), psychological well-being (Psychological Global Well-Being Index) and demographic/injury characteristics were assessed in persons with spinal cord injury (SCI) and chronic pain (n=126). Confirmatory factor analysis suggested an adequate factor structure for the MPI-SCI-S. The internal consistency of the MPI-SCI-S subscales ranged from acceptable (r=0.66, Life Control) to excellent (r=0.94, Life Interference). All MPI-SCI-S subscales showed adequate construct validity, with the exception of the Negative and Solicitous Responses subscales. The Spanish version of the MPI-SCI is adequate for evaluating chronic pain impact following SCI in a Spanish-speaking population. Future studies should include additional measures of pain-related support in the Spanish-speaking SCI population.

[SciELO: method for electronic publishing].

Science.gov (United States)

Laerte Packer, A; Rocha Biojone, M; Antonio, I; Mayumi Takemaka, R; Pedroso García, A; Costa da Silva, A; Toshiyuki Murasaki, R; Mylek, C; Carvalho Reisl, O; Rocha F Delbucio, H C

2001-01-01

It describes the SciELO Methodology Scientific Electronic Library Online for electronic publishing of scientific periodicals, examining issues such as the transition from traditional printed publication to electronic publishing, the scientific communication process, the principles which founded the methodology development, its application in the building of the SciELO site, its modules and components, the tools use for its construction etc. The article also discusses the potentialities and trends for the area in Brazil and Latin America, pointing out questions and proposals which should be investigated and solved by the methodology. It concludes that the SciELO Methodology is an efficient, flexible and wide solution for the scientific electronic publishing.

SCI implementation study for LHCb data acquisition

CERN Document Server

Müller, H

1998-01-01

This paper proposes the use of SCI 1 as a scalable standard to implement the eventbuilder network between the Readout-Units and the Subfarm Controllers of LHCb. SCI [Ref 1] allows for a memory bus-like interconnection between the data sources and the CPU farm, this implies that sources can directly write data to event-buffers in the farm. This data-driven eventbuilding is enhanced by DMA engines as part of the SCI adapters at the source buffers. In general, data may be either written from the sources (event driven DMA for the full readout) or pulled from the destination (demand-driven DMA for the phased readout). A mixture of both readout architectures is possible, a second level push and a third level pull scheme could simultaneously coexist across the same physical network. Sources and destinations are interconnected via very high bandwidth SCI rings ( 4-8 Gbit/s). By using SCI switches, bandwidth scaling up to any required throughput is possible. The functionalities of a Readout Unit (RU) and a Subfarm Con...

Kepler-36: A Pair of Planets with Neighboring Orbits and Dissimilar Densities

Energy Technology Data Exchange (ETDEWEB)

Carter, J. A.; Agol, E.; Chaplin, W. J.; Basu, S.; Bedding, T. R.; Buchhave, L. A.; Christensen-Dalsgaard, J.; Deck, K. M.; Elsworth, Y.; Fabrycky, D. C.; Ford, E. B.; Fortney, J. J.; Hale, S. J.; Handberg, R.; Hekker, S.; Holman, M. J.; Huber, D.; Karoff, C.; Kawaler, S. D.; Kjeldsen, H.; Lissauer, J. J.; Lopez, E. D.; Lund, M. N.; Lundkvist, M.; Metcalfe, T. S.; Miglio, A.; Rogers, L. A.; Stello, D.; Borucki, W. J.; Bryson, S.; Christiansen, J. L.; Cochran, W. D.; Geary, J. C.; Gilliland, R. L.; Haas, M. R.; Hall, J.; Howard, A. W.; Jenkins, J. M.; Klaus, T.; Koch, D. G.; Latham, D. W.; MacQueen, P. J.; Sasselov, D.; Steffen, J. H.; Twicken, J. D.; Winn, J. N.

2012-06-21

In the Solar system the planets' compositions vary with orbital distance, with rocky planets in close orbits and lower-density gas giants in wider orbits. The detection of close-in giant planets around other stars was the first clue that this pattern is not universal, and that planets' orbits can change substantially after their formation. Here we report another violation of the orbit-composition pattern: two planets orbiting the same star with orbital distances differing by only 10%, and densities differing by a factor of 8. One planet is likely a rocky `super-Earth', whereas the other is more akin to Neptune. These planets are thirty times more closely spaced--and have a larger density contrast--than any adjacent pair of planets in the Solar system.

What Are the Treatments for Spinal Cord Injury (SCI)?

Science.gov (United States)

... What are the treatments for spinal cord injury (SCI)? Unfortunately, there are at present no known ways ... function of the nerves that remain after an SCI. SCI treatment currently focuses on preventing further injury ...

Performance of the SciBar cosmic ray telescope (SciCRT) toward the detection of high-energy solar neutrons in solar cycle 24

Science.gov (United States)

Sasai, Yoshinori; Nagai, Yuya; Itow, Yoshitaka; Matsubara, Yutaka; Sako, Takashi; Lopez, Diego; Itow, Tsukasa; Munakata, Kazuoki; Kato, Chihiro; Kozai, Masayoshi; Miyazaki, Takahiro; Shibata, Shoichi; Oshima, Akitoshi; Kojima, Hiroshi; Tsuchiya, Harufumi; Watanabe, Kyoko; Koi, Tatsumi; Valdés-Galicia, Jose Francisco; González, Luis Xavier; Ortiz, Ernesto; Musalem, Octavio; Hurtado, Alejandro; Garcia, Rocio; Anzorena, Marcos

2014-12-01

We plan to observe solar neutrons at Mt. Sierra Negra (4,600 m above sea level) in Mexico using the SciBar detector. This project is named the SciBar Cosmic Ray Telescope (SciCRT). The main aims of the SciCRT project are to observe solar neutrons to study the mechanism of ion acceleration on the surface of the sun and to monitor the anisotropy of galactic cosmic-ray muons. The SciBar detector, a fully active tracker, is composed of 14,848 scintillator bars, whose dimension is 300 cm × 2.5 cm × 1.3 cm. The structure of the detector enables us to obtain the particle trajectory and its total deposited energy. This information is useful for the energy reconstruction of primary neutrons and particle identification. The total volume of the detector is 3.0 m × 3.0 m × 1.7 m. Since this volume is much larger than the solar neutron telescope (SNT) in Mexico, the detection efficiency of the SciCRT for neutrons is highly enhanced. We performed the calibration of the SciCRT at Instituto Nacional de Astrofisica, Optica y Electronica (INAOE) located at 2,150 m above sea level in Mexico in 2012. We installed the SciCRT at Mt. Sierra Negra in April 2013 and calibrated this detector in May and August 2013. We started continuous observation in March 2014. In this paper, we report the detector performance as a solar neutron telescope and the current status of the SciCRT.

Experiences using SciPy for computer vision research

Energy Technology Data Exchange (ETDEWEB)

Eads, Damian R [Los Alamos National Laboratory; Rosten, Edward J [Los Alamos National Laboratory

2008-01-01

SciPy is an effective tool suite for prototyping new algorithms. We share some of our experiences using it for the first time to support our research in object detection. SciPy makes it easy to integrate C code, which is essential when algorithms operating on large data sets cannot be vectorized. The universality of Python, the language in which SciPy was written, gives the researcher access to a broader set of non-numerical libraries to support GUI development, interface with databases, manipulate graph structures. render 3D graphics, unpack binary files, etc. Python's extensive support for operator overloading makes SciPy's syntax as succinct as its competitors, MATLAB, Octave, and R. More profoundly, we found it easy to rework research code written with SciPy into a production application, deployable on numerous platforms.

A millennium approach to data acquisition: SCI and PCI

International Nuclear Information System (INIS)

Mueller, Hans; Bogaerts, A.; Lindenstruth, V.

1996-01-01

The international SCI standard IEEE/ANSI 1596 a is on its way to become the computer interconnect of the year 2000 since for a first time, low latency desktop multiprocessing and cluster computing can be implemented at low cost. The PCI bus is todays's dominating local bus extension for all major computer platforms as well as buses like VMEbus. PCI is a self configuring memory and I/O system for peripheral components with a hierarchical architecture. SCI is a scalable, bus-like interconnect for distributed processors and memories. It allows for optionally coherent data caching and assures error free data delivery. First measurement with commercial SCI products (SBUS-SCI) confirm simulations that SCI can handle even the highest data rates of LHC experiments. The event builder layer for a millennium very high rate DAQ system can therefore be viewed as a SCI network (bridges, cables and switches) interfaced between PCI buses on the front end (VME b ) side and on the processor farm Multi-CPU) side. Such a combination of SCI and PCI enables PCI-PCI memory access, transparently across SCI. It also allows for a novel, low level trigger technique: the trigger algorithm can access VME data buffers with bus-like latencies like local memory, full data transfers become redundant. The first prototype of a PCI-SCI bridge for DAQ is presented as starting point for a test system with built-in scalability. (author)

Development and initial evaluation of the SCI-FI/AT.

Science.gov (United States)

Jette, Alan M; Slavin, Mary D; Ni, Pengsheng; Kisala, Pamela A; Tulsky, David S; Heinemann, Allen W; Charlifue, Susie; Tate, Denise G; Fyffe, Denise; Morse, Leslie; Marino, Ralph; Smith, Ian; Williams, Steve

2015-05-01

To describe the domain structure and calibration of the Spinal Cord Injury Functional Index for samples using Assistive Technology (SCI-FI/AT) and report the initial psychometric properties of each domain. Cross sectional survey followed by computerized adaptive test (CAT) simulations. Inpatient and community settings. A sample of 460 adults with traumatic spinal cord injury (SCI) stratified by level of injury, completeness of injury, and time since injury. None SCI-FI/AT RESULTS: Confirmatory factor analysis (CFA) and Item response theory (IRT) analyses identified 4 unidimensional SCI-FI/AT domains: Basic Mobility (41 items) Self-care (71 items), Fine Motor Function (35 items), and Ambulation (29 items). High correlations of full item banks with 10-item simulated CATs indicated high accuracy of each CAT in estimating a person's function, and there was high measurement reliability for the simulated CAT scales compared with the full item bank. SCI-FI/AT item difficulties in the domains of Self-care, Fine Motor Function, and Ambulation were less difficult than the same items in the original SCI-FI item banks. With the development of the SCI-FI/AT, clinicians and investigators have available multidimensional assessment scales that evaluate function for users of AT to complement the scales available in the original SCI-FI.

Planetary protection protecting earth and planets against alien microbes

International Nuclear Information System (INIS)

Leys, N.

2006-01-01

Protecting Earth and planets against the invasion of 'alien life forms' is not military science fiction, but it is the peaceful daily job of engineers and scientists of space agencies. 'Planetary Protection' is preventing microbial contamination of both the target planet and the Earth when sending robots on interplanetary space mission. It is important to preserve the 'natural' conditions of other planets and to not bring with robots 'earthly microbes' (forward contamination) when looking for 'spores of extra terrestrial life'. The Earth and its biosphere must be protected from potential extraterrestrial biological contamination when returning samples of other planets to the Earth (backward contamination). The NASA-Caltech Laboratory for Planetary Protection of Dr. Kasthuri Venkateswaran at the Jet Propulsion Laboratory (JPL) (California, USA) routinely monitors and characterizes the microbes of NASA spacecraft assembly rooms and space robots prior to flight. They have repeatedly isolated Cupriavidus and Ralstonia strains pre-flight from spacecraft assembly rooms (floor and air) and surfaces of space robots such as the Mars Odyssey Orbiter (La Duc et al., 2003). Cupriavidus and Ralstonia strains have also been found in-flight, in ISS cooling water and Shuttle drinking water (Venkateswaran et al., Pyle et al., Ott et al., all unpublished). The main objective of this study is to characterise the Cupriavidus and Ralstonia strains isolated at JPL and compare them to the Cupriavidus metallidurans CH34T model strain, isolated from a Belgian contaminated soil and studied since 25 years at SCK-CEN and to enhance our knowledge by performing additional tests at JPL and gathering information regarding the environmental conditions and the cleaning and isolation methods used in such spacecraft assembling facilities

The search for life on Earth and other planets.

Science.gov (United States)

Gross, Michael

2012-04-10

As the NASA rover Curiosity approaches Mars on its quest to look for signs of past or present life there and sophisticated instruments like the space telescopes Kepler and CoRoT keep discovering additional, more Earth-like planets orbiting distant stars, science faces the question of how to spot life on other planets. Even here on Earth biotopes remain to be discovered and explored.

Simulated JWST/NIRISS Transit Spectroscopy of Anticipated Tess Planets Compared to Select Discoveries from Space-based and Ground-based Surveys

Science.gov (United States)

Louie, Dana R.; Deming, Drake; Albert, Loic; Bouma, L. G.; Bean, Jacob; Lopez-Morales, Mercedes

2018-04-01

The Transiting Exoplanet Survey Satellite (TESS) will embark in 2018 on a 2 year wide-field survey mission, discovering over a thousand terrestrial, super-Earth and sub-Neptune-sized exoplanets ({R}pl}≤slant 4 {R}\\oplus ) potentially suitable for follow-up observations using the James Webb Space Telescope (JWST). This work aims to understand the suitability of anticipated TESS planet discoveries for atmospheric characterization by JWST’s Near InfraRed Imager and Slitless Spectrograph (NIRISS) by employing a simulation tool to estimate the signal-to-noise (S/N) achievable in transmission spectroscopy. We applied this tool to Monte Carlo predictions of the TESS expected planet yield and then compared the S/N for anticipated TESS discoveries to our estimates of S/N for 18 known exoplanets. We analyzed the sensitivity of our results to planetary composition, cloud cover, and presence of an observational noise floor. We find that several hundred anticipated TESS discoveries with radii 1.5 {R}\\oplus R}pl}≤slant 2.5 {R}\\oplus will produce S/N higher than currently known exoplanets in this radius regime, such as K2-3b or K2-3c. In the terrestrial planet regime, we find that only a few anticipated TESS discoveries will result in higher S/N than currently known exoplanets, such as the TRAPPIST-1 planets, GJ1132b, and LHS1140b. However, we emphasize that this outcome is based upon Kepler-derived occurrence rates, and that co-planar compact multi-planet systems (e.g., TRAPPIST-1) may be under-represented in the predicted TESS planet yield. Finally, we apply our calculations to estimate the required magnitude of a JWST follow-up program devoted to mapping the transition region between hydrogen-dominated and high molecular weight atmospheres. We find that a modest observing program of between 60 and 100 hr of charged JWST time can define the nature of that transition (e.g., step function versus a power law).

Opening Comments: SciDAC 2008

Science.gov (United States)

Strayer, Michael

2008-07-01

Welcome to Seattle and the 2008 SciDAC Conference. This conference, the fourth in the series, is a continuation of the PI meetings we first began under SciDAC-1. I would like to start by thanking the organizing committee, and Rick Stevens in particular, for organizing this year's meeting. This morning I would like to look briefly at SciDAC, to give you a brief history of SciDAC and also look ahead to see where we plan to go over the next few years. I think the best description of SciDAC, at least the simulation part, comes from a quote from Dr Ray Orbach, DOE's Under Secretary for Science and Director of the Office of Science. In an interview that appeared in the SciDAC Review magazine, Dr Orbach said, `SciDAC is unique in the world. There isn't any other program like it anywhere else, and it has the remarkable ability to do science by bringing together physical scientists, mathematicians, applied mathematicians, and computer scientists who recognize that computation is not something you do at the end, but rather it needs to be built into the solution of the very problem that one is addressing'. Of course, that is extended not just to physical scientists, but also to biological scientists. This is a theme of computational science, this partnership among disciplines, which goes all the way back to the early 1980s and Ken Wilson. It's a unique thread within the Department of Energy. SciDAC-1, launched around the turn of the millennium, created a new generation of scientific simulation codes. It advocated building out mathematical and computing system software in support of science and a new collaboratory software environment for data. The original concept for SciDAC-1 had topical centers for the execution of the various science codes, but several corrections and adjustments were needed. The ASCR scientific computing infrastructure was also upgraded, providing the hardware facilities for the program. The computing facility that we had at that time was the big 3

Fee-based services in sci-tech libraries

CERN Document Server

Mount, Ellis

2013-01-01

This timely and important book explores how fee-based services have developed in various types of sci-tech libraries. The authoritative contributors focus on the current changing financial aspects of the sci-tech library operation and clarify for the reader how these changes have brought about conditions in which traditional methods of funding are no longer adequate. What new options are open and how they are best being applied in today's sci-tech libraries is fully and clearly explained and illustrated. Topics explored include cost allocation and cost recovery, fees for computer searching, an

ALMOST ALL OF KEPLER'S MULTIPLE-PLANET CANDIDATES ARE PLANETS

International Nuclear Information System (INIS)

Lissauer, Jack J.; Rowe, Jason F.; Bryson, Stephen T.; Howell, Steve B.; Jenkins, Jon M.; Kinemuchi, Karen; Koch, David G.; Marcy, Geoffrey W.; Adams, Elisabeth; Fressin, Francois; Geary, John; Holman, Matthew J.; Ragozzine, Darin; Buchhave, Lars A.; Ciardi, David R.; Cochran, William D.; Fabrycky, Daniel C.; Ford, Eric B.; Morehead, Robert C.; Gilliland, Ronald L.

2012-01-01

We present a statistical analysis that demonstrates that the overwhelming majority of Kepler candidate multiple transiting systems (multis) indeed represent true, physically associated transiting planets. Binary stars provide the primary source of false positives among Kepler planet candidates, implying that false positives should be nearly randomly distributed among Kepler targets. In contrast, true transiting planets would appear clustered around a smaller number of Kepler targets if detectable planets tend to come in systems and/or if the orbital planes of planets encircling the same star are correlated. There are more than one hundred times as many Kepler planet candidates in multi-candidate systems as would be predicted from a random distribution of candidates, implying that the vast majority are true planets. Most of these multis are multiple-planet systems orbiting the Kepler target star, but there are likely cases where (1) the planetary system orbits a fainter star, and the planets are thus significantly larger than has been estimated, or (2) the planets orbit different stars within a binary/multiple star system. We use the low overall false-positive rate among Kepler multis, together with analysis of Kepler spacecraft and ground-based data, to validate the closely packed Kepler-33 planetary system, which orbits a star that has evolved somewhat off of the main sequence. Kepler-33 hosts five transiting planets, with periods ranging from 5.67 to 41 days.

MathSci

OpenAIRE

De Robbio, Antonella

1997-01-01

This paper shows the prestigious mathematics database MathSci, produced by American Mathematical Society (AMS). It is an indexing resource that deals with the whole literature about mathematics. The subject involved in referred to mathematical sciences and others relating such as Statistics, Information science, Operative research and Mathematics Physics. Moreover it indexes sciences related to applied mathematics such as Astronomy, Astrophysics, Biology, Compartmental Sciences, Thermodyn...

Constraints on planet formation from Kepler’s multiple planet systems

Science.gov (United States)

Quintana, Elisa V.

2015-01-01

The recent haul of hundreds of multiple planet systems discovered by Kepler provides a treasure trove of new clues for planet formation theories. The substantial amount of protoplanetary disk mass needed to form the most commonly observed multi-planet systems - small (Earth-sized to mini-Neptune-sized) planets close to their stars - argues against pure in situ formation and suggests that the planets in these systems must have undergone some form of migration. I will present results from numerical simulations of terrestrial planet formation that aim to reproduce the sizes and architecture of Kepler's multi-planet systems, and will discuss the observed resonances and giant planets (or the lack thereof) associated with these systems.

Innocent Bystanders: Orbital Dynamics of Exomoons During Planet–Planet Scattering

Science.gov (United States)

Hong, Yu-Cian; Raymond, Sean N.; Nicholson, Philip D.; Lunine, Jonathan I.

2018-01-01

Planet–planet scattering is the leading mechanism to explain the broad eccentricity distribution of observed giant exoplanets. Here we study the orbital stability of primordial giant planet moons in this scenario. We use N-body simulations including realistic oblateness and evolving spin evolution for the giant planets. We find that the vast majority (∼80%–90% across all our simulations) of orbital parameter space for moons is destabilized. There is a strong radial dependence, as moons past ∼ 0.1 {R}{Hill} are systematically removed. Closer-in moons on Galilean-moon-like orbits (<0.04 R Hill) have a good (∼20%–40%) chance of survival. Destabilized moons may undergo a collision with the star or a planet, be ejected from the system, be captured by another planet, be ejected but still orbiting its free-floating host planet, or survive on heliocentric orbits as “planets.” The survival rate of moons increases with the host planet mass but is independent of the planet’s final (post-scattering) orbits. Based on our simulations, we predict the existence of an abundant galactic population of free-floating (former) moons.

Role of the lifetime of ring current particles on the solar wind-magnetosphere power transfer during the intense geomagnetic storm of 28 August 1978

International Nuclear Information System (INIS)

Gonzalez, W.D.; Gonzalez, A.L.C.; Lee, L.C.

1990-01-01

For the intense magnetic storms of 28 August 1978 it is shown that the power transfer from the solar wind to the magnetosphere is well represented by the expression obtained by Vasyliunas et al. (1982, Planet. Space Sci. 30, 359) from dimensional analysis, but this representation becomes improved when such an expression is modified by a factor due to an influence of the lifetime of ring current particles as suggested by Lee and Akasofu (1984, Planet. Space Sci. 32, 1423). During a steady state regime of the ring current evolution of this storm, our study suggests that the power transfer depends on the solar wind density, the transverse component of the IMF (Interplanetary magnetic field) (with respect to the Sun-Earth line) and also, explicitly, on the time constant for ring current energy decay, but not on the solar wind speed. (author)

Nearby Red Dwarfs are Sexy for Planets and Life

Science.gov (United States)

Henry, T. J.; Jao, W.-C.; Subasavage, J. P.; RECONS Team

2005-12-01

The RECONS group continues to discover many nearby red dwarfs in the southern sky through a combination of proper motion surveys, literature review, and ultimately, our parallax program CTIOPI. Already, we have measured the first accurate parallaxes for 11 of the nearest 100 stellar systems, including four within 5 parsecs of the Sun. These nearby red dwarfs are prime candidates for NASA's Space Interferometry Mission (SIM) because the astrometric perturbations are largest for planets orbiting stars of low mass that are nearby. In addition, new multiple red dwarf systems can be targeted for mass determinations, thereby providing points on a comprehensive mass-luminosity relation for the most populous members of the Galaxy. Recent atmospheric modeling of planets orbiting red dwarfs indicates that even if the planets are tidally locked, heat distribution is highly effective in keeping the worlds balmy over the entire surface. Red dwarfs are therefore "back on the table" as viable hosts of life-bearing planets. Given their ubiquity, red dwarfs are being seriously considered as prime SETI targets, and will allow us to answer not only the question "Are We Alone?" but "Just How Alone Are We?" This work has been supported by the National Science Foundation, NASA's Space Interferometry Mission, and Georgia State University.

The Outer Planets and their Moons Comparative Studies of the Outer Planets prior to the Exploration of the Saturn System by Cassini-Huygens

CERN Document Server

Encrenaz, T; Owen, T. C; Sotin, C

2005-01-01

This volume gives an integrated summary of the science related to the four giant planets in our solar system. It is the result of an ISSI workshop on «A comparative study of the outer planets before the exploration of Saturn by Cassini-Huygens» which was held at ISSI in Bern on January 12-16, 2004. Representatives of several scientific communities, such as planetary scientists, astronomers, space physicists, chemists and astrobiologists have met with the aim to review the knowledge on four major themes: (1) the study of the formation and evolution processes of the outer planets and their satellites, beginning with the formation of compounds and planetesimals in the solar nebula, and the subsequent evolution of the interiors of the outer planets, (2) a comparative study of the atmospheres of the outer planets and Titan, (3) the study of the planetary magnetospheres and their interactions with the solar wind, and (4) the formation and properties of satellites and rings, including their interiors, surfaces, an...

Complete spinal cord injury (SCI) transforms how brain derived neurotrophic factor (BDNF) affects nociceptive sensitization.

Science.gov (United States)

Huang, Yung-Jen; Lee, Kuan H; Grau, James W

2017-02-01

Noxious stimulation can induce a lasting increase in neural excitability within the spinal cord (central sensitization) that can promote pain and disrupt adaptive function (maladaptive plasticity). Brain-derived neurotrophic factor (BDNF) is known to regulate the development of plasticity and has been shown to impact the development of spinally-mediated central sensitization. The latter effect has been linked to an alteration in GABA-dependent inhibition. Prior studies have shown that, in spinally transected rats, exposure to regular (fixed spaced) stimulation can counter the development of maladaptive plasticity and have linked this effect to an up-regulation of BDNF. Here it is shown that application of the irritant capsaicin to one hind paw induces enhanced mechanical reactivity (EMR) after spinal cord injury (SCI) and that the induction of this effect is blocked by pretreatment with fixed spaced shock. This protective effect was eliminated if rats were pretreated with the BDNF sequestering antibody TrkB-IgG. Intrathecal (i.t.) application of BDNF prevented, but did not reverse, capsaicin-induced EMR. BDNF also attenuated cellular indices (ERK and pERK expression) of central sensitization after SCI. In uninjured rats, i.t. BDNF enhanced, rather than attenuated, capsaicin-induced EMR and ERK/pERK expression. These opposing effects were related to a transformation in GABA function. In uninjured rats, BDNF reduced membrane-bound KCC2 and the inhibitory effect of the GABA A agonist muscimol. After SCI, BDNF increased KCC2 expression, which would help restore GABAergic inhibition. The results suggest that SCI transforms how BDNF affects GABA function and imply that the clinical usefulness of BDNF will depend upon the extent of fiber sparing. Copyright © 2016 Elsevier Inc. All rights reserved.

Basics of SCI Rehabilitation

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Full Text Available ... Living with SCI Personal Experiences by Topic Resources Peer ... Injuries Spinal Cord Injury 101 David Chen, MD Preventing Pressure Sores Mary Zeigler, MS Transition from Hospital to ...

How to build a planet

Science.gov (United States)

Preston, Louisa

2017-12-01

It is a difficult project to tackle, in a book - the subject of exoplanets - as it is one of the fastest-moving branches of planetary science. In The Planet Factory Elizabeth Tasker, an astrophysicist at Japan's JAXA space agency, has bravely taken on the role of navigator for this incredible journey of planetary discovery, and the book does not disappoint.

Opening Comments: SciDAC 2009

Science.gov (United States)

Strayer, Michael

2009-07-01

new and novel algorithm to produce results up to 400 times faster than a similar application, and was recognized with a prize for algorithm innovation—a remarkable achievement. Day one of our conference will include examples of petascale science enabled at the OLCF. Although Jaguar has not been officially commissioned, it has gone through its acceptance tests, and during its shakedown phase there have been pioneer applications used for the acceptance tests, and they are running at scale. These include applications in the areas of astrophysics, biology, chemistry, combustion, fusion, geosciences, materials science, nuclear energy and nuclear physics. We also have a whole compendium of science we do at our facilities; these have been documented and reviewed at our last SciDAC conference. Many of these were highlighted in our Breakthroughs Report. One session at this week's conference will feature a cross-section of these breakthroughs. In the area of scalable electromagnetic simulations, the Auxiliary-space Maxwell Solver (AMS) uses specialized finite element discretizations and multigrid-based techniques, which decompose the original problem into easier-to-solve subproblems. Congratulations to the mathematicians on this. Another application on the list of breakthroughs was the authentication of PETSc, which provides scalable solvers used in many DOE applications and has solved problems with over 3 billion unknowns and scaled to over 16,000 processors on DOE leadership-class computers. This is becoming a very versatile and useful toolkit to achieve performance at scale. With the announcement of SIAM's first class of Fellows, we are remarkably well represented. Of the group of 191, more than 40 of these Fellows are in the 'DOE space.' We are so delighted that SIAM has recognized them for their many achievements. In the coming months, we will illustrate our leadership in applied math and computer science by looking at our contributions in the areas of programming models

Doppler spectroscopy as a path to the detection of Earth-like planets.

Science.gov (United States)

Mayor, Michel; Lovis, Christophe; Santos, Nuno C

2014-09-18

Doppler spectroscopy was the first technique used to reveal the existence of extrasolar planetary systems hosted by solar-type stars. Radial-velocity surveys led to the detection of a rich population of super-Earths and Neptune-type planets. The numerous detected systems revealed a remarkable diversity. Combining Doppler measurements with photometric observations of planets transiting their host stars further provides access to the planet bulk density, a first step towards comparative exoplanetology. The development of new high-precision spectrographs and space-based facilities will ultimately lead us to characterize rocky planets in the habitable zone of our close stellar neighbours.

Infrared and Raman spectroscopy on synthetic glasses as analogues of planetary surfaces.

Science.gov (United States)

Weber, Iris; Morlok, Andreas; Klemme, Stephan; Dittmer, Isabelle; Stojic, Aleksandra N.; Hiesinger, Harald; Sohn, Martin; Helbert, Jörn

2015-04-01

produced, based on the composition of the Ca- and Mg-rich and Al-poor G1 region identified on Mercury with the X-ray spectrometer on MESSENGER [7]. For in situ mid-IR specular reflectance analyses, a Bruker Hyperion 2000 System with a (1000×1000) µm2 sized aperture was used. A Bruker Vertex 70 IR system with a MCT detector was applied for analyses of areas >>1 mm under near vacuum conditions. Raman spectra will be collected with an OceanOptics IDR-Micro-532 spectrometer. Our results show that the micro-FTIR reflectance data of two glassy regions provide a smooth feature that is typical for amorphous materials. Only very weak sharper crystalline bands occur on top of the feature at 10.1-10.2 µm and 10.5-10.6 µm. These bands are probably resulting from crystalline forsterite within a glassy matrix, because the crystalline bands at 10.1 and 10.5 µm are characteristic for nearly pure forsterite [8]. The Christiansen feature is at 8.2 µm. The spectrum of a larger region is basically a 'bulk' spectrum. Achieved under near-vacuum conditions this spectrum displays essentially similar characteristics. References: [1] Maturilli A. (2006) Planet. Space Sci. 54, 1057-1064. [2] Helbert J. and Maturilli A. (2009) Earth Planet. Sci. Lett. 285, 347-354. [3] Benkhoff, J. et al. (2010) Planet. Space Sci. 58, 2-20. [4] Hiesinger H. et al. (2010) Planet. Space Sci. 58, 144-165. [5] Maturilli J. (2008) Planet. Space Sci. 56, 420-425. [6] Vago et al. (2012) Mars Concepts, Houston. [3] Hamilton V.E. (2010) Chem. Erde, 70, 7-33. [7] Charlier B. et al. (2013) Earth Planet. Sci. Lett. 363, 50-60.

Orgasm and SCI: what do we know?

Science.gov (United States)

Alexander, Marcalee; Marson, Lesley

2018-06-01

narrative review OBJECTIVES: To determine the percentage of persons with SCI able to achieve orgasm and ejaculation, the associations between ejaculation and orgasm and the subjective and autonomic findings during these events, and the potential benefits with regards to spasticity. Two American medical centers METHODS: Data bases were searched for the terms orgasm and SCI and ejaculation and SCI. Search criteria were human studies published in English from 1990 to 12/2/2016. Approximately 50% of sexually active men and women report orgasmic ability after SCI. There is a relative inability of persons with complete lower motor neuron injuries affecting the sacral segments to achieve orgasm. Time to orgasm is longer in persons with SCIs than able-bodied (AB) persons. With orgasm, elevated blood pressure (BP) occurs after SCI in a similar fashion to AB persons. With penile vibratory stimulation and electroejaculation, BP elevation is common and prophylaxis is recommended in persons with injuries at T6 and above. Dry orgasm occurs approximately 13% of times in males. Midodrine, vibratory stimulation, clitoral vacuum suction, and 4-aminopyridine may improve orgasmic potential. Depending on level and severity of injury, persons with SCIs can achieve orgasm. Sympathetically mediated changes occur during sexual response with culmination at orgasm. Future research should address benefits of orgasm. Additionally, inherent biases associated with studying orgasm must be considered.

CoRoT’s first seven planets: An overview*

Directory of Open Access Journals (Sweden)

Barge P.

2011-07-01

Full Text Available The up to 150 day uninterrupted high-precision photometry of about 100000 stars – provided so far by the exoplanet channel of the CoRoT space telescope – gave a new perspective on the planet population of our galactic neighbourhood. The seven planets with very accurate parameters widen the range of known planet properties in almost any respect. Giant planets have been detected at low metallicity, rapidly rotating and active, spotted stars. CoRoT-3 populated the brown dwarf desert and closed the gap of measured physical properties between standard giant planets and very low mass stars. CoRoT extended the known range of planet masses down-to 5 Earth masses and up to 21 Jupiter masses, the radii to less than 2 Earth radii and up to the most inflated hot Jupiter found so far, and the periods of planets discovered by transits to 9 days. Two CoRoT planets have host stars with the lowest content of heavy elements known to show a transit hinting towards a different planet-host-star-metallicity relation then the one found by radial-velocity search programs. Finally the properties of the CoRoT-7b prove that terrestrial planets with a density close to Earth exist outside the Solar System. The detection of the secondary transit of CoRoT-1 at the 10−5-level and the very clear detection of the 1.7 Earth radii of CoRoT-7b at 3.5 10−4 relative flux are promising evidence of CoRoT being able to detect even smaller, Earth sized planets.

Basics of SCI Rehabilitation

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Full Text Available ... How Peer Counseling Works Julie Gassaway, MS, RN Pediatric Injuries Pediatric Spinal Cord Injury 101 Lawrence Vogel, MD The Basics of Pediatric SCI Rehabilitation Sara Klaas, MSW Transitions for Children ...

Basics of SCI Rehabilitation

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Full Text Available ... Medical Experts People Living with SCI Personal Experiences by Topic Resources Peer ... Injuries Spinal Cord Injury 101 David Chen, MD Preventing Pressure Sores Mary Zeigler, MS Transition from Hospital to ...

The habitability of planets orbiting M-dwarf stars

Science.gov (United States)

Shields, Aomawa L.; Ballard, Sarah; Johnson, John Asher

2016-12-01

The prospects for the habitability of M-dwarf planets have long been debated, due to key differences between the unique stellar and planetary environments around these low-mass stars, as compared to hotter, more luminous Sun-like stars. Over the past decade, significant progress has been made by both space- and ground-based observatories to measure the likelihood of small planets to orbit in the habitable zones of M-dwarf stars. We now know that most M dwarfs are hosts to closely-packed planetary systems characterized by a paucity of Jupiter-mass planets and the presence of multiple rocky planets, with roughly a third of these rocky M-dwarf planets orbiting within the habitable zone, where they have the potential to support liquid water on their surfaces. Theoretical studies have also quantified the effect on climate and habitability of the interaction between the spectral energy distribution of M-dwarf stars and the atmospheres and surfaces of their planets. These and other recent results fill in knowledge gaps that existed at the time of the previous overview papers published nearly a decade ago by Tarter et al. (2007) and Scalo et al. (2007). In this review we provide a comprehensive picture of the current knowledge of M-dwarf planet occurrence and habitability based on work done in this area over the past decade, and summarize future directions planned in this quickly evolving field.

Preface: SciDAC 2005

Science.gov (United States)

Mezzacappa, Anthony

2005-01-01

On 26-30 June 2005 at the Grand Hyatt on Union Square in San Francisco several hundred computational scientists from around the world came together for what can certainly be described as a celebration of computational science. Scientists from the SciDAC Program and scientists from other agencies and nations were joined by applied mathematicians and computer scientists to highlight the many successes in the past year where computation has led to scientific discovery in a variety of fields: lattice quantum chromodynamics, accelerator modeling, chemistry, biology, materials science, Earth and climate science, astrophysics, and combustion and fusion energy science. Also highlighted were the advances in numerical methods and computer science, and the multidisciplinary collaboration cutting across science, mathematics, and computer science that enabled these discoveries. The SciDAC Program was conceived and funded by the US Department of Energy Office of Science. It is the Office of Science's premier computational science program founded on what is arguably the perfect formula: the priority and focus is science and scientific discovery, with the understanding that the full arsenal of `enabling technologies' in applied mathematics and computer science must be brought to bear if we are to have any hope of attacking and ultimately solving today's computational Grand Challenge problems. The SciDAC Program has been in existence for four years, and many of the computational scientists funded by this program will tell you that the program has given them the hope of addressing their scientific problems in full realism for the very first time. Many of these scientists will also tell you that SciDAC has also fundamentally changed the way they do computational science. We begin this volume with one of DOE's great traditions, and core missions: energy research. As we will see, computation has been seminal to the critical advances that have been made in this arena. Of course, to

Modeling circumbinary planets: The case of Kepler-38

Science.gov (United States)

Kley, Wilhelm; Haghighipour, Nader

2014-04-01

Context. Recently, a number of planets orbiting binary stars have been discovered by the Kepler space telescope. In a few systems the planets reside close to the dynamical stability limit. Owing to the difficulty of forming planets in such close orbits, it is believed that they have formed farther out in the disk and migrated to their present locations. Aims: Our goal is to construct more realistic models of planet migration in circumbinary disks and to determine the final position of these planets more accurately. In our work, we focus on the system Kepler-38 where the planet is close to the stability limit. Methods: The evolution of the circumbinary disk is studied using two-dimensional hydrodynamical simulations. We study locally isothermal disks as well as more realistic models that include full viscous heating, radiative cooling from the disk surfaces, and radiative diffusion in the disk midplane. After the disk has been brought into a quasi-equilibrium state, a 115 Earth-mass planet is embedded and its evolution is followed. Results: In all cases the planets stop inward migration near the inner edge of the disk. In isothermal disks with a typical disk scale height of H/r = 0.05, the final outcome agrees very well with the observed location of planet Kepler-38b. For the radiative models, the disk thickness and location of the inner edge is determined by the mass in the system. For surface densities on the order of 3000 g/cm2 at 1 AU, the inner gap lies close to the binary and planets stop in the region between the 5:1 and 4:1 mean-motion resonances with the binary. A model with a disk with approximately a quarter of the mass yields a final position very close to the observed one. Conclusions: For planets migrating in circumbinary disks, the final position is dictated by the structure of the disk. Knowing the observed orbits of circumbinary planets, radiative disk simulations with embedded planets can provide important information on the physical state of the

EFFECTS OF DYNAMICAL EVOLUTION OF GIANT PLANETS ON SURVIVAL OF TERRESTRIAL PLANETS

International Nuclear Information System (INIS)

Matsumura, Soko; Ida, Shigeru; Nagasawa, Makiko

2013-01-01

The orbital distributions of currently observed extrasolar giant planets allow marginally stable orbits for hypothetical, terrestrial planets. In this paper, we propose that many of these systems may not have additional planets on these ''stable'' orbits, since past dynamical instability among giant planets could have removed them. We numerically investigate the effects of early evolution of multiple giant planets on the orbital stability of the inner, sub-Neptune-like planets which are modeled as test particles, and determine their dynamically unstable region. Previous studies have shown that the majority of such test particles are ejected out of the system as a result of close encounters with giant planets. Here, we show that secular perturbations from giant planets can remove test particles at least down to 10 times smaller than their minimum pericenter distance. Our results indicate that, unless the dynamical instability among giant planets is either absent or quiet like planet-planet collisions, most test particles down to ∼0.1 AU within the orbits of giant planets at a few AU may be gone. In fact, out of ∼30% of survived test particles, about three quarters belong to the planet-planet collision cases. We find a good agreement between our numerical results and the secular theory, and present a semi-analytical formula which estimates the dynamically unstable region of the test particles just from the evolution of giant planets. Finally, our numerical results agree well with the observations, and also predict the existence of hot rocky planets in eccentric giant planet systems.

Basics of SCI Rehabilitation

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Full Text Available ... SCI Rehabilitation Donald Peck Leslie, MD Adjusting to Social Life in a Wheelchair Lisa Rosen, MS Spasticity, ... OT Anne Bryden, OT The Role of the Social Worker after Spinal Cord Injury Patti Rogers, SW ...

PLANET HUNTERS: ASSESSING THE KEPLER INVENTORY OF SHORT-PERIOD PLANETS

International Nuclear Information System (INIS)

Schwamb, Megan E.; Lintott, Chris J.; Lynn, Stuart; Smith, Arfon M.; Simpson, Robert J.; Fischer, Debra A.; Giguere, Matthew J.; Brewer, John M.; Parrish, Michael; Schawinski, Kevin

2012-01-01

We present the results from a search of data from the first 33.5 days of the Kepler science mission (Quarter 1) for exoplanet transits by the Planet Hunters citizen science project. Planet Hunters enlists members of the general public to visually identify transits in the publicly released Kepler light curves via the World Wide Web. Over 24,000 volunteers reviewed the Kepler Quarter 1 data set. We examine the abundance of ≥2 R ⊕ planets on short-period ( ⊕ Planet Hunters ≥85% efficient at identifying transit signals for planets with periods less than 15 days for the Kepler sample of target stars. Our high efficiency rate for simulated transits along with recovery of the majority of Kepler ≥4 R ⊕ planets suggests that the Kepler inventory of ≥4 R ⊕ short-period planets is nearly complete.

Kepler Planets Tend to Have Siblings of the Same Size

Science.gov (United States)

Kohler, Susanna

2017-11-01

After 8.5 years of observations with the Kepler space observatory, weve discovered a large number of close-in, tightly-spaced, multiple-planet systems orbiting distant stars. In the process, weve learned a lot about the properties about these systems and discovered some unexpected behavior. A new study explores one of the properties that has surprised us: planets of the same size tend to live together.Orbital architectures for 25 of the authors multiplanet systems. The dots are sized according to the planets relative radii and colored according to mass. Planets of similar sizes and masses tend to live together in the same system. [Millholland et al. 2017]Ordering of SystemsFrom Keplers observations of extrasolar multiplanet systems, we have seen that the sizes of planets in a given system arent completely random. Systems that contain a large planet, for example, are more likely to contain additional large planets rather than additional planets of random size. So though there is a large spread in the radii weve observed for transiting exoplanets, the spread within any given multiplanet system tends to be much smaller.This odd behavior has led us to ask whether this clustering occurs not just for radius, but also for mass. Since the multiplanet systems discovered by Kepler most often contain super-Earths and mini-Neptunes, which have an extremely large spread in densities, the fact that two such planets have similar radii does not guarantee that they have similar masses.If planets dont cluster in mass within a system, this would raise the question of why planets coordinate only their radii within a given system. If they do cluster in mass, it implies that planets within the same system tend to have similar densities, potentially allowing us to predict the sizes and masses of planets we might find in a given system.Insight into MassesLed by NSF graduate research fellow Sarah Millholland, a team of scientists at Yale University used recently determined masses for

HABITABLE PLANETS ECLIPSING BROWN DWARFS: STRATEGIES FOR DETECTION AND CHARACTERIZATION

International Nuclear Information System (INIS)

Belu, Adrian R.; Selsis, Franck; Raymond, Sean N.; Bolmont, Emeline; Pallé, Enric; Street, Rachel; Sahu, D. K.; Anupama, G. C.; Von Braun, Kaspar; Figueira, Pedro; Ribas, Ignasi

2013-01-01

Given the very close proximity of their habitable zones, brown dwarfs (BDs) represent high-value targets in the search for nearby transiting habitable planets that may be suitable for follow-up occultation spectroscopy. In this paper, we develop search strategies to find habitable planets transiting BDs depending on their maximum habitable orbital period (P HZ o ut ). Habitable planets with P HZ o ut shorter than the useful duration of a night (e.g., 8-10 hr) can be screened with 100% completeness from a single location and in a single night (near-IR). More luminous BDs require continuous monitoring for longer duration, e.g., from space or from a longitude-distributed network (one test scheduling achieved three telescopes, 13.5 contiguous hours). Using a simulated survey of the 21 closest known BDs (within 7 pc) we find that the probability of detecting at least one transiting habitable planet is between 4.5 +5.6 -1.4 % and 56 +31 -13 %, depending on our assumptions. We calculate that BDs within 5-10 pc are characterizable for potential biosignatures with a 6.5 m space telescope using ∼1% of a five-year mission's lifetime spread over a contiguous segment only one-fifth to one-tenth of this duration.

Comparative Climatology of Terrestrial Planets

Science.gov (United States)

Mackwell, Stephen J.; Simon-Miller, Amy A.; Harder, Jerald W.; Bullock, Mark A.

Public awareness of climate change on Earth is currently very high, promoting significant interest in atmospheric processes. We are fortunate to live in an era where it is possible to study the climates of many planets, including our own, using spacecraft and groundbased observations as well as advanced computational power that allows detailed modeling. Planetary atmospheric dynamics and structure are all governed by the same basic physics. Thus differences in the input variables (such as composition, internal structure, and solar radiation) among the known planets provide a broad suite of natural laboratory settings for gaining new understanding of these physical processes and their outcomes. Diverse planetary settings provide insightful comparisons to atmospheric processes and feedbacks on Earth, allowing a greater understanding of the driving forces and external influences on our own planetary climate. They also inform us in our search for habitable environments on planets orbiting distant stars, a topic that was a focus of Exoplanets, the preceding book in the University of Arizona Press Space Sciences Series. Quite naturally, and perhaps inevitably, our fascination with climate is largely driven toward investigating the interplay between the early development of life and the presence of a suitable planetary climate. Our understanding of how habitable planets come to be begins with the worlds closest to home. Venus, Earth, and Mars differ only modestly in their mass and distance from the Sun, yet their current climates could scarcely be more divergent. Our purpose for this book is to set forth the foundations for this emerging science and to bring to the forefront our current understanding of atmospheric formation and climate evolution. Although there is significant comparison to be made to atmospheric processes on nonterrestrial planets in our solar system — the gas and ice giants — here we focus on the terrestrial planets, leaving even broader comparisons

Basics of SCI Rehabilitation

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Full Text Available ... Diane M. Rowles, MS, NP How Family Life Changes After Spinal Cord Injury Nancy Rosenberg, PsyD Understanding SCI Rehabilitation Donald Peck Leslie, MD Adjusting to Social Life in a Wheelchair Lisa Rosen, MS Spasticity, ...

Basics of SCI Rehabilitation

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Full Text Available menu Understanding Spinal Cord Injury What is a Spinal Cord Injury Levels of Injury and What They Mean Animated Spinal Cord Injury Chart Spinal Cord Injury Facts and Figures Care and Treatment After SCI Spinal ...

Basics of SCI Rehabilitation

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Full Text Available ... RN Pediatric Injuries Pediatric Spinal Cord Injury 101 Lawrence Vogel, MD The Basics of Pediatric SCI Rehabilitation ... Rogers, PT Recreational Therapy after Spinal Cord Injury Jennifer Piatt, PhD Kristine Cichowski, MS Read Bio Founding ...

Basics of SCI Rehabilitation

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Full Text Available ... Adult Injuries Spinal Cord Injury 101 David Chen, MD Preventing Pressure Sores Mary Zeigler, MS Transition from ... Rosenberg, PsyD Understanding SCI Rehabilitation Donald Peck Leslie, MD Adjusting to Social Life in a Wheelchair Lisa ...

Magnetic Fields of Extrasolar Planets: Planetary Interiors and Habitability

Science.gov (United States)

Lazio, T. Joseph

2018-06-01

Ground-based observations showed that Jupiter's radio emission is linked to its planetary-scale magnetic field, and subsequent spacecraft observations have shown that most planets, and some moons, have or had a global magnetic field. Generated by internal dynamos, magnetic fields are one of the few remote sensing means of constraining the properties of planetary interiors. For the Earth, its magnetic field has been speculated to be partially responsible for its habitability, and knowledge of an extrasolar planet's magnetic field may be necessary to assess its habitability. The radio emission from Jupiter and other solar system planets is produced by an electron cyclotron maser, and detections of extrasolar planetary electron cyclotron masers will enable measurements of extrasolar planetary magnetic fields. Based on experience from the solar system, such observations will almost certainly require space-based observations, but they will also be guided by on-going and near-future ground-based observations.This work has benefited from the discussion and participants of the W. M. Keck Institute of Space Studies "Planetary Magnetic Fields: Planetary Interiors and Habitability" and content within a white paper submitted to the National Academy of Science Committee on Exoplanet Science Strategy. Part of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.

K2-106, a system containing a metal-rich planet and a planet of lower density

Science.gov (United States)

Guenther, E. W.; Barragán, O.; Dai, F.; Gandolfi, D.; Hirano, T.; Fridlund, M.; Fossati, L.; Chau, A.; Helled, R.; Korth, J.; Prieto-Arranz, J.; Nespral, D.; Antoniciello, G.; Deeg, H.; Hjorth, M.; Grziwa, S.; Albrecht, S.; Hatzes, A. P.; Rauer, H.; Csizmadia, Sz.; Smith, A. M. S.; Cabrera, J.; Narita, N.; Arriagada, P.; Burt, J.; Butler, R. P.; Cochran, W. D.; Crane, J. D.; Eigmüller, Ph.; Erikson, A.; Johnson, J. A.; Kiilerich, A.; Kubyshkina, D.; Palle, E.; Persson, C. M.; Pätzold, M.; Sabotta, S.; Sato, B.; Shectman, St. A.; Teske, J. K.; Thompson, I. B.; Van Eylen, V.; Nowak, G.; Vanderburg, A.; Winn, J. N.; Wittenmyer, R. A.

2017-12-01

Aims: Planets in the mass range from 2 to 15 M⊕ are very diverse. Some of them have low densities, while others are very dense. By measuring the masses and radii, the mean densities, structure, and composition of the planets are constrained. These parameters also give us important information about their formation and evolution, and about possible processes for atmospheric loss. Methods: We determined the masses, radii, and mean densities for the two transiting planets orbiting K2-106. The inner planet has an ultra-short period of 0.57 days. The period of the outer planet is 13.3 days. Results: Although the two planets have similar masses, their densities are very different. For K2-106b we derive Mb=8.36-0.94+0.96 M⊕, Rb = 1.52 ± 0.16 R⊕, and a high density of 13.1-3.6+5.4 g cm-3. For K2-106c, we find Mc=5.8-3.0+3.3 M⊕, Rc=2.50-0.26+0.27 R⊕ and a relatively low density of 2.0-1.1+1.6 g cm-3. Conclusions: Since the system contains two planets of almost the same mass, but different distances from the host star, it is an excellent laboratory to study atmospheric escape. In agreement with the theory of atmospheric-loss processes, it is likely that the outer planet has a hydrogen-dominated atmosphere. The mass and radius of the inner planet is in agreement with theoretical models predicting an iron core containing 80-30+20% of its mass. Such a high metal content is surprising, particularly given that the star has an ordinary (solar) metal abundance. We discuss various possible formation scenarios for this unusual planet. The results are partly based on observations obtained at the European Southern Observatory at Paranal, Chile in program 098.C-0860(A). This paper includes data gathered with the 6.5 m Magellan Telescopes located at Las Campanas Observatory, Chile. The article is also partly based on observations with the TNG, NOT. This work has also made use of data from the European Space Agency (ESA) mission Gaia (http

Basics of SCI Rehabilitation

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Full Text Available ... Spinal Cord Injury 101 Lawrence Vogel, MD The Basics of Pediatric SCI Rehabilitation Sara Klaas, MSW Transitions for Children with Spinal Cord Injury Patricia Mucia, RN Family Life After Pediatric Spinal Injury Dawn Sheaffer, MSW Rehabilitation ...

Length of stay and medical stability for spinal cord-injured patients on admission to an inpatient rehabilitation hospital: a comparison between a model SCI trauma center and non-SCI trauma center.

Science.gov (United States)

Ploumis, A; Kolli, S; Patrick, M; Owens, M; Beris, A; Marino, R J

2011-03-01

Retrospective database review. To compare lengths of stay (LOS), pressure ulcers and readmissions to the acute care hospital of patients admitted to the inpatient rehabilitation facility (IRF) from a model spinal cord injury (SCI) trauma center or from a non-SCI acute hospital. Only sparse data exist comparing the status of patients admitted to IRF from a model SCI trauma center or from a non-SCI acute hospital. Acute care, IRF and total LOS were compared between patients transferred to IRF from the SCI center (n=78) and from non-SCI centers (n=131). The percentages of pressure ulcers on admission to IRF and transfer back to acute care were also compared. Patients admitted to IRF from the SCI trauma center (SCI TC) had significantly shorter (P=0.01) acute care LOS and total LOS compared with patients admitted from non-SCI TCs. By neurological category, acute-care LOS was less for all groups admitted from the SCI center, but statistically significant only for tetraplegia. There was no significant difference in the incidence of readmissions to acute care from IRF. More patients from non-SCI centers (34%) than SCI centers (12%) had pressure ulcers (PSCI TCs before transfer to IRF can significantly lower acute-care LOS or total LOS and incidence of pressure ulcers compared with non-SCI TCs. Patients admitted to IRF from SCI TCs are no more likely to be sent back to an acute hospital than those from non-SCI TCs.

On the feasibility of detecting extrasolar planets by reflected starlight using the Hubble Space Telescope

Science.gov (United States)

Brown, Robert A.; Burrows, Christopher J.

1990-01-01

The best metrology data extant are presently used to estimate the center and wing point-spread function of the HST, in order to ascertain the implications of an observational criterion according to which a faint source's discovery can occur only when the signal recorded near its image's location is sufficiently larger than would be expected in its absence. After defining the maximum star-planet flux ratio, a figure of merit Q, defined as the contrast ratio between a 'best case' planet and the scattered starlight background, is introduced and shown in the HST's case to be unfavorable for extrasolar planet detection.

A novel space ocular syndrome is driving technology advances on and off the planet

Science.gov (United States)

Donoviel, Dorit B.; Zimmer, Cheryl N.; Clayton, Richard

2017-05-01

Astronauts are experiencing ophthalmological changes including optic disc edema, globe flattening, choroidal folds, and significant hyperopic shifts. In a handful of cases in which it was measured, intracranial pressure as measured by lumbar punctures was elevated post-flight. The severity of symptoms is highly variable and the underlying etiology is unknown, but a spaceflight associated cephalad-fluid shift is thought to play a role. NASA requires portable, non-invasive, clinically-validated approaches to assessing the ocular and the cerebral physiological, anatomical, and functional changes. Multispectral Imaging (MSI) that enables instruments installed on satellites in space to observe Earth was applied in an ophthalmic medical device that is clinically being used on Earth and now being evaluated for use on humans in space. The Annidis RHA™ (Ottawa, Canada) uses narrow band light emitting diodes (LEDs) to create discrete slices of anatomical structures of the posterior pole of the eye. The LEDs cover a frequency range from 520 to 940 nm, which allow for specific visualization of the different features of the posterior segment of the eye including retina, choroid and optic nerve head. Interestingly, infrared illumination at 940 nm reflects from the posterior sclera, retro-illuminating the choroidal vasculature without the need for invasive contrast agents. Abnormalities in retinal, choroidal or cerebral venous drainage and/or arterial flow may contribute to the microgravity ocular syndrome (MOS) in astronauts; hence this space technology may prove to be invaluable for diagnosing not only the health of our planet but also of the humans living on it and above it.

Amphibian and reptile communities in eleven Sites of Community Importance (SCI: relations between SCI area, heterogeneity and richness

Directory of Open Access Journals (Sweden)

Luca Canova

2007-11-01

Full Text Available Seven species of amphibians and reptiles were observed in eleven Sites of Community Importance (SCI of the Lodi Province (NW Italy. Distribution and relative abundance of amphibians appeared more variable than reptiles. Some species of conservation concern as R. latastei were influenced by habitat physiognomy, i.e. the surface of wooded areas are important in predict presence and relative abundance of this species. SCI with wider surfaces and higher habitat heterogeneity included higher number of species. Species richness, here considered as a raw index of biodiversity value and community quality, was significantly related to SCI area and habitat heterogeneity; since this significant positive relation is confirmed both for amphibians and reptiles we suggest that, in planning of natural areas, priority must be retained for biotopes able to host the higher number of species.

ALMOST ALL OF KEPLER'S MULTIPLE-PLANET CANDIDATES ARE PLANETS

Energy Technology Data Exchange (ETDEWEB)

Lissauer, Jack J.; Rowe, Jason F.; Bryson, Stephen T.; Howell, Steve B.; Jenkins, Jon M.; Kinemuchi, Karen; Koch, David G. [NASA Ames Research Center, Moffett Field, CA 94035 (United States); Marcy, Geoffrey W. [Astronomy Department, University of California, Berkeley, CA 94720 (United States); Adams, Elisabeth; Fressin, Francois; Geary, John; Holman, Matthew J.; Ragozzine, Darin [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Buchhave, Lars A. [Niels Bohr Institute, University of Copenhagen, DK-2100, Copenhagen (Denmark); Ciardi, David R. [Exoplanet Science Institute/Caltech, Pasadena, CA 91125 (United States); Cochran, William D. [Department of Astronomy, University of Texas, Austin, TX 78712 (United States); Fabrycky, Daniel C. [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States); Ford, Eric B.; Morehead, Robert C. [University of Florida, 211 Bryant Space Science Center, Gainesville, FL 32611 (United States); Gilliland, Ronald L., E-mail: Jack.Lissauer@nasa.gov [Space Telescope Science Institute, Baltimore, MD 21218 (United States); and others

2012-05-10

We present a statistical analysis that demonstrates that the overwhelming majority of Kepler candidate multiple transiting systems (multis) indeed represent true, physically associated transiting planets. Binary stars provide the primary source of false positives among Kepler planet candidates, implying that false positives should be nearly randomly distributed among Kepler targets. In contrast, true transiting planets would appear clustered around a smaller number of Kepler targets if detectable planets tend to come in systems and/or if the orbital planes of planets encircling the same star are correlated. There are more than one hundred times as many Kepler planet candidates in multi-candidate systems as would be predicted from a random distribution of candidates, implying that the vast majority are true planets. Most of these multis are multiple-planet systems orbiting the Kepler target star, but there are likely cases where (1) the planetary system orbits a fainter star, and the planets are thus significantly larger than has been estimated, or (2) the planets orbit different stars within a binary/multiple star system. We use the low overall false-positive rate among Kepler multis, together with analysis of Kepler spacecraft and ground-based data, to validate the closely packed Kepler-33 planetary system, which orbits a star that has evolved somewhat off of the main sequence. Kepler-33 hosts five transiting planets, with periods ranging from 5.67 to 41 days.

Observsational Planet Formation

Science.gov (United States)

Dong, Ruobing; Zhu, Zhaohuan; Fung, Jeffrey

2017-06-01

Planets form in gaseous protoplanetary disks surrounding newborn stars. As such, the most direct way to learn how they form from observations, is to directly watch them forming in disks. In the past, this was very difficult due to a lack of observational capabilities; as such, planet formation was largely a subject of pure theoretical astrophysics. Now, thanks to a fleet of new instruments with unprecedented resolving power that have come online recently, we have just started to unveil features in resolve images of protoplanetary disks, such as gaps and spiral arms, that are most likely associated with embedded (unseen) planets. By comparing observations with theoretical models of planet-disk interactions, the masses and orbits of these still forming planets may be constrained. Such planets may help us to directly test various planet formation models. This marks the onset of a new field — observational planet formation. I will introduce the current status of this field.

White dwarf planets

Directory of Open Access Journals (Sweden)

Bonsor Amy

2013-04-01

Full Text Available The recognition that planets may survive the late stages of stellar evolution, and the prospects for finding them around White Dwarfs, are growing. We discuss two aspects governing planetary survival through stellar evolution to the White Dwarf stage. First we discuss the case of a single planet, and its survival under the effects of stellar mass loss, radius expansion, and tidal orbital decay as the star evolves along the Asymptotic Giant Branch. We show that, for stars initially of 1 − 5 M⊙, any planets within about 1 − 5 AU will be engulfed, this distance depending on the stellar and planet masses and the planet's eccentricity. Planets engulfed by the star's envelope are unlikely to survive. Hence, planets surviving the Asymptotic Giant Branch phase will probably be found beyond ∼ 2 AU for a 1  M⊙ progenitor and ∼ 10 AU for a 5 M⊙ progenitor. We then discuss the evolution of two-planet systems around evolving stars. As stars lose mass, planet–planet interactions become stronger, and many systems stable on the Main Sequence become destabilised following evolution of the primary. The outcome of such instabilities is typically the ejection of one planet, with the survivor being left on an eccentric orbit. These eccentric planets could in turn be responsible for feeding planetesimals into the neighbourhood of White Dwarfs, causing observed pollution and circumstellar discs.

Transiting Planets from Kepler, K2 & TESS

Science.gov (United States)

Lissauer, Jack

2018-01-01

NASA's Kepler spacecraft, launched in 2009, has been a resounding success. More than 4000 planet candidates have been identified using data from Kepler primary mission, which ended in 2013, and greater than 2000 of these candidates have been verified as bona fide exoplanets. After the loss of two reaction wheels ended the primary mission, the Kepler spacecraft was repurposed in 2014 to observe many fields on the sky for short periods. This new mission, dubbed K2, has led to the discovery of greater than 600 planet candidates, approximately 200 of which have been verified to date; most of these exoplanets are closer to us than the majority of exoplanets discovered by the primary Kepler mission. TESS, launching in 2018, will survey most of the sky for exoplanets, with emphasis on those orbiting nearby and/or bright host stars, making these planets especially well-suited for follow-up observations with other observatories to characterize atmospheric compositions and other properties. More than one-third of the planet candidates found by NASA's are associated with target stars that have more than one planet candidate, and such 'multis' account for the majority of candidates that have been verified as true planets. The large number of multis tells us that flat multiplanet systems like our Solar System are common. Virtually all of the candidate planetary systems are stable, as tested by numerical integrations that assume a physically motivated mass-radius relationship. Statistical studies performed on these candidate systems reveal a great deal about the architecture of planetary systems, including the typical spacing of orbits and flatness. The characteristics of several of the most interesting confirmed Kepler & K2 multi-planet systems will also be discussed.

How to Directly Image a Habitable Planet Around Alpha Centauri with a 30-45 cm Space Telescope

Science.gov (United States)

Belikov, Ruslan; Bendek, Eduardo; Thomas, Sandrine; Males, Jared

2015-01-01

Several mission concepts are being studied to directly image planets around nearby stars. It is commonly thought that directly imaging a potentially habitable exoplanet around a Sun-like star requires space telescopes with apertures of at least 1m. A notable exception to this is Alpha Centauri (A and B), which is an extreme outlier among FGKM stars in terms of apparent habitable zone size: the habitable zones are approximately 3x wider in apparent size than around any other FGKM star. This enables a approximately 30-45cm visible light space telescope equipped with a modern high performance coronagraph or star shade to resolve the habitable zone at high contrast and directly image any potentially habitable planet that may exist in the system. The raw contrast requirements for such an instrument can be relaxed to 1e-8 if the mission spends 2 years collecting tens of thousands of images on the same target, enabling a factor of 500-1000 speckle suppression in post processing using a new technique called Orbital Difference Imaging (ODI). The raw light leak from both stars is controllable with a special wave front control algorithm known as Multi-Star Wave front Control (MSWC), which independently suppresses diffraction and aberrations from both stars using independent modes on the deformable mirror. This paper will present an analysis of the challenges involved with direct imaging of Alpha Centauri with a small telescope and how the above technologies are used together to solve them. We also show an example of a small coronagraphic mission concepts to take advantage of this opportunity called "ACESat: Alpha Centauri Exoplanet Satellite" submitted to NASA's small Explorer (SMEX) program in December of 2014.

Opening Remarks: SciDAC 2007

Science.gov (United States)

Strayer, Michael

2007-09-01

Good morning. Welcome to Boston, the home of the Red Sox, Celtics and Bruins, baked beans, tea parties, Robert Parker, and SciDAC 2007. A year ago I stood before you to share the legacy of the first SciDAC program and identify the challenges that we must address on the road to petascale computing—a road E E Cummins described as `. . . never traveled, gladly beyond any experience.' Today, I want to explore the preparations for the rapidly approaching extreme scale (X-scale) generation. These preparations are the first step propelling us along the road of burgeoning scientific discovery enabled by the application of X- scale computing. We look to petascale computing and beyond to open up a world of discovery that cuts across scientific fields and leads us to a greater understanding of not only our world, but our universe. As part of the President's America Competitiveness Initiative, the ASCR Office has been preparing a ten year vision for computing. As part of this planning the LBNL together with ORNL and ANL hosted three town hall meetings on Simulation and Modeling at the Exascale for Energy, Ecological Sustainability and Global Security (E3). The proposed E3 initiative is organized around four programmatic themes: Engaging our top scientists, engineers, computer scientists and applied mathematicians; investing in pioneering large-scale science; developing scalable analysis algorithms, and storage architectures to accelerate discovery; and accelerating the build-out and future development of the DOE open computing facilities. It is clear that we have only just started down the path to extreme scale computing. Plan to attend Thursday's session on the out-briefing and discussion of these meetings. The road to the petascale has been at best rocky. In FY07, the continuing resolution provided 12% less money for Advanced Scientific Computing than either the President, the Senate, or the House. As a consequence, many of you had to absorb a no cost extension for your

THE FIRST PLANETS: THE CRITICAL METALLICITY FOR PLANET FORMATION

International Nuclear Information System (INIS)

Johnson, Jarrett L.; Li Hui

2012-01-01

A rapidly growing body of observational results suggests that planet formation takes place preferentially at high metallicity. In the core accretion model of planet formation this is expected because heavy elements are needed to form the dust grains which settle into the midplane of the protoplanetary disk and coagulate to form the planetesimals from which planetary cores are assembled. As well, there is observational evidence that the lifetimes of circumstellar disks are shorter at lower metallicities, likely due to greater susceptibility to photoevaporation. Here we estimate the minimum metallicity for planet formation, by comparing the timescale for dust grain growth and settling to that for disk photoevaporation. For a wide range of circumstellar disk models and dust grain properties, we find that the critical metallicity above which planets can form is a function of the distance r at which the planet orbits its host star. With the iron abundance relative to that of the Sun [Fe/H] as a proxy for the metallicity, we estimate a lower limit for the critical abundance for planet formation of [Fe/H] crit ≅ –1.5 + log (r/1 AU), where an astronomical unit (AU) is the distance between the Earth and the Sun. This prediction is in agreement with the available observational data, and carries implications for the properties of the first planets and for the emergence of life in the early universe. In particular, it implies that the first Earth-like planets likely formed from circumstellar disks with metallicities Z ∼> 0.1 Z ☉ . If planets are found to orbit stars with metallicities below the critical metallicity, this may be a strong challenge to the core accretion model.

The Scattering Outcomes of Kepler Circumbinary Planets: Planet Mass Ratio

Energy Technology Data Exchange (ETDEWEB)

Gong, Yan-Xiang; Ji, Jianghui, E-mail: yxgong@pmo.ac.cn, E-mail: jijh@pmo.ac.cn [CAS Key Laboratory of Planetary Sciences, Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008 (China)

2017-11-01

Recent studies reveal that the free eccentricities of Kepler-34b and Kepler-413b are much larger than their forced eccentricities, implying that scattering events may take place in their formation. The observed orbital configuration of Kepler-34b cannot be well reproduced in disk-driven migration models, whereas a two-planet scattering scenario can play a significant role of shaping the planetary configuration. These studies indicate that circumbinary planets discovered by Kepler may have experienced scattering process. In this work, we extensively investigate the scattering outcomes of circumbinary planets focusing on the effects of planet mass ratio . We find that the planetary mass ratio and the the initial relative locations of planets act as two important parameters that affect the eccentricity distribution of the surviving planets. As an application of our model, we discuss the observed orbital configurations of Kepler-34b and Kepler-413b. We first adopt the results from the disk-driven models as the initial conditions, then simulate the scattering process that occurs in the late evolution stage of circumbinary planets. We show that the present orbital configurations of Kepler-34b and Kepler-413b can be well reproduced when considering a two unequal-mass planet ejection model. Our work further suggests that some of the currently discovered circumbinary single-planet systems may be survivors of original multiple-planet systems. The disk-driven migration and scattering events occurring in the late stage both play an irreplaceable role in sculpting the final systems.

Simulated JWST/NIRISS Transit Spectroscopy of Anticipated TESS Planets Compared to Select Discoveries from Space-Based and Ground-Based Surveys

Science.gov (United States)

Louie, Dana; Deming, Drake; Albert, Loic; Bouma, Luke; Bean, Jacob; Lopez-Morales, Mercedes

2018-01-01

The Transiting Exoplanet Survey Satellite (TESS) will embark in 2018 on a 2-year wide-field survey mission of most of the celestial sky, discovering over a thousand super-Earth and sub-Neptune-sized exoplanets potentially suitable for follow-up observations using the James Webb Space Telescope (JWST). Bouma et al. (2017) and Sullivan et al. (2015) used Monte Carlo simulations to predict the properties of the planetary systems that TESS is likely to detect, basing their simulations upon Kepler-derived planet occurrence rates and photometric performance models for the TESS cameras. We employed a JWST Near InfraRed Imager and Slitless Spectrograph (NIRISS) simulation tool to estimate the signal-to-noise (S/N) that JWST/NIRISS will attain in transmission spectroscopy of these anticipated TESS discoveries, and we then compared the S/N for anticipated TESS discoveries to our estimates of S/N for 18 known exoplanets. We analyzed the sensitivity of our results to planetary composition, cloud cover, and presence of an observational noise floor. We find that only a few anticipated TESS discoveries in the terrestrial planet regime will result in better JWST/NIRISS S/N than currently known exoplanets, such as the TRAPPIST-1 planets, GJ1132b, or LHS1140b. However, we emphasize that this outcome is based upon Kepler-derived occurrence rates, and that co-planar compact systems (e.g. TRAPPIST-1) were not included in predicting the anticipated TESS planet yield. Furthermore, our results show that several hundred anticipated TESS discoveries in the super-Earth and sub-Neptune regime will produce S/N higher than currently known exoplanets such as K2-3b or K2-3c. We apply our results to estimate the scope of a JWST follow-up observation program devoted to mapping the transition region between high molecular weight and primordial planetary atmospheres.

Transiting exoplanets from the CoRoT space mission. IV. CoRoT-Exo-4b: a transiting planet in a 9.2 day synchronous orbit

Science.gov (United States)

Aigrain, S.; Collier Cameron, A.; Ollivier, M.; Pont, F.; Jorda, L.; Almenara, J. M.; Alonso, R.; Barge, P.; Bordé, P.; Bouchy, F.; Deeg, H.; de La Reza, R.; Deleuil, M.; Dvorak, R.; Erikson, A.; Fridlund, M.; Gondoin, P.; Gillon, M.; Guillot, T.; Hatzes, A.; Lammer, H.; Lanza, A. F.; Léger, A.; Llebaria, A.; Magain, P.; Mazeh, T.; Moutou, C.; Paetzold, M.; Pinte, C.; Queloz, D.; Rauer, H.; Rouan, D.; Schneider, J.; Wuchter, G.; Zucker, S.

2008-09-01

CoRoT, the first space-based transit search, provides ultra-high-precision light curves with continuous time-sampling over periods of up to 5 months. This allows the detection of transiting planets with relatively long periods, and the simultaneous study of the host star's photometric variability. In this Letter, we report the discovery of the transiting giant planet CoRoT-Exo-4b and use the CoRoT light curve to perform a detailed analysis of the transit and determine the stellar rotation period. The CoRoT light curve was pre-processed to remove outliers and correct for orbital residuals and artefacts due to hot pixels on the detector. After removing stellar variability about each transit, the transit light curve was analysed to determine the transit parameters. A discrete autocorrelation function method was used to derive the rotation period of the star from the out-of-transit light curve. We determine the periods of the planetary orbit and star's rotation of 9.20205 ± 0.00037 and 8.87 ± 1.12 days respectively, which is consistent with this being a synchronised system. We also derive the inclination, i = 90.00_-0.085+0.000 in degrees, the ratio of the orbital distance to the stellar radius, a/Rs = 17.36-0.25+0.05, and the planet-to-star radius ratio R_p/R_s=0.1047-0.0022+0.0041. We discuss briefly the coincidence between the orbital period of the planet and the stellar rotation period and its possible implications for the system's migration and star-planet interaction history. The CoRoT space mission, launched on December 27th 2006, has been developed and is operated by CNES, with the contribution of Austria, Belgium, Brazil, ESA, Germany, and Spain. The first CoRoT data will be available to the public in February 2009 from the CoRoT archive: http://idoc-corot.ias.u-psud.fr/ Figures 1, 4 and 5 are only available in electronic form at http://www.aanda.org

Extrasolar planets: constraints for planet formation models.

Science.gov (United States)

Santos, Nuno C; Benz, Willy; Mayor, Michel

2005-10-14

Since 1995, more than 150 extrasolar planets have been discovered, most of them in orbits quite different from those of the giant planets in our own solar system. The number of discovered extrasolar planets demonstrates that planetary systems are common but also that they may possess a large variety of properties. As the number of detections grows, statistical studies of the properties of exoplanets and their host stars can be conducted to unravel some of the key physical and chemical processes leading to the formation of planetary systems.

From Disks to Planets: The Making of Planets and Their Early Atmospheres. An Introduction

Science.gov (United States)

Lammer, Helmut; Blanc, Michel

2018-03-01

This paper is an introduction to volume 56 of the Space Science Series of ISSI, "From disks to planets—the making of planets and their proto-atmospheres", a key subject in our quest for the origins and evolutionary paths of planets, and for the causes of their diversity. Indeed, as exoplanet discoveries progressively accumulated and their characterization made spectacular progress, it became evident that the diversity of observed exoplanets can in no way be reduced to the two classes of planets that we are used to identify in the solar system, namely terrestrial planets and gas or ice giants: the exoplanet reality is just much broader. This fact is no doubt the result of the exceptional diversity of the evolutionary paths linking planetary systems as a whole as well as individual exoplanets and their proto-atmospheres to their parent circumstellar disks: this diversity and its causes are exactly what this paper explores. For each of the main phases of the formation and evolution of planetary systems and of individual planets, we summarize what we believe we understand and what are the important open questions needing further in-depth examination, and offer some suggestions on ways towards solutions. We start with the formation mechanisms of circumstellar disks, with their gas and disk components in which chemical composition plays a very important role in planet formation. We summarize how dust accretion within the disk generates planet cores, while gas accretion on these cores can lead to the diversity of their fluid envelopes. The temporal evolution of the parent disk itself, and its final dissipation, put strong constraints on how and how far planetary formation can proceed. The radiation output of the central star also plays an important role in this whole story. This early phase of planet evolution, from disk formation to dissipation, is characterized by a co-evolution of the disk and its daughter planets. During this co-evolution, planets and their

GeoSciML and EarthResourceML Update, 2012

Science.gov (United States)

Richard, S. M.; Commissionthe Management; Application Inte, I.

2012-12-01

CGI Interoperability Working Group activities during 2012 include deployment of services using the GeoSciML-Portrayal schema, addition of new vocabularies to support properties added in version 3.0, improvements to server software for deploying services, introduction of EarthResourceML v.2 for mineral resources, and collaboration with the IUSS on a markup language for soils information. GeoSciML and EarthResourceML have been used as the basis for the INSPIRE Geology and Mineral Resources specifications respectively. GeoSciML-Portrayal is an OGC GML simple-feature application schema for presentation of geologic map unit, contact, and shear displacement structure (fault and ductile shear zone) descriptions in web map services. Use of standard vocabularies for geologic age and lithology enables map services using shared legends to achieve visual harmonization of maps provided by different services. New vocabularies have been added to the collection of CGI vocabularies provided to support interoperable GeoSciML services, and can be accessed through http://resource.geosciml.org. Concept URIs can be dereferenced to obtain SKOS rdf or html representations using the SISSVoc vocabulary service. New releases of the FOSS GeoServer application greatly improve support for complex XML feature schemas like GeoSciML, and the ArcGIS for INSPIRE extension implements similar complex feature support for ArcGIS Server. These improved server implementations greatly facilitate deploying GeoSciML services. EarthResourceML v2 adds features for information related to mining activities. SoilML provides an interchange format for soil material, soil profile, and terrain information. Work is underway to add GeoSciML to the portfolio of Open Geospatial Consortium (OGC) specifications.

ComSciCon: The Communicating Science Workshop for Graduate Students

Science.gov (United States)

Sanders, Nathan; Drout, Maria; Kohler, Susanna; Cook, Ben; ComSciCon Leadership Team

2018-01-01

ComSciCon (comscicon.com) is a national workshop series organized by graduate students, for graduate students, focused on leadership and training in science communication. Our goal is to empower young scientists to become leaders in their field, propagating appreciation and understanding of research results to broad and diverse audiences. ComSciCon attendees meet and interact with professional communicators, build lasting networks with graduate students in all fields of science and engineering from around the country, and write and publish original works. ComSciCon consists of both a flagship national conference series run annually for future leaders in science communication, and a series of regional and specialized workshops organized by ComSciCon alumni nationwide. We routinely receive over 1000 applications for 50 spots in our national workshop. Since its founding in 2012, over 300 STEM graduate students have participated in the national workshop, and 23 local spin-off workshops have been organized in 10 different locations throughout the country. This year, ComSciCon is working to grow as a self-sustaining organization by launching as an independent 501(c)(3) non-profit. In this poster we will discuss the ComSciCon program and methods, our results to date, potential future collaborations between ComSciCon and AAS, and how you can become involved.

DOI in scientific journals of SciELO portal

Directory of Open Access Journals (Sweden)

Sandra Gisela Martín

2013-10-01

Full Text Available The research provides a description of the SciELO journals portal and the DOI identifier through its range, year of creation, history, management, policy, structure, ISBN-A and reference sources. It provides information on the implementation of the DOI in citations styles APA and Vancouver, and standards ISO 690-2010 and ABNT6023-2002. The work aimed to explore the degree of implementation of the DOI in scientific journals in SciELO, identify where DOI display, knowing the amount of publishers as DOI prefix, determine the number of journals titles including the ISSN suffix code and identify the degree of implementation of the DOI in the styles and standards of citations available in SciELO. Descriptive methodology was applied where data were collected through direct observation of the websites of the 898 current journals available between the months of December 2012 and January 2013 in SciELO portal. It concludes that less than 50% of the countries in SciELO are currently using the DOI in its publications, primarily displayed code in HTML files, only 30 of the 929 publishers implemented it and most include the ISSN identifier within the suffix. While using the DOI in all citations of the articles, not does so strict as the provisions of the rules and styles.

Measuring Precise Radii of Giants Orbiting Giants to Distinguish Between Planet Evolution Models

Science.gov (United States)

Grunblatt, Samuel; Huber, Daniel; Lopez, Eric; Gaidos, Eric; Livingston, John

2017-10-01

Despite more than twenty years since the initial discovery of highly irradiated gas giant planets, the mechanism for planet inflation remains unknown. However, proposed planet inflation mechanisms can now be separated into two general classes: those which allow for post-main sequence planet inflation by direct irradiation from the host star, and those which only allow for slowed cooling of the planet over its lifetime. The recent discovery of two inflated warm Jupiters orbiting red giant stars with the NASA K2 Mission allows distinction between these two classes, but uncertainty in the planet radius blurs this distinction. Observing transits of these planets with the Spitzer Space Telescope would reduce stellar variability and thus planet radius uncertainties by approximately 50% relative to K2, allowing distinction between the two planet inflation model classes at a 3-sigma level. We propose to observe one transit of both known warm Jupiters orbiting red giant stars, K2-97b and EPIC228754001.01, to distinguish between planet model inflation classes and measure the planetary heating efficiency to 3-sigma precision. These systems are benchmarks for the upcoming NASA TESS Mission, which is predicted to discover an order of magnitude more red giant planet systems after launching next year.

An introduction to planets ours and others : from Earth to exoplanets

CERN Document Server

Encrenaz, Thérèse

2014-01-01

What is a planet? The answer seems obvious, but nonetheless the definition of a planet has continuously evolved over the centuries, and their number has changed following successive discoveries. The decision endorsed by the International Astronomical Union to remove Pluto from the list of planets in 2006 well illustrates the difficulty associated with their definition. The recent discovery of hundreds of exoplanets around nearby stars of our Galaxy opens a new and spectacular dimension to astrophysics. We presently know very little about the physical nature of exoplanets. In contrast, our knowledge of Solar System planets has made huge progress over the past decades, thanks, especially, to space planetary exploration. The purpose of this book is first to characterize what planets are, in their global properties and in their diversity. Then, this knowledge is used to try to imagine the physical nature of exoplanets, starting from the few parameters we know about them. Throughout this book, as we explore the su...

HABITABLE PLANETS ECLIPSING BROWN DWARFS: STRATEGIES FOR DETECTION AND CHARACTERIZATION

Energy Technology Data Exchange (ETDEWEB)

Belu, Adrian R.; Selsis, Franck; Raymond, Sean N.; Bolmont, Emeline [Universite de Bordeaux, LAB, UMR 5804, F-33270, Floirac (France); Palle, Enric [Instituto de Astrofisica de Canarias, E-38205 La Laguna (Spain); Street, Rachel [Las Cumbres Observatory Global Telescope Network, 6740 Cortona Drive, Suite 102, Goleta, CA 93117 (United States); Sahu, D. K.; Anupama, G. C. [Indian Institute of Astrophysics, Koramangala, Bangalore 560034 (India); Von Braun, Kaspar [NASA Exoplanet Science Institute, California Institute of Technology, MC 100-22, Pasadena, CA 91125 (United States); Figueira, Pedro [Centro de Astrofisica, Universidade do Porto, Rua das Estrelas, 4150-762 Porto (Portugal); Ribas, Ignasi, E-mail: belu@obs.u-bordeaux1.fr [Institut de Ciencies de l' Espai (CSIC-IEEC), Campus UAB, Facultat de Ciencies, Torre C5, parell, 2a pl., E-08193 Bellaterra (Spain)

2013-05-10

Given the very close proximity of their habitable zones, brown dwarfs (BDs) represent high-value targets in the search for nearby transiting habitable planets that may be suitable for follow-up occultation spectroscopy. In this paper, we develop search strategies to find habitable planets transiting BDs depending on their maximum habitable orbital period (P{sub HZ{sub out}}). Habitable planets with P{sub HZ{sub out}} shorter than the useful duration of a night (e.g., 8-10 hr) can be screened with 100% completeness from a single location and in a single night (near-IR). More luminous BDs require continuous monitoring for longer duration, e.g., from space or from a longitude-distributed network (one test scheduling achieved three telescopes, 13.5 contiguous hours). Using a simulated survey of the 21 closest known BDs (within 7 pc) we find that the probability of detecting at least one transiting habitable planet is between 4.5{sup +5.6}{sub -1.4}% and 56{sup +31}{sub -13}%, depending on our assumptions. We calculate that BDs within 5-10 pc are characterizable for potential biosignatures with a 6.5 m space telescope using {approx}1% of a five-year mission's lifetime spread over a contiguous segment only one-fifth to one-tenth of this duration.

DECIPHERING THERMAL PHASE CURVES OF DRY, TIDALLY LOCKED TERRESTRIAL PLANETS

Energy Technology Data Exchange (ETDEWEB)

Koll, Daniel D. B.; Abbot, Dorian S., E-mail: dkoll@uchicago.edu [Department of the Geophysical Sciences, University of Chicago, Chicago, IL 60637 (United States)

2015-03-20

Next-generation space telescopes will allow us to characterize terrestrial exoplanets. To do so effectively it will be crucial to make use of all available data. We investigate which atmospheric properties can, and cannot, be inferred from the broadband thermal phase curve of a dry and tidally locked terrestrial planet. First, we use dimensional analysis to show that phase curves are controlled by six nondimensional parameters. Second, we use an idealized general circulation model to explore the relative sensitivity of phase curves to these parameters. We find that the feature of phase curves most sensitive to atmospheric parameters is the peak-to-trough amplitude. Moreover, except for hot and rapidly rotating planets, the phase amplitude is primarily sensitive to only two nondimensional parameters: (1) the ratio of dynamical to radiative timescales and (2) the longwave optical depth at the surface. As an application of this technique, we show how phase curve measurements can be combined with transit or emission spectroscopy to yield a new constraint for the surface pressure and atmospheric mass of terrestrial planets. We estimate that a single broadband phase curve, measured over half an orbit with the James Webb Space Telescope, could meaningfully constrain the atmospheric mass of a nearby super-Earth. Such constraints will be important for studying the atmospheric evolution of terrestrial exoplanets as well as characterizing the surface conditions on potentially habitable planets.

Sex and Fertility After SCI

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Full Text Available ... Living with SCI Personal Experiences by Topic Resources Peer ... Injuries Spinal Cord Injury 101 David Chen, MD Preventing Pressure Sores Mary Zeigler, MS Transition from Hospital to ...

Overview of the Spinal Cord Injury--Quality of Life (SCI-QOL) measurement system.

Science.gov (United States)

Tulsky, David S; Kisala, Pamela A; Victorson, David; Tate, Denise G; Heinemann, Allen W; Charlifue, Susan; Kirshblum, Steve C; Fyffe, Denise; Gershon, Richard; Spungen, Ann M; Bombardier, Charles H; Dyson-Hudson, Trevor A; Amtmann, Dagmar; Kalpakjian, Claire Z; Choi, Seung W; Jette, Alan M; Forchheimer, Martin; Cella, David

2015-05-01

The Spinal Cord Injury--Quality of Life (SCI-QOL) measurement system was developed to address the shortage of relevant and psychometrically sound patient reported outcome (PRO) measures available for clinical care and research in spinal cord injury (SCI) rehabilitation. Using a computer adaptive testing (CAT) approach, the SCI-QOL builds on the Patient Reported Outcomes Measurement Information System (PROMIS) and the Quality of Life in Neurological Disorders (Neuro-QOL) initiative. This initial manuscript introduces the background and development of the SCI-QOL measurement system. Greater detail is presented in the additional manuscripts of this special issue. Classical and contemporary test development methodologies were employed. Qualitative input was obtained from individuals with SCI and clinicians through interviews, focus groups, and cognitive debriefing. Item pools were field tested in a multi-site sample (n=877) and calibrated using item response theory methods. Initial reliability and validity testing was performed in a new sample of individuals with traumatic SCI (n=245). Five Model SCI System centers and one Department of Veterans Affairs Medical Center across the United States. Adults with traumatic SCI. n/a n/a The SCI-QOL consists of 19 item banks, including the SCI-Functional Index banks, and 3 fixed-length scales measuring physical, emotional, and social aspects of health-related QOL (HRQOL). The SCI-QOL measurement system consists of psychometrically sound measures for individuals with SCI. The manuscripts in this special issue provide evidence of the reliability and initial validity of this measurement system. The SCI-QOL also links to other measures designed for a general medical population.

Detecting tree-like multicellular life on extrasolar planets.

Science.gov (United States)

Doughty, Christopher E; Wolf, Adam

2010-11-01

Over the next two decades, NASA and ESA are planning a series of space-based observatories to find Earth-like planets and determine whether life exists on these planets. Previous studies have assessed the likelihood of detecting life through signs of biogenic gases in the atmosphere or a red edge. Biogenic gases and the red edge could be signs of either single-celled or multicellular life. In this study, we propose a technique with which to determine whether tree-like multicellular life exists on extrasolar planets. For multicellular photosynthetic organisms on Earth, competition for light and the need to transport water and nutrients has led to a tree-like body plan characterized by hierarchical branching networks. This design results in a distinct bidirectional reflectance distribution function (BRDF) that causes differing reflectance at different sun/view geometries. BRDF arises from the changing visibility of the shadows cast by objects, and the presence of tree-like structures is clearly distinguishable from flat ground with the same reflectance spectrum. We examined whether the BRDF could detect the existence of tree-like structures on an extrasolar planet by using changes in planetary albedo as a planet orbits its star. We used a semi-empirical BRDF model to simulate vegetation reflectance at different planetary phase angles and both simulated and real cloud cover to calculate disk and rotation-averaged planetary albedo for a vegetated and non-vegetated planet with abundant liquid water. We found that even if the entire planetary albedo were rendered to a single pixel, the rate of increase of albedo as a planet approaches full illumination would be comparatively greater on a vegetated planet than on a non-vegetated planet. Depending on how accurately planetary cloud cover can be resolved and the capabilities of the coronagraph to resolve exoplanets, this technique could theoretically detect tree-like multicellular life on exoplanets in 50 stellar systems.

Terrestrial planet formation.

Science.gov (United States)

Righter, K; O'Brien, D P

2011-11-29

Advances in our understanding of terrestrial planet formation have come from a multidisciplinary approach. Studies of the ages and compositions of primitive meteorites with compositions similar to the Sun have helped to constrain the nature of the building blocks of planets. This information helps to guide numerical models for the three stages of planet formation from dust to planetesimals (~10(6) y), followed by planetesimals to embryos (lunar to Mars-sized objects; few 10(6) y), and finally embryos to planets (10(7)-10(8) y). Defining the role of turbulence in the early nebula is a key to understanding the growth of solids larger than meter size. The initiation of runaway growth of embryos from planetesimals ultimately leads to the growth of large terrestrial planets via large impacts. Dynamical models can produce inner Solar System configurations that closely resemble our Solar System, especially when the orbital effects of large planets (Jupiter and Saturn) and damping mechanisms, such as gas drag, are included. Experimental studies of terrestrial planet interiors provide additional constraints on the conditions of differentiation and, therefore, origin. A more complete understanding of terrestrial planet formation might be possible via a combination of chemical and physical modeling, as well as obtaining samples and new geophysical data from other planets (Venus, Mars, or Mercury) and asteroids.

Sci-Hub provides access to nearly all scholarly literature.

Science.gov (United States)

Himmelstein, Daniel S; Romero, Ariel Rodriguez; Levernier, Jacob G; Munro, Thomas Anthony; McLaughlin, Stephen Reid; Greshake Tzovaras, Bastian; Greene, Casey S

2018-03-01

The website Sci-Hub enables users to download PDF versions of scholarly articles, including many articles that are paywalled at their journal's site. Sci-Hub has grown rapidly since its creation in 2011, but the extent of its coverage has been unclear. Here we report that, as of March 2017, Sci-Hub's database contains 68.9% of the 81.6 million scholarly articles registered with Crossref and 85.1% of articles published in toll access journals. We find that coverage varies by discipline and publisher, and that Sci-Hub preferentially covers popular, paywalled content. For toll access articles, we find that Sci-Hub provides greater coverage than the University of Pennsylvania, a major research university in the United States. Green open access to toll access articles via licit services, on the other hand, remains quite limited. Our interactive browser at https://greenelab.github.io/scihub allows users to explore these findings in more detail. For the first time, nearly all scholarly literature is available gratis to anyone with an Internet connection, suggesting the toll access business model may become unsustainable. © 2018, Himmelstein et al.

Extrasolar Planets: Towards Comparative Planetology beyond the Solar System

Science.gov (United States)

Khan, A. H.

2012-09-01

Today Scenario planet logy is a very important concept because now days the scientific research finding new and new planets and our work's range becoming too long. In the previous study shows about 10-12 years the research of planet logy now has changed . Few years ago we was talking about Sun planet, Earth planet , Moon ,Mars Jupiter & Venus etc. included but now the time has totally changed the recent studies showed that mono lakes California find the arsenic food use by micro organism that show that our study is very tiny as compare to planet long areas .We have very well known that arsenic is the toxic agent's and the toxic agent's present in the lakes and micro organism developing and life going on it's a unbelievable point for us but nature always play a magical games. In few years ago Aliens was the story no one believe the Aliens origin but now the aliens showed catch by our space craft and shuttle and every one believe that Aliens origin but at the moment's I would like to mention one point's that we have too more work required because our planet logy has a vast field. Most of the time our scientific mission shows that this planet found liquid oxygen ,this planet found hydrogen .I would like to clear that point's that all planet logy depend in to the chemical and these chemical gave the indication of the life but we are not abele to developed the adaptation according to the micro organism . Planet logy compare before study shows that Sun it's a combination of the various gases combination surrounded in a round form and now the central Sun Planets ,moons ,comets and asteroids In other word we can say that Or Sun has a wide range of the physical and Chemical properties in the after the development we can say that all chemical and physical property engaged with a certain environment and form a various contains like asteroids, moon, Comets etc. Few studies shows that other planet life affected to the out living planet .We can assure with the example the life

Sensitivity of the SCI-FI/AT in Individuals With Traumatic Spinal Cord Injury.

Science.gov (United States)

Keeney, Tamra; Slavin, Mary; Kisala, Pamela; Ni, Pengsheng; Heinemann, Allen W; Charlifue, Susan; Fyffe, Denise C; Marino, Ralph J; Morse, Leslie R; Worobey, Lynn A; Tate, Denise; Rosenblum, David; Zafonte, Ross; Tulsky, David; Jette, Alan M

2018-03-31

To examine the ability of the Spinal Cord Injury-Functional Index/Assistive Technology (SCI-FI/AT) measure to detect change in persons with spinal cord injury (SCI). Multisite longitudinal (12-mo follow-up) study. Nine SCI Model Systems programs. Adults (N=165) with SCI enrolled in the SCI Model Systems database. Not applicable. SCI-FI/AT computerized adaptive test (CAT) (Basic Mobility, Self-Care, Fine Motor Function, Wheelchair Mobility, and/or Ambulation domains) completed at discharge from rehabilitation and 12 months after SCI. For each domain, effect size estimates and 95% confidence intervals were calculated for subgroups with paraplegia and tetraplegia. The demographic characteristics of the sample were as follows: 46% (n=76) individuals with paraplegia, 76% (n=125) male participants, 57% (n=94) used a manual wheelchair, 38% (n=63) used a power wheelchair, 30% (n=50) were ambulatory. For individuals with paraplegia, the Basic Mobility, Self-Care, and Ambulation domains of the SCI-FI/AT detected a significantly large amount of change; in contrast, the Fine Motor Function and Wheelchair Mobility domains detected only a small amount of change. For those with tetraplegia, the Basic Mobility, Fine Motor Function, and Self-Care domains detected a small amount of change whereas the Ambulation item domain detected a medium amount of change. The Wheelchair Mobility domain for people with tetraplegia was the only SCI-FI/AT domain that did not detect significant change. SCI-FI/AT CAT item banks detected an increase in function from discharge to 12 months after SCI. The effect size estimates for the SCI-FI/AT CAT vary by domain and level of lesion. Findings support the use of the SCI-FI/AT CAT in the population with SCI and highlight the importance of multidimensional functional measures. Copyright © 2018 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Methodology for the development and calibration of the SCI-QOL item banks.

Science.gov (United States)

Tulsky, David S; Kisala, Pamela A; Victorson, David; Choi, Seung W; Gershon, Richard; Heinemann, Allen W; Cella, David

2015-05-01

To develop a comprehensive, psychometrically sound, and conceptually grounded patient reported outcomes (PRO) measurement system for individuals with spinal cord injury (SCI). Individual interviews (n=44) and focus groups (n=65 individuals with SCI and n=42 SCI clinicians) were used to select key domains for inclusion and to develop PRO items. Verbatim items from other cutting-edge measurement systems (i.e. PROMIS, Neuro-QOL) were included to facilitate linkage and cross-population comparison. Items were field tested in a large sample of individuals with traumatic SCI (n=877). Dimensionality was assessed with confirmatory factor analysis. Local item dependence and differential item functioning were assessed, and items were calibrated using the item response theory (IRT) graded response model. Finally, computer adaptive tests (CATs) and short forms were administered in a new sample (n=245) to assess test-retest reliability and stability. A calibration sample of 877 individuals with traumatic SCI across five SCI Model Systems sites and one Department of Veterans Affairs medical center completed SCI-QOL items in interview format. We developed 14 unidimensional calibrated item banks and 3 calibrated scales across physical, emotional, and social health domains. When combined with the five Spinal Cord Injury--Functional Index physical function banks, the final SCI-QOL system consists of 22 IRT-calibrated item banks/scales. Item banks may be administered as CATs or short forms. Scales may be administered in a fixed-length format only. The SCI-QOL measurement system provides SCI researchers and clinicians with a comprehensive, relevant and psychometrically robust system for measurement of physical-medical, physical-functional, emotional, and social outcomes. All SCI-QOL instruments are freely available on Assessment CenterSM.

PLANET-PLANET SCATTERING IN PLANETESIMAL DISKS. II. PREDICTIONS FOR OUTER EXTRASOLAR PLANETARY SYSTEMS

International Nuclear Information System (INIS)

Raymond, Sean N.; Armitage, Philip J.; Gorelick, Noel

2010-01-01

We develop an idealized dynamical model to predict the typical properties of outer extrasolar planetary systems, at radii comparable to the Jupiter-to-Neptune region of the solar system. The model is based upon the hypothesis that dynamical evolution in outer planetary systems is controlled by a combination of planet-planet scattering and planetary interactions with an exterior disk of small bodies ('planetesimals'). Our results are based on 5000 long duration N-body simulations that follow the evolution of three planets from a few to 10 AU, together with a planetesimal disk containing 50 M + from 10 to 20 AU. For large planet masses (M ∼> M Sat ), the model recovers the observed eccentricity distribution of extrasolar planets. For lower-mass planets, the range of outcomes in models with disks is far greater than that which is seen in isolated planet-planet scattering. Common outcomes include strong scattering among massive planets, sudden jumps in eccentricity due to resonance crossings driven by divergent migration, and re-circularization of scattered low-mass planets in the outer disk. We present the distributions of the eccentricity and inclination that result, and discuss how they vary with planet mass and initial system architecture. In agreement with other studies, we find that the currently observed eccentricity distribution (derived primarily from planets at a ∼ -1 and periods in excess of 10 years will provide constraints on this regime. Finally, we present an analysis of the predicted separation of planets in two-planet systems, and of the population of planets in mean-motion resonances (MMRs). We show that, if there are systems with ∼ Jupiter-mass planets that avoid close encounters, the planetesimal disk acts as a damping mechanism and populates MMRs at a very high rate (50%-80%). In many cases, resonant chains (in particular the 4:2:1 Laplace resonance) are set up among all three planets. We expect such resonant chains to be common among massive

Planet Formation

Science.gov (United States)

Podolak, Morris

2018-04-01

Modern observational techniques are still not powerful enough to directly view planet formation, and so it is necessary to rely on theory. However, observations do give two important clues to the formation process. The first is that the most primitive form of material in interstellar space exists as a dilute gas. Some of this gas is unstable against gravitational collapse, and begins to contract. Because the angular momentum of the gas is not zero, it contracts along the spin axis, but remains extended in the plane perpendicular to that axis, so that a disk is formed. Viscous processes in the disk carry most of the mass into the center where a star eventually forms. In the process, almost as a by-product, a planetary system is formed as well. The second clue is the time required. Young stars are indeed observed to have gas disks, composed mostly of hydrogen and helium, surrounding them, and observations tell us that these disks dissipate after about 5 to 10 million years. If planets like Jupiter and Saturn, which are very rich in hydrogen and helium, are to form in such a disk, they must accrete their gas within 5 million years of the time of the formation of the disk. Any formation scenario one proposes must produce Jupiter in that time, although the terrestrial planets, which don't contain significant amounts of hydrogen and helium, could have taken longer to build. Modern estimates for the formation time of the Earth are of the order of 100 million years. To date there are two main candidate theories for producing Jupiter-like planets. The core accretion (CA) scenario supposes that any solid materials in the disk slowly coagulate into protoplanetary cores with progressively larger masses. If the core remains small enough it won't have a strong enough gravitational force to attract gas from the surrounding disk, and the result will be a terrestrial planet. If the core grows large enough (of the order of ten Earth masses), and the disk has not yet dissipated, then

Sex and Fertility After SCI

Medline Plus

Full Text Available ... How Peer Counseling Works Julie Gassaway, MS, RN Pediatric Injuries Pediatric Spinal Cord Injury 101 Lawrence Vogel, MD The Basics of Pediatric SCI Rehabilitation Sara Klaas, MSW Transitions for Children ...

Sex and Fertility After SCI

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Full Text Available ... Medical Experts People Living with SCI Personal Experiences by Topic Resources Peer ... Injuries Spinal Cord Injury 101 David Chen, MD Preventing Pressure Sores Mary Zeigler, MS Transition from Hospital to ...

Measurements of Neutrino Charged Current Interactions at SciBooNE

Energy Technology Data Exchange (ETDEWEB)

Nakajima, Yasuhiro [Department of Physics, Kyoto University, Kyoto 606-8502 (Japan)], E-mail: nakajima@scphys.kyoto-u.ac.jp

2009-08-15

The SciBooNE experiment (FNAL-E954) is designed to measure neutrino-nucleous cross sections in the one GeV region. Additionally, SciBooNE serves as a near detector for MiniBooNE by measuring the neutrino flux. In this paper, we describe two analyses using neutrino charged current interactions at SciBooNE: a neutrino spectrum measurement and a search for charged current coherent pion production.

SCI Longitudinal Aging Study: 40 Years of Research.

Science.gov (United States)

Krause, James S; Clark, Jillian M R; Saunders, Lee L

2015-01-01

The Spinal Cord Injury (SCI) Longitudinal Aging Study was initiated in 1973 and has conducted 8 assessments over the past 40 years. It was designed to help rehabilitation professionals understand the life situation of people with SCI, but it has developed into the most long-standing study of aging and SCI and has resulted in over 50 publications. Our purpose was to provide a detailed history of the study, response patterns, utilization of measures, and a summary of key findings reported in the literature. Five participant samples have been incorporated over the 40 years, with enrollment in 1973, 1984, 1993 (2 samples), and 2003. A total of 2,208 participants have completed 6,001 assessments, with a particularly large number of assessments among those who are more than 40 years post injury (n = 349). The overall results have indicated changing patterns of outcomes over time as persons with SCI age, with some notable declines in participation and health. There has been a survivor effect whereby persons who are more active, well-adjusted, and healthier live longer. This study has several important features that are required for longitudinal research including (a) consistency of follow-up, (b) consistency of measures over time, (c) addition of new participant samples to counteract attrition, and (d) inclusion of a large number of individuals who have reached aging milestones unparalleled in the literature. Data from this study can inform the literature on the natural course of aging with SCI.

Planet traps and first planets: The critical metallicity for gas giant formation

Energy Technology Data Exchange (ETDEWEB)

Hasegawa, Yasuhiro; Hirashita, Hiroyuki, E-mail: yasu@asiaa.sinica.edu.tw, E-mail: hirashita@asiaa.sinica.edu.tw [Institute of Astronomy and Astrophysics, Academia Sinica (ASIAA), P.O. Box 23-141, Taipei 10617, Taiwan (China)

2014-06-10

The ubiquity of planets poses an interesting question: when are first planets formed in galaxies? We investigate this by adopting a theoretical model where planet traps are combined with the standard core accretion scenario in which the efficiency of forming planetary cores directly relates to the metallicity ([Fe/H]) in disks. Three characteristic exoplanetary populations are examined: hot Jupiters, exo-Jupiters around 1 AU, and low-mass planets in tight orbits, such as super-Earths. We statistically compute planet formation frequencies (PFFs), as well as the orbital radius (〈R{sub rapid}〉) within which gas accretion becomes efficient enough to form Jovian planets, as a function of metallicity (–2 ≤ [Fe/H] ≤–0.6). We show that the total PFFs for these three populations increase steadily with metallicity. This is the direct outcome of the core accretion picture. For the metallicity range considered here, the population of low-mass planets dominates Jovian planets. The Jovian planets contribute to the PFFs above [Fe/H] ≅ –1. We find that the hot Jupiters form more efficiently than the exo-Jupiters at [Fe/H] ≲ –0.7. This arises from the slower growth of planetary cores and their more efficient radial inward transport by the host traps in lower metallicity disks. We show that the critical metallicity for forming Jovian planets is [Fe/H] ≅ –1.2 by comparing 〈R{sub rapid}〉 of hot Jupiters and low-mass planets. The comparison intrinsically links to the different gas accretion efficiency between these two types of planets. Therefore, this study implies that important physical processes in planet formation may be tested by exoplanet observations around metal-poor stars.

Planet traps and first planets: The critical metallicity for gas giant formation

International Nuclear Information System (INIS)

Hasegawa, Yasuhiro; Hirashita, Hiroyuki

2014-01-01

The ubiquity of planets poses an interesting question: when are first planets formed in galaxies? We investigate this by adopting a theoretical model where planet traps are combined with the standard core accretion scenario in which the efficiency of forming planetary cores directly relates to the metallicity ([Fe/H]) in disks. Three characteristic exoplanetary populations are examined: hot Jupiters, exo-Jupiters around 1 AU, and low-mass planets in tight orbits, such as super-Earths. We statistically compute planet formation frequencies (PFFs), as well as the orbital radius (〈R rapid 〉) within which gas accretion becomes efficient enough to form Jovian planets, as a function of metallicity (–2 ≤ [Fe/H] ≤–0.6). We show that the total PFFs for these three populations increase steadily with metallicity. This is the direct outcome of the core accretion picture. For the metallicity range considered here, the population of low-mass planets dominates Jovian planets. The Jovian planets contribute to the PFFs above [Fe/H] ≅ –1. We find that the hot Jupiters form more efficiently than the exo-Jupiters at [Fe/H] ≲ –0.7. This arises from the slower growth of planetary cores and their more efficient radial inward transport by the host traps in lower metallicity disks. We show that the critical metallicity for forming Jovian planets is [Fe/H] ≅ –1.2 by comparing 〈R rapid 〉 of hot Jupiters and low-mass planets. The comparison intrinsically links to the different gas accretion efficiency between these two types of planets. Therefore, this study implies that important physical processes in planet formation may be tested by exoplanet observations around metal-poor stars.

Modeling the secular evolution of migrating planet pairs

Science.gov (United States)

Michtchenko, T. A.; Rodríguez, A.

2011-10-01

The secular regime of motion of multi-planetary systems is universal; in contrast with the 'accidental' resonant motion, characteristic only for specific configurations of the planets, secular motion is present everywhere in phase space, even inside the resonant region. The secular behavior of a pair of planets evolving under dissipative forces is the principal subject of this study, particularly, the case when the dissipative forces affect the planetary semi-major axes and the planets move inward/outward the central star, the process known as planet migration. Based on the fundamental concepts of conservative and dissipative dynamics of the three-body problem, we develop a qualitative model of the secular evolution of the migrating planetary pair. Our approach is based on analysis of the energy and the orbital angular momentum exchange between the two-planet system and an external medium; thus no specific kind of dissipative forces is invoked. We show that, under assumption that dissipation is weak and slow, the evolutionary routes of the migrating planets are traced by the Mode I and Mode II stationary solutions of the conservative secular problem. The ultimate convergence and the evolution of the system along one of these secular modes of motion is determined uniquely by the condition that the dissipation rate is sufficiently smaller than the proper secular frequency of the system. We show that it is possible to reassemble the starting configurations and migration history of the systems on the basis of their final states and consequently to constrain the parameters of the physical processes involved.

Using thermal phase curves to probe the climate of potentially habitable planets

Science.gov (United States)

Kataria, Tiffany

2018-01-01

Thermal phase-curve observations probe the variation in emitted flux of a planet with phase, or longitude. When conducted spectroscopically, they allow us to probe the two-dimensional temperature structure in both longitude and altitude, which directly relate to the planet’s circulation and chemistry. In the case of small, potentially habitable exoplanets, spectroscopic phase-curve observations can provide us with direct evidence that the planet is capable of sustaining liquid water from measurements of its brightness temperature, and allow us to distinguish between a ‘airless’ body and one that has an appreciable atmosphere. In this talk I will summarize efforts to characterize exoplanets smaller than Neptune with phase-curve observations and emission spectroscopy using the Spitzer and Hubble Space Telescopes. I will then discuss how these ‘lessons learned’ can be applied to future efforts to characterize potentially habitable planets with phase-curve observations using JWST and future facilities such as the Origins Space Telescope (OST).

Academic Training - Exploring Planets and Moons in our Solar System

CERN Multimedia

Françoise Benz

2006-01-01

2005-2006 ACADEMIC TRAINING PROGRAMME LECTURE SERIES 6, 7, 8, 9 June 11:00-12:00. On the 8 June from 10:00 to 12:00 - Auditorium, bldg 500 Exploring Planets and Moons in our Solar System H.O. RUCKER / Space Research Institut, Graz The lecture series comprises 5 lectures starting with the interplanetary medium, the solar wind and its interaction with magnetized planets. Knowledge on the magnetically dominated 'spheres'around the Giant Planets have been obtained by the Grand Tour of both Voyager spacecraft to Jupiter, Saturn, with the continuation of Voyager 2 to Uranus, and Neptune, in the late seventies and eighties of last century. These findings are now extensively supported and complemented by Cassini/Huygens to the Saturnian system. This will be discussed in detail in lecture 2. Specific aspects of magnetospheric physics, in particular radio emissions from the planets, observed in-situ and by remote sensing techniques, will be addressed in the following lecture 3. Of high importance are also the rec...

PLANET-PLANET SCATTERING LEADS TO TIGHTLY PACKED PLANETARY SYSTEMS

International Nuclear Information System (INIS)

Raymond, Sean N.; Barnes, Rory; Veras, Dimitri; Armitage, Philip J.; Gorelick, Noel; Greenberg, Richard

2009-01-01

The known extrasolar multiple-planet systems share a surprising dynamical attribute: they cluster just beyond the Hill stability boundary. Here we show that the planet-planet scattering model, which naturally explains the observed exoplanet eccentricity distribution, can reproduce the observed distribution of dynamical configurations. We calculated how each of our scattered systems would appear over an appropriate range of viewing geometries; as Hill stability is weakly dependent on the masses, the mass-inclination degeneracy does not significantly affect our results. We consider a wide range of initial planetary mass distributions and find that some are poor fits to the observed systems. In fact, many of our scattering experiments overproduce systems very close to the stability boundary. The distribution of dynamical configurations of two-planet systems may provide better discrimination between scattering models than the distribution of eccentricity. Our results imply that, at least in their inner regions which are weakly affected by gas or planetesimal disks, planetary systems should be 'packed', with no large gaps between planets.

SciDAC advances and applications in computational beam dynamics

International Nuclear Information System (INIS)

Ryne, R; Abell, D; Adelmann, A; Amundson, J; Bohn, C; Cary, J; Colella, P; Dechow, D; Decyk, V; Dragt, A; Gerber, R; Habib, S; Higdon, D; Katsouleas, T; Ma, K-L; McCorquodale, P; Mihalcea, D; Mitchell, C; Mori, W; Mottershead, C T; Neri, F; Pogorelov, I; Qiang, J; Samulyak, R; Serafini, D; Shalf, J; Siegerist, C; Spentzouris, P; Stoltz, P; Terzic, B; Venturini, M; Walstrom, P

2005-01-01

SciDAC has had a major impact on computational beam dynamics and the design of particle accelerators. Particle accelerators-which account for half of the facilities in the DOE Office of Science Facilities for the Future of Science 20 Year Outlook-are crucial for US scientific, industrial, and economic competitiveness. Thanks to SciDAC, accelerator design calculations that were once thought impossible are now carried routinely, and new challenging and important calculations are within reach. SciDAC accelerator modeling codes are being used to get the most science out of existing facilities, to produce optimal designs for future facilities, and to explore advanced accelerator concepts that may hold the key to qualitatively new ways of accelerating charged particle beams. In this paper we present highlights from the SciDAC Accelerator Science and Technology (AST) project Beam Dynamics focus area in regard to algorithm development, software development, and applications

SciDAC Advances and Applications in Computational Beam Dynamics

International Nuclear Information System (INIS)

Ryne, R.; Abell, D.; Adelmann, A.; Amundson, J.; Bohn, C.; Cary, J.; Colella, P.; Dechow, D.; Decyk, V.; Dragt, A.; Gerber, R.; Habib, S.; Higdon, D.; Katsouleas, T.; Ma, K.-L.; McCorquodale, P.; Mihalcea, D.; Mitchell, C.; Mori, W.; Mottershead, C.T.; Neri, F.; Pogorelov, I.; Qiang, J.; Samulyak, R.; Serafini, D.; Shalf, J.; Siegerist, C.; Spentzouris, P.; Stoltz, P.; Terzic, B.; Venturini, M.; Walstrom, P.

2005-01-01

SciDAC has had a major impact on computational beam dynamics and the design of particle accelerators. Particle accelerators--which account for half of the facilities in the DOE Office of Science Facilities for the Future of Science 20 Year Outlook--are crucial for US scientific, industrial, and economic competitiveness. Thanks to SciDAC, accelerator design calculations that were once thought impossible are now carried routinely, and new challenging and important calculations are within reach. SciDAC accelerator modeling codes are being used to get the most science out of existing facilities, to produce optimal designs for future facilities, and to explore advanced accelerator concepts that may hold the key to qualitatively new ways of accelerating charged particle beams. In this poster we present highlights from the SciDAC Accelerator Science and Technology (AST) project Beam Dynamics focus area in regard to algorithm development, software development, and applications

Planet-planet scattering leads to tightly packed planetary systems

OpenAIRE

Raymond, Sean N.; Barnes, Rory; Veras, Dimitri; Armitage, Philip J.; Gorelick, Noel; Greenberg, Richard

2009-01-01

The known extrasolar multiple-planet systems share a surprising dynamical attribute: they cluster just beyond the Hill stability boundary. Here we show that the planet-planet scattering model, which naturally explains the observed exoplanet eccentricity distribution, can reproduce the observed distribution of dynamical configurations. We calculated how each of our scattered systems would appear over an appropriate range of viewing geometries; as Hill stability is weakly dependent on the masse...

Influence of stellar multiplicity on planet formation. I. Evidence of suppressed planet formation due to stellar companions within 20 au and validation of four planets from the Kepler multiple planet candidates

International Nuclear Information System (INIS)

Wang, Ji; Fischer, Debra A.; Xie, Ji-Wei; Barclay, Thomas

2014-01-01

The planet occurrence rate for multiple stars is important in two aspects. First, almost half of stellar systems in the solar neighborhood are multiple systems. Second, the comparison of the planet occurrence rate for multiple stars to that for single stars sheds light on the influence of stellar multiplicity on planet formation and evolution. We developed a method of distinguishing planet occurrence rates for single and multiple stars. From a sample of 138 bright (K P < 13.5) Kepler multi-planet candidate systems, we compared the stellar multiplicity rate of these planet host stars to that of field stars. Using dynamical stability analyses and archival Doppler measurements, we find that the stellar multiplicity rate of planet host stars is significantly lower than field stars for semimajor axes less than 20 AU, suggesting that planet formation and evolution are suppressed by the presence of a close-in companion star at these separations. The influence of stellar multiplicity at larger separations is uncertain because of search incompleteness due to a limited Doppler observation time baseline and a lack of high-resolution imaging observation. We calculated the planet confidence for the sample of multi-planet candidates and find that the planet confidences for KOI 82.01, KOI 115.01, KOI 282.01, and KOI 1781.02 are higher than 99.7% and thus validate the planetary nature of these four planet candidates. This sample of bright Kepler multi-planet candidates with refined stellar and orbital parameters, planet confidence estimation, and nearby stellar companion identification offers a well-characterized sample for future theoretical and observational study.

BlockSci: Design and applications of a blockchain analysis platform

OpenAIRE

Kalodner, Harry; Goldfeder, Steven; Chator, Alishah; Möser, Malte; Narayanan, Arvind

2017-01-01

Analysis of blockchain data is useful for both scientific research and commercial applications. We present BlockSci, an open-source software platform for blockchain analysis. BlockSci is versatile in its support for different blockchains and analysis tasks. It incorporates an in-memory, analytical (rather than transactional) database, making it several hundred times faster than existing tools. We describe BlockSci's design and present four analyses that illustrate its capabilities. This is a ...

Analysis of Sci-Hub downloads of computer science papers

Directory of Open Access Journals (Sweden)

Andročec Darko

2017-07-01

Full Text Available The scientific knowledge is disseminated by research papers. Most of the research literature is copyrighted by publishers and avail- able only through paywalls. Recently, some websites offer most of the recent content for free. One of them is the controversial website Sci-Hub that enables access to more than 47 million pirated research papers. In April 2016, Science Magazine published an article on Sci-Hub activity over the period of six months and publicly released the Sci-Hub’s server log data. The mentioned paper aggregates the view that relies on all downloads and for all fields of study, but these findings might be hiding interesting patterns within computer science. The mentioned Sci-Hub log data was used in this paper to analyse downloads of computer science papers based on DBLP’s list of computer science publications. The top downloads of computer science papers were analysed, together with the geographical location of Sci-Hub users, the most downloaded publishers, types of papers downloaded, and downloads of computer science papers per publication year. The results of this research can be used to improve legal access to the most relevant scientific repositories or journals for the computer science field.

Cross sections for electron-impact excitation of the H2 molecule using the MOB-SCI strategy

International Nuclear Information System (INIS)

Costa, Romarly F da; Paixao, Fernando J da; Lima, Marco A P

2005-01-01

In this paper, we report integral and differential cross sections for the electronic excitation of H 2 molecules by electron-impact. Our scattering amplitudes were calculated using the Schwinger multichannel method within the minimal orbital basis for single configuration interactions (MOB-SCI) level of approximation. Through the use of the present strategy we have investigated the coupling effects among ground state and first singlet and triplet states of the same spatial symmetry. The five-state (nine for degenerated states) close-coupling calculations joined the advantages of a well-described set of physical states of interest with a minimum associated pseudo-state space. The results obtained by means of the MOB-SCI technique show a significant improvement towards experimental data in comparison with previous two-channel close-coupling calculations

Treatment of Nueropathic Pain after SCI with a Catalytic Oxidoreductant

Science.gov (United States)

2016-10-01

include under the details per task section below. Although we did not find an effect of BuOE2 in reducing functional deficits following ischemic SCI, we...SCI. Epidermal growth factor (EGF) is a protein that supports cell proliferation. An upregulation following injury was observed in the epicenter...Figure 25: Effect of BuOE2 on expression of leptin in the rat spinal cord at 24 hours post-SCI. Leptin is a hormone which regulates energy homeostasis

Sex and Fertility After SCI

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Full Text Available ... Pediatric SCI Rehabilitation Sara Klaas, MSW Transitions for Children with Spinal Cord Injury Patricia Mucia, RN Family ... play_arrow How is the delivery of a child affected by the mother's spinal cord injury? play_ ...

Sex and Fertility After SCI

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Full Text Available ... SCI Rehabilitation Donald Peck Leslie, MD Adjusting to Social Life in a Wheelchair Lisa Rosen, MS Spasticity, ... OT Anne Bryden, OT The Role of the Social Worker after Spinal Cord Injury Patti Rogers, SW ...

Women's Sexual Health and Reproductive Function After SCI.

Science.gov (United States)

Courtois, Frédérique; Alexander, Marcalee; McLain, Amie B Jackson

2017-01-01

Sexual function and to a lesser extent reproduction are often disrupted in women with spinal cord injuries (SCI), who must be educated to better understand their sexual and reproductive health. Women with SCI are sexually active; they can use psychogenic or reflexogenic stimulation to obtain sexual pleasure and orgasm. Treatment should consider a holistic approach using autonomic standards to describe remaining sexual function and to assess both genital function and psychosocial factors. Assessment of genital function should include thoracolumbar dermatomes, vulvar sensitivity (touch, pressure, vibration), and sacral reflexes. Self-exploration should include not only clitoral stimulation, but also stimulation of the vagina (G spot), cervix, and nipples conveyed by different innervation sources. Treatments may consider PDE5 inhibitors and flibanserin on an individual basis, and secondary consequences of SCI should address concerns with spasticity, pain, incontinence, and side effects of medications. Psychosocial issues must be addressed as possible contributors to sexual dysfunctions (eg, lower self-esteem, past sexual history, depression, dating habits). Pregnancy is possible for women with SCI; younger age at the time of injury and at the time of pregnancy being significant predictors of successful pregnancy, along with marital status, motor score, mobility, and occupational scores. Pregnancy may decrease the level of functioning (eg, self-care, ambulation, upper-extremity tasks), may involve complications (eg, decubitus ulcers, weight gain, urological complications), and must be monitored for postural hypotension and autonomic dysreflexia. Taking into consideration the physical and psychosocial determinants of sexuality and childbearing allows women with SCI to achieve positive sexual and reproductive health.

Discontinuous ventilator weaning of patients with acute SCI.

Science.gov (United States)

Füssenich, Wout; Hirschfeld Araujo, Sven; Kowald, Birgitt; Hosman, Allard; Auerswald, Marc; Thietje, Roland

2018-05-01

Retrospective, single centre cohort study. To determine factors associated with ventilator weaning success and failure in patients with acute spinal cord injury (SCI); determine length of time and attempts required to wean from the ventilator successfully and determine the incidence of pneumonia. BG Klinikum Hamburg, Level 1 trauma centre, SCI Department, Germany. From 2010 until 2017, 165 consecutive patients with cervical SCI, initially dependent on a ventilator, were included and weaned discontinuously via tracheal cannula. Data related to anthropometric details, neurological injury, respiratory outcomes, and weaning parameters were prospectively recorded in a database and retrospectively analysed. Seventy-nine percent of all patients were successfully weaned from ventilation. Average duration of the complete weaning process was 37 days. Ninety-one percent of the successfully weaned patients completed this on first attempt. Age (>56 years), level of injury (C4 and/or above), vital capacity (25 kg/m 2 ), and chronic obstructive pulmonary disease (COPD) significantly decreased the chance of successful weaning. These factors also correlated with a higher number of weaning attempts. High level of injury, older age, and reduced vital capacity also increased the duration of the weaning process. Patients with low vital capacity and concurrent therapy with Baclofen and Dantrolene showed higher rates of pneumonia. We conclude that mentioned factors are associated with weaning outcome and useful for clinical recommendations and patient counselling. These data further support the complexity of ventilator weaning in the SCI population due to associated complications, therefore we recommend conducting weaning of patients with SCI on intensive or intermediate care units (ICU/IMCU) in specialised centres.

ScienceDirect through SciVerse: a new way to approach Elsevier.

Science.gov (United States)

Bengtson, Jason

2011-01-01

SciVerse is the new combined portal from Elsevier that services their ScienceDirect collection, SciTopics, and their Scopus database. Using SciVerse to access ScienceDirect is the specific focus of this review. Along with advanced keyword searching and citation searching options, SciVerse also incorporates a very useful image search feature. The aim seems to be not only to create an interface that provides broad functionality on par with other database search tools that many searchers use regularly but also to create an open platform that could be changed to respond effectively to the needs of customers.

Sex and Fertility After SCI

Medline Plus

Full Text Available ... Diane M. Rowles, MS, NP How Family Life Changes After Spinal Cord Injury Nancy Rosenberg, PsyD Understanding SCI Rehabilitation Donald Peck Leslie, MD Adjusting to Social Life in a Wheelchair Lisa Rosen, MS Spasticity, ...

Sex and Fertility After SCI

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Full Text Available menu Understanding Spinal Cord Injury What is a Spinal Cord Injury Levels of Injury and What They Mean Animated Spinal Cord Injury Chart Spinal Cord Injury Facts and Figures Care and Treatment After SCI Spinal ...

Sex and Fertility After SCI

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Full Text Available ... RN Pediatric Injuries Pediatric Spinal Cord Injury 101 Lawrence Vogel, MD The Basics of Pediatric SCI Rehabilitation ... Rogers, PT Recreational Therapy after Spinal Cord Injury Jennifer Piatt, PhD Diane M. Rowles, MS, NP Read ...

Sex and Fertility After SCI

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Full Text Available ... Adult Injuries Spinal Cord Injury 101 David Chen, MD Preventing Pressure Sores Mary Zeigler, MS Transition from ... Rosenberg, PsyD Understanding SCI Rehabilitation Donald Peck Leslie, MD Adjusting to Social Life in a Wheelchair Lisa ...

Study of Power Options for Jupiter and Outer Planet Missions

Science.gov (United States)

Landis, Geoffrey A.; Fincannon, James

2015-01-01

Power for missions to Jupiter and beyond presents a challenging goal for photovoltaic power systems, but NASA missions including Juno and the upcoming Europa Clipper mission have shown that it is possible to operate solar arrays at Jupiter. This work analyzes photovoltaic technologies for use in Jupiter and outer planet missions, including both conventional arrays, as well as analyzing the advantages of advanced solar cells, concentrator arrays, and thin film technologies. Index Terms - space exploration, spacecraft solar arrays, solar electric propulsion, photovoltaic cells, concentrator, Fresnel lens, Jupiter missions, outer planets.

Infrared radiation scene generation of stars and planets in celestial background

Science.gov (United States)

Guo, Feng; Hong, Yaohui; Xu, Xiaojian

2014-10-01

An infrared (IR) radiation generation model of stars and planets in celestial background is proposed in this paper. Cohen's spectral template1 is modified for high spectral resolution and accuracy. Based on the improved spectral template for stars and the blackbody assumption for planets, an IR radiation model is developed which is able to generate the celestial IR background for stars and planets appearing in sensor's field of view (FOV) for specified observing date and time, location, viewpoint and spectral band over 1.2μm ~ 35μm. In the current model, the initial locations of stars are calculated based on midcourse space experiment (MSX) IR astronomical catalogue (MSX-IRAC) 2 , while the initial locations of planets are calculated using secular variations of the planetary orbits (VSOP) theory. Simulation results show that the new IR radiation model has higher resolution and accuracy than common model.

The ocean planet.

Science.gov (United States)

Hinrichsen, D

1998-01-01

The Blue Planet is 70% water, and all but 3% of it is salt water. Life on earth first evolved in the primordial soup of ancient seas, and though today's seas provide 99% of all living space on the planet, little is known about the world's oceans. However, the fact that the greatest threats to the integrity of our oceans come from land-based activities is becoming clear. Humankind is in the process of annihilating the coastal and ocean ecosystems and the wealth of biodiversity they harbor. Mounting population and development pressures have taken a grim toll on coastal and ocean resources. The trend arising from such growth is the chronic overexploitation of marine resources, whereby rapidly expanding coastal populations and the growth of cities have contributed to a rising tide of pollution in nearly all of the world's seas. This crisis is made worse by government inaction and a frustrating inability to enforce existing coastal and ocean management regulations. Such inability is mainly because concerned areas contain so many different types of regulations and involve so many levels of government, that rational planning and coordination of efforts are rendered impossible. Concerted efforts are needed by national governments and the international community to start preserving the ultimate source of all life on earth.

Addressing the statistical mechanics of planet orbits in the solar system

Science.gov (United States)

Mogavero, Federico

2017-10-01

The chaotic nature of planet dynamics in the solar system suggests the relevance of a statistical approach to planetary orbits. In such a statistical description, the time-dependent position and velocity of the planets are replaced by the probability density function (PDF) of their orbital elements. It is natural to set up this kind of approach in the framework of statistical mechanics. In the present paper, I focus on the collisionless excitation of eccentricities and inclinations via gravitational interactions in a planetary system. The future planet trajectories in the solar system constitute the prototype of this kind of dynamics. I thus address the statistical mechanics of the solar system planet orbits and try to reproduce the PDFs numerically constructed by Laskar (2008, Icarus, 196, 1). I show that the microcanonical ensemble of the Laplace-Lagrange theory accurately reproduces the statistics of the giant planet orbits. To model the inner planets I then investigate the ansatz of equiprobability in the phase space constrained by the secular integrals of motion. The eccentricity and inclination PDFs of Earth and Venus are reproduced with no free parameters. Within the limitations of a stationary model, the predictions also show a reasonable agreement with Mars PDFs and that of Mercury inclination. The eccentricity of Mercury demands in contrast a deeper analysis. I finally revisit the random walk approach of Laskar to the time dependence of the inner planet PDFs. Such a statistical theory could be combined with direct numerical simulations of planet trajectories in the context of planet formation, which is likely to be a chaotic process.

"Sci-Tech - Couldn't be without it !"

Science.gov (United States)

2002-03-01

Launch of a Major European Outreach Programme Seven of Europe's leading Research Organizations [1] launch joint outreach programme for the European Science and Technology Week at the Technopolis Museum in Brussels on 22 March. Their aim is to show Europeans how today's society couldn't be without fundamental research . Could you imagine life without mobile phones, cars, CD players, TV, refrigerators, computers, the internet and the World Wide Web, antibiotics, vitamins, anaesthetics, vaccination, heating, pampers, nylon stockings, glue, bar codes, metal detectors, contact lenses, modems, laser printers, digital cameras, gameboys, play stations...? Technology is everywhere and used by everyone in today's society, but how many Europeans suspect that without studies on the structure of the atom, lasers would not exist, and neither would CD players? Most do not realise that most things they couldn't be without have required years of fundamental research . To fill this knowledge gap, the leading Research Organizations in Europe [1], with the support of the research directorate of the European Commission, have joined forces to inform Europeans how technology couldn't be without science, and how science can no longer progress without technology. The project is called...... Sci-Tech - Couldn't be without it! Sci-Tech - Couldn't be without it! invites Europeans to vote online in a survey to identify the top ten technologies they can't live without. It will show them through a dynamic and entertaining Web space where these top technologies really come from, and it will reveal their intimate links with research. Teaching kits will be developed to explain to students how their favourite gadgets actually work, and how a career in science can contribute to inventions that future generations couldn't be without. The results of the survey will be presented as a series of quiz shows live on the Internet during the Science Week, from 4 to 10 November. Sci-tech - Couldn't be without

The Now Frontier. Pioneer to Jupiter. Man Links Earth and Planets. Issue No. 1-5.

Science.gov (United States)

1973

This packet of space science instructional materials includes five issues related to the planet Jupiter. Each issue presents factual material about the planet, diagramatic representations of its movements and positions relative to bright stars or the earth, actual photographs and/or tables of data collected relevant to Pioneer 10, the spacecraft…

Sex and Fertility After SCI

Medline Plus

Full Text Available ... Spinal Cord Injury 101 Lawrence Vogel, MD The Basics of Pediatric SCI Rehabilitation Sara Klaas, MSW Transitions for Children with Spinal Cord Injury Patricia Mucia, RN Family Life After Pediatric Spinal Injury Dawn Sheaffer, MSW Rehabilitation ...

Preface: SciDAC 2008

Science.gov (United States)

Stevens, Rick

2008-07-01

The fourth annual Scientific Discovery through Advanced Computing (SciDAC) Conference was held June 13-18, 2008, in Seattle, Washington. The SciDAC conference series is the premier communitywide venue for presentation of results from the DOE Office of Science's interdisciplinary computational science program. Started in 2001 and renewed in 2006, the DOE SciDAC program is the country's - and arguably the world's - most significant interdisciplinary research program supporting the development of advanced scientific computing methods and their application to fundamental and applied areas of science. SciDAC supports computational science across many disciplines, including astrophysics, biology, chemistry, fusion sciences, and nuclear physics. Moreover, the program actively encourages the creation of long-term partnerships among scientists focused on challenging problems and computer scientists and applied mathematicians developing the technology and tools needed to address those problems. The SciDAC program has played an increasingly important role in scientific research by allowing scientists to create more accurate models of complex processes, simulate problems once thought to be impossible, and analyze the growing amount of data generated by experiments. To help further the research community's ability to tap into the capabilities of current and future supercomputers, Under Secretary for Science, Raymond Orbach, launched the Innovative and Novel Computational Impact on Theory and Experiment (INCITE) program in 2003. The INCITE program was conceived specifically to seek out computationally intensive, large-scale research projects with the potential to significantly advance key areas in science and engineering. The program encourages proposals from universities, other research institutions, and industry. During the first two years of the INCITE program, 10 percent of the resources at NERSC were allocated to INCITE awardees. However, demand for supercomputing resources

Measurement of Bone: Diagnosis of SCI-Induced Osteoporosis and Fracture Risk Prediction.

Science.gov (United States)

Troy, Karen L; Morse, Leslie R

2015-01-01

Spinal cord injury (SCI) is associated with a rapid loss of bone mass, resulting in severe osteoporosis and a 5- to 23-fold increase in fracture risk. Despite the seriousness of fractures in SCI, there are multiple barriers to osteoporosis diagnosis and wide variations in treatment practices for SCI-induced osteoporosis. We review the biological and structural changes that are known to occur in bone after SCI in the context of promoting future research to prevent or reduce risk of fracture in this population. We also review the most commonly used methods for assessing bone after SCI and discuss the strengths, limitations, and clinical applications of each method. Although dual-energy x-ray absorptiometry assessments of bone mineral density may be used clinically to detect changes in bone after SCI, 3-dimensional methods such as quantitative CT analysis are recommended for research applications and are explained in detail.

On the Stability of Deinoxanthin Exposed to Mars Conditions during a Long-Term Space Mission and Implications for Biomarker Detection on Other Planets

Directory of Open Access Journals (Sweden)

Stefan Leuko

2017-09-01

Full Text Available Outer space, the final frontier, is a hostile and unforgiving place for any form of life as we know it. The unique environment of space allows for a close simulation of Mars surface conditions that cannot be simulated as accurately on the Earth. For this experiment, we tested the resistance of Deinococcus radiodurans to survive exposure to simulated Mars-like conditions in low-Earth orbit for a prolonged period of time as part of the Biology and Mars experiment (BIOMEX project. Special focus was placed on the integrity of the carotenoid deinoxanthin, which may serve as a potential biomarker to search for remnants of life on other planets. Survival was investigated by evaluating colony forming units, damage inflicted to the 16S rRNA gene by quantitative PCR, and the integrity and detectability of deinoxanthin by Raman spectroscopy. Exposure to space conditions had a strong detrimental effect on the survival of the strains and the 16S rRNA integrity, yet results show that deinoxanthin survives exposure to conditions as they prevail on Mars. Solar radiation is not only strongly detrimental to the survival and 16S rRNA integrity but also to the Raman signal of deinoxanthin. Samples not exposed to solar radiation showed only minuscule signs of deterioration. To test whether deinoxanthin is able to withstand the tested parameters without the protection of the cell, it was extracted from cell homogenate and exposed to high/low temperatures, vacuum, germicidal UV-C radiation, and simulated solar radiation. Results obtained by Raman investigations showed a strong resistance of deinoxanthin against outer space and Mars conditions, with the only exception of the exposure to simulated solar radiation. Therefore, deinoxanthin proved to be a suitable easily detectable biomarker for the search of Earth-like organic pigment-containing life on other planets.

Dawn of small worlds dwarf planets, asteroids, comets

CERN Document Server

Moltenbrey, Michael

2016-01-01

This book gives a detailed introduction to the thousands and thousands of smaller bodies in the solar system. Written for interested laymen, amateur astronomers and students it describes the nature and origin of asteroids, dwarf planets and comets, and gives detailed information about their role in the solar system. The author nicely reviews the history of small-world-exploration and describes past, current and future space craft missions studying small worlds, and presents their results. Readers will learn that small solar system worlds have a dramatically different nature and appearance than the planets. Even though research activity on small worlds has increased in the recent past many of their properties are still in the dark and need further research.

Circulating sclerostin is elevated in short-term and reduced in long-term SCI.

Science.gov (United States)

Battaglino, Ricardo A; Sudhakar, Supreetha; Lazzari, Antonio A; Garshick, Eric; Zafonte, Ross; Morse, Leslie R

2012-09-01

Spinal cord injury (SCI) causes profound bone loss due to muscle paralysis resulting in the inability to walk. Sclerostin, a Wnt signaling pathway antagonist produced by osteocytes, is a potent inhibitor of bone formation. Short-term studies in rodent models have demonstrated increased sclerostin in response to mechanical unloading that is reversed with reloading. Although sclerostin inhibition has been proposed as a potential therapy for bone loss, it is not known if sclerostin levels vary with duration of SCI in humans. We analyzed circulating sclerostin in 155 men with varying degrees of SCI who were 1 year or more post-injury. We report that sclerostin levels are greatest in subjects with short-term SCI (≤5 years post-injury) and decrease significantly over the first 5 years post-injury. There was no association between sclerostin and injury duration in subjects with long-term SCI (>5 years post-injury). In subjects with long-term SCI, sclerostin levels were positively associated with lower extremity bone density and bone mineral content. These data suggest that sclerostin levels are initially increased after SCI in response to mechanical unloading. This response is time-limited and as bone loss progresses, circulating sclerostin is lowest in subjects with severe osteoporosis. These findings support a dual role for sclerostin after SCI: a therapeutic target in acute SCI, and a biomarker of osteoporosis severity in chronic SCI. Copyright © 2012 Elsevier Inc. All rights reserved.

The hottest planet.

Science.gov (United States)

Harrington, Joseph; Luszcz, Statia; Seager, Sara; Deming, Drake; Richardson, L Jeremy

2007-06-07

Of the over 200 known extrasolar planets, just 14 pass in front of and behind their parent stars as seen from Earth. This fortuitous geometry allows direct determination of many planetary properties. Previous reports of planetary thermal emission give fluxes that are roughly consistent with predictions based on thermal equilibrium with the planets' received radiation, assuming a Bond albedo of approximately 0.3. Here we report direct detection of thermal emission from the smallest known transiting planet, HD 149026b, that indicates a brightness temperature (an expression of flux) of 2,300 +/- 200 K at 8 microm. The planet's predicted temperature for uniform, spherical, blackbody emission and zero albedo (unprecedented for planets) is 1,741 K. As models with non-zero albedo are cooler, this essentially eliminates uniform blackbody models, and may also require an albedo lower than any measured for a planet, very strong 8 microm emission, strong temporal variability, or a heat source other than stellar radiation. On the other hand, an instantaneous re-emission blackbody model, in which each patch of surface area instantly re-emits all received light, matches the data. This planet is known to be enriched in heavy elements, which may give rise to novel atmospheric properties yet to be investigated.

Overview of the Spinal Cord Injury – Quality of Life (SCI-QOL) measurement system

Science.gov (United States)

Tulsky, David S.; Kisala, Pamela A.; Victorson, David; Tate, Denise G.; Heinemann, Allen W.; Charlifue, Susan; Kirshblum, Steve C.; Fyffe, Denise; Gershon, Richard; Spungen, Ann M.; Bombardier, Charles H.; Dyson-Hudson, Trevor A.; Amtmann, Dagmar; Z. Kalpakjian, Claire; W. Choi, Seung; Jette, Alan M.; Forchheimer, Martin; Cella, David

2015-01-01

Context/Objective The Spinal Cord Injury – Quality of Life (SCI-QOL) measurement system was developed to address the shortage of relevant and psychometrically sound patient reported outcome (PRO) measures available for clinical care and research in spinal cord injury (SCI) rehabilitation. Using a computer adaptive testing (CAT) approach, the SCI-QOL builds on the Patient Reported Outcomes Measurement Information System (PROMIS) and the Quality of Life in Neurological Disorders (Neuro-QOL) initiative. This initial manuscript introduces the background and development of the SCI-QOL measurement system. Greater detail is presented in the additional manuscripts of this special issue. Design Classical and contemporary test development methodologies were employed. Qualitative input was obtained from individuals with SCI and clinicians through interviews, focus groups, and cognitive debriefing. Item pools were field tested in a multi-site sample (n = 877) and calibrated using item response theory methods. Initial reliability and validity testing was performed in a new sample of individuals with traumatic SCI (n = 245). Setting Five Model SCI System centers and one Department of Veterans Affairs Medical Center across the United States. Participants Adults with traumatic SCI. Interventions n/a Outcome Measures n/a Results The SCI-QOL consists of 19 item banks, including the SCI-Functional Index banks, and 3 fixed-length scales measuring physical, emotional, and social aspects of health-related QOL (HRQOL). Conclusion The SCI-QOL measurement system consists of psychometrically sound measures for individuals with SCI. The manuscripts in this special issue provide evidence of the reliability and initial validity of this measurement system. The SCI-QOL also links to other measures designed for a general medical population. PMID:26010962

Space Technospheres

Science.gov (United States)

Vidmachenko, A. P.; Steklov, A. F.; Primak, N. V.

2000-01-01

Two main tendencies of making the Solar System habitable are regarding nowadays: (1) making objects of the Solar System habitable; and (2) making the space of the Solar System habitable. We think that it's better to combine them. We should dezine and build settlements ('technospheres') on such objects as asteroids and comets, using their resources. That is, it is necessary to create 'space technospheres' - a long-termed human settlements in the space. To save energy resources it is necessary to use Near-Earth asteroids enriched with water ice (i. e. extinguished comets) with Near-Earth orbits. To realize listed conceptions it is necessary to decrease (up to 100 times) the cost price of the long-termed settlements. That's why even average UN country will be able to create it's own space house - artificial planet ('technosphere') and maintain life activities there. About 50-100 such artificial planets will represent the future civilization of our Solar System. At the same time Earth will stay basic, maternal planet. There is an interesting problem of correcting orbits of that objects. Orbits can be changed into circular or elongated to make them comfortable for living activities of 5000-10000 settlers, and to maintain connection with maternal planet. Technospheres with the elongated orbits are more advantageous to assimilate the Solar System. While technospheres with circular orbits suit to the industrial cycle with certain specialization. The specialization of the technosphere will depend on mine-workings and/or chosen high-technology industrial process. Because it is profitable to convert raw materials at the technosphere and then to transport finished products to the maternal planet. It worth to be mentioned that because of the low gravitation and changed life cycle technosphere settlers, new 'Columb' of the Solar System will transform into new mankind. It will happen though it is difficult to imaging this. Because long ago, when fish left the ocean, they didn

Mathematical models and methods for planet Earth

CERN Document Server

Locatelli, Ugo; Ruggeri, Tommaso; Strickland, Elisabetta

2014-01-01

In 2013 several scientific activities have been devoted to mathematical researches for the study of planet Earth. The current volume presents a selection of the highly topical issues presented at the workshop “Mathematical Models and Methods for Planet Earth”, held in Roma (Italy), in May 2013. The fields of interest span from impacts of dangerous asteroids to the safeguard from space debris, from climatic changes to monitoring geological events, from the study of tumor growth to sociological problems. In all these fields the mathematical studies play a relevant role as a tool for the analysis of specific topics and as an ingredient of multidisciplinary problems. To investigate these problems we will see many different mathematical tools at work: just to mention some, stochastic processes, PDE, normal forms, chaos theory.

Magic Planet

DEFF Research Database (Denmark)

Jacobsen, Aase Roland

2009-01-01

Med den digitale globe som omdrejningspunkt bestemmer publikum, hvilken planet, der er i fokus. Vores solsystem udforskes interaktivt. Udgivelsesdato: november......Med den digitale globe som omdrejningspunkt bestemmer publikum, hvilken planet, der er i fokus. Vores solsystem udforskes interaktivt. Udgivelsesdato: november...

Dance of the Planets

Science.gov (United States)

Riddle, Bob

2005-01-01

As students continue their monthly plotting of the planets along the ecliptic they should start to notice differences between inner and outer planet orbital motions, and their relative position or separation from the Sun. Both inner and outer planets have direct eastward motion, as well as retrograde motion. Inner planets Mercury and Venus,…

Strategies for Constraining the Atmospheres of Temperate Terrestrial Planets with JWST

Science.gov (United States)

Batalha, Natasha E.; Lewis, Nikole K.; Line, Michael R.; Valenti, Jeff; Stevenson, Kevin

2018-04-01

The Transiting Exoplanet Survey Satellite (TESS) is expected to discover dozens of temperate terrestrial planets orbiting M-dwarfs with atmospheres that could be followed up with the James Webb Space Telescope (JWST). Currently, the TRAPPIST-1 system serves as a benchmark for determining the feasibility and resources required to yield atmospheric constraints. We assess these questions and leverage an information content analysis to determine observing strategies for yielding high-precision spectroscopy in transmission and emission. Our goal is to guide observing strategies of temperate terrestrial planets in preparation for the early JWST cycles. First, we explore JWST’s current capabilities and expected spectral precision for targets near the saturation limits of specific modes. In doing so, we highlight the enhanced capabilities of high-efficiency readout patterns that are being considered for implementation in Cycle 2. We propose a partial saturation strategy to increase the achievable precision of JWST's NIRSpec Prism. We show that JWST has the potential to detect the dominant absorbing gas in the atmospheres of temperate terrestrial planets by the 10th transit using transmission spectroscopy techniques in the near-infrared (NIR). We also show that stacking ⪆10 transmission spectroscopy observations is unlikely to yield significant improvements in determining atmospheric composition. For emission spectroscopy, we show that the MIRI Low Resolution Spectroscopy (LRS) is unlikely to provide robust constraints on the atmospheric composition of temperate terrestrial planets. Higher-precision emission spectroscopy at wavelengths longward of those accessible to MIRI LRS, as proposed in the Origins Space Telescope concept, could help improve the constraints on molecular abundances of temperate terrestrial planets orbiting M-dwarfs.

Can FES-rowing mediate bone mineral density in SCI: a pilot study.

Science.gov (United States)

Gibbons, R S; McCarthy, I D; Gall, A; Stock, C G; Shippen, J; Andrews, B J

2014-11-01

A single case study. To compare proximal tibia trabecular bone mineral density (BMD) of a participant with complete spinal cord injury (SCI), long-termed functional electrical stimulation-rowing (FES-R) trained, with previously reported SCI and non-SCI group norms. To estimate lower limb joint contact forces (JCFs) in the FES-R trained participant. UK University and orthopaedic hospital research centre. Bilateral proximal tibial trabecular BMD of the FES-R trained participant was measured using peripheral quantitative computerised tomography, and the data were compared with SCI and non-SCI groups. An instrumented four-channel FES-R system was used to measure the lower limb JCFs in the FES-R trained participant. Structurally, proximal tibial trabecular BMD was higher in the FES-R trained participant compared with the SCI group, but was less than the non-SCI group. Furthermore, left (184.7 mg cm(-3)) and right (160.7 mg cm(-3)) BMD were well above the threshold associated with non-traumatic fracture. The knee JCFs were above the threshold known to mediate BMD in SCI, but below threshold at the hip and ankle. As pathological fractures predominate in the distal femur and proximal tibia in chronic SCI patients, the fact that the FES-R trained participant's knee JCFs were above those known to partially prevent bone loss, suggests that FES-R training may provide therapeutic benefit. Although the elevated bilateral proximal tibial BMD of the FES-R participant provides circumstantial evidence of osteogenesis, this single case precludes any statement on the clinical significance. Further investigations are required involving larger numbers and additional channels of FES to increase loading at the hip and ankle.

Exploring Disks Around Planets

Science.gov (United States)

Kohler, Susanna

2017-07-01

Giant planets are thought to form in circumstellar disks surrounding young stars, but material may also accrete into a smaller disk around the planet. Weve never detected one of these circumplanetary disks before but thanks to new simulations, we now have a better idea of what to look for.Image from previous work simulating a Jupiter-mass planet forming inside a circumstellar disk. The planet has its own circumplanetary disk of accreted material. [Frdric Masset]Elusive DisksIn the formation of giant planets, we think the final phase consists of accretion onto the planet from a disk that surrounds it. This circumplanetary disk is important to understand, since it both regulates the late gas accretion and forms the birthplace of future satellites of the planet.Weve yet to detect a circumplanetary disk thus far, because the resolution needed to spot one has been out of reach. Now, however, were entering an era where the disk and its kinematics may be observable with high-powered telescopes (like the Atacama Large Millimeter Array).To prepare for such observations, we need models that predict the basic characteristics of these disks like the mass, temperature, and kinematic properties. Now a researcher at the ETH Zrich Institute for Astronomy in Switzerland, Judit Szulgyi, has worked toward this goal.Simulating CoolingSzulgyi performs a series of 3D global radiative hydrodynamic simulations of 1, 3, 5, and 10 Jupiter-mass (MJ) giant planets and their surrounding circumplanetary disks, embedded within the larger circumstellar disk around the central star.Density (left column), temperature (center), and normalized angular momentum (right) for a 1 MJ planet over temperatures cooling from 10,000 K (top) to 1,000 K (bottom). At high temperatures, a spherical circumplanetary envelope surrounds the planet, but as the planet cools, the envelope transitions around 64,000 K to a flattened disk. [Szulgyi 2017]This work explores the effects of different planet temperatures and

Seven temperate terrestrial planets around the nearby ultracool dwarf star TRAPPIST-1.

Science.gov (United States)

Gillon, Michaël; Triaud, Amaury H M J; Demory, Brice-Olivier; Jehin, Emmanuël; Agol, Eric; Deck, Katherine M; Lederer, Susan M; de Wit, Julien; Burdanov, Artem; Ingalls, James G; Bolmont, Emeline; Leconte, Jeremy; Raymond, Sean N; Selsis, Franck; Turbet, Martin; Barkaoui, Khalid; Burgasser, Adam; Burleigh, Matthew R; Carey, Sean J; Chaushev, Aleksander; Copperwheat, Chris M; Delrez, Laetitia; Fernandes, Catarina S; Holdsworth, Daniel L; Kotze, Enrico J; Van Grootel, Valérie; Almleaky, Yaseen; Benkhaldoun, Zouhair; Magain, Pierre; Queloz, Didier

2017-02-22

One aim of modern astronomy is to detect temperate, Earth-like exoplanets that are well suited for atmospheric characterization. Recently, three Earth-sized planets were detected that transit (that is, pass in front of) a star with a mass just eight per cent that of the Sun, located 12 parsecs away. The transiting configuration of these planets, combined with the Jupiter-like size of their host star-named TRAPPIST-1-makes possible in-depth studies of their atmospheric properties with present-day and future astronomical facilities. Here we report the results of a photometric monitoring campaign of that star from the ground and space. Our observations reveal that at least seven planets with sizes and masses similar to those of Earth revolve around TRAPPIST-1. The six inner planets form a near-resonant chain, such that their orbital periods (1.51, 2.42, 4.04, 6.06, 9.1 and 12.35 days) are near-ratios of small integers. This architecture suggests that the planets formed farther from the star and migrated inwards. Moreover, the seven planets have equilibrium temperatures low enough to make possible the presence of liquid water on their surfaces.

Planets a very short introduction

CERN Document Server

Rothery, David A

2010-01-01

Planets: A Very Short Introduction demonstrates the excitement, uncertainties, and challenges faced by planetary scientists, and provides an overview of our Solar System and its origins, nature, and evolution. Terrestrial planets, giant planets, dwarf planets and various other objects such as satellites (moons), asteroids, trans-Neptunian objects, and exoplanets are discussed. Our knowledge about planets has advanced over the centuries, and has expanded at a rapidly growing rate in recent years. Controversial issues are outlined, such as What qualifies as a planet? What conditions are required for a planetary body to be potentially inhabited by life? Why does Pluto no longer have planet status? And Is there life on other planets?

Characterizing the Habitable Zone Planets of Kepler Stars

Science.gov (United States)

Fischer, Debra

Planet Hunters (PH) is a well-established and successful web interface that allows citizen scientists to search for transiting planets in the NASA Kepler public archive data. Over the past 3 years, our users have made more than 20 million light curve classifications. We now have more than 300,000 users around the world. However, more than half of the Kepler data has not yet been displayed to our volunteers. In June 2014 we are launching Planet Hunters v2.0. The backend of the site has been completely redesigned. The new website is more intuitive and faster; we have improved the real-time weighting algorithm that assigns transit scores for faster and more accurate extraction of the transit events from the database. With Planet Hunters v2.0, we expect that assessments will be ten times faster, so that we have the opportunity to complete the classifications for the backlog of Kepler light curve in the next three years. There are three goals for this project. First, we will data-mine the PH classifications to search for long period planets with fewer than 5 transit events. We have demonstrated that our volunteers are efficient at detecting planets with long periods and radii greater than a few REARTH. This region of parameter space is optimal for characterizing larger planets orbiting close to the habitable zone. To build upon the citizen science efforts, we will model the light curves, search for evidence of false positives, and contribute observations of stellar spectra to refine both the stellar and orbital parameters. Second, we will carry out a careful analysis of the fraction of transits that are missed (a function of planet radius and orbital period) to derive observational incompleteness factors. The incompleteness factors will be combined with geometrical detection factors to assess the planet occurrence rate for wide separations. This is a unique scientific contribution current studies of planet occurrence rate are either restricted to orbital periods shorter

Charged-Current Neutral Pion production at SciBooNE

International Nuclear Information System (INIS)

Catala-Perez, J.

2009-01-01

SciBooNE, located in the Booster Neutrino Beam at Fermilab, collected data from June 2007 to August 2008 to accurately measure muon neutrino and anti-neutrino cross sections on carbon below 1 GeV neutrino energy. SciBooNE is studying charged current interactions. Among them, neutral pion production interactions will be the focus of this poster. The experimental signature of neutrino-induced neutral pion production is constituted by two electromagnetic cascades initiated by the conversion of the π 0 decay photons, with an additional muon in the final state for CC processes. In this poster, I will present how we reconstruct and select charged-current muon neutrino interactions producing π 0 's in SciBooNE.

Characterization and Validation of Transiting Planets in the TESS SPOC Pipeline

Science.gov (United States)

Twicken, Joseph D.; Caldwell, Douglas A.; Davies, Misty; Jenkins, Jon Michael; Li, Jie; Morris, Robert L.; Rose, Mark; Smith, Jeffrey C.; Tenenbaum, Peter; Ting, Eric; Wohler, Bill

2018-06-01

Light curves for Transiting Exoplanet Survey Satellite (TESS) target stars will be extracted and searched for transiting planet signatures in the Science Processing Operations Center (SPOC) Science Pipeline at NASA Ames Research Center. Targets for which the transiting planet detection threshold is exceeded will be processed in the Data Validation (DV) component of the Pipeline. The primary functions of DV are to (1) characterize planets identified in the transiting planet search, (2) search for additional transiting planet signatures in light curves after modeled transit signatures have been removed, and (3) perform a comprehensive suite of diagnostic tests to aid in discrimination between true transiting planets and false positive detections. DV data products include extensive reports by target, one-page summaries by planet candidate, and tabulated transit model fit and diagnostic test results. DV products may be employed by humans and automated systems to vet planet candidates identified in the Pipeline. TESS will launch in 2018 and survey the full sky for transiting exoplanets over a period of two years. The SPOC pipeline was ported from the Kepler Science Operations Center (SOC) codebase and extended for TESS after the mission was selected for flight in the NASA Astrophysics Explorer program. We describe the Data Validation component of the SPOC Pipeline. The diagnostic tests exploit the flux (i.e., light curve) and pixel time series associated with each target to support the determination of the origin of each purported transiting planet signature. We also highlight the differences between the DV components for Kepler and TESS. Candidate planet detections and data products will be delivered to the Mikulski Archive for Space Telescopes (MAST); the MAST URL is archive.stsci.edu/tess. Funding for the TESS Mission has been provided by the NASA Science Mission Directorate.

THE CALIFORNIA PLANET SURVEY. I. FOUR NEW GIANT EXOPLANETS

International Nuclear Information System (INIS)

Howard, Andrew W.; Marcy, Geoffrey W.; Peek, Kathryn M. G.; Johnson, John Asher; Fischer, Debra A.; Isaacson, Howard; Wright, Jason T.; Bernat, David; Henry, Gregory W.; Apps, Kevin; Endl, Michael; Cochran, William D.; Valenti, Jeff A.; Anderson, Jay; Piskunov, Nikolai E.

2010-01-01

We present precise Doppler measurements of four stars obtained during the past decade at Keck Observatory by the California Planet Survey (CPS). These stars, namely, HD 34445, HD 126614, HD 13931, and Gl 179, all show evidence for a single planet in Keplerian motion. We also present Doppler measurements from the Hobby-Eberly Telescope (HET) for two of the stars, HD 34445 and Gl 179, that confirm the Keck detections and significantly refine the orbital parameters. These planets add to the statistical properties of giant planets orbiting near or beyond the ice line, and merit follow-up by astrometry, imaging, and space-borne spectroscopy. Their orbital parameters span wide ranges of planetary minimum mass (M sin i = 0.38-1.9 M Jup ), orbital period (P = 2.87-11.5 yr), semimajor axis (a = 2.1-5.2 AU), and eccentricity (e = 0.02-0.41). HD 34445 b (P = 2.87 yr, M sin i = 0.79 M Jup , e = 0.27) is a massive planet orbiting an old, G-type star. We announce a planet, HD 126614 Ab, and an M dwarf, HD 126614 B, orbiting the metal-rich star HD 126614 (which we now refer to as HD 126614 A). The planet, HD 126614 Ab, has minimum mass M sin i = 0.38 M Jup and orbits the stellar primary with period P = 3.41 yr and orbital separation a = 2.3 AU. The faint M dwarf companion, HD 126614 B, is separated from the stellar primary by 489 mas (33 AU) and was discovered with direct observations using adaptive optics and the PHARO camera at Palomar Observatory. The stellar primary in this new system, HD 126614 A, has the highest measured metallicity ([Fe/H] = +0.56) of any known planet-bearing star. HD 13931 b (P = 11.5 yr, M sin i = 1.88 M Jup , e = 0.02) is a Jupiter analog orbiting a near solar twin. Gl 179 b (P = 6.3 yr, M sin i = 0.82 M Jup , e = 0.21) is a massive planet orbiting a faint M dwarf. The high metallicity of Gl 179 is consistent with the planet-metallicity correlation among M dwarfs, as documented recently by Johnson and Apps.

Observing the Atmospheres of Known Temperate Earth-sized Planets with JWST

Science.gov (United States)

Morley, Caroline V.; Kreidberg, Laura; Rustamkulov, Zafar; Robinson, Tyler; Fortney, Jonathan J.

2017-12-01

Nine transiting Earth-sized planets have recently been discovered around nearby late-M dwarfs, including the TRAPPIST-1 planets and two planets discovered by the MEarth survey, GJ 1132b and LHS 1140b. These planets are the smallest known planets that may have atmospheres amenable to detection with the James Webb Space Telescope (JWST). We present model thermal emission and transmission spectra for each planet, varying composition and surface pressure of the atmosphere. We base elemental compositions on those of Earth, Titan, and Venus and calculate the molecular compositions assuming chemical equilibrium, which can strongly depend on temperature. Both thermal emission and transmission spectra are sensitive to the atmospheric composition; thermal emission spectra are sensitive to surface pressure and temperature. We predict the observability of each planet’s atmosphere with JWST. GJ 1132b and TRAPPIST-1b are excellent targets for emission spectroscopy with JWST/MIRI, requiring fewer than 10 eclipse observations. Emission photometry for TRAPPIST-1c requires 5-15 eclipses; LHS 1140b and TRAPPIST-1d, TRAPPIST-1e, and TRAPPIST-1f, which could possibly have surface liquid water, may be accessible with photometry. Seven of the nine planets are strong candidates for transmission spectroscopy measurements with JWST, although the number of transits required depends strongly on the planets’ actual masses. Using the measured masses, fewer than 20 transits are required for a 5σ detection of spectral features for GJ 1132b and six of the TRAPPIST-1 planets. Dedicated campaigns to measure the atmospheres of these nine planets will allow us, for the first time, to probe formation and evolution processes of terrestrial planetary atmospheres beyond our solar system.

SciDB versus Spark: A Preliminary Comparison Based on an Earth Science Use Case

Science.gov (United States)

Clune, T.; Kuo, K. S.; Doan, K.; Oloso, A.

2015-12-01

We compare two Big Data technologies, SciDB and Spark, for performance, usability, and extensibility, when applied to a representative Earth science use case. SciDB is a new-generation parallel distributed database management system (DBMS) based on the array data model that is capable of handling multidimensional arrays efficiently but requires lengthy data ingest prior to analysis, whereas Spark is a fast and general engine for large scale data processing that can immediately process raw data files and thereby avoid the ingest process. Once data have been ingested, SciDB is very efficient in database operations such as subsetting. Spark, on the other hand, provides greater flexibility by supporting a wide variety of high-level tools including DBMS's. For the performance aspect of this preliminary comparison, we configure Spark to operate directly on text or binary data files and thereby limit the need for additional tools. Arguably, a more appropriate comparison would involve exploring other configurations of Spark which exploit supported high-level tools, but that is beyond our current resources. To make the comparison as "fair" as possible, we export the arrays produced by SciDB into text files (or converting them to binary files) for the intake by Spark and thereby avoid any additional file processing penalties. The Earth science use case selected for this comparison is the identification and tracking of snowstorms in the NASA Modern Era Retrospective-analysis for Research and Applications (MERRA) reanalysis data. The identification portion of the use case is to flag all grid cells of the MERRA high-resolution hourly data that satisfies our criteria for snowstorm, whereas the tracking portion connects flagged cells adjacent in time and space to form a snowstorm episode. We will report the results of our comparisons at this presentation.

The Trojan minor planets

Science.gov (United States)

Spratt, Christopher E.

1988-08-01

There are (March, 1988) 3774 minor planets which have received a permanent number. Of these, there are some whose mean distance to the sun is very nearly equal to that of Jupiter, and whose heliocentric longitudes from that planet are about 60°, so that the three bodies concerned (sun, Jupiter, minor planet) make an approximate equilateral triangle. These minor planets, which occur in two distinct groups, one preceding Jupiter and one following, have received the names of the heroes of the Trojan war. This paper concerns the 49 numbered minor planets of this group.

High Contrast Imaging of Extrasolar Planets with a Vector Vortex Coronagraph

Data.gov (United States)

National Aeronautics and Space Administration — The discovery of rocky planets orbiting their parent stars in the habitable zone, the area where the temperature is such that water is able to exist in liquid form,...

Inside-out Planet Formation. IV. Pebble Evolution and Planet Formation Timescales

Science.gov (United States)

Hu, Xiao; Tan, Jonathan C.; Zhu, Zhaohuan; Chatterjee, Sourav; Birnstiel, Tilman; Youdin, Andrew N.; Mohanty, Subhanjoy

2018-04-01

Systems with tightly packed inner planets (STIPs) are very common. Chatterjee & Tan proposed Inside-out Planet Formation (IOPF), an in situ formation theory, to explain these planets. IOPF involves sequential planet formation from pebble-rich rings that are fed from the outer disk and trapped at the pressure maximum associated with the dead zone inner boundary (DZIB). Planet masses are set by their ability to open a gap and cause the DZIB to retreat outwards. We present models for the disk density and temperature structures that are relevant to the conditions of IOPF. For a wide range of DZIB conditions, we evaluate the gap-opening masses of planets in these disks that are expected to lead to the truncation of pebble accretion onto the forming planet. We then consider the evolution of dust and pebbles in the disk, estimating that pebbles typically grow to sizes of a few centimeters during their radial drift from several tens of astronomical units to the inner, ≲1 au scale disk. A large fraction of the accretion flux of solids is expected to be in such pebbles. This allows us to estimate the timescales for individual planet formation and the entire planetary system formation in the IOPF scenario. We find that to produce realistic STIPs within reasonable timescales similar to disk lifetimes requires disk accretion rates of ∼10‑9 M ⊙ yr‑1 and relatively low viscosity conditions in the DZIB region, i.e., a Shakura–Sunyaev parameter of α ∼ 10‑4.

Planet Candidate Validation in K2 Crowded Fields

Science.gov (United States)

Rampalli, Rayna; Vanderburg, Andrew; Latham, David; Quinn, Samuel

2018-01-01

In just three years, the K2 mission has yielded some remarkable outcomes with the discovery of over 100 confirmed planets and 500 reported planet candidates to be validated. One challenge with this mission is the search for planets located in star-crowded regions. Campaign 13 is one such example, located towards the galactic plane in the constellation of Taurus. We subject the potential planetary candidates to a validation process involving spectroscopy to derive certain stellar parameters. Seeing-limited on/off imaging follow-up is also utilized in order to rule out false positives due to nearby eclipsing binaries. Using Markov chain Monte Carlo analysis, the best-fit parameters for each candidate are generated. These will be suitable for finding a candidate’s false positive probability through methods including feeding such parameters into the Validation of Exoplanet Signals using a Probabilistic Algorithm (VESPA). These techniques and results serve as important tools for conducting candidate validation and follow-up observations for space-based missions such as the upcoming TESS mission since TESS’s large camera pixels resemble K2’s star-crowded fields.

Challenges in Discerning Atmospheric Composition in Directly Imaged Planets

Science.gov (United States)

Marley, Mark S.

2017-01-01

One of the justifications motivating efforts to detect and characterize young extrasolar giant planets has been to measure atmospheric composition for comparison with that of the primary star. If the enhancement of heavy elements in the atmospheres of extrasolar giant planets, like it is for their solar system analogs, is inversely proportional to mass, then it is likely that these worlds formed by core accretion. However in practice it has been very difficult to constrain metallicity because of the complex effect of clouds. Cloud opacity varies both vertically and, in some cases, horizontally through the atmosphere. Particle size and composition, both of which impact opacity, are difficult challenges both for forward modeling and retrieval studies. In my presentation I will discuss systematic efforts to improve cloud studies to enable more reliable determinations of atmospheric composition. These efforts are relevant both to discerning composition of directly imaged young planets from ground based telescopes and future space based missions, such as WFIRST and LUVOIR.

GEMINI PLANET IMAGER SPECTROSCOPY OF THE HR 8799 PLANETS c AND d

International Nuclear Information System (INIS)

Ingraham, Patrick; Macintosh, Bruce; Marley, Mark S.; Saumon, Didier; Marois, Christian; Dunn, Jennifer; Erikson, Darren; Barman, Travis; Bauman, Brian; Burrows, Adam; Chilcote, Jeffrey K.; Fitzgerald, Michael P.; De Rosa, Robert J.; Dillon, Daren; Gavel, Donald; Doyon, René; Goodsell, Stephen J.; Hartung, Markus; Hibon, Pascale; Graham, James R.

2014-01-01

During the first-light run of the Gemini Planet Imager we obtained K-band spectra of exoplanets HR 8799 c and d. Analysis of the spectra indicates that planet d may be warmer than planet c. Comparisons to recent patchy cloud models and previously obtained observations over multiple wavelengths confirm that thick clouds combined with horizontal variation in the cloud cover generally reproduce the planets' spectral energy distributions. When combined with the 3 to 4 μm photometric data points, the observations provide strong constraints on the atmospheric methane content for both planets. The data also provide further evidence that future modeling efforts must include cloud opacity, possibly including cloud holes, disequilibrium chemistry, and super-solar metallicity

Inside-out planet formation

International Nuclear Information System (INIS)

Chatterjee, Sourav; Tan, Jonathan C.

2014-01-01

The compact multi-transiting planet systems discovered by Kepler challenge planet formation theories. Formation in situ from disks with radial mass surface density, Σ, profiles similar to the minimum mass solar nebula but boosted in normalization by factors ≳ 10 has been suggested. We propose that a more natural way to create these planets in the inner disk is formation sequentially from the inside-out via creation of successive gravitationally unstable rings fed from a continuous stream of small (∼cm-m size) 'pebbles', drifting inward via gas drag. Pebbles collect at the pressure maximum associated with the transition from a magnetorotational instability (MRI)-inactive ('dead zone') region to an inner MRI-active zone. A pebble ring builds up until it either becomes gravitationally unstable to form an ∼1 M ⊕ planet directly or induces gradual planet formation via core accretion. The planet may undergo Type I migration into the active region, allowing a new pebble ring and planet to form behind it. Alternatively, if migration is inefficient, the planet may continue to accrete from the disk until it becomes massive enough to isolate itself from the accretion flow. A variety of densities may result depending on the relative importance of residual gas accretion as the planet approaches its isolation mass. The process can repeat with a new pebble ring gathering at the new pressure maximum associated with the retreating dead-zone boundary. Our simple analytical model for this scenario of inside-out planet formation yields planetary masses, relative mass scalings with orbital radius, and minimum orbital separations consistent with those seen by Kepler. It provides an explanation of how massive planets can form with tightly packed and well-aligned system architectures, starting from typical protoplanetary disk properties.

Scintillating fibre (SciFi) tracker

CERN Multimedia

Caraban Gonzalez, Noemi

2017-01-01

128 modules – containing 11 000 km of scintillating fibres – will make up the new SciFi tracker, which will replace the outer and inner trackers of the LHCb detector as part of the experiment’s major upgrade during Long Shutdown 2 (LS2)

Formation of S-type planets in close binaries: scattering induced tidal capture of circumbinary planets

Science.gov (United States)

Gong, Yan-Xiang; Ji, Jianghui

2018-05-01

Although several S-type and P-type planets in binary systems were discovered in past years, S-type planets have not yet been found in close binaries with an orbital separation not more than 5 au. Recent studies suggest that S-type planets in close binaries may be detected through high-accuracy observations. However, nowadays planet formation theories imply that it is difficult for S-type planets in close binaries systems to form in situ. In this work, we extensively perform numerical simulations to explore scenarios of planet-planet scattering among circumbinary planets and subsequent tidal capture in various binary configurations, to examine whether the mechanism can play a part in producing such kind of planets. Our results show that this mechanism is robust. The maximum capture probability is ˜10%, which can be comparable to the tidal capture probability of hot Jupiters in single star systems. The capture probability is related to binary configurations, where a smaller eccentricity or a low mass ratio of the binary will lead to a larger probability of capture, and vice versa. Furthermore, we find that S-type planets with retrograde orbits can be naturally produced via capture process. These planets on retrograde orbits can help us distinguish in situ formation and post-capture origin for S-type planet in close binaries systems. The forthcoming missions (PLATO) will provide the opportunity and feasibility to detect such planets. Our work provides several suggestions for selecting target binaries in search for S-type planets in the near future.

The Gemini Planet Imager Exoplanet Survey

Science.gov (United States)

Macintosh, Bruce

accurate and calibrated recovery of exoplanet spectra. We will produce a complete archive of all reduced GPI data products (supplementing the existing Gemini archive of raw data) for use by our collaboration, and release that archive to the public on an 18-month cycle. Most importantly, we will execute the GPI observations, initially through classical telescope visits, transitioning to remote and queue modes as our techniques are refined. As the first direct-imaging planet search with statistical depth comparable to Doppler planet detection and the first to probe into the snow line, the GPI Exoplanet Survey will provide strong constraints on paradigms for planet formation, completing the picture of the giant planet distribution throughout other solar systems, and also illuminating its evolution with stellar age and mass. We will deliver a catalog of detected exoplanets— the principal legacy of this campaign—released for follow-up by the astronomical community within 18 months of observation, as well as searchable archive of fully reduced images and detection limits for all stars surveyed. For each detected planet, we will produce estimated effective temperatures, luminosities, and semi-major axes: for a subset, high-SNR fiducial spectra, orbital eccentricities, and dynamical characterization through polarimetric imaging of attendant debris disks. GPI will complete final acceptance testing this month (May 2013) and is now ready to ship to Chile for first light in September 2013. The GPI survey will provide the best-yet view of the nature of wide-orbit planetary companions, informing our knowledge of solar system formation to guide future NASA planet hunting missions, while simultaneously offering a real- world program using the techniques - from integral field spectroscopy to advanced coronagraphy - that will someday be used to directly image Earthlike planets from space.

Auroral Data Analysis

Science.gov (United States)

1979-01-31

but expinds ’acordiohlike.’ (4) The height- integrated intensity ratio of the red (6300 A) to green (5577 A) emisions of atomic o\\)gen is a good... molecular ion: Analysis of two rocket experiments, Planet. Space Sci. 16, 737, 1968. Hays, P. B. and C. D. Anger, The influence of ground scattering on

TERRESTRIAL PLANET FORMATION DURING THE MIGRATION AND RESONANCE CROSSINGS OF THE GIANT PLANETS

International Nuclear Information System (INIS)

Lykawka, Patryk Sofia; Ito, Takashi

2013-01-01

The newly formed giant planets may have migrated and crossed a number of mutual mean motion resonances (MMRs) when smaller objects (embryos) were accreting to form the terrestrial planets in the planetesimal disk. We investigated the effects of the planetesimal-driven migration of Jupiter and Saturn, and the influence of their mutual 1:2 MMR crossing on terrestrial planet formation for the first time, by performing N-body simulations. These simulations considered distinct timescales of MMR crossing and planet migration. In total, 68 high-resolution simulation runs using 2000 disk planetesimals were performed, which was a significant improvement on previously published results. Even when the effects of the 1:2 MMR crossing and planet migration were included in the system, Venus and Earth analogs (considering both orbits and masses) successfully formed in several runs. In addition, we found that the orbits of planetesimals beyond a ∼ 1.5-2 AU were dynamically depleted by the strengthened sweeping secular resonances associated with Jupiter's and Saturn's more eccentric orbits (relative to the present day) during planet migration. However, this depletion did not prevent the formation of massive Mars analogs (planets with more than 1.5 times Mars's mass). Although late MMR crossings (at t > 30 Myr) could remove such planets, Mars-like small mass planets survived on overly excited orbits (high e and/or i), or were completely lost in these systems. We conclude that the orbital migration and crossing of the mutual 1:2 MMR of Jupiter and Saturn are unlikely to provide suitable orbital conditions for the formation of solar system terrestrial planets. This suggests that to explain Mars's small mass and the absence of other planets between Mars and Jupiter, the outer asteroid belt must have suffered a severe depletion due to interactions with Jupiter/Saturn, or by an alternative mechanism (e.g., rogue super-Earths)

Watching the Blue Planet from Space over Recent Decades: What's up for Science and Society?

Science.gov (United States)

Lindstrom, Eric J.

2015-01-01

Since the first photographs of “Earth Rise” taken by the Apollo astronauts in the 1960s galvanized the environmental movement, imaging of our planet from low Earth orbit has grown more sophisticated and diverse. Satellite and astronaut observations and imagery of the changing ocean still have the power to galvanize oceanographers and society. So what are some of the key ideas for oceanography and society that come out of out recent decades of ocean observation from space? Satellite oceanography has made fundamental contributions to our understanding and estimation of changing sea level, winds and storminess over the oceans, primary productivity of the seas, the role of the ocean in the water cycle, and the changes in the ocean known as ocean acidification. Some of these phenomena interact in complex ways and Mother Nature hides the future well. However, some things are clear. Sea level rise has been monitored from space for more than 20 years and now we have a more nuanced understanding of regional variation in sea level rise and the contributions of ocean thermal expansion and the melting of glaciers and ice sheets. Wind vectors at the ocean surface have been measured for more than 2 decades and provide evidence for shifts in wind patterns that help, for example, explain some of the regional variations in sea level rise. Chlorophyll-a has been estimated in a multi-decadal record of observations and is being used to describe the shifts and trends in ocean primary productivity. Sea surface temperature estimation from space has records going back to the 1970s and provides critical information for the interaction of the ocean with the atmosphere. Sea surface salinity has been measured from space only within the last decade and provides a novel new view of regional, seasonal, and inter-annual changes in the ocean related to precipitation, river run-off, and eddy transport. Potential changes in the Earth’s water cycle have a huge societal impact.

Results of the PERI survey of SciDAC applications

International Nuclear Information System (INIS)

Supinski, Bronis R de; Hollingworth, Jeffrey K; Moore, Shirley; Worley, Patrick H

2007-01-01

The Performance Engineering Research Institute (PERI) project focuses on achieving superior performance for Scientific Discovery through Advanced Computing (SciDAC) applications on leadership class machines through cutting-edge research in performance modeling and automated performance tuning. This focus requires coordinated activities to engage SciDAC application teams. The initial application engagement activity was a survey of these teams to determine their performance goals, the criticality of those goals, current performance of their applications, application characteristics relevant to performance and their plans for future optimization. Using a web-based questionnaire, PERI researchers have worked with application developers to provide this information for over twenty-five applications. This paper describes the initial analysis of the application characteristics and performance goals, as well as current and future application engagement activities driven by these results. While the survey was conducted primarily to meet PERI needs, the results represent a snapshot of the state of SciDAC code development and may be of use to the DOE community at large. Overall, the results show that SciDAC application teams are engaged in significant new code development, which will require flexible performance optimization techniques that can improve performance as the applications evolve

THE OCCURRENCE RATE OF EARTH ANALOG PLANETS ORBITING SUN-LIKE STARS

International Nuclear Information System (INIS)

Catanzarite, Joseph; Shao, Michael

2011-01-01

Kepler is a space telescope that searches Sun-like stars for planets. Its major goal is to determine η Earth , the fraction of Sun-like stars that have planets like Earth. When a planet 'transits' or moves in front of a star, Kepler can measure the concomitant dimming of the starlight. From analysis of the first four months of those measurements for over 150,000 stars, Kepler's Science Team has determined sizes, surface temperatures, orbit sizes, and periods for over a thousand new planet candidates. In this paper, we characterize the period probability distribution function of the super-Earth and Neptune planet candidates with periods up to 132 days, and find three distinct period regimes. For candidates with periods below 3 days, the density increases sharply with increasing period; for periods between 3 and 30 days, the density rises more gradually with increasing period, and for periods longer than 30 days, the density drops gradually with increasing period. We estimate that 1%-3% of stars like the Sun are expected to have Earth analog planets, based on the Kepler data release of 2011 February. This estimate of η Earth is based on extrapolation from a fiducial subsample of the Kepler planet candidates that we chose to be nominally 'complete' (i.e., no missed detections) to the realm of the Earth-like planets, by means of simple power-law models. The accuracy of the extrapolation will improve as more data from the Kepler mission are folded in. Accurate knowledge of η Earth is essential for the planning of future missions that will image and take spectra of Earth-like planets. Our result that Earths are relatively scarce means that a substantial effort will be needed to identify suitable target stars prior to these future missions.

DoD Information Security Program and Protection of Sensitive Compartmented Information (SCI)

Science.gov (United States)

2016-04-21

Sensitive Compartmented Information ( SCI ) References: See Enclosure 1 1. PURPOSE. In accordance with the authority in DoD Directive (DoDD...collateral, special access program, SCI , and controlled unclassified information (CUI) within an overarching DoD Information Security Program...use, and dissemination of SCI within the DoD pursuant to References (a), (c), and (e) and Executive Order 12333 (Reference (h)). 2

Violent Adolescent Planet Caught Infrared Handed

Science.gov (United States)

Trang, D.; Gaidos, E.

2010-01-01

The prevailing view of planet formation depicts accumulation of progressively larger objects, culminating in accretionary impacts between Moon- to Mars-sized protoplanets. Cosmochemists have found evidence in chondritic meteorites for such violent events, and the Moon is thought to have involved a huge impact between a Mars-sized object and the still-growing proto-Earth. Now we may have evidence for a large impact during planet formation around another star. Carey Lisse (Applied Physics Lab of the Johns Hopkins University, Baltimore) and colleagues from the Space Telescope Science Institute (Baltimore), the University of Cambridge (UK), the Open University (Milton Keyes, UK), the University of Georgia (Athens, GA), Jet Propulsion Lab (Pasadena, CA), and the University of Rochester (New York) analyzed infrared spectra obtained by the Spitzer Space Telescope. They found a prominent peak in the spectrum at 9.3 micrometers, and two smaller ones at slightly lower and higher wavelengths. These peaks are consistent with the presence of SiO gas, a product expected to be produced by a highly energetic impact. The spectral measurements also allowed Lisse and his colleagues to estimate the size of the dust and they found that there is an abundance of micrometer-sized dust grains. This argues for a fresh source of fine material during the past 0.1 million years. That source may have been an impact between two protoplanets surrounding this young star.

Optimized Strategies for Detecting Extrasolar Space Weather

Science.gov (United States)

Hallinan, Gregg

2018-06-01

Fully understanding the implications of space weather for the young solar system, as well as the wider population of planet-hosting stars, requires remote sensing of space weather in other stellar systems. Solar coronal mass ejections can be accompanied by bright radio bursts at low frequencies (typically measurement of the magnetic field strength of the planet, informing on whether the atmosphere of the planet can survive the intense magnetic activity of its host star. However, both stellar and planetary radio emission are highly variable and optimal strategies for detection of these emissions requires the capability to monitor 1000s of nearby stellar/planetary systems simultaneously. I will discuss optimized strategies for both ground and space-based experiments to take advantage of the highly variable nature of the radio emissions powered by extrasolar space weather to enable detection of stellar CMEs and planetary magnetospheres.

A comprehensive mission to planet Earth: Woods Hole Space Science and Applications Advisory Committee Planning Workshop

Science.gov (United States)

1991-01-01

The NASA program Mission to Planet Earth (MTPE) is described in this set of visuals presented in Massachusetts on July 29, 1991. The problem presented in this document is that the earth system is changing and that human activity accelerates the rate of change resulting in increased greenhouse gases, decreasing levels of stratospheric ozone, acid rain, deforestation, decreasing biodiversity, and overpopulation. Various national and international organizations are coordinating global change research. The complementary space observations for this activity are sun-synchronous polar orbits, low-inclination, low altitude orbits, geostationary orbits, and ground measurements. The Geostationary Earth Observatory is the major proposed mission of MTPE. Other proposed missions are EOS Synthetic Aperture Radar, ARISTOTELES Magnetic Field Experiment, and the Global Topography Mission. Use of the NASA DC-8 aircraft is outlined as carrying out the Airborne Science and Applications Program. Approved Earth Probes Program include the Total Ozone Mapping Spectrometer (TOMS). Other packages for earth observation are described.

A Search for Lost Planets in the Kepler Multi-Planet Systems and the Discovery of the Long-Period, Neptune-Sized Exoplanet Kepler-150 f

Science.gov (United States)

Schmitt, Joseph R.; Jenkins, Jon M.; Fischer, Debra A.

2017-01-01

The vast majority of the 4700 confirmed planets and planet candidates discovered by the Kepler space telescope were first found by the Kepler pipeline. In the pipeline, after a transit signal is found, all data points associated with those transits are removed, creating a Swiss cheese-like light curve full of holes, which is then used for subsequent transit searches. These holes could render an additional planet undetectable (or lost). We examine a sample of 114 stars with 3+ confirmed planets to see the effect that this Swiss cheesing may have. A simulation determined that the probability that a transiting planet is lost due to the transit masking is low, but non-neglible, reaching a plateau at approximately 3.3% lost in the period range of P = 400 - 500 days. We then model the transits in all quarters of each star and subtract out the transit signals, restoring the in-transit data points, and use the Kepler pipeline to search the transit-subtracted (i.e., transit-cleaned) light curves. However, the pipeline did not discover any credible new transit signals. This demonstrates the validity and robustness of the Kepler pipelines choice to use transit masking over transit subtraction. However, a follow-up visual search through all the transit-subtracted data, which allows for easier visual identification of new transits, revealed the existence of a new, Neptune-sized exoplanet. Kepler-150 f (P = 637.2 days, RP = 3.86 R earth) is confirmed using a combination of false positive probability analysis, transit duration analysis, and the planet multiplicity argument.

A SEARCH FOR LOST PLANETS IN THE KEPLER MULTI-PLANET SYSTEMS AND THE DISCOVERY OF A LONG PERIOD, NEPTUNE-SIZED EXOPLANET KEPLER-150 F.

Science.gov (United States)

Schmitt, Joseph R; Jenkins, Jon M; Fischer, Debra A

2017-04-01

The vast majority of the 4700 confirmed planets and planet candidates discovered by the Kepler space telescope were first found by the Kepler pipeline. In the pipeline, after a transit signal is found, all data points associated with those transits are removed, creating a "Swiss cheese"-like light curve full of holes, which is then used for subsequent transit searches. These holes could render an additional planet undetectable (or "lost"). We examine a sample of 114 stars with 3+ confirmed planets to see the effect that this "Swiss cheesing" may have. A simulation determined that the probability that a transiting planet is lost due to the transit masking is low, but non-neglible, reaching a plateau at ~3.3% lost in the period range of P = 400 - 500 days. We then model the transits in all quarters of each star and subtract out the transit signals, restoring the in-transit data points, and use the Kepler pipeline to search the transit-subtracted (i.e., transit-cleaned) light curves. However, the pipeline did not discover any credible new transit signals. This demonstrates the validity and robustness of the Kepler pipeline's choice to use transit masking over transit subtraction. However, a follow-up visual search through all the transit-subtracted data, which allows for easier visual identification of new transits, revealed the existence of a new, Neptune-sized exoplanet. Kepler-150 f ( P = 637.2 days, R P = 3.86 R ⊕ ) is confirmed using a combination of false positive probability analysis, transit duration analysis, and the planet multiplicity argument.

Sci-Hub: What Librarians Should Know and Do about Article Piracy.

Science.gov (United States)

Hoy, Matthew B

2017-01-01

The high cost of journal articles has driven many researchers to turn to a new way of getting access: "pirate" article sites. Sci-Hub, the largest and best known of these sites, currently offers instant access to more than 58 million journal articles. Users attracted by the ease of use and breadth of the collection may not realize that these articles are often obtained using stolen credentials and downloading them may be illegal. This article will briefly describe Sci-Hub and how it works, the legal and ethical issues it raises, and the problems it may cause for librarians. Librarians should be aware of Sci-Hub and the ways it may change their patrons' expectations. They should also understand the risks Sci-Hub can pose to their patrons and their institutions.

Taxonomy of the extrasolar planet.

Science.gov (United States)

Plávalová, Eva

2012-04-01

When a star is described as a spectral class G2V, we know that the star is similar to our Sun. We know its approximate mass, temperature, age, and size. When working with an extrasolar planet database, it is very useful to have a taxonomy scale (classification) such as, for example, the Harvard classification for stars. The taxonomy has to be easily interpreted and present the most relevant information about extrasolar planets. I propose an extrasolar planet taxonomy scale with four parameters. The first parameter concerns the mass of an extrasolar planet in the form of units of the mass of other known planets, where M represents the mass of Mercury, E that of Earth, N Neptune, and J Jupiter. The second parameter is the planet's distance from its parent star (semimajor axis) described in a logarithm with base 10. The third parameter is the mean Dyson temperature of the extrasolar planet, for which I established four main temperature classes: F represents the Freezing class, W the Water class, G the Gaseous class, and R the Roasters class. I devised one additional class, however: P, the Pulsar class, which concerns extrasolar planets orbiting pulsar stars. The fourth parameter is eccentricity. If the attributes of the surface of the extrasolar planet are known, we are able to establish this additional parameter where t represents a terrestrial planet, g a gaseous planet, and i an ice planet. According to this taxonomy scale, for example, Earth is 1E0W0t, Neptune is 1N1.5F0i, and extrasolar planet 55 Cnc e is 9E-1.8R1.

Holy sci-fi! where science fiction and religion intersect

CERN Document Server

Nahin, Paul J

2014-01-01

Can a computer have a soul? Are religion and science mutually exclusive? Is there really such a thing as free will? If you could time travel to visit Jesus, would you (and should you)? For hundreds of years, philosophers, scientists, and science fiction writers have pondered these questions and many more. In Holy Sci-Fi!, popular writer Paul Nahin explores the fertile and sometimes uneasy relationship between science fiction and religion. With a scope spanning the history of religion, philosophy, and literature, Nahin follows religious themes in science fiction from Feynman to Foucault, and from Asimov to Aristotle. An intriguing journey through popular and well-loved books and stories, Holy Sci-Fi! shows how sci-fi has informed humanity's attitudes towards our faiths, our future, and ourselves.

Physics Motivations of SciBooNE

International Nuclear Information System (INIS)

Hiraide, K.

2007-01-01

SciBooNE is a new experiment for measuring neutrino-nucleus cross sections around one GeV region, which is important for the interpretaion of neutrino oscillation experiments. Physics motivations of the experiment are described here

The Hunt for Planet X New Worlds and the Fate of Pluto

CERN Document Server

Schilling, Govert

2009-01-01

"The Hunt for Planet X is a fascinating tale by one of the world's premier astronomy writers. Govert Schilling is not only scrupulously accurate, he writes beautifully as well." Stephen P. Maran, Author of "Astronomy for Dummies" and Press Officer, American Astronomical Society "The Hunt for Planet X is an adventure story or, more accurately, a series of adventure stories. Schilling tells them well, capturing both the science and the people involved. It starts with the classics: Uranus, Neptune and Pluto; and moves all over the solar system as ground-based astronomers and space scientists pour over measurements and observations to try to understand the worlds around us. Current debates about the Pioneer Anomaly and the definition of what is a planet make the book current as well as a good history." Dr. Louis Friedman, Executive Director, The Planetary Society "This exciting tale of the centuries-old search for new planets in the solar system reads like a thriller. It is an adventure packed with fierce competi...

Observed properties of extrasolar planets.

Science.gov (United States)

Howard, Andrew W

2013-05-03

Observational surveys for extrasolar planets probe the diverse outcomes of planet formation and evolution. These surveys measure the frequency of planets with different masses, sizes, orbital characteristics, and host star properties. Small planets between the sizes of Earth and Neptune substantially outnumber Jupiter-sized planets. The survey measurements support the core accretion model, in which planets form by the accumulation of solids and then gas in protoplanetary disks. The diversity of exoplanetary characteristics demonstrates that most of the gross features of the solar system are one outcome in a continuum of possibilities. The most common class of planetary system detectable today consists of one or more planets approximately one to three times Earth's size orbiting within a fraction of the Earth-Sun distance.

Space and Planetary Resources

Science.gov (United States)

Abbud-Madrid, Angel

2018-02-01

The space and multitude of celestial bodies surrounding Earth hold a vast wealth of resources for a variety of space and terrestrial applications. The unlimited solar energy, vacuum, and low gravity in space, as well as the minerals, metals, water, atmospheric gases, and volatile elements on the Moon, asteroids, comets, and the inner and outer planets of the Solar System and their moons, constitute potential valuable resources for robotic and human space missions and for future use in our own planet. In the short term, these resources could be transformed into useful materials at the site where they are found to extend mission duration and to reduce the costly dependence from materials sent from Earth. Making propellants and human consumables from local resources can significantly reduce mission mass and cost, enabling longer stays and fueling transportation systems for use within and beyond the planetary surface. Use of finely grained soils and rocks can serve for habitat construction, radiation protection, solar cell fabrication, and food growth. The same material could also be used to develop repair and replacement capabilities using advanced manufacturing technologies. Following similar mining practices utilized for centuries on Earth, identifying, extracting, and utilizing extraterrestrial resources will enable further space exploration, while increasing commercial activities beyond our planet. In the long term, planetary resources and solar energy could also be brought to Earth if obtaining these resources locally prove to be no longer economically or environmentally acceptable. Throughout human history, resources have been the driving force for the exploration and settling of our planet. Similarly, extraterrestrial resources will make space the next destination in the quest for further exploration and expansion of our species. However, just like on Earth, not all challenges are scientific and technological. As private companies start working toward

Ablated tektite from the central Indian Ocean

Digital Repository Service at National Institute of Oceanography (India)

Glass, B.P.; Chapman, D.R.; ShyamPrasad, M.

stream_size 100 stream_content_type text/plain stream_name Meteor_Planet_Sci_31_365.pdf.txt stream_source_info Meteor_Planet_Sci_31_365.pdf.txt Content-Encoding ISO-8859-1 Content-Type text/plain; charset=ISO-8859-1 1996...

New occurrences of Australasian microtektites in the Central Indian Basin

Digital Repository Service at National Institute of Oceanography (India)

ShyamPrasad, M.

stream_size 4 stream_content_type text/plain stream_name Meteor_Planet_Sci_29_66.pdf.txt stream_source_info Meteor_Planet_Sci_29_66.pdf.txt Content-Encoding ISO-8859-1 Content-Type text/plain; charset=ISO-8859-1 ...

Histories of terrestrial planets

International Nuclear Information System (INIS)

Benes, K.

1981-01-01

The uneven historical development of terrestrial planets - Mercury, Venus, Earth, Moon and Mars - is probably due to the differences in their size, weight and rotational dynamics in association with the internal planet structure, their distance from the Sun, etc. A systematic study of extraterrestrial planets showed that the time span of internal activity was not the same for all bodies. It is assumed that the initial history of all terrestrial planets was marked with catastrophic events connected with the overall dynamic development of the solar system. In view of the fact that the cores of small terrestrial bodies cooled quicker, their geological development almost stagnated after two or three thousand million years. This is what probably happened to the Mercury and the Moon as well as the Mars. Therefore, traces of previous catastrophic events were preserved on the surface of the planets. On the other hand, the Earth is the most metamorphosed terrestrial planet and compared to the other planets appears to be atypical. Its biosphere is significantly developed as well as the other shell components, its hydrosphere and atmosphere, and its crust is considerably differentiated. (J.P.)

SECULAR BEHAVIOR OF EXOPLANETS: SELF-CONSISTENCY AND COMPARISONS WITH THE PLANET-PLANET SCATTERING HYPOTHESIS

Energy Technology Data Exchange (ETDEWEB)

Timpe, Miles; Barnes, Rory [Astronomy Department, University of Washington, Box 351580, Seattle, WA 98195 (United States); Kopparapu, Ravikumar; Raymond, Sean N. [Virtual Planetary Laboratory, Seattle, WA 98195 (United States); Greenberg, Richard [Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721 (United States); Gorelick, Noel, E-mail: apskier@astro.washington.edu [Google, Inc., 1600 Amphitheater Parkway, Mountain View, CA 94043 (United States)

2013-09-15

If mutual gravitational scattering among exoplanets occurs, then it may produce unique orbital properties. For example, two-planet systems that lie near the boundary between circulation and libration of their periapses could result if planet-planet scattering ejected a former third planet quickly, leaving one planet on an eccentric orbit and the other on a circular orbit. We first improve upon previous work that examined the apsidal behavior of known multiplanet systems by doubling the sample size and including observational uncertainties. This analysis recovers previous results that demonstrated that many systems lay on the apsidal boundary between libration and circulation. We then performed over 12,000 three-dimensional N-body simulations of hypothetical three-body systems that are unstable, but stabilize to two-body systems after an ejection. Using these synthetic two-planet systems, we test the planet-planet scattering hypothesis by comparing their apsidal behavior, over a range of viewing angles, to that of the observed systems and find that they are statistically consistent regardless of the multiplicity of the observed systems. Finally, we combine our results with previous studies to show that, from the sampled cases, the most likely planetary mass function prior to planet-planet scattering follows a power law with index -1.1. We find that this pre-scattering mass function predicts a mutual inclination frequency distribution that follows an exponential function with an index between -0.06 and -0.1.

Meteoric Impact and Ion Density Calculation in the Nighttime ...

Indian Academy of Sciences (India)

Bhavin

2013-11-08

Nov 8, 2013 ... Pandya, B. M., and S. A. Haider (2012), Meteor impact perturbation in the lower ionosphere of Mars: MGS observations,. Planet. Space Sci., 63, 105-109, doi: 10.1016/j.pss.2011.09.013. Page 6. Pandya, B. M., and S. A. Haider (2012), Meteor impact perturbation in the lower ionosphere of Mars: MGS ...

A SciCode web site: building bridges between owners and users

Energy Technology Data Exchange (ETDEWEB)

Gaver, C. [Atomic Energy of Canada Ltd., Mississauga, Ontario (Canada)

2000-07-01

Web technology is a tool that is gaining in popularity. Properly used, it is a powerful tool that has tremendous potential for providing better communication. It can also be effective as a training tool, an information-sharing tool, and as a means of simplifying work load, and facilitating compliance with Company procedures. The issue is one of communication. The challenge facing many large or geographically-distributed companies is how to communicate information to their staff and to their customers. Procedures overseeing quality-assurance programs and commitment to ensuring the quality of products need to be communicated to customers. Equally important is customer feedback. This information from users becomes the kernel for future product development. The issue is even more important when speaking of scientific analysis computer programs (SciCodes). Regular ongoing communication between Primary Holders and End Users is essential in the development and use of SciCodes. Without this communication, quality assurance is at risk. Quality assurance processes are an integral part in developing any SciCode. End Users also have a role to play. Primary Holders keep End Users informed of improvements or new releases. End Users must ensure they act on this information. Equally important, End Users must communicate problems or suggestions to the Primary Holder to remedy or incorporate in new releases. In other words, quality assurance processes become most effective when both Primary Holder and End Users are involved. This requires communication. Web technology offers AECL a means of providing regular, ongoing communication between its scientific-code (SciCode) Primary Holders-Owner Branches and the End Users of these codes within and outside the Company. Using the experience we have gained by developing the Y2K SciCode Web sites, setting up online documentation systems, and incorporating lessons learned from the Y2K project we have developed a model that is geared to

A SciCode web site: building bridges between owners and users

International Nuclear Information System (INIS)

Gaver, C.

2000-01-01

Web technology is a tool that is gaining in popularity. Properly used, it is a powerful tool that has tremendous potential for providing better communication. It can also be effective as a training tool, an information-sharing tool, and as a means of simplifying work load, and facilitating compliance with Company procedures. The issue is one of communication. The challenge facing many large or geographically-distributed companies is how to communicate information to their staff and to their customers. Procedures overseeing quality-assurance programs and commitment to ensuring the quality of products need to be communicated to customers. Equally important is customer feedback. This information from users becomes the kernel for future product development. The issue is even more important when speaking of scientific analysis computer programs (SciCodes). Regular ongoing communication between Primary Holders and End Users is essential in the development and use of SciCodes. Without this communication, quality assurance is at risk. Quality assurance processes are an integral part in developing any SciCode. End Users also have a role to play. Primary Holders keep End Users informed of improvements or new releases. End Users must ensure they act on this information. Equally important, End Users must communicate problems or suggestions to the Primary Holder to remedy or incorporate in new releases. In other words, quality assurance processes become most effective when both Primary Holder and End Users are involved. This requires communication. Web technology offers AECL a means of providing regular, ongoing communication between its scientific-code (SciCode) Primary Holders-Owner Branches and the End Users of these codes within and outside the Company. Using the experience we have gained by developing the Y2K SciCode Web sites, setting up online documentation systems, and incorporating lessons learned from the Y2K project we have developed a model that is geared to

Science and Development Network (SciDev.net) - Phase IV | IDRC ...

International Development Research Centre (IDRC) Digital Library (Canada)

SciDev.net was set up in 2001 as an organization dedicated to providing reliable and authoritative information about science and technology (S&T) for the developing world. SciDev.Net does this primarily through a free-access website, but also by organizing training workshops and other activities in the developing world.

THE DYNAMICS OF THREE-PLANET SYSTEMS: AN APPROACH FROM A DYNAMICAL SYSTEM

International Nuclear Information System (INIS)

Shikita, Bungo; Yamada, Shoichi; Koyama, Hiroko

2010-01-01

We study in detail the motions of three planets interacting with each other under the influence of a central star. It is known that the system with more than two planets becomes unstable after remaining quasi-stable for long times, leading to highly eccentric orbital motions or ejections of some of the planets. In this paper, we are concerned with the underlying physics for this quasi-stability as well as the subsequent instability and advocate the so-called stagnant motion in the phase space, which has been explored in the field of a dynamical system. We employ the Lyapunov exponent, the power spectra of orbital elements, and the distribution of the durations of quasi-stable motions to analyze the phase-space structure of the three-planet system, the simplest and hopefully representative one that shows the instability. We find from the Lyapunov exponent that the system is almost non-chaotic in the initial quasi-stable state whereas it becomes intermittently chaotic thereafter. The non-chaotic motions produce the horizontal dense band in the action-angle plot whereas the voids correspond to the chaotic motions. We obtain power laws for the power spectra of orbital eccentricities. Power-law distributions are also found for the durations of quasi-stable states. With all these results combined together, we may reach the following picture: the phase space consists of the so-called KAM tori surrounded by satellite tori and imbedded in the chaotic sea. The satellite tori have a self-similar distribution and are responsible for the scale-free power-law distributions of the duration times. The system is trapped around one of the KAM torus and the satellites for a long time (the stagnant motion) and moves to another KAM torus with its own satellites from time to time, corresponding to the intermittent chaotic behaviors.

www.elearnSCI.org: a global educational initiative of ISCoS.

Science.gov (United States)

Chhabra, H S; Harvey, L A; Muldoon, S; Chaudhary, S; Arora, M; Brown, D J; Biering-Sorensen, F; Wyndaele, J J; Charlifue, S; Horsewell, J; Ducharme, S; Green, D; Simpson, D; Glinsky, J; Weerts, E; Upadhyay, N; Aito, S; Wing, P; Katoh, S; Kovindha, A; Krassioukov, A; Weeks, C; Srikumar, V; Reeves, R; Siriwardane, C; Hasnan, N; Kalke, Y B; Lanig, I

2013-03-01

To develop a web-based educational resource for health professionals responsible for the management of spinal cord injury (SCI). The resource:www.elearnSCI.org is comprised of seven learning modules, each subdivided into various submodules. Six of the seven modules address the educational needs of all disciplines involved in comprehensive SCI management. The seventh module addresses prevention of SCI. Each submodule includes an overview, activities, self-assessment questions and references. Three hundred and thirty-two experts from The International Spinal Cord Society (ISCoS) and various affiliated societies from 36 countries were involved in developing the resource through 28 subcommittees. The content of each submodule was reviewed and approved by the Education and Scientific Committees of ISCoS and finally by an Editorial Committee of 23 experts. The content of the learning modules is relevant to students and to new as well as experienced SCI healthcare professionals. The content is applicable globally, has received consumer input and is available at no cost. The material is presented on a website underpinned by a sophisticated content-management system, which allows easy maintenance and ready update of all the content. The resource conforms to key principles of e-learning, including appropriateness of curriculum, engagement of learners, innovative approaches, effective learning, ease of use, inclusion, assessment, coherence, consistency, transparency, cost effectiveness and feedback. www.elearnSCI.org provides a cost effective way of training healthcare professionals that goes beyond the textbook and traditional face-to-face teaching.

Planets in Binary Star Systems

CERN Document Server

Haghighipour, Nader

2010-01-01

The discovery of extrasolar planets over the past decade has had major impacts on our understanding of the formation and dynamical evolution of planetary systems. There are features and characteristics unseen in our solar system and unexplainable by the current theories of planet formation and dynamics. Among these new surprises is the discovery of planets in binary and multiple-star systems. The discovery of such "binary-planetary" systems has confronted astrodynamicists with many new challenges, and has led them to re-examine the theories of planet formation and dynamics. Among these challenges are: How are planets formed in binary star systems? What would be the notion of habitability in such systems? Under what conditions can binary star systems have habitable planets? How will volatiles necessary for life appear on such planets? This volume seeks to gather the current research in the area of planets in binary and multistar systems and to familiarize readers with its associated theoretical and observation...

Habitable zone limits for dry planets.

Science.gov (United States)

Abe, Yutaka; Abe-Ouchi, Ayako; Sleep, Norman H; Zahnle, Kevin J

2011-06-01

Most discussion of habitable planets has focused on Earth-like planets with globally abundant liquid water. For an "aqua planet" like Earth, the surface freezes if far from its sun, and the water vapor greenhouse effect runs away if too close. Here we show that "land planets" (desert worlds with limited surface water) have wider habitable zones than aqua planets. For planets at the inner edge of the habitable zone, a land planet has two advantages over an aqua planet: (i) the tropics can emit longwave radiation at rates above the traditional runaway limit because the air is unsaturated and (ii) the dry air creates a dry stratosphere that limits hydrogen escape. At the outer limits of the habitable zone, the land planet better resists global freezing because there is less water for clouds, snow, and ice. Here we describe a series of numerical experiments using a simple three-dimensional global climate model for Earth-sized planets. Other things (CO(2), rotation rate, surface pressure) unchanged, we found that liquid water remains stable at the poles of a low-obliquity land planet until net insolation exceeds 415 W/m(2) (170% that of modern Earth), compared to 330 W/m(2) (135%) for the aqua planet. At the outer limits, we found that a low-obliquity land planet freezes at 77%, while the aqua planet freezes at 90%. High-obliquity land and aqua planets freeze at 58% and 72%, respectively, with the poles offering the last refuge. We show that it is possible that, as the Sun brightens, an aqua planet like Earth can lose most of its hydrogen and become a land planet without first passing through a sterilizing runaway greenhouse. It is possible that Venus was a habitable land planet as recently as 1 billion years ago.

TESTING IN SITU ASSEMBLY WITH THE KEPLER PLANET CANDIDATE SAMPLE

Energy Technology Data Exchange (ETDEWEB)

Hansen, Brad M. S. [Department of Physics and Astronomy and Institute of Geophysics and Planetary Physics, University of California Los Angeles, Los Angeles, CA 90095 (United States); Murray, Norm, E-mail: hansen@astro.ucla.edu, E-mail: murray@cita.utoronto.ca [Canadian Institute for Theoretical Astrophysics, 60 St. George Street, University of Toronto, Toronto, ON M5S 3H8 (Canada)

2013-09-20

We present a Monte Carlo model for the structure of low-mass (total mass <25 M{sub ⊕}) planetary systems that form by the in situ gravitational assembly of planetary embryos into final planets. Our model includes distributions of mass, eccentricity, inclination, and period spacing that are based on the simulation of a disk of 20 M{sub ⊕}, forming planets around a solar-mass star, and assuming a power-law surface density distribution that drops with distance a as ∝ a {sup –1.5}. The output of the Monte Carlo model is then subjected to the selection effects that mimic the observations of a transiting planet search such as that performed by the Kepler satellite. The resulting comparison of the output to the properties of the observed sample yields an encouraging agreement in terms of the relative frequencies of multiple-planet systems and the distribution of the mutual inclinations when moderate tidal circularization is taken into account. The broad features of the period distribution and radius distribution can also be matched within this framework, although the model underpredicts the distribution of small period ratios. This likely indicates that some dissipation is still required in the formation process. The most striking deviation between the model and observations is in the ratio of single to multiple systems in that there are roughly 50% more single-planet candidates observed than are produced in any model population. This suggests that some systems must suffer additional attrition to reduce the number of planets or increase the range of inclinations.

The Kepler Mission: A Search for Terrestrial Planets - Development Status

Science.gov (United States)

Koch, David; Borucki, W.; Mayer, D.; Caldwell, D.; Jenkens, J.; Dunham, E.; Geary, J.; Bachtell, E.; Deininger, W.; Philbrick, R.

2003-01-01

We have embarked on a mission to detect terrestrial planets. The space mission has been optimized to search for earth-size planets (0.5 to 10 earth masses) in the habitable zone (HZ) of solar-like stars. Given this design, the mission will necessarily be capable of not only detecting Earth analogs, but a wide range of planetary types and characteristics ranging from Mercury-size objects with orbital periods of days to gas-giants in decade long orbits that have undeniable signatures even with only one transit detected. The mission is designed to survey the full range of spectral-type dwarf stars. The approach is to detect the periodic signal of transiting planets. Three or more transits of a star exceeding a combined threshold of eight sigma with a statistically consistent period, brightness change and duration provide a rigorous method of detection. From the relative brightness change the planet size can be calculated. From the period the orbital size can be calculated and its location relative to the HZ determined. Presented here are: the mission goals, the top level system design requirements derived from these goals that drive the flight system design, a number of the trades that have lead to the mission concept, expected photometric performance dependence on stellar brightness and spectral type based on the system 'noise tree' analysis. Updated estimates are presented of the numbers of detectable planets versus size, orbit, stellar spectral type and distances based on a planet frequency hypothesis. The current project schedule and organization are given.

Some fixed point theorems in fuzzy reflexive Banach spaces

International Nuclear Information System (INIS)

Sadeqi, I.; Solaty kia, F.

2009-01-01

In this paper, we first show that there are some gaps in the fixed point theorems for fuzzy non-expansive mappings which are proved by Bag and Samanta, in [Bag T, Samanta SK. Fixed point theorems on fuzzy normed linear spaces. Inf Sci 2006;176:2910-31; Bag T, Samanta SK. Some fixed point theorems in fuzzy normed linear spaces. Inform Sci 2007;177(3):3271-89]. By introducing the notion of fuzzy and α- fuzzy reflexive Banach spaces, we obtain some results which help us to establish the correct version of fuzzy fixed point theorems. Second, by applying Theorem 3.3 of Sadeqi and Solati kia [Sadeqi I, Solati kia F. Fuzzy normed linear space and it's topological structure. Chaos, Solitons and Fractals, in press] which says that any fuzzy normed linear space is also a topological vector space, we show that all topological version of fixed point theorems do hold in fuzzy normed linear spaces.

N-body simulations of planet formation: understanding exoplanet system architectures

Science.gov (United States)

Coleman, Gavin; Nelson, Richard

2015-12-01

Observations have demonstrated the existence of a significant population of compact systems comprised of super-Earths and Neptune-mass planets, and a population of gas giants that appear to occur primarily in either short-period (100 days) orbits. The broad diversity of system architectures raises the question of whether or not the same formation processes operating in standard disc models can explain these planets, or if different scenarios are required instead to explain the widely differing architectures. To explore this issue, we present the results from a comprehensive suite of N-body simulations of planetary system formation that include the following physical processes: gravitational interactions and collisions between planetary embryos and planetesimals; type I and II migration; gas accretion onto planetary cores; self-consistent viscous disc evolution and disc removal through photo-evaporation. Our results indicate that the formation and survival of compact systems of super-Earths and Neptune-mass planets occur commonly in disc models where a simple prescription for the disc viscosity is assumed, but such models never lead to the formation and survival of gas giant planets due to migration into the star. Inspired in part by the ALMA observations of HL Tau, and by MHD simulations that display the formation of long-lived zonal flows, we have explored the consequences of assuming that the disc viscosity varies in both time and space. We find that the radial structuring of the disc leads to conditions in which systems of giant planets are able to form and survive. Furthermore, these giants generally occupy those regions of the mass-period diagram that are densely populated by the observed gas giants, suggesting that the planet traps generated by radial structuring of protoplanetary discs may be a necessary ingredient for forming giant planets.

Tilting Saturn without Tilting Jupiter: Constraints on Giant Planet Migration

Science.gov (United States)

Brasser, R.; Lee, Man Hoi

2015-11-01

The migration and encounter histories of the giant planets in our solar system can be constrained by the obliquities of Jupiter and Saturn. We have performed secular simulations with imposed migration and N-body simulations with planetesimals to study the expected obliquity distribution of migrating planets with initial conditions resembling those of the smooth migration model, the resonant Nice model and two models with five giant planets initially in resonance (one compact and one loose configuration). For smooth migration, the secular spin-orbit resonance mechanism can tilt Saturn’s spin axis to the current obliquity if the product of the migration timescale and the orbital inclinations is sufficiently large (exceeding 30 Myr deg). For the resonant Nice model with imposed migration, it is difficult to reproduce today’s obliquity values, because the compactness of the initial system raises the frequency that tilts Saturn above the spin precession frequency of Jupiter, causing a Jupiter spin-orbit resonance crossing. Migration timescales sufficiently long to tilt Saturn generally suffice to tilt Jupiter more than is observed. The full N-body simulations tell a somewhat different story, with Jupiter generally being tilted as often as Saturn, but on average having a higher obliquity. The main obstacle is the final orbital spacing of the giant planets, coupled with the tail of Neptune’s migration. The resonant Nice case is barely able to simultaneously reproduce the orbital and spin properties of the giant planets, with a probability ˜ 0.15%. The loose five planet model is unable to match all our constraints (probability <0.08%). The compact five planet model has the highest chance of matching the orbital and obliquity constraints simultaneously (probability ˜0.3%).

Kepler planet-detection mission

DEFF Research Database (Denmark)

Borucki...[], William J.; Koch, David; Buchhave, Lars C. Astrup

2010-01-01

The Kepler mission was designed to determine the frequency of Earth-sized planets in and near the habitable zone of Sun-like stars. The habitable zone is the region where planetary temperatures are suitable for water to exist on a planet’s surface. During the first 6 weeks of observations, Kepler...... is one of the lowest-density planets (~0.17 gram per cubic centimeter) yet detected. Kepler-5b, -6b, and -8b confirm the existence of planets with densities lower than those predicted for gas giant planets....

Alpha Elements' Effects on Planet Formation and the Hunt for Extragalactic Planets

Science.gov (United States)

Penny, Matthew; Rodriguez, Joseph E.; Beatty, Thomas; Zhou, George

2018-01-01

A star's likelihood of hosting a giant planet is well known to be strongly dependent on metallicity. However, little is known about what elements cause this correlation (e.g. bulk metals, iron, or alpha elements such as silicon and oxygen). This is likely because most planet searches target stars in the Galactic disk, and due to Galactic chemical evolution, alpha element abundances are themselves correlated with metallicity within a population. We investigate the feasibility of simultaneous transiting planet search towards the alpha-poor Sagittarius dwarf galaxy and alpha-rich Galactic bulge in a single field of view of DECam, that would enable a comparative study of planet frequency over an [alpha/Fe] baseline of ~0.4 dex. We show that a modestly sized survey could detect planet candidates in both populations, but that false positive rejection in Sgr Dwarf may be prohibitively expensive. Conversely, two-filter survey observations alone would be sufficient to rule out a large fraction of bulge false positives, enabling statistical validation of candidates with a modest follow-up investment. Although over a shorter [alpha/Fe] baseline, this survey would provide a test of whether it is alpha or iron that causes the planet metallicity correlation.

The SCI Exercise Self-Efficacy Scale (ESES: development and psychometric properties

Directory of Open Access Journals (Sweden)

Ho Pei-Shu

2007-08-01

Full Text Available Abstract Background Rising prevalence of secondary conditions among persons with spinal cord injury (SCI has focused recent attention to potential health promotion programs designed to reduce such adverse health conditions. A healthy lifestyle for people with SCI, including and specifically, the adoption of a vigorous exercise routine, has been shown to produce an array of health benefits, prompting many providers to recommend the implementation of such activity to those with SCI. Successfully adopting such an exercise regimen however, requires confidence in one's ability to engage in exercise or exercise self-efficacy. Exercise self-efficacy has not been assessed adequately for people with SCI due to a lack of validated and reliable scales, despite self efficacy's status as one of the most widely researched concepts and despite its broad application in health promotion studies. Exercise self efficacy supporting interventions for people with SCI are only meaningful if appropriate measurement tools exist. The objective of our study was to develop a psychometrically sound exercise self-efficacy self-report measure for people with SCI. Methods Based on literature reviews, expert comments and cognitive testing, 10 items were included and made up the 4-point Likert SCI Exercise Self-Efficacy Scale (ESES in its current form. The ESES was administered as part of the first wave of a nationwide survey (n = 368 on exercise behavior and was also tested separately for validity in four groups of individuals with SCI. Reliability and validity testing was performed using SPSS 12.0. Results Cronbach's alpha was .9269 for the ESES. High internal consistency was confirmed in split-half (EQ Length Spearman Brown = .8836. Construct validity was determined using principal component factor analysis by correlating the aggregated ESES items with the Generalised Self Efficacy Scale (GSE. We found that all items loaded on one factor only and that there was a

Free-floating planets from microlensing

Science.gov (United States)

Sumi, Takahiro

2014-06-01

Gravitational microlensing has an unique sensitivity to exoplanets at outside of the snow-line and even exoplanets unbound to any host stars because the technique does not rely on any light from the host but the gravity of the lens. MOA and OGLE collaborations reported the discovery of a population of unbound or distant Jupiter-mass objects, which are almost twice (1.8_{-0.8}^{+1.7}) as common as main-sequence stars, based on two years of gravitational microlensing survey observations toward the Galactic Bulge. These planetary-mass objects have no host stars that can be detected within about ten astronomical units by gravitational microlensing. However a comparison with constraints from direct imaging suggests that most of these planetary-mass objects are not bound to any host star. The such short-timescale unbound planetary candidates have been detected with the similar rate in on-going observations and these groups are working to update the analysis with larger statistics. Recently, there are also discoveries of free-floating planetary mass objects by the direct imaging in young star-forming regions and in the moving groups, but these objects are limited to massive objects of 3 to 15 Jupiter masses.They are more massive than the population found by microlensing. So they may be a different population with the different formation process, either similar with that of stars and brown dwarfs, or formed in proto-planetary disks and subsequently scattered into unbound or very distant orbits. It is important to fill the gap of these mass ranges to fully understand these populations. The Wide Field Infrared Survey Telescope (WFIRST) is the highest ranked recommendation for a large space mission in the recent New Worlds, New Horizons (NWNH) in Astronomy and Astrophysics 2010 Decadal Survey. Exoplanet microlensing program is one of the primary science of WFIRST. WFIRST will find about 3000 bound planets and 2000 unbound planets by the high precision continuous survey 15 min

76 FR 10395 - BreconRidge Manufacturing Solutions, Now Known as Sanmina-SCI Corporation, Division...

Science.gov (United States)

2011-02-24

... Solutions, Now Known as Sanmina-SCI Corporation, Division Optoelectronic and Microelectronic Design and Manufacturing, a Subsidiary of Sanmina-SCI Corporation, Including On- Site Leased Workers From Kelly Services... Manufacturing Solutions, now known as Sanmina-SCI Corporation, Division Optoelectronic and Microelectronic...

SCI peer health coach influence on self-management with peers: a qualitative analysis.

Science.gov (United States)

Skeels, S E; Pernigotti, D; Houlihan, B V; Belliveau, T; Brody, M; Zazula, J; Hasiotis, S; Seetharama, S; Rosenblum, D; Jette, A

2017-11-01

A process evaluation of a clinical trial. To describe the roles fulfilled by peer health coaches (PHCs) with spinal cord injury (SCI) during a randomized controlled trial research study called 'My Care My Call', a novel telephone-based, peer-led self-management intervention for adults with chronic SCI 1+ years after injury. Connecticut and Greater Boston Area, MA, USA. Directed content analysis was used to qualitatively examine information from 504 tele-coaching calls, conducted with 42 participants with SCI, by two trained SCI PHCs. Self-management was the focus of each 6-month PHC-peer relationship. PHCs documented how and when they used the communication tools (CTs) and information delivery strategies (IDSs) they developed for the intervention. Interaction data were coded and analyzed to determine PHC roles in relation to CT and IDS utilization and application. PHCs performed three principal roles: Role Model, Supporter, and Advisor. Role Model interactions included CTs and IDSs that allowed PHCs to share personal experiences of managing and living with an SCI, including sharing their opinions and advice when appropriate. As Supporters, PHCs used CTs and IDSs to build credible relationships based on dependability and reassuring encouragement. PHCs fulfilled the unique role of Advisor using CTs and IDSs to teach and strategize with peers about SCI self-management. The SCI PHC performs a powerful, flexible role in promoting SCI self-management among peers. Analysis of PHC roles can inform the design of peer-led interventions and highlights the importance for the provision of peer mentor training.

Exploring H2O Prominence in Reflection Spectra of Cool Giant Planets

Science.gov (United States)

MacDonald, Ryan J.; Marley, Mark S.; Fortney, Jonathan J.; Lewis, Nikole K.

2018-05-01

The H2O abundance of a planetary atmosphere is a powerful indicator of formation conditions. Inferring H2O in the solar system giant planets is challenging, due to condensation depleting the upper atmosphere of water vapor. Substantially warmer hot Jupiter exoplanets readily allow detections of H2O via transmission spectroscopy, but such signatures are often diminished by the presence of clouds composed of other species. In contrast, highly scattering water clouds can brighten planets in reflected light, enhancing molecular signatures. Here, we present an extensive parameter space survey of the prominence of H2O absorption features in reflection spectra of cool (T eff clouds brighten the planet: T eff ∼ 150 K, g ≳ 20 ms‑2, f sed ≳ 3, m ≲ 10× solar. In contrast, planets with g ≲ 20 ms‑2 and T eff ≳ 180 K display substantially prominent H2O features embedded in the Rayleigh scattering slope from 0.4 to 0.73 μm over a wide parameter space. High f sed enhances H2O features around 0.94 μm, and enables these features to be detected at lower temperatures. High m results in dampened H2O absorption features, due to water vapor condensing to form bright, optically thick clouds that dominate the continuum. We verify these trends via self-consistent modeling of the low-gravity exoplanet HD 192310c, revealing that its reflection spectrum is expected to be dominated by H2O absorption from 0.4 to 0.73 μm for m ≲ 10× solar. Our results demonstrate that H2O is manifestly detectable in reflected light spectra of cool giant planets only marginally warmer than Jupiter, providing an avenue to directly constrain the C/O and O/H ratios of a hitherto unexplored population of exoplanetary atmospheres.

Understanding Quality of Life in Adults with Spinal Cord Injury Via SCI-Related Needs and Secondary Complications.

Science.gov (United States)

Sweet, Shane N; Noreau, Luc; Leblond, Jean; Dumont, Frédéric S

2014-01-01

Understanding the factors that can predict greater quality of life (QoL) is important for adults with spinal cord injury (SCI), given that they report lower levels of QoL than the general population. To build a conceptual model linking SCI-related needs, secondary complications, and QoL in adults with SCI. Prior to testing the conceptual model, we aimed to develop and evaluate the factor structure for both SCI-related needs and secondary complications. Individuals with a traumatic SCI (N = 1,137) responded to an online survey measuring 13 SCI-related needs, 13 secondary complications, and the Life Satisfaction Questionnaire to assess QoL. The SCI-related needs and secondary complications were conceptualized into factors, tested with a confirmatory factor analysis, and subsequently evaluated in a structural equation model to predict QoL. The confirmatory factor analysis supported a 2-factor model for SCI related needs, χ(2)(61, N = 1,137) = 250.40, P SCI-related needs (β = -.22 and -.20, P SCI-related needs of individuals with SCI and preventing or managing secondary complications are essential to their QoL.

Scientific Data Processing Using SciQL

NARCIS (Netherlands)

Y. Zhang (Ying); M.L. Kersten (Martin)

2012-01-01

htmlabstractScientific discoveries increasingly rely on the ability to efficiently grind massive amounts of experimental data using database technologies. To bridge the gap between the needs of the Data-Intensive Research fields and the current DBMS technologies, we are developing SciQL (pronounced

Differential Impact and Use of a Telehealth Intervention by Persons with MS or SCI.

Science.gov (United States)

Mercier, Hannah W; Ni, Pensheng; Houlihan, Bethlyn V; Jette, Alan M

2015-11-01

The objective of this study was to compare outcomes and patterns of engaging with a telehealth intervention (CareCall) by adult wheelchair users with severe mobility limitations with a diagnosis of multiple sclerosis (MS) or spinal cord injury (SCI). The design of this study is a secondary analysis from a pilot randomized controlled trial with 106 participants with SCI and 36 participants with MS. General linear model results showed that an interaction between baseline depression score and study group significantly predicted reduced depression at 6 mos for subjects with both diagnoses (P = 0.01). For those with MS, CareCall increased participants' physical independence (P SCI (P = 0.005). Those with SCI missed more calls (P SCI, and in increasing health care access and physical independence for those with a diagnosis of MS. Future research should aim to enhance the efficacy of such an intervention for participants with SCI.

Gemini Planet Imager: Preliminary Design Report

Energy Technology Data Exchange (ETDEWEB)

Macintosh, B

2007-05-10

For the first time in history, direct and indirect detection techniques have enabled the exploration of the environments of nearby stars on scales comparable to the size of our solar system. Precision Doppler measurements have led to the discovery of the first extrasolar planets, while high-contrast imaging has revealed new classes of objects including dusty circumstellar debris disks and brown dwarfs. The ability to recover spectrophotometry for a handful of transiting exoplanets through secondary-eclipse measurements has allowed us to begin to study exoplanets as individual entities rather than points on a mass/semi-major-axis diagram and led to new models of planetary atmospheres and interiors, even though such measurements are only available at low SNR and for a handful of planets that are automatically those most modified by their parent star. These discoveries have galvanized public interest in science and technology and have led to profound new insights into the formation and evolution of planetary systems, and they have set the stage for the next steps--direct detection and characterization of extrasolar Jovian planets with instruments such as the Gemini Planet Imager (GPI). As discussed in Volume 1, the ability to directly detect Jovian planets opens up new regions of extrasolar planet phase space that in turn will inform our understanding of the processes through which these systems form, while near-IR spectra will advance our understanding of planetary physics. Studies of circumstellar debris disks using GPI's polarimetric mode will trace the presence of otherwise-invisible low-mass planets and measure the build-up and destruction of planetesimals. To accomplish the science mission of GPI will require a dedicated instrument capable of achieving contrast of 10{sup -7} or more. This is vastly better than that delivered by existing astronomical AO systems. Currently achievable contrast, about 10{sup -5} at separations of 1 arc second or larger, is

SciELO: un proyecto cooperativo para la difusión de la ciencia SciELO: A cooperative project for the dissemination of science

Directory of Open Access Journals (Sweden)

C. Bojo Canales

2009-10-01

Full Text Available Se describe el modelo SciELO (Scientific Electronic Library Online para la publicación y difusión electrónica de revistas científicas, su origen y evolución, su metodología, componentes, servicios y potencialidades, así como su implantación en España. Con 13 países participantes que suponen 8 portales certificados y 5 portales en desarrollo, más dos portales temáticos, en febrero de 2009 SciELO.org recogía 611 revistas y 195.789 artículos, de los cuales el 46% eran de Ciencias de la Salud, lo que lo convierte en una de las iniciativas de acceso abierto más importantes de cuantas existen. España se une al proyecto en 1999 y lanzó su portal "SciELO España" en 2001, con 4 revistas. En la actualidad incluye 39 títulos del área de Ciencias de la Salud, entre ellos la Revista Española de Sanidad Penitenciaria que se ha incorporado a la colección en 2007 y tiene accesibles 6 números correspondientes a los años 2007 y 2008. Se concluye afirmando que el modelo SciELO contribuye al desarrollo de la investigación y la ciencia, ofreciendo una solución eficiente y eficaz para impulsar y aumentar la difusión de las publicaciones científicas del área iberoamericana.The article describes the SciELO (Scientific Electronic Library Online model for the electronic publication and dissemination of scientific journals, its origin and evolution, methodology, components, services and potential, and its implantation in Spain. It consists of thirteen participant countries with eight certified web portals, with another 5 under development and another two thematic ones. In February 2009 Scielo.org had 611 magazines and 195,789 articles of which 46% were about health sciences. Spain became a project member in 1999 and launched the SciELO web portal in 2001, as well as 4 magazines. It currently has 39 titles in the field of Health Sciences; one of which is the Revista Española de Sanidad Penitenciaria, which joined the project in 2007 and which

Optimizing the search for transiting planets in long time series

Science.gov (United States)

Ofir, Aviv

2014-01-01

Context. Transit surveys, both ground- and space-based, have already accumulated a large number of light curves that span several years. Aims: The search for transiting planets in these long time series is computationally intensive. We wish to optimize the search for both detection and computational efficiencies. Methods: We assume that the searched systems can be described well by Keplerian orbits. We then propagate the effects of different system parameters to the detection parameters. Results: We show that the frequency information content of the light curve is primarily determined by the duty cycle of the transit signal, and thus the optimal frequency sampling is found to be cubic and not linear. Further optimization is achieved by considering duty-cycle dependent binning of the phased light curve. By using the (standard) BLS, one is either fairly insensitive to long-period planets or less sensitive to short-period planets and computationally slower by a significant factor of ~330 (for a 3 yr long dataset). We also show how the physical system parameters, such as the host star's size and mass, directly affect transit detection. This understanding can then be used to optimize the search for every star individually. Conclusions: By considering Keplerian dynamics explicitly rather than implicitly one can optimally search the BLS parameter space. The presented Optimal BLS enhances the detectability of both very short and very long period planets, while allowing such searches to be done with much reduced resources and time. The Matlab/Octave source code for Optimal BLS is made available. The MATLAB code is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/561/A138

Development and psychometric characteristics of the SCI-QOL Bladder Management Difficulties and Bowel Management Difficulties item banks and short forms and the SCI-QOL Bladder Complications scale.

Science.gov (United States)

Tulsky, David S; Kisala, Pamela A; Tate, Denise G; Spungen, Ann M; Kirshblum, Steven C

2015-05-01

To describe the development and psychometric properties of the Spinal Cord Injury--Quality of Life (SCI-QOL) Bladder Management Difficulties and Bowel Management Difficulties item banks and Bladder Complications scale. Using a mixed-methods design, a pool of items assessing bladder and bowel-related concerns were developed using focus groups with individuals with spinal cord injury (SCI) and SCI clinicians, cognitive interviews, and item response theory (IRT) analytic approaches, including tests of model fit and differential item functioning. Thirty-eight bladder items and 52 bowel items were tested at the University of Michigan, Kessler Foundation Research Center, the Rehabilitation Institute of Chicago, the University of Washington, Craig Hospital, and the James J. Peters VA Medical Center, Bronx, NY. Seven hundred fifty-seven adults with traumatic SCI. The final item banks demonstrated unidimensionality (Bladder Management Difficulties CFI=0.965; RMSEA=0.093; Bowel Management Difficulties CFI=0.955; RMSEA=0.078) and acceptable fit to a graded response IRT model. The final calibrated Bladder Management Difficulties bank includes 15 items, and the final Bowel Management Difficulties item bank consists of 26 items. Additionally, 5 items related to urinary tract infections (UTI) did not fit with the larger Bladder Management Difficulties item bank but performed relatively well independently (CFI=0.992, RMSEA=0.050) and were thus retained as a separate scale. The SCI-QOL Bladder Management Difficulties and Bowel Management Difficulties item banks are psychometrically robust and are available as computer adaptive tests or short forms. The SCI-QOL Bladder Complications scale is a brief, fixed-length outcomes instrument for individuals with a UTI.

Planet traps and planetary cores: origins of the planet-metallicity correlation

Energy Technology Data Exchange (ETDEWEB)

Hasegawa, Yasuhiro [Institute of Astronomy and Astrophysics, Academia Sinica (ASIAA), P.O. Box 23-141, Taipei 10641, Taiwan (China); Pudritz, Ralph E., E-mail: yasu@asiaa.sinica.edu.tw, E-mail: pudritz@physics.mcmaster.ca [Department of Physics and Astronomy, McMaster University, Hamilton, ON L8S 4M1 (Canada)

2014-10-10

Massive exoplanets are observed preferentially around high metallicity ([Fe/H]) stars while low-mass exoplanets do not show such an effect. This so-called planet-metallicity correlation generally favors the idea that most observed gas giants at r < 10 AU are formed via a core accretion process. We investigate the origin of this phenomenon using a semi-analytical model, wherein the standard core accretion takes place at planet traps in protostellar disks where rapid type I migrators are halted. We focus on the three major exoplanetary populations—hot Jupiters, exo-Jupiters located at r ≅ 1 AU, and the low-mass planets. We show using a statistical approach that the planet-metallicity correlations are well reproduced in these models. We find that there are specific transition metallicities with values [Fe/H] = –0.2 to –0.4, below which the low-mass population dominates, and above which the Jovian populations take over. The exo-Jupiters significantly exceed the hot Jupiter population at all observed metallicities. The low-mass planets formed via the core accretion are insensitive to metallicity, which may account for a large fraction of the observed super-Earths and hot-Neptunes. Finally, a controlling factor in building massive planets is the critical mass of planetary cores (M {sub c,} {sub crit}) that regulates the onset of rapid gas accretion. Assuming the current data is roughly complete at [Fe/H] > –0.6, our models predict that the most likely value of the 'mean' critical core mass of Jovian planets is (M {sub c,} {sub crit}) ≅ 5 M {sub ⊕} rather than 10 M {sub ⊕}. This implies that grain opacities in accreting envelopes should be reduced in order to lower M {sub c,} {sub crit}.

The fate of scattered planets

Energy Technology Data Exchange (ETDEWEB)

Bromley, Benjamin C. [Department of Physics and Astronomy, University of Utah, 115 S 1400 E, Rm 201, Salt Lake City, UT 84112 (United States); Kenyon, Scott J., E-mail: bromley@physics.utah.edu, E-mail: skenyon@cfa.harvard.edu [Smithsonian Astrophysical Observatory, 60 Garden Street, Cambridge, MA 02138 (United States)

2014-12-01

As gas giant planets evolve, they may scatter other planets far from their original orbits to produce hot Jupiters or rogue planets that are not gravitationally bound to any star. Here, we consider planets cast out to large orbital distances on eccentric, bound orbits through a gaseous disk. With simple numerical models, we show that super-Earths can interact with the gas through dynamical friction to settle in the remote outer regions of a planetary system. Outcomes depend on planet mass, the initial scattered orbit, and the evolution of the time-dependent disk. Efficient orbital damping by dynamical friction requires planets at least as massive as the Earth. More massive, longer-lived disks damp eccentricities more efficiently than less massive, short-lived ones. Transition disks with an expanding inner cavity can circularize orbits at larger distances than disks that experience a global (homologous) decay in surface density. Thus, orbits of remote planets may reveal the evolutionary history of their primordial gas disks. A remote planet with an orbital distance ∼100 AU from the Sun is plausible and might explain correlations in the orbital parameters of several distant trans-Neptunian objects.

DETECTING OCEANS ON EXTRASOLAR PLANETS USING THE GLINT EFFECT

International Nuclear Information System (INIS)

Robinson, Tyler D.; Meadows, Victoria S.; Crisp, David

2010-01-01

Glint, the specular reflection of sunlight off Earth's oceans, may reveal the presence of oceans on an extrasolar planet. As an Earth-like planet nears crescent phases, the size of the ocean glint spot increases relative to the fraction of the illuminated disk, while the reflectivity of this spot increases. Both effects change the planet's visible reflectivity as a function of phase. However, strong forward scattering of radiation by clouds can also produce increases in a planet's reflectivity as it approaches crescent phases, and surface glint can be obscured by Rayleigh scattering and atmospheric absorption. Here, we explore the detectability of glint in the presence of an atmosphere and realistic phase-dependent scattering from oceans and clouds. We use the NASA Astrobiology Institute's Virtual Planetary Laboratory three-dimensional line-by-line, multiple-scattering spectral Earth model to simulate Earth's broadband visible brightness and reflectivity over an orbit. Our validated simulations successfully reproduce phase-dependent Earthshine observations. We find that the glinting Earth can be as much as 100% brighter at crescent phases than simulations that do not include glint, and that the effect is dependent on both orbital inclination and wavelength, where the latter dependence is caused by Rayleigh scattering limiting sensitivity to the surface. We show that this phenomenon may be observable using the James Webb Space Telescope paired with an external occulter.

Search for a planet

International Nuclear Information System (INIS)

Tokovinin, A.A.

1986-01-01

The problem of search for star planets is discussed in a popular form. Two methods of search for planets are considered: astrometric and spectral. Both methods complement one another. An assumption is made that potential possessors of planets are in the first place yellow and red dwarfs with slow axial rotation. These stars are the most numerous representatives of Galaxy population

Long-life mission reliability for outer planet atmospheric entry probes

Science.gov (United States)

Mccall, M. T.; Rouch, L.; Maycock, J. N.

1976-01-01

The results of a literature analysis on the effects of prolonged exposure to deep space environment on the properties of outer planet atmospheric entry probe components are presented. Materials considered included elastomers and plastics, pyrotechnic devices, thermal control components, metal springs and electronic components. The rates of degradation of each component were determined and extrapolation techniques were used to predict the effects of exposure for up to eight years to deep space. Pyrotechnic devices were aged under accelerated conditions to an equivalent of eight years in space and functionally tested. Results of the literature analysis of the selected components and testing of the devices indicated that no severe degradation should be expected during an eight year space mission.

Looking Into Pandora's Box: The Content Of Sci-Hub And Its Usage

OpenAIRE

Greshake, Bastian

2017-01-01

Despite the growth of Open Access, potentially illegally circumventing paywalls to access scholarly publications is becoming a more mainstream phenomenon. The web service Sci-Hub is amongst the biggest facilitators of this, offering free access to around 62 million publications. So far it is not well studied how and why its users are accessing publications through Sci-Hub. By utilizing the recently released corpus of Sci-Hub and comparing it to the data of  ~28 million downloads done through ...

Long Term Evolution of Planetary Systems with a Terrestrial Planet and a Giant Planet

Science.gov (United States)

Georgakarakos, Nikolaos; Dobbs-Dixon, Ian; Way, Michael J.

2016-01-01

We study the long term orbital evolution of a terrestrial planet under the gravitational perturbations of a giant planet. In particular, we are interested in situations where the two planets are in the same plane and are relatively close. We examine both possible configurations: the giant planet orbit being either outside or inside the orbit of the smaller planet. The perturbing potential is expanded to high orders and an analytical solution of the terrestrial planetary orbit is derived. The analytical estimates are then compared against results from the numerical integration of the full equations of motion and we find that the analytical solution works reasonably well. An interesting finding is that the new analytical estimates improve greatly the predictions for the timescales of the orbital evolution of the terrestrial planet compared to an octupole order expansion. Finally, we briefly discuss possible applications of the analytical estimates in astrophysical problems.

Methodology for the AutoRegressive Planet Search (ARPS) Project

Science.gov (United States)

Feigelson, Eric; Caceres, Gabriel; ARPS Collaboration

2018-01-01

The detection of periodic signals of transiting exoplanets is often impeded by the presence of aperiodic photometric variations. This variability is intrinsic to the host star in space-based observations (typically arising from magnetic activity) and from observational conditions in ground-based observations. The most common statistical procedures to remove stellar variations are nonparametric, such as wavelet decomposition or Gaussian Processes regression. However, many stars display variability with autoregressive properties, wherein later flux values are correlated with previous ones. Providing the time series is evenly spaced, parametric autoregressive models can prove very effective. Here we present the methodology of the Autoregessive Planet Search (ARPS) project which uses Autoregressive Integrated Moving Average (ARIMA) models to treat a wide variety of stochastic short-memory processes, as well as nonstationarity. Additionally, we introduce a planet-search algorithm to detect periodic transits in the time-series residuals after application of ARIMA models. Our matched-filter algorithm, the Transit Comb Filter (TCF), replaces the traditional box-fitting step. We construct a periodogram based on the TCF to concentrate the signal of these periodic spikes. Various features of the original light curves, the ARIMA fits, the TCF periodograms, and folded light curves at peaks of the TCF periodogram can then be collected to provide constraints for planet detection. These features provide input into a multivariate classifier when a training set is available. The ARPS procedure has been applied NASA's Kepler mission observations of ~200,000 stars (Caceres, Dissertation Talk, this meeting) and will be applied in the future to other datasets.

Direct Imaging of Warm Extrasolar Planets

International Nuclear Information System (INIS)

Macintosh, B

2005-01-01

One of the most exciting scientific discoveries in the last decade of the twentieth century was the first detection of planets orbiting a star other than our own. By now more than 130 extrasolar planets have been discovered indirectly, by observing the gravitational effects of the planet on the radial velocity of its parent star. This technique has fundamental limitations: it is most sensitive to planets close to their star, and it determines only a planet's orbital period and a lower limit on the planet's mass. As a result, all the planetary systems found so far are very different from our own--they have giant Jupiter-sized planets orbiting close to their star, where the terrestrial planets are found in our solar system. Such systems have overturned the conventional paradigm of planet formation, but have no room in them for habitable Earth-like planets. A powerful complement to radial velocity detections of extrasolar planets will be direct imaging--seeing photons from the planet itself. Such a detection would allow photometric measurements to determine the temperature and radius of a planet. Also, direct detection is most sensitive to planets in wide orbits, and hence more capable of seeing solar systems resembling our own, since a giant planet in a wide orbit does not preclude the presence of an Earth-like planet closer to the star. Direct detection, however, is extremely challenging. Jupiter is roughly a billion times fainter than our sun. Two techniques allowed us to overcome this formidable contrast and attempt to see giant planets directly. The first is adaptive optics (AO) which allows giant earth-based telescopes, such as the 10 meter W.M. Keck telescope, to partially overcome the blurring effects of atmospheric turbulence. The second is looking for young planets: by searching in the infrared for companions to young stars, we can see thermal emission from planets that are still warm with the heat of their formation. Together with a UCLA team that leads the

The Fate of Unstable Circumbinary Planets

Science.gov (United States)

Kohler, Susanna

2016-03-01

What happens to Tattooine-like planets that are instead in unstable orbits around their binary star system? A new study examines whether such planets will crash into a host star, get ejected from the system, or become captured into orbit around one of their hosts.Orbit Around a DuoAt this point we have unambiguously detected multiple circumbinary planets, raising questions about these planets formation and evolution. Current models suggest that it is unlikely that circumbinary planets would be able to form in the perturbed environment close their host stars. Instead, its thought that the planets formed at a distance and then migrated inwards.One danger such planets face when migrating is encountering ranges of radii where their orbits become unstable. Two scientists at the University of Chicago, Adam Sutherland and Daniel Fabrycky, have studied what happens when circumbinary planets migrate into such a region and develop unstable orbits.Producing Rogue PlanetsTime for planets to either be ejected or collide with one of the two stars, as a function of the planets starting distance (in AU) from the binary barycenter. Colors represent different planetary eccentricities. [Sutherland Fabrycky 2016]Sutherland and Fabrycky used N-body simulations to determine the fates of planets orbiting around a star system consisting of two stars a primary like our Sun and a secondary roughly a tenth of its size that are separated by 1 AU.The authors find that the most common fate for a circumbinary planet with an unstable orbit is ejection from the system; over 80% of unstable planets were ejected. This has interesting implications: if the formation of circumbinary planets is common, this mechanism could be filling the Milky Way with a population of free-floating, rogue planets that no longer are associated with their host star.The next most common outcome for unstable planets is collision with one of their host stars (most often the secondary), resulting inaccretion of the planet

SciLab Based Remote Control of Thermo-Optical Plant

Directory of Open Access Journals (Sweden)

Miroslav Jano

2011-11-01

Full Text Available The paper deals with the web-based implementation of the control system of a thermo-optical plant. The control of the plant is based on the SciLab software which originally is not designed for web-based applications. The paper shows a possible way to circumvent this limitation. The ultimate goal is to enable remote controlled experiment using SciLab. The paper also describes possible tools for communication and control of the real plant and visualization of results.

Three Small Planets Transiting the Bright Young Field Star K2-233

Science.gov (United States)

David, Trevor J.; Crossfield, Ian J. M.; Benneke, Björn; Petigura, Erik A.; Gonzales, Erica J.; Schlieder, Joshua E.; Yu, Liang; Isaacson, Howard T.; Howard, Andrew W.; Ciardi, David R.; Mamajek, Eric E.; Hillenbrand, Lynne A.; Cody, Ann Marie; Riedel, Adric; Schwengeler, Hans Martin; Tanner, Christopher; Ende, Martin

2018-05-01

We report the detection of three small transiting planets around the young K3 dwarf K2-233 (2MASS J15215519‑2013539) from observations during Campaign 15 of the K2 mission. The star is relatively nearby (d = 69 pc) and bright (V = 10.7 mag, K s = 8.4 mag), making the planetary system an attractive target for radial velocity follow-up and atmospheric characterization with the James Webb Space Telescope. The inner two planets are hot super-Earths (R b = 1.40 ± 0.06 {R}\\oplus , R c = 1.34 ± 0.08 {R}\\oplus ), while the outer planet is a warm sub-Neptune (R d = 2.6 ± 0.1 {R}\\oplus ). We estimate the stellar age to be {360}-140+490 Myr based on rotation, activity, and kinematic indicators. The K2-233 system is particularly interesting given recent evidence for inflated radii in planets around similarly aged stars, a trend potentially related to photo-evaporation, core cooling, or both mechanisms.

Weighted local Hardy spaces associated with operators

Indian Academy of Sciences (India)

RUMING GONG

2018-04-24

5 days ago ... Studies 116 (1985) (Amsterdam: North Holland). [12] Gong R M and Yan L X, Littlewood–Paley and spectral multipliers on weighted L p spaces, J. Geom. Anal. 24 (2014) 873–900. [13] Gong R M, Li J and Yan L X, A local version of Hardy spaces associated with operators on metric spaces, Sci. China Math.

Implication of altered autonomic control for orthostatic tolerance in SCI.

Science.gov (United States)

Wecht, Jill Maria; Bauman, William A

2018-01-01

Neural output from the sympathetic and parasympathetic branches of the autonomic nervous system (ANS) are integrated to appropriately control cardiovascular responses during routine activities of daily living including orthostatic positioning. Sympathetic control of the upper extremity vasculature and the heart arises from the thoracic cord between T1 and T5, whereas splanchnic bed and lower extremity vasculature receive sympathetic neural input from the lower cord between segments T5 and L2. Although the vasculature is not directly innervated by the parasympathetic nervous system, the SA node is innervated by post-ganglionic vagal nerve fibers via cranial nerve X. Segmental differences in sympathetic cardiovascular innervation highlight the effect of lesion level on orthostatic cardiovascular control following spinal cord injury (SCI). Due to impaired sympathetic cardiovascular control, many individuals with SCI, particularly those with lesions above T6, are prone to orthostatic hypotension (OH) and orthostatic intolerance (OI). Symptomatic OH, which may result in OI, is a consequence of episodic reductions in cerebral perfusion pressure and the symptoms may include: dizziness, lightheadedness, nausea, blurred vision, ringing in the ears, headache and syncope. However, many, if not most, individuals with SCI who experience persistent and episodic hypotension and OH do not report symptoms of cerebral hypoperfusion and therefore do not raise clinical concern. This review will discuss the mechanism underlying OH and OI following SCI, and will review our knowledge to date regarding the prevalence, consequences and possible treatment options for these conditions in the SCI population. Published by Elsevier B.V.

Optical Images of an Exosolar Planet 25 Light-Years from Earth

Science.gov (United States)

Clampin, Mark

2008-01-01

Fomalhaut is a bright star 7.7 parsec (25 light year) from Earth that harbors a belt of cold dust with a structure consistent with gravitational sculpting by an orbiting planet. Here, we present optical observations of an exoplanet candidate. Fomalhaut b. In the plane of the belt, Fomalhaut b lies approximately 119 astronomical units (AU) from the star, and within 18 All of the dust belt. We detect counterclockwise orbital motion using Hubble Space Telescope observations separated by 1.73 years. Dynamical models of the interaction between the planet and the belt indicate that the planet's mass is at most three times that of Jupiter for the belt to avoid gravitational disruption. The flux detected at 0.8 micron flux is also consistent with that of a planet with mass a few limes that of Jupiter. The brightness at 0.6 microns and the lack of detection at longer wavelengths suggest that the detected flux may include starlight reflected off a circumplanetary disk, with dimension comparable to the orbits of the Galilean satellites. We also observed variability of unknown origin at 0.6 microns.

Optical Images of an Exosolar Planet 25 Light Years from Earth

Science.gov (United States)

Kalas, Paul; Graham, James R.; Chiang, Eugene; Fitzgerald, Michael P.; Clampin, Mark; Kite, Edwin S.; Stapelfeldt, Karl; Marois, Christian; Krist, John

2008-01-01

Fomalhaut is a bright star 7.7 parsecs (25 light years) from Earth that harbors a belt of cold dust with a structure consistent with gravitational sculpting by an orbiting planet. Here, we present optical observations of an exoplanet candidate, Fomalhaut b. In the plane of the belt, Fomalhaut b lies approximately 119 astronomical units (AU) from the star and 18 AU from the dust belt, matching predictions. We detect counterclockwise orbital motion using Hubble Space Telescope observations separated by 1.73 years. Dynamical models of the interaction between the planet and the belt indicate that the planet's mass is at most three times that of Jupiter for the belt to avoid gravitational disruption. The flux detected at 0.8 m is also consistent with that of a planet with mass no greater than a few times that of Jupiter. The brightness at 0.6 micron and the lack of detection at longer wavelengths suggest that the detected flux may include starlight reflected off a circumplanetary disk, with dimension comparable to the orbits of the Galilean satellites. We also observed variability of unknown origin at 0.6 micron.

SCI- databasen - En klinisk rygmarvsskade database

DEFF Research Database (Denmark)

Vibjerg, Jørgen; Østergaard, Niels; Hagen, Ellen Merete

2015-01-01

SCI- databasen - En klinisk rygmarvsskade database Målet med databasen er at indsamle vigtige data for rygmarvskadede patienter med henblik på at sikrer information der kan bruges til fremtidig forskning. Målet er desuden at kunne bruge databasen i et fremtidig klinisk arbejde, der som et...

The origin of high eccentricity planets: The dispersed planet formation regime for weakly magnetized disks

Directory of Open Access Journals (Sweden)

Yusuke Imaeda

2017-03-01

Full Text Available In the tandem planet formation regime, planets form at two distinct sites where solid particles are densely accumulated due to the on/off state of the magnetorotational instability (MRI. We found that tandem planet formation can reproduce the solid component distribution of the Solar System and tends to produce a smaller number of large planets through continuous pebble flow into the planet formation sites. In the present paper, we investigate the dependence of tandem planet formation on the vertical magnetic field of the protoplanetary disk. We calculated two cases of Bz=3.4×10−3 G and Bz=3.4×10−5 G at 100 AU as well as the canonical case of Bz=3.4×10−4 G. We found that tandem planet formation holds up well in the case of the strong magnetic field (Bz=3.4×10−3 G. On the other hand, in the case of a weak magnetic field (Bz=3.4×10−5 G at 100 AU, a new regime of planetary growth is realized: the planets grow independently at different places in the dispersed area of the MRI-suppressed region of r=8−30 AU at a lower accretion rate of M˙<10−7.4 M⊙yr−1. We call this the “dispersed planet formation” regime. This may lead to a system with a larger number of smaller planets that gain high eccentricity through mutual collisions.

STABILIZING CLOUD FEEDBACK DRAMATICALLY EXPANDS THE HABITABLE ZONE OF TIDALLY LOCKED PLANETS

International Nuclear Information System (INIS)

Yang Jun; Abbot, Dorian S.; Cowan, Nicolas B.

2013-01-01

The habitable zone (HZ) is the circumstellar region where a planet can sustain surface liquid water. Searching for terrestrial planets in the HZ of nearby stars is the stated goal of ongoing and planned extrasolar planet surveys. Previous estimates of the inner edge of the HZ were based on one-dimensional radiative-convective models. The most serious limitation of these models is the inability to predict cloud behavior. Here we use global climate models with sophisticated cloud schemes to show that due to a stabilizing cloud feedback, tidally locked planets can be habitable at twice the stellar flux found by previous studies. This dramatically expands the HZ and roughly doubles the frequency of habitable planets orbiting red dwarf stars. At high stellar flux, strong convection produces thick water clouds near the substellar location that greatly increase the planetary albedo and reduce surface temperatures. Higher insolation produces stronger substellar convection and therefore higher albedo, making this phenomenon a stabilizing climate feedback. Substellar clouds also effectively block outgoing radiation from the surface, reducing or even completely reversing the thermal emission contrast between dayside and nightside. The presence of substellar water clouds and the resulting clement surface conditions will therefore be detectable with the James Webb Space Telescope.

The First Circumbinary Planet Found by Microlensing: OGLE-2007-BLG-349L(AB)c

Science.gov (United States)

Bennett, D. P.; Rhie, S. H.; Udalski, A.; Gould, A.; Tsapras, Y.; Kubas, D.; Bond, I. A.; Greenhill, J.; Cassan, A.; Rattenbury, N. J.;

Glimpses of far away places: Intensive atmosphere characterization of extrasolar planets

Science.gov (United States)

Kreidberg, Laura

Exoplanet atmosphere characterization has the potential to reveal the origins, nature, and even habitability of distant worlds. This thesis represents a step towards realizing that potential for a diverse group of four extrasolar planets. Here, I present the results of intensive observational campaigns with the Hubble and Spitzer Space Telescopes to study the atmospheres of the super-Earth GJ 1214b and the hot Jupiters WASP-43b, WASP-12b, and WASP-103b. I measured an unprecedentedly precise near-infrared transmission spectrum for GJ 1214b that definitively reveals the presence of clouds in the planet's atmosphere. For WASP-43b and WASP-12b, I also measured very precise spectra that exhibit water features at high confidence (>7 sigma). The retrieved water abundance for WASP-43b extends the well-known Solar System trend of decreasing atmospheric metallicity with increasing planet mass. The detection of water for WASP-12b marks the first spectroscopic identification of a molecule in the planet's atmosphere and implies that it has solar composition, ruling out carbon-to-oxygen ratios greater than unity. For WASP-103b, I present preliminary results from the new technique of phase-resolved spectroscopy to determine the planet's temperature structure, dynamics, and energy budget. In addition to these observations, I also describe the BATMAN code, an open-source Python package for fast and flexible modeling of transit light curves. Taken together, these results provide a foundation for comparative planetology beyond the Solar System and the investigation of Earth-like, potentially habitable planets with future observing facilities.

THREE PLANETS ORBITING WOLF 1061

Energy Technology Data Exchange (ETDEWEB)

Wright, D. J.; Wittenmyer, R. A.; Tinney, C. G.; Bentley, J. S.; Zhao, Jinglin, E-mail: duncan.wright@unsw.edu.au [Department of Astronomy and Australian Centre for Astrobiology, School of Physics, University of New South Wales, NSW 2052 (Australia)

2016-02-01

We use archival HARPS spectra to detect three planets orbiting the M3 dwarf Wolf 1061 (GJ 628). We detect a 1.36 M{sub ⊕} minimum-mass planet with an orbital period P = 4.888 days (Wolf 1061b), a 4.25 M{sub ⊕} minimum-mass planet with orbital period P = 17.867 days (Wolf 1061c), and a likely 5.21 M{sub ⊕} minimum-mass planet with orbital period P = 67.274 days (Wolf 1061d). All of the planets are of sufficiently low mass that they may be rocky in nature. The 17.867 day planet falls within the habitable zone for Wolf 1061 and the 67.274 day planet falls just outside the outer boundary of the habitable zone. There are no signs of activity observed in the bisector spans, cross-correlation FWHMs, calcium H and K indices, NaD indices, or Hα indices near the planetary periods. We use custom methods to generate a cross-correlation template tailored to the star. The resulting velocities do not suffer the strong annual variation observed in the HARPS DRS velocities. This differential technique should deliver better exploitation of the archival HARPS data for the detection of planets at extremely low amplitudes.

Migration of accreting giant planets

Science.gov (United States)

Crida, A.; Bitsch, B.; Raibaldi, A.

2016-12-01

We present the results of 2D hydro simulations of giant planets in proto-planetary discs, which accrete gas at a more or less high rate. First, starting from a solid core of 20 Earth masses, we show that as soon as the runaway accretion of gas turns on, the planet is saved from type I migration : the gap opening mass is reached before the planet is lost into its host star. Furthermore, gas accretion helps opening the gap in low mass discs. Consequently, if the accretion rate is limited to the disc supply, then the planet is already inside a gap and in type II migration. We further show that the type II migration of a Jupiter mass planet actually depends on its accretion rate. Only when the accretion is high do we retrieve the classical picture where no gas crosses the gap and the planet follows the disc spreading. These results impact our understanding of planet migration and planet population synthesis models. The e-poster presenting these results in French can be found here: L'e-poster présentant ces résultats en français est disponible à cette adresse: http://sf2a.eu/semaine-sf2a/2016/posterpdfs/156_179_49.pdf.

Harvesting space for a greener earth

CERN Document Server

Matloff, Greg; Johnson, Les

2014-01-01

What was our planet like in years past? How has our civilization affected Earth and its ecology? Harvesting Space for a Greener Planet, the Second Edition of Paradise Regained: The Regreening of the Earth, begins by discussing these questions, and then generates a scenario for the restoration of Earth. It introduces new and innovative ideas on how we could use the Solar System and its resources for terrestrial benefit. The environmental challenges that face us today cannot be resolved by conservation and current technologies alone. Harvesting Space highlights the risk of humankind’s future extinction from environmental degradation. Population growth, global climate change, and maintaining sustainability of habitats for wildlife are all considered, among other issues. Rather than losing heart, we need to realize that the solutions to these problems lie in being good stewards of the planet and in the development of space. Not only will the solutions offered here avert a crisis, they will also provide the basi...

International Deep Planet Survey, 317 stars to determine the wide-separated planet frequency

Science.gov (United States)

Galicher, R.; Marois, C.; Macintosh, B.; Zuckerman, B.; Song, I.; Barman, T.; Patience, J.

2013-09-01

Since 2000, more than 300 nearby young stars were observed for the International Deep Planet Survey with adaptive optics systems at Gemini (NIRI/NICI), Keck (Nirc2), and VLT (Naco). Massive young AF stars were included in our sample whereas they have generally been neglected in first generation surveys because the contrast and target distances are less favorable to image substellar companions. The most significant discovery of the campaign is the now well-known HR 8799 multi-planet system. This remarkable finding allows, for the first time, an estimate of the Jovians planet population at large separations (further than a few AUs) instead of deriving upper limits. During my presentation, I will present the survey showing images of multiple stars and planets. I will then propose a statistic study of the observed stars deriving constraints on the Jupiter-like planet frequency at large separations.

sciARTbooklet: Rachael Nee / Potato Powered Cosmos

CERN Multimedia

Hoch, Michael

2017-01-01

Rachael Nee rachaelnee@gmail.com graduated from MA Fine Art at Chelsea College of Arts, UK with Distinction in 2015, her art practice is concerned with energy, entropy and matter. www.rachaelnee.comart@CMS_sciARTbooklet: web page : http://artcms.web.cern.ch/artcms/ A tool to support students with their research on various scientific topics, encourage an understanding of the relevance of expression through the arts, a manual to recreate the artwork and enable students to define and develop their own artistic inquiry in the creation of new artworks. The art@CMS sciART booklet series directed by Dr. Michael Hoch, michael.hoch@cern.ch scientist and artist at CERN, in collaboration with the HST 2017 participants (S. Bellefontaine, S. Chaiwan, A. Djune Tchinda, R. O’Keeffe, G. Shumanova)

An Astrobiological Experiment to Explore the Habitability of Tidally Locked M-Dwarf Planets

Science.gov (United States)

Angerhausen, Daniel; Sapers, Haley; Simoncini, Eugenio; Lutz, Stefanie; Alexandre, Marcelo da Rosa; Galante, Douglas

2014-04-01

We present a summary of a three-year academic research proposal drafted during the Sao Paulo Advanced School of Astrobiology (SPASA) to prepare for upcoming observations of tidally locked planets orbiting M-dwarf stars. The primary experimental goal of the suggested research is to expose extremophiles from analogue environments to a modified space simulation chamber reproducing the environmental parameters of a tidally locked planet in the habitable zone of a late-type star. Here we focus on a description of the astronomical analysis used to define the parameters for this climate simulation.

SciCloud: A Scientific Cloud and Management Platform for Smart City Data

DEFF Research Database (Denmark)

Liu, Xiufeng; Nielsen, Per Sieverts; Heller, Alfred

2017-01-01

private scientific cloud, SciCloud, to tackle these grand challenges. SciCloud provides on-demand computing resource provisions, a scalable data management platform and an in-place data analytics environment to support the scientific research using smart city data....

OPENING REMARKS: SciDAC: Scientific Discovery through Advanced Computing

Science.gov (United States)

Strayer, Michael

2005-01-01

Good morning. Welcome to SciDAC 2005 and San Francisco. SciDAC is all about computational science and scientific discovery. In a large sense, computational science characterizes SciDAC and its intent is change. It transforms both our approach and our understanding of science. It opens new doors and crosses traditional boundaries while seeking discovery. In terms of twentieth century methodologies, computational science may be said to be transformational. There are a number of examples to this point. First are the sciences that encompass climate modeling. The application of computational science has in essence created the field of climate modeling. This community is now international in scope and has provided precision results that are challenging our understanding of our environment. A second example is that of lattice quantum chromodynamics. Lattice QCD, while adding precision and insight to our fundamental understanding of strong interaction dynamics, has transformed our approach to particle and nuclear science. The individual investigator approach has evolved to teams of scientists from different disciplines working side-by-side towards a common goal. SciDAC is also undergoing a transformation. This meeting is a prime example. Last year it was a small programmatic meeting tracking progress in SciDAC. This year, we have a major computational science meeting with a variety of disciplines and enabling technologies represented. SciDAC 2005 should position itself as a new corner stone for Computational Science and its impact on science. As we look to the immediate future, FY2006 will bring a new cycle to SciDAC. Most of the program elements of SciDAC will be re-competed in FY2006. The re-competition will involve new instruments for computational science, new approaches for collaboration, as well as new disciplines. There will be new opportunities for virtual experiments in carbon sequestration, fusion, and nuclear power and nuclear waste, as well as collaborations

A SEARCH FOR SHORT-PERIOD ROCKY PLANETS AROUND WDs WITH THE COSMIC ORIGINS SPECTROGRAPH (COS)

Energy Technology Data Exchange (ETDEWEB)

Sandhaus, Phoebe H.; Debes, John H.; Ely, Justin; Hines, Dean C.; Bourque, Matthew [Space Telescope Science Institute, 3700 San Martin Dr., Baltimore, MD 21218 (United States)

2016-05-20

The search for transiting habitable exoplanets has broadened to include several types of stars that are smaller than the Sun in an attempt to increase the observed transit depth and hence the atmospheric signal of the planet. Of all spectral types, white dwarfs (WDs) are the most favorable for this type of investigation. The fraction of WDs that possess close-in rocky planets is unknown, but several large angle stellar surveys have the photometric precision and cadence to discover at least one if they are common. Ultraviolet observations of WDs may allow for detection of molecular oxygen or ozone in the atmosphere of a terrestrial planet. We use archival Hubble Space Telescope data from the Cosmic Origins Spectrograph to search for transiting rocky planets around UV-bright WDs. In the process, we discovered unusual variability in the pulsating WD GD 133, which shows slow sinusoidal variations in the UV. While we detect no planets around our small sample of targets, we do place stringent limits on the possibility of transiting planets, down to sub-lunar radii. We also point out that non-transiting small planets in thermal equilibrium are detectable around hotter WDs through infrared excesses, and identify two candidates.

Neuropathic pain and SCI: Identification and treatment strategies in the 21st century.

Science.gov (United States)

Hatch, Maya N; Cushing, Timothy R; Carlson, Gregory D; Chang, Eric Y

2018-01-15

Pain is a common complication in patients following spinal cord injury (SCI), with studies citing up to 80% of patients reporting some form of pain. Neuropathic pain (NP) makes up a substantial percentage of all pain symptoms in patients with SCI and is often complex. Given the high prevalence of NP in patients with SCI, proper identification and treatment is imperative. Indeed, identification of pain subtypes is a vital step toward determining appropriate treatment. A variety of pharmacological and non-pharmacological treatments can be undertaken including antiepileptics, tricyclic antidepressants, opioids, transcranial direct current stimulation, and invasive surgical procedures. Despite all the available treatment options and advances in the field of SCI medicine, providing adequate treatment of NP after SCI continues to be challenging. It is therefore extremely important for clinicians to have a strong foundation in the identification of SCI NP, as well as an understanding of appropriate treatment options. Here, we highlight the definitions and classification tools available for NP identification, and discuss current treatment options. We hope that this will not only provide a better understanding of NP for physicians in various subspecialties, but that it will also help guide future research on this subject. Copyright © 2017 Elsevier B.V. All rights reserved.

The Earth as a Distant Planet A Rosetta Stone for the Search of Earth-Like Worlds

CERN Document Server

Vázquez, M; Montañés Rodríguez, P

2010-01-01

Is the Earth, in some way, special? Or is our planet but one of the millions of other inhabited planets within our galaxy? This is an exciting time to be asking this old question, because for the first time in history, the answer is within reach. In The Earth as a Distant Planet, the authors set themselves as external observers of our Solar System from an astronomical distance. From that perspective, the authors describe how the Earth, the third planet in distance to the central star, can be catalogued as having its own unique features and as capable of sustaining life. The knowledge gained from this original perspective is then applied to the ongoing search for planets outside the solar system, or exoplanets. Since the discovery in 1992 of the first exoplanet, the number of known planets has increased exponentially. Ambitious space missions are already being designed for the characterization of their atmospheres and to explore the possibility that they host life. The exploration of Earth and the rest of the ...

Institutional profile: the national Swedish academic drug discovery & development platform at SciLifeLab.

Science.gov (United States)

Arvidsson, Per I; Sandberg, Kristian; Sakariassen, Kjell S

2017-06-01

The Science for Life Laboratory Drug Discovery and Development Platform (SciLifeLab DDD) was established in Stockholm and Uppsala, Sweden, in 2014. It is one of ten platforms of the Swedish national SciLifeLab which support projects run by Swedish academic researchers with large-scale technologies for molecular biosciences with a focus on health and environment. SciLifeLab was created by the coordinated effort of four universities in Stockholm and Uppsala: Stockholm University, Karolinska Institutet, KTH Royal Institute of Technology and Uppsala University, and has recently expanded to other Swedish university locations. The primary goal of the SciLifeLab DDD is to support selected academic discovery and development research projects with tools and resources to discover novel lead therapeutics, either molecules or human antibodies. Intellectual property developed with the help of SciLifeLab DDD is wholly owned by the academic research group. The bulk of SciLifeLab DDD's research and service activities are funded from the Swedish state, with only consumables paid by the academic research group through individual grants.

Space storms and radiation causes and effects

CERN Document Server

Schrijver, Carolus J

2010-01-01

Heliophysics is a fast-developing scientific discipline that integrates studies of the Sun's variability, the surrounding heliosphere, and the environment and climate of planets. The Sun is a magnetically variable star and for planets with intrinsic magnetic fields, planets with atmospheres, or planets like Earth with both, there are profound consequences. This 2010 volume, the second in this series of three heliophysics texts, integrates the many aspects of space storms and the energetic radiation associated with them - from causes on the Sun to effects in planetary environments. It reviews t

Gravitational Microlensing of Earth-mass Planets

DEFF Research Database (Denmark)

Harpsøe, Kennet Bomann West

It was only 17 years ago that the first planet outside of our own solar system was detected in the form of 51 Pegasi b. This planet is unlike anything in our own solar system. In fact, this planet was the first representative of a class of planets later known as “hot Jupiters”– gas giants......, i.e. it is much easier to detect high mass planets in close orbits. With these two methods it is hard to detect planets in an exo-solar system with a structure similar to our own solar system; specifically, it is hard to detect Earth-like planets in Earth-like orbits. It is presently unknown how...... common such planets are in our galaxy. There are a few other known methods for detecting exoplanets which have very different bias patterns. This thesis has been divided into two parts, treating two of these other methods. Part I is dedicated to the method of gravitational microlensing, a method...

Rocky Planet Formation: Quick and Neat

Science.gov (United States)

Kenyon, Scott J.; Najita, Joan R.; Bromley, Benjamin C.

2016-11-01

We reconsider the commonly held assumption that warm debris disks are tracers of terrestrial planet formation. The high occurrence rate inferred for Earth-mass planets around mature solar-type stars based on exoplanet surveys (˜20%) stands in stark contrast to the low incidence rate (≤2%-3%) of warm dusty debris around solar-type stars during the expected epoch of terrestrial planet assembly (˜10 Myr). If Earth-mass planets at au distances are a common outcome of the planet formation process, this discrepancy suggests that rocky planet formation occurs more quickly and/or is much neater than traditionally believed, leaving behind little in the way of a dust signature. Alternatively, the incidence rate of terrestrial planets has been overestimated, or some previously unrecognized physical mechanism removes warm dust efficiently from the terrestrial planet region. A promising removal mechanism is gas drag in a residual gaseous disk with a surface density ≳10-5 of the minimum-mass solar nebula.

The Runaway Greenhouse Effect on Earth and other Planets

Science.gov (United States)

Rabbette, Maura; Pilewskie, Peter; McKay, Christopher; Young, Robert

2001-01-01

Water vapor is an efficient absorber of outgoing longwave infrared radiation on Earth and is the primary greenhouse gas. Since evaporation increases with increasing sea surface temperature, and the increase in water vapor further increases greenhouse warming, there is a positive feedback. The runaway greenhouse effect occurs if this feedback continues unchecked until all the water has left the surface and enters the atmosphere. For Mars and the Earth the runaway greenhouse was halted when water vapor became saturated with respect to ice or liquid water respectively. However, Venus is considered to be an example of a planet where the runaway greenhouse effect did occur, and it has been speculated that if the solar luminosity were to increase above a certain limit, it would also occur on the Earth. Satellite data acquired during the Earth Radiation Budget Experiment (ERBE) under clear sky conditions shows that as the sea surface temperature (SST) increases, the rate of outgoing infrared radiation at the top of the atmosphere also increases, as expected. Over the pacific warm pool where the SST exceeds 300 K the outgoing radiation emitted to space actually decreases with increasing SST, leading to a potentially unstable system. This behavior is a signature of the runaway greenhouse effect on Earth. However, the SST never exceeds 303K, thus the system has a natural cap which stops the runaway. According to Stefan-Boltzmann's law the amount of heat energy radiated by the Earth's surface is proportional to (T(sup 4)). However, if the planet has a substantial atmosphere, it can absorb all infrared radiation from the lower surface before the radiation penetrates into outer space. Thus, an instrument in space looking at the planet does not detect radiation from the surface. The radiation it sees comes from some level higher up. For the earth#s atmosphere the effective temperature (T(sub e)) has a value of 255 K corresponding to the middle troposphere, above most of the

The Potential for Volcanism and Tectonics on Extrasolar Terrestrial Planets

Science.gov (United States)

Quick, Lynnae C.; Roberge, Aki

2018-01-01

JWST and other next-generation space telescopes (e.g., LUVOIR, HabEx, & OST) will usher in a new era of exoplanet characterization that may lead to the identification of habitable, Earth-like worlds. Like the planets and moons in our solar system, the surfaces and interiors of terrestrial exoplanets may be shaped by volcanism and tectonics (Fu et al., 2010; van Summeren et al., 2011; Henning and Hurford, 2014). The magnitude and rate of occurrence of these dynamic processes can either facilitate or preclude the existence of habitable environments. Likewise, it has been suggested that detections of cryovolcanism on icy exoplanets, in the form of geyser-like plumes, could indicate the presence of subsurface oceans (Quick et al., 2017).The presence of volcanic and tectonic activity on solid exoplanets will be intimately linked to planet size and heat output in the form of radiogenic and/or tidal heating. In order to place bounds on the potential for such activity, we estimated the heat output of a variety of exoplanets observed by Kepler. We considered planets whose masses and radii range from 0.067 ME (super-Ganymede) to 8 ME (super-Earth), and 0.5 to 1.8 RE, respectively. These heat output estimates were then compared to those of planets, moons, and dwarf planets in our solar system for which we have direct evidence for the presence/absence of volcanic and tectonic activity. After exoplanet heating rates were estimated, depths to putative molten layers in their interiors were also calculated. For planets such as TRAPPIST-1h, whose densities, orbital parameters, and effective temperatures are consistent with the presence of significant amounts of H2O (Luger et al., 2017), these calculations reveal the depths to internal oceans which may serve as habitable niches beneath surface ice layers.

Constructing large scale SCI-based processing systems by switch elements

International Nuclear Information System (INIS)

Wu, B.; Kristiansen, E.; Skaali, B.; Bogaerts, A.; Divia, R.; Mueller, H.

1993-05-01

The goal of this paper is to study some of the design criteria for the switch elements to form the interconnection of large scale SCI-based processing systems. The approved IEEE standard 1596 makes it possible to couple up to 64K nodes together. In order to connect thousands of nodes to construct large scale SCI-based processing systems, one has to interconnect these nodes by switch elements to form different topologies. A summary of the requirements and key points of interconnection networks and switches is presented. Two models of the SCI switch elements are proposed. The authors investigate several examples of systems constructed for 4-switches with simulations and the results are analyzed. Some issues and enhancements are discussed to provide the ideas behind the switch design that can improve performance and reduce latency. 29 refs., 11 figs., 3 tabs

The effect of planets beyond the ice line on the accretion of volatiles by habitable-zone rocky planets

International Nuclear Information System (INIS)

Quintana, Elisa V.; Lissauer, Jack J.

2014-01-01

Models of planet formation have shown that giant planets have a large impact on the number, masses, and orbits of terrestrial planets that form. In addition, they play an important role in delivering volatiles from material that formed exterior to the snow line (the region in the disk beyond which water ice can condense) to the inner region of the disk where terrestrial planets can maintain liquid water on their surfaces. We present simulations of the late stages of terrestrial planet formation from a disk of protoplanets around a solar-type star and we include a massive planet (from 1 M ⊕ to 1 M J ) in Jupiter's orbit at ∼5.2 AU in all but one set of simulations. Two initial disk models are examined with the same mass distribution and total initial water content, but with different distributions of water content. We compare the accretion rates and final water mass fraction of the planets that form. Remarkably, all of the planets that formed in our simulations without giant planets were water-rich, showing that giant planet companions are not required to deliver volatiles to terrestrial planets in the habitable zone. In contrast, an outer planet at least several times the mass of Earth may be needed to clear distant regions of debris truncating the epoch of frequent large impacts. Observations of exoplanets from radial velocity surveys suggest that outer Jupiter-like planets may be scarce, therefore, the results presented here suggest that there may be more habitable planets residing in our galaxy than previously thought.

The effect of planets beyond the ice line on the accretion of volatiles by habitable-zone rocky planets

Energy Technology Data Exchange (ETDEWEB)

Quintana, Elisa V. [SETI Institute, 189 Bernardo Avenue, Suite 100, Mountain View, CA 94043 (United States); Lissauer, Jack J., E-mail: elisa.quintana@nasa.gov [Space Science and Astrobiology Division 245-3, NASA Ames Research Center, Moffett Field, CA 94035 (United States)

2014-05-01

Models of planet formation have shown that giant planets have a large impact on the number, masses, and orbits of terrestrial planets that form. In addition, they play an important role in delivering volatiles from material that formed exterior to the snow line (the region in the disk beyond which water ice can condense) to the inner region of the disk where terrestrial planets can maintain liquid water on their surfaces. We present simulations of the late stages of terrestrial planet formation from a disk of protoplanets around a solar-type star and we include a massive planet (from 1 M {sub ⊕} to 1 M {sub J}) in Jupiter's orbit at ∼5.2 AU in all but one set of simulations. Two initial disk models are examined with the same mass distribution and total initial water content, but with different distributions of water content. We compare the accretion rates and final water mass fraction of the planets that form. Remarkably, all of the planets that formed in our simulations without giant planets were water-rich, showing that giant planet companions are not required to deliver volatiles to terrestrial planets in the habitable zone. In contrast, an outer planet at least several times the mass of Earth may be needed to clear distant regions of debris truncating the epoch of frequent large impacts. Observations of exoplanets from radial velocity surveys suggest that outer Jupiter-like planets may be scarce, therefore, the results presented here suggest that there may be more habitable planets residing in our galaxy than previously thought.

KEPLER PLANETS: A TALE OF EVAPORATION

International Nuclear Information System (INIS)

Owen, James E.; Wu, Yanqin

2013-01-01

Inspired by the Kepler mission's planet discoveries, we consider the thermal contraction of planets close to their parent star, under the influence of evaporation. The mass-loss rates are based on hydrodynamic models of evaporation that include both X-ray and EUV irradiation. We find that only low mass planets with hydrogen envelopes are significantly affected by evaporation, with evaporation being able to remove massive hydrogen envelopes inward of ∼0.1 AU for Neptune-mass objects, while evaporation is negligible for Jupiter-mass objects. Moreover, most of the evaporation occurs in the first 100 Myr of stars' lives when they are more chromospherically active. We construct a theoretical population of planets with varying core masses, envelope masses, orbital separations, and stellar spectral types, and compare this population with the sizes and densities measured for low-mass planets, both in the Kepler mission and from radial velocity surveys. This exercise leads us to conclude that evaporation is the driving force of evolution for close-in Kepler planets. In fact, some 50% of the Kepler planet candidates may have been significantly eroded. Evaporation explains two striking correlations observed in these objects: a lack of large radius/low density planets close to the stars and a possible bimodal distribution in planet sizes with a deficit of planets around 2 R ⊕ . Planets that have experienced high X-ray exposures are generally smaller than this size, and those with lower X-ray exposures are typically larger. A bimodal planet size distribution is naturally predicted by the evaporation model, where, depending on their X-ray exposure, close-in planets can either hold on to hydrogen envelopes ∼0.5%-1% in mass or be stripped entirely. To quantitatively reproduce the observed features, we argue that not only do low-mass Kepler planets need to be made of rocky cores surrounded with hydrogen envelopes, but few of them should have initial masses above 20 M ⊕ and

KEPLER PLANETS: A TALE OF EVAPORATION

Energy Technology Data Exchange (ETDEWEB)

Owen, James E. [Canadian Institute for Theoretical Astrophysics, 60 St. George Street, Toronto, ON M5S 3H8 (Canada); Wu, Yanqin, E-mail: jowen@cita.utoronto.ca, E-mail: wu@astro.utoronto.ca [Department of Astronomy and Astrophysics, University of Toronto, Toronto, ON M5S 3H4 (Canada)

2013-10-01

Inspired by the Kepler mission's planet discoveries, we consider the thermal contraction of planets close to their parent star, under the influence of evaporation. The mass-loss rates are based on hydrodynamic models of evaporation that include both X-ray and EUV irradiation. We find that only low mass planets with hydrogen envelopes are significantly affected by evaporation, with evaporation being able to remove massive hydrogen envelopes inward of ∼0.1 AU for Neptune-mass objects, while evaporation is negligible for Jupiter-mass objects. Moreover, most of the evaporation occurs in the first 100 Myr of stars' lives when they are more chromospherically active. We construct a theoretical population of planets with varying core masses, envelope masses, orbital separations, and stellar spectral types, and compare this population with the sizes and densities measured for low-mass planets, both in the Kepler mission and from radial velocity surveys. This exercise leads us to conclude that evaporation is the driving force of evolution for close-in Kepler planets. In fact, some 50% of the Kepler planet candidates may have been significantly eroded. Evaporation explains two striking correlations observed in these objects: a lack of large radius/low density planets close to the stars and a possible bimodal distribution in planet sizes with a deficit of planets around 2 R{sub ⊕}. Planets that have experienced high X-ray exposures are generally smaller than this size, and those with lower X-ray exposures are typically larger. A bimodal planet size distribution is naturally predicted by the evaporation model, where, depending on their X-ray exposure, close-in planets can either hold on to hydrogen envelopes ∼0.5%-1% in mass or be stripped entirely. To quantitatively reproduce the observed features, we argue that not only do low-mass Kepler planets need to be made of rocky cores surrounded with hydrogen envelopes, but few of them should have initial masses above

Classifying Planets: Nature vs. Nurture

Science.gov (United States)

Beichman, Charles A.

2009-05-01

The idea of a planet was so simple when we learned about the solar system in elementary school. Now students and professional s alike are faced with confusing array of definitions --- from "Brown Dwarfs” to "Super Jupiters", from "Super Earths” to "Terrestrial Planets", and from "Planets” to "Small, Sort-of Round Things That Aren't Really Planets". I will discuss how planets might be defined by how they formed, where they are found, or by the life they might support.

GeoSciML v3.0 - a significant upgrade of the CGI-IUGS geoscience data model

Science.gov (United States)

Raymond, O.; Duclaux, G.; Boisvert, E.; Cipolloni, C.; Cox, S.; Laxton, J.; Letourneau, F.; Richard, S.; Ritchie, A.; Sen, M.; Serrano, J.-J.; Simons, B.; Vuollo, J.

2012-04-01

GeoSciML version 3.0 (http://www.geosciml.org), released in late 2011, is the latest version of the CGI-IUGS* Interoperability Working Group geoscience data interchange standard. The new version is a significant upgrade and refactoring of GeoSciML v2 which was released in 2008. GeoSciML v3 has already been adopted by several major international interoperability initiatives, including OneGeology, the EU INSPIRE program, and the US Geoscience Information Network, as their standard data exchange format for geoscience data. GeoSciML v3 makes use of recently upgraded versions of several Open Geospatial Consortium (OGC) and ISO data transfer standards, including GML v3.2, SWE Common v2.0, and Observations and Measurements v2 (ISO 19156). The GeoSciML v3 data model has been refactored from a single large application schema with many packages, into a number of smaller, but related, application schema modules with individual namespaces. This refactoring allows the use and future development of modules of GeoSciML (eg; GeologicUnit, GeologicStructure, GeologicAge, Borehole) in smaller, more manageable units. As a result of this refactoring and the integration with new OGC and ISO standards, GeoSciML v3 is not backwardly compatible with previous GeoSciML versions. The scope of GeoSciML has been extended in version 3.0 to include new models for geomorphological data (a Geomorphology application schema), and for geological specimens, geochronological interpretations, and metadata for geochemical and geochronological analyses (a LaboratoryAnalysis-Specimen application schema). In addition, there is better support for borehole data, and the PhysicalProperties model now supports a wider range of petrophysical measurements. The previously used CGI_Value data type has been superseded in favour of externally governed data types provided by OGC's SWE Common v2 and GML v3.2 data standards. The GeoSciML v3 release includes worked examples of best practice in delivering geochemical

Spinal Cord Injury Community Survey: Understanding the Needs of Canadians with SCI.

Science.gov (United States)

Noreau, Luc; Noonan, Vanessa K; Cobb, John; Leblond, Jean; Dumont, Frédéric S

2014-01-01

There is a lack of literature regarding service needs of people with SCI living in the community. Better assessment of expressed and met and unmet needs would help in the development of effective service delivery. From a national SCI Community Survey in Canada, the aim was to identify the most critical service needs of people living in the community at least 1 year post discharge from rehabilitation and the support they received to meet their needs. Data were collected mainly through a secure Web site and encompassed demographics, personal and household income, an SCI severity measure, and an SCI community needs measure containing information on 13 SCI-related needs. A total of 1,549 persons with SCI (traumatic lesion, n = 1,137; nontraumatic lesion, n = 412) across Canada completed the survey. Most critical needs for community integration were expressed by a substantial proportion of survey participants, but significantly more expressed and met needs were reported by persons with a traumatic than a nontraumatic lesion. Personal and environmental characteristics influenced the probability of expressing and meeting needs (eg, severity of injury and household income). Help and support to meet expressed needs were received from government agencies, community organizations, and friends or family. Better assessment of expressed and met or unmet needs for services remains a challenge but will serve as a tool to optimize service delivery in the community. Environmental barriers to services, particularly the process of getting needs met and associated costs, remain an issue that requires a reconsideration of some aspects of access to services.

Electromagnetic behaviour of the earth and planets

International Nuclear Information System (INIS)

McCarthy, A.J.

2002-01-01

Forecast problems of global warming, rising sea-levels, UV enhancement, and solar disruptions of power grids and satellite communications, have been widely discussed. Added to these calamities is the steady decay of the Earth's magnetic radiation shield against high energy particles. A system of solar-induced aperiodic electromagnetic resonances, referred to here as the Debye resonances, is resurrected as the preferred basis for describing the electromagnetic behaviour of the Earth and planets. Debye's two basic solutions to the spherical vector wave equation provide foundations for electromagnetic modes of the terrestrial and gaseous planets respectively in contrast with the separate electric and magnetic approaches usually taken. For those engaged in radiation protection issues, this paper provides the first published account of how the Sun apparently triggers an Earth magnetic shield against its own harmful radiation. Disturbances from the Sun - which are random in terms of polarity, polarisation, amplitude, and occurrence - are considered here to trigger the Debye modes and generate observed planetary electric and magnetic fields. Snapping or reconnection of solar or interplanetary field lines, acting together with the newly conceived magnetospheric transmission lines of recent literature, is suspected as the excitation mechanism. Virtual replacement of free space by plasma, places the electromagnetic behaviour of the Earth and planets under greatly enhanced control from the Sun. From a radiation protection viewpoint, modal theory based on solar-terrestrial coupling provides a new insight into the origin of the Earth's magnetic radiation shield, greater understanding of which is essential to development of global cosmic radiation protection strategies. Should man-made influences unduly increase conductivities of the Earth's magnetosphere, planet Earth could be left with no magnetic radiation shield whatsoever. Copyright (2002) Australasian Radiation Protection

Planet formation in Binaries

OpenAIRE

Thebault, Ph.; Haghighipour, N.

2014-01-01

Spurred by the discovery of numerous exoplanets in multiple systems, binaries have become in recent years one of the main topics in planet formation research. Numerous studies have investigated to what extent the presence of a stellar companion can affect the planet formation process. Such studies have implications that can reach beyond the sole context of binaries, as they allow to test certain aspects of the planet formation scenario by submitting them to extreme environments. We review her...

GeoSciML version 3: A GML application for geologic information

Science.gov (United States)

International Union of Geological Sciences., I. C.; Richard, S. M.

2011-12-01

After 2 years of testing and development, XML schema for GeoSciML version 3 are now ready for application deployment. GeoSciML draws from many geoscience data modelling efforts to establish a common suite of feature types to represent information associated with geologic maps (materials, structures, and geologic units) and observations including structure data, samples, and chemical analyses. After extensive testing and use case analysis, in December 2008 the CGI Interoperability Working Group (IWG) released GeoSciML 2.0 as an application schema for basic geological information. GeoSciML 2.0 is in use to deliver geologic data by the OneGeology Europe portal, the Geological Survey of Canada Groundwater Information Network (wet GIN), and the Auscope Mineral Resources portal. GeoSciML to version 3.0 is updated to OGC Geography Markup Language v3.2, re-engineered patterns for association of element values with controlled vocabulary concepts, incorporation of ISO19156 Observation and Measurement constructs for representing numeric and categorical values and for representing analytical data, incorporation of EarthResourceML to represent mineral occurrences and mines, incorporation of the GeoTime model to represent GSSP and stratigraphic time scale, and refactoring of the GeoSciML namespace to follow emerging ISO practices for decoupling of dependencies between standardized namespaces. These changes will make it easier for data providers to link to standard vocabulary and registry services. The depth and breadth of GeoSciML remains largely unchanged, covering the representation of geologic units, earth materials and geologic structures. ISO19156 elements and patterns are used to represent sampling features such as boreholes and rock samples, as well as geochemical and geochronologic measurements. Geologic structures include shear displacement structures (brittle faults and ductile shears), contacts, folds, foliations, lineations and structures with no preferred

Study Protocol of the International Spinal Cord Injury (InSCI) Community Survey

NARCIS (Netherlands)

Gross-Hemmi, Mirja H.; Post, Marcel W. M.; Ehrmann, Cristina; Fekete, Christine; Hasnan, Nazirah; Middleton, James W.; Reinhardt, Jan D.; Strom, Vegard; Stucki, Gerold

Objective: The Learning Health System for Spinal Cord Injury (LHS-SCI) is an initiative embedded in the World Health Organization's (WHO's) Global Disability Plan and requires the statistical collection of data on the lived experience of persons with SCI to consequently formulate recommendations and

Planetary and Space Simulation Facilities (PSI) at DLR

Science.gov (United States)

Panitz, Corinna; Rabbow, E.; Rettberg, P.; Kloss, M.; Reitz, G.; Horneck, G.

2010-05-01

organisms in space and will contribute to the understanding of the organic chemistry processes in space, the biological adaptation strategies to extreme conditions, e.g. on early Earth and Mars, and the distribution of life beyond its planet of origin The results gained during the simulation experiments demonstrated mission preparation as a basic requirement for successful and significant results of every space flight experiment. Hence, the Mission preparation program that was performed in the context of the space missions EXPOSE-E and EXPOSE-R proofed the outstanding importance and accentuated need for ground based experiments before and during a space mission. The facilities are also necessary for the performance of the ground control experiment during the mission, the so-called Mission Simulation Test (MST) under simulated space conditions, by parallel exposure of samples to simulated space parameters according to flight data received by telemetry. Finally the facilities also provide the possibility to simulate the surface and climate conditions of the planet Mars. In this way they offer the possibility to investigate under simulated Mars conditions the chances for development of life on Mars and to gain previous knowledge for the search for life on today's Mars and in this context especially the parameters for a manned mission to Mars. References [1] Rabbow E, Rettberg P, Panitz C, Drescher J, Horneck G, Reitz G (2005) SSIOUX - Space Simulation for Investigating Organics, Evolution and Exobiology, Adv. Space Res. 36 (2) 297-302, doi:10.1016/j.asr.2005.08.040Aman, A. and Bman, B. (1997) JGR, 90,1151-1154. [2] Fekete A, Modos K, Hegedüs M, Kovacs G, Ronto Gy, Peter A, Lammer H, Panitz C (2005) DNA Damage under simulated extraterrestrial conditions in bacteriophage T7 Adv. Space Res. 305-310Aman, A. et al. (1997) Meteoritics & Planet. Sci., 32,A74. [3] Cockell Ch, Schuerger AC, Billi D., Friedmann EI, Panitz C (2005) Effects of a Simulated Martian UV Flux on the

Current status of SCI and SCIE publications in the field of radiation oncology in Korea

International Nuclear Information System (INIS)

Kang, Jin Oh

2007-01-01

To investigate current status of SCI (Science Citation Index) and SCI Expanded publication of Korean radiation oncologists. Published SCI and SCIE articles the conditions of first author's address as 'Korea' and 'Radiation Oncology' or 'Therapeutic Radiology' were searched from Pubmed database. From 1990 to 2006, 146 SCI articles and 32 SCIE articles were published. Most frequently published journal was international Journal of Radiation Oncology Biology Physics, where 56 articles were found. Articles with 30 or more citations were only five and 10 or more citations were 26. Yonsei University, which had 57 published articles, was the top among 19 affiliations which had one or more SCI and SCIE articles. Authors with five or more articles were 9 and Seong J. of Yonsei University was the top with 19 articles. The investigations showed disappointing results. The members of Korean Society of Radiation Oncologists must consider a strategy to increase SCI and SCIE publications

Targeting Translational Successes through CANSORT-SCI: Using Pet Dogs To Identify Effective Treatments for Spinal Cord Injury.

Science.gov (United States)

Moore, Sarah A; Granger, Nicolas; Olby, Natasha J; Spitzbarth, Ingo; Jeffery, Nick D; Tipold, Andrea; Nout-Lomas, Yvette S; da Costa, Ronaldo C; Stein, Veronika M; Noble-Haeusslein, Linda J; Blight, Andrew R; Grossman, Robert G; Basso, D Michele; Levine, Jonathan M

2017-06-15

Translation of therapeutic interventions for spinal cord injury (SCI) from laboratory to clinic has been historically challenging, highlighting the need for robust models of injury that more closely mirror the human condition. The high prevalence of acute, naturally occurring SCI in pet dogs provides a unique opportunity to evaluate expeditiously promising interventions in a population of animals that receive diagnoses and treatment clinically in a manner similar to persons with SCI, while adhering to National Institutes of Health guidelines for scientific rigor and transparent reporting. In addition, pet dogs with chronic paralysis are often maintained long-term by their owners, offering a similarly unique population for study of chronic SCI. Despite this, only a small number of studies have used the clinical dog model of SCI. The Canine Spinal Cord Injury Consortium (CANSORT-SCI) was recently established by a group of veterinarians and basic science researchers to promote the value of the canine clinical model of SCI. The CANSORT-SCI group held an inaugural meeting November 20 and 21, 2015 to evaluate opportunities and challenges to the use of pet dogs in SCI research. Key challenges identified included lack of familiarity with the model among nonveterinary scientists and questions about how and where in the translational process the canine clinical model would be most valuable. In light of these, we review the natural history, outcome, and available assessment tools associated with canine clinical SCI with emphasis on their relevance to human SCI and the translational process.

Homogeneous Studies of Transiting Extrasolar Planets: Current Status and Future Plans

Science.gov (United States)

Taylor, John

2011-09-01

We now know of over 500 planets orbiting stars other than our Sun. The jewels in the crown are the transiting planets, for these are the only ones whose masses and radii are measurable. They are fundamental for our understanding of the formation, evolution, structure and atmospheric properties of extrasolar planets. However, their characterization is not straightforward, requiring extremely high-precision photometry and spectroscopy as well as input from theoretical stellar models. I summarize the motivation and current status of a project to measure the physical properties of all known transiting planetary systems using homogeneous techniques (Southworth 2008, 2009, 2010, 2011 in preparation). Careful attention is paid to the treatment of limb darkening, contaminating light, correlated noise, numerical integration, orbital eccentricity and orientation, systematic errors from theoretical stellar models, and empirical constraints. Complete error budgets are calculated for each system and can be used to determine which type of observation would be most useful for improving the parameter measurements. Known correlations between the orbital periods, masses, surface gravities, and equilibrium temperatures of transiting planets can be explored more safely due to the homogeneity of the properties. I give a sneak preview of Homogeneous Studies Paper 4, which includes the properties of thirty transiting planetary systems observed by the CoRoT, Kepler and Deep Impact space missions. Future opportunities are discussed, plus remaining problems with our understanding of transiting planets. I acknowledge funding from the UK STFC in the form of an Advanced Fellowship.

PASTIS: Bayesian extrasolar planet validation - I. General framework, models, and performance

Science.gov (United States)

Díaz, R. F.; Almenara, J. M.; Santerne, A.; Moutou, C.; Lethuillier, A.; Deleuil, M.

2014-06-01

A large fraction of the smallest transiting planet candidates discovered by the Kepler and CoRoT space missions cannot be confirmed by a dynamical measurement of the mass using currently available observing facilities. To establish their planetary nature, the concept of planet validation has been advanced. This technique compares the probability of the planetary hypothesis against that of all reasonably conceivable alternative false positive (FP) hypotheses. The candidate is considered as validated if the posterior probability of the planetary hypothesis is sufficiently larger than the sum of the probabilities of all FP scenarios. In this paper, we present PASTIS, the Planet Analysis and Small Transit Investigation Software, a tool designed to perform a rigorous model comparison of the hypotheses involved in the problem of planet validation, and to fully exploit the information available in the candidate light curves. PASTIS self-consistently models the transit light curves and follow-up observations. Its object-oriented structure offers a large flexibility for defining the scenarios to be compared. The performance is explored using artificial transit light curves of planets and FPs with a realistic error distribution obtained from a Kepler light curve. We find that data support the correct hypothesis strongly only when the signal is high enough (transit signal-to-noise ratio above 50 for the planet case) and remain inconclusive otherwise. PLAnetary Transits and Oscillations of stars (PLATO) shall provide transits with high enough signal-to-noise ratio, but to establish the true nature of the vast majority of Kepler and CoRoT transit candidates additional data or strong reliance on hypotheses priors is needed.

Probing clouds in planets with a simple radiative transfer model: the Jupiter case

International Nuclear Information System (INIS)

Mendikoa, Iñigo; Pérez-Hoyos, Santiago; Sánchez-Lavega, Agustín

2012-01-01

Remote sensing of planets evokes using expensive on-orbit satellites and gathering complex data from space. However, the basic properties of clouds in planetary atmospheres can be successfully estimated with small telescopes even from an urban environment using currently available and affordable technology. This makes the process accessible for undergraduate students while preserving most of the physics and mathematics involved. This paper presents the methodology for carrying out a photometric study of planetary atmospheres, focused on the planet Jupiter. The method introduces the basics of radiative transfer in planetary atmospheres, some notions on inverse problem theory and the fundamentals of planetary photometry. As will be shown, the procedure allows the student to derive the spectral reflectivity and top altitude of clouds from observations at different wavelengths by applying a simple but enlightening ‘reflective layer model’. In this way, the planet's atmospheric structure is estimated by students as an inverse problem from the observed photometry. Web resources are also provided to help those unable to obtain telescopic observations of the planets. (paper)

Probing clouds in planets with a simple radiative transfer model: the Jupiter case

Science.gov (United States)

Mendikoa, Iñigo; Pérez-Hoyos, Santiago; Sánchez-Lavega, Agustín

2012-11-01

Remote sensing of planets evokes using expensive on-orbit satellites and gathering complex data from space. However, the basic properties of clouds in planetary atmospheres can be successfully estimated with small telescopes even from an urban environment using currently available and affordable technology. This makes the process accessible for undergraduate students while preserving most of the physics and mathematics involved. This paper presents the methodology for carrying out a photometric study of planetary atmospheres, focused on the planet Jupiter. The method introduces the basics of radiative transfer in planetary atmospheres, some notions on inverse problem theory and the fundamentals of planetary photometry. As will be shown, the procedure allows the student to derive the spectral reflectivity and top altitude of clouds from observations at different wavelengths by applying a simple but enlightening ‘reflective layer model’. In this way, the planet's atmospheric structure is estimated by students as an inverse problem from the observed photometry. Web resources are also provided to help those unable to obtain telescopic observations of the planets.

Trapping planets in an evolving protoplanetary disk: preferred time, locations and planet mass

OpenAIRE

Baillié, Kévin; Charnoz, Sébastien; Pantin, Éric

2016-01-01

Planet traps are necessary to prevent forming planets from falling onto their host star by type I migration. Surface mass density and temperature gradient irregularities favor the apparition of traps and deserts. Such features are found at the dust sublimation lines and heat transition barriers. We study how planets may remain trapped or escape as they grow and as the disk evolves. We model the temporal viscous evolution of a protoplanetary disk by coupling its dynamics, thermodynamics, geome...

Useful Method To Optimize The Rehabilitation Effort At A SCI Rehabilitation Centre

DEFF Research Database (Denmark)

Steensgaard, Randi; Dahl Hoffmann, Dorte

“Useful Method To Optimize The Rehabilitation Effort At A SCI Rehabilitation Centre” The Nordic Spinal Cord Society (NoSCoS) Meeting, Trondheim......“Useful Method To Optimize The Rehabilitation Effort At A SCI Rehabilitation Centre” The Nordic Spinal Cord Society (NoSCoS) Meeting, Trondheim...

Open System Architecture design for planet surface systems

Science.gov (United States)

Petri, D. A.; Pieniazek, L. A.; Toups, L. D.

1992-01-01

The Open System Architecture is an approach to meeting the needs for flexibility and evolution of the U.S. Space Exploration Initiative program of the manned exploration of the solar system and its permanent settlement. This paper investigates the issues that future activities of the planet exploration program must confront, defines the basic concepts that provide the basis for establishing an Open System Architecture, identifies the appropriate features of such an architecture, and discusses examples of Open System Architectures.

THE PAN-PACIFIC PLANET SEARCH. II. CONFIRMATION OF A TWO-PLANET SYSTEM AROUND HD 121056

Energy Technology Data Exchange (ETDEWEB)

Wittenmyer, Robert A.; Tinney, C. G. [School of Physics, University of New South Wales, Sydney, NSW 2052 (Australia); Wang, Liang [Key Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences, A20 Datun Road, Chaoyang District, Beijing 100012 (China); Liu, Fan [Research School of Astronomy and Astrophysics, Australian National University, Cotter Road, Weston Creek, ACT 2611 (Australia); Horner, Jonathan [Australian Centre for Astrobiology, University of New South Wales, Sydney, NSW 2052 (Australia); Endl, Michael [McDonald Observatory, University of Texas at Austin, 1 University Station C1400, Austin, TX 78712 (United States); Johnson, John Asher [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States); Carter, B. D., E-mail: rob@unsw.edu.au [Computational Engineering and Science Research Centre, University of Southern Queensland, Toowoomba, Queensland 4350 (Australia)

2015-02-10

Precise radial velocities from the Anglo-Australian Telescope (AAT) confirm the presence of a rare short-period planet around the K0 giant HD 121056. An independent two-planet solution using the AAT data shows that the inner planet has P = 89.1 ± 0.1 days, and m sin i = 1.35 ± 0.17 M{sub Jup}. These data also confirm the planetary nature of the outer companion, with m sin i = 3.9 ± 0.6 M{sub Jup} and a = 2.96 ± 0.16 AU. HD 121056 is the most-evolved star to host a confirmed multiple-planet system, and is a valuable example of a giant star hosting both a short-period and a long-period planet.

THE PAN-PACIFIC PLANET SEARCH. II. CONFIRMATION OF A TWO-PLANET SYSTEM AROUND HD 121056

International Nuclear Information System (INIS)

Wittenmyer, Robert A.; Tinney, C. G.; Wang, Liang; Liu, Fan; Horner, Jonathan; Endl, Michael; Johnson, John Asher; Carter, B. D.

2015-01-01

Precise radial velocities from the Anglo-Australian Telescope (AAT) confirm the presence of a rare short-period planet around the K0 giant HD 121056. An independent two-planet solution using the AAT data shows that the inner planet has P = 89.1 ± 0.1 days, and m sin i = 1.35 ± 0.17 M Jup . These data also confirm the planetary nature of the outer companion, with m sin i = 3.9 ± 0.6 M Jup and a = 2.96 ± 0.16 AU. HD 121056 is the most-evolved star to host a confirmed multiple-planet system, and is a valuable example of a giant star hosting both a short-period and a long-period planet

New Cosmic Horizons: Space Astronomy from the V2 to the Hubble Space Telescope

Science.gov (United States)

Leverington, David

2001-02-01

Preface; 1. The sounding rocket era; 2. The start of the space race; 3. Initial exploration of the Solar System; 4. Lunar exploration; 5. Mars and Venus; early results; 6. Mars and Venus; the middle period; 7. Venus, Mars and cometary spacecraft post-1980; 8. Early missions to the outer planets; 9. The Voyager missions to the outer planets; 10. The Sun; 11. Early spacecraft observations of non-solar system sources; 12. A period of rapid growth; 13. The high energy astronomy observatory programme; 14. IUE, IRAS and Exosat - spacecraft for the early 1980s; 15. Hiatus; 16. Business as usual; 17. The Hubble Space Telescope.

Spectral fingerprints of Earth-like planets around FGK stars.

Science.gov (United States)

Rugheimer, Sarah; Kaltenegger, Lisa; Zsom, Andras; Segura, Antígona; Sasselov, Dimitar

2013-03-01

We present model atmospheres for an Earth-like planet orbiting the entire grid of main sequence FGK stars with effective temperatures ranging from Teff=4250 K to Teff=7000 K in 250 K intervals. We have modeled the remotely detectable spectra of Earth-like planets for clear and cloudy atmospheres at the 1 AU equivalent distance from the VIS to IR (0.4 to 20 μm) to compare detectability of features in different wavelength ranges in accordance with the James Webb Space Telescope and future design concepts to characterize exo-Earths. We have also explored the effect of the stellar UV levels as well as spectral energy distribution on a terrestrial atmosphere, concentrating on detectable atmospheric features that indicate habitability on Earth, namely, H2O, O3, CH4, N2O, and CH3Cl. The increase in UV dominates changes of O3, OH, CH4, N2O, and CH3Cl, whereas the increase in stellar temperature dominates changes in H2O. The overall effect as stellar effective temperatures and corresponding UV increase is a lower surface temperature of the planet due to a bigger part of the stellar flux being reflected at short wavelengths, as well as increased photolysis. Earth-like atmosphere models show more O3 and OH but less stratospheric CH4, N2O, CH3Cl, and tropospheric H2O (but more stratospheric H2O) with increasing effective temperature of main sequence stars. The corresponding detectable spectral features, on the other hand, show different detectability depending on the wavelength observed. We concentrate on directly imaged planets here as a framework to interpret future light curves, direct imaging, and secondary eclipse measurements of atmospheres of terrestrial planets in the habitable zone at varying orbital positions.

Mapping the Region in the Nearest Star System to Search for Habitable Planets

Science.gov (United States)

Lissauer, Jack J.; Quarles, B.

2015-01-01

Circumstellar planets within the alpha Centauri AB star system have been suggested through formation models and recent observations, and ACESat (Belikov et al. AAS Meeting #225, #311.01, 2015) is a proposed space mission designed to directly image Earth-sized planets in the habitable zones of both of these stars. The alpha Centauri system is billions of years old, so planets are only expected to be found in regions where their orbits are long-lived. We evaluate the extent of the regions within the alpha Centauri AB star system where small planets are able to orbit for billion-year timescales and we map the positions in the sky plane where planets on stable orbits about either stellar component may appear. We confirm the qualitative results of Wiegert & Holman (Astron. J. 113, 1445, 1997) regarding the approximate size of the regions of stable orbits, which are larger for retrograde orbits relative to the binary than for prograde orbits. Additionally, we find that mean motion resonances with the binary orbit leave an imprint on the limits of orbital stability, and the effects of the Lidov-Kozai mechanism are also readily apparent. Overall, orbits in the habitable zones near the plane of the binary are stable, whereas high-inclination orbits are short-lived.

Extrasolar Planets in the Classroom

Science.gov (United States)

George, Samuel J.

2011-01-01

The field of extrasolar planets is still, in comparison with other astrophysical topics, in its infancy. There have been about 300 or so extrasolar planets detected and their detection has been accomplished by various different techniques. Here we present a simple laboratory experiment to show how planets are detected using the transit technique.…

Not just quantity: gluteus maximus muscle characteristics in able-bodied and SCI individuals--implications for tissue viability.

Science.gov (United States)

Wu, Gary A; Bogie, Kath M

2013-08-01

Some individuals with spinal cord injury (SCI) remain pressure ulcer (PU) free whilst others experience a recurring cycle of tissue breakdown. Detailed analysis of gluteal muscle characteristics may provide insights to local tissue viability variability. The study hypothesis was that SCI individuals have altered muscle composition compared to able-bodied (AB). Ten AB and ten SCI received a supine pelvic CT scan, with contrast. Cross-sectional area (CSA) and overall muscle volume were derived using image analysis. Gluteal muscle tissue type was classified at the S2/S3 sacral vertebrae midpoint, the superior greater trochanters margin (GT) and the inferior ischial tuberosities margin (IT) using the linear transformation Hounsfield Unit scale. SCI gluteal CSA was less than for AB throughout the muscle, with the greatest relative atrophy at the IT (48%). Average AB gluteal volume was nearly double SCI. Eight SCI had over 20% infiltrative adipose tissue, three with over 50%. SCI gluteal CSA and intramuscular fat infiltration were significantly negatively correlated (p SCI IT axial slices showed less lean muscle and higher intramuscular fat infiltration than more proximally (p SCI gluteal muscle characteristics were indicative of impaired tissue viability. SCI disuse muscle atrophy was anticipated; the analytic approach further indicated that intramuscular atrophy was not uniform. SCI muscle composition showed increased proportions of both low density muscle and adipose tissue. CT scan with contrast is effective for gluteal muscle characterization. This assessment technique may contribute to determination of personalized risk for PU development and other secondary complications. Published by Elsevier Ltd.

Early Hydrodynamic Escape Limits Rocky Planets to Less Than or Equal to 1.6 Earth Radii

Science.gov (United States)

Lehmer, O. R.; Catling, D. C.

2017-01-01

In the past decade thousands of exoplanet candidates and hundreds of confirmed exoplanets have been found. For sub-Neptune-sized planets, those less than approx. 10 Earth masses, we can separate planets into two broad categories: predominantly rocky planets, and gaseous planets with thick volatile sheaths. Observations and subsequent analysis of these planets show that rocky planets are only found with radii less than approx. 1.6 Earth radii. No rocky planet has yet been found that violates this limit. We propose that hydrodynamic escape of hydrogen rich protoatmospheres, accreted by forming planets, explains the limit in rocky planet size. Following the hydrodynamic escape model employed by Luger et al. (2015), we modelled the XUV driven escape from young planets (less than approx.100 Myr in age) around a Sun-like star. With a simple, first-order model we found that the rocky planet radii limit occurs consistently at approx. 1.6 Earth radii across a wide range of plausible parameter spaces. Our model shows that hydrodynamic escape can explain the observed cutoff between rocky and gaseous planets. Fig. 1 shows the results of our model for rocky planets between 0.5 and 10 Earth masses that accrete 3 wt. % H2/He during formation. The simulation was run for 100 Myr, after that time the XUV flux drops off exponentially and hydrodynamic escape drops with it. A cutoff between rocky planets and gaseous ones is clearly seen at approx. 1.5-1.6 Earth radii. We are only interested in the upper size limit for rocky planets. As such, we assumed pure hydrogen atmospheres and the highest possible isothermal atmospheric temperatures, which will produce an upper limit on the hydrodynamic loss rate. Previous work shows that a reasonable approximation for an upper temperature limit in a hydrogen rich protoatmosphere is 2000-3000 K, consistent with our assumptions. From these results, we propose that the observed dichotomy between mini-Neptunes and rocky worlds is simply explained by

Extrasolar planets searches today and tomorrow

CERN Multimedia

2000-01-01

So far the searches for extrasolar planets have found 40 planetary companions orbiting around nearby stars. In December 1999 a transit has been observed for one of them, providing the first independent confirmation of the reality of close-in planets as well as a measurement of its density. The techniques used to detect planets are limited and the detection threshold is biased but a first picture of the planet diversity and distribution emerges. Results of the search for extra-solar planets and their impacts on planetary formation will be reviewed. Future instruments are foreseen to detect Earth-like planets and possible signatures of organic activity. An overview of these future projects will be presented and more particularly the Darwin-IRSI mission studied by ESA for Horizon 2015.

Stable Hydrogen-rich Atmospheres of Young Rocky Planets

Science.gov (United States)

Zahnle, K. J.; Catling, D. C.; Gacesa, M.

2016-12-01

SourceURL:file://localhost/Volumes/Lexar/Zahnle_AGU_2016.docx Understanding hydrogen escape is essential to understanding the limits to habitability, both for liquid water where the Sun is bright, but also to assess the true potential of H2 as a greenhouse gas where the Sun is faint. Hydrogen-rich primary atmospheres of Earth-like planets can result either from gravitational capture of solar nebular gases (with helium), or from impact shock processing of a wide variety of volatile-rich planetesimals (typically accompanied by H2O, CO2, and under the right circumstances, CH4). Most studies of hydrogen escape from planets focus on determining how fast the hydrogen escapes. In general this requires solving hydrodynamic equations that take into account the acceleration of hydrogen through a critical transonic point and an energy budget that should include radiative heating and cooling, thermal conduction, the work done in lifting the hydrogen against gravity, and the residual heat carried by the hydrogen as it leaves. But for planets from which hydrogen escape is modest or insignificant, the atmosphere can be approximated as hydrostatic, which is much simpler, and for which a relatively full-featured treatment of radiative cooling by embedded molecules, atoms, and ions such as CO2 and H3+ is straightforward. Previous work has overlooked the fact that the H2 molecule is extremely efficient at exciting non-LTE CO2 15 micron emission, and thus that radiative cooling can be markedly more efficient when H2 is abundant. We map out the region of phase space in which terrestrial planets keep hydrogen-rich atmospheres, which is what we actually want to know for habitability. We will use this framework to reassess Tian et al's (Science 308, pp. 1014-1017, 2005) hypothesis that H2-rich atmospheres may have been rather long-lived on Earth itself. Finally, we will address the empirical observation that rocky planets with thin or negligible atmospheres are rarely or never bigger than

Detection of Abnormal Muscle Activations during Walking Following Spinal Cord Injury (SCI)

Science.gov (United States)

Wang, Ping; Low, K. H.; McGregor, Alison H.; Tow, Adela

2013-01-01

In order to identify optimal rehabilitation strategies for spinal cord injury (SCI) participants, assessment of impaired walking is required to detect, monitor and quantify movement disorders. In the proposed assessment, ten healthy and seven SCI participants were recruited to perform an over-ground walking test at slow walking speeds. SCI…

GeoSciGraph: An Ontological Framework for EarthCube Semantic Infrastructure

Science.gov (United States)

Gupta, A.; Schachne, A.; Condit, C.; Valentine, D.; Richard, S.; Zaslavsky, I.

2015-12-01

The CINERGI (Community Inventory of EarthCube Resources for Geosciences Interoperability) project compiles an inventory of a wide variety of earth science resources including documents, catalogs, vocabularies, data models, data services, process models, information repositories, domain-specific ontologies etc. developed by research groups and data practitioners. We have developed a multidisciplinary semantic framework called GeoSciGraph semantic ingration of earth science resources. An integrated ontology is constructed with Basic Formal Ontology (BFO) as its upper ontology and currently ingests multiple component ontologies including the SWEET ontology, GeoSciML's lithology ontology, Tematres controlled vocabulary server, GeoNames, GCMD vocabularies on equipment, platforms and institutions, software ontology, CUAHSI hydrology vocabulary, the environmental ontology (ENVO) and several more. These ontologies are connected through bridging axioms; GeoSciGraph identifies lexically close terms and creates equivalence class or subclass relationships between them after human verification. GeoSciGraph allows a community to create community-specific customizations of the integrated ontology. GeoSciGraph uses the Neo4J,a graph database that can hold several billion concepts and relationships. GeoSciGraph provides a number of REST services that can be called by other software modules like the CINERGI information augmentation pipeline. 1) Vocabulary services are used to find exact and approximate terms, term categories (community-provided clusters of terms e.g., measurement-related terms or environmental material related terms), synonyms, term definitions and annotations. 2) Lexical services are used for text parsing to find entities, which can then be included into the ontology by a domain expert. 3) Graph services provide the ability to perform traversal centric operations e.g., finding paths and neighborhoods which can be used to perform ontological operations like

Habitable Planets for Man

National Research Council Canada - National Science Library

Dole, Stephen H

2007-01-01

..., and discusses how to search for habitable planets. Interestingly for our time, he also gives an appraisal of the earth as a planet and describes how its habitability would be changed if some of its basic properties were altered...

The circumstances of minor planet discovery

International Nuclear Information System (INIS)

Pilcher, F.

1989-01-01

The circumstances of discoveries of minor planets are presented in tabular form. Complete data are given for planets 2125-4044, together with notes pertaining to these planets. Information in the table includes the permanent number; the official name; for planets 330 and forward, the table includes the provisional designation attached to the discovery apparition and the year, month, the day of discovery, and the discovery place

The accretion of migrating giant planets

Science.gov (United States)

Dürmann, Christoph; Kley, Wilhelm

2017-02-01

Aims: Most studies concerning the growth and evolution of massive planets focus either on their accretion or their migration only. In this work we study both processes concurrently to investigate how they might mutually affect one another. Methods: We modeled a two-dimensional disk with a steady accretion flow onto the central star and embedded a Jupiter mass planet at 5.2 au. The disk is locally isothermal and viscosity is modeled using a constant α. The planet is held on a fixed orbit for a few hundred orbits to allow the disk to adapt and carve a gap. After this period, the planet is released and free to move according to the gravitational interaction with the gas disk. The mass accretion onto the planet is modeled by removing a fraction of gas from the inner Hill sphere, and the removed mass and momentum can be added to the planet. Results: Our results show that a fast migrating planet is able to accrete more gas than a slower migrating planet. Utilizing a tracer fluid we analyzed the origin of the accreted gas originating predominantly from the inner disk for a fast migrating planet. In the case of slower migration, the fraction of gas from the outer disk increases. We also found that even for very high accretion rates, in some cases gas crosses the planetary gap from the inner to the outer disk. Our simulations show that the crossing of gas changes during the migration process as the migration rate slows down. Therefore, classical type II migration where the planet migrates with the viscous drift rate and no gas crosses the gap is no general process but may only occur for special parameters and at a certain time during the orbital evolution of the planet.

Mirroring of fibre ends for the LHCb SciFi project

CERN Document Server

Joram, Christian

2014-01-01

The relatively low light yields for tracks close to the midplane (y=0) of the SciFi tracker, in particular after radiation damage due to ionizing radiation, suggests to mirror the fibre ends. This note describes a set of tests and measurements in order to establish a viable mirror technology which combines high reflectivity with simplicity and low cost. The following technologies were evaluated: Aluminized Mylar film glued to the fibre ends, 3M Enhanced Specular Reflectance film glued to the fibre ends, Thin Film Aluminium vacuum coated on the fibre ends. The tests show that Aluminized Mylar film is a viable solution fulfilling all SciFi requirements. ESR film leads potentially to a higher reflectivity but its usability when glued to fibre ends could not (yet) be demonstrated. The Thin Film Aluminium coating disqualifies for reasons of cost and complexity without any performance gain. This report is meant as backup document for the LHCb SciFi TDR document to be submitted in February 2014.

Scenarios of giant planet formation and evolution and their impact on the formation of habitable terrestrial planets.

Science.gov (United States)

Morbidelli, Alessandro

2014-04-28

In our Solar System, there is a clear divide between the terrestrial and giant planets. These two categories of planets formed and evolved separately, almost in isolation from each other. This was possible because Jupiter avoided migrating into the inner Solar System, most probably due to the presence of Saturn, and never acquired a large-eccentricity orbit, even during the phase of orbital instability that the giant planets most likely experienced. Thus, the Earth formed on a time scale of several tens of millions of years, by collision of Moon- to Mars-mass planetary embryos, in a gas-free and volatile-depleted environment. We do not expect, however, that this clear cleavage between the giant and terrestrial planets is generic. In many extrasolar planetary systems discovered to date, the giant planets migrated into the vicinity of the parent star and/or acquired eccentric orbits. In this way, the evolution and destiny of the giant and terrestrial planets become intimately linked. This paper discusses several evolutionary patterns for the giant planets, with an emphasis on the consequences for the formation and survival of habitable terrestrial planets. The conclusion is that we should not expect Earth-like planets to be typical in terms of physical and orbital properties and accretion history. Most habitable worlds are probably different, exotic worlds.

Contributions of Small-Scale Community-Owned Infrastructure (SCI ...

African Journals Online (AJOL)

Contributions of Small-Scale Community-Owned Infrastructure (SCI) and Asset ... Descriptive analysis was employed to explain access to productive rural ... for asset maintenance and replacement; support targeted value chains given the ...

Emotional Intelligence in Patients with Spinal Cord Injury (SCI).

Science.gov (United States)

Saberi, Hooshang; Ghajarzadeh, Mahsa

2017-05-01

Spinal Cord Injury (SCI) is a devastating situation. Spinal Cord Injury affects functional, psychological and socioeconomic aspects of patients' lives. The ability to accomplish and explicate the one's own and other's feelings and emotions to spread over appropriate information for confirming thoughts and actions is defined as emotional intelligence (EI). The goal of this study was to evaluate depression and EI in SCI patients in comparison with healthy subjects. One-hundred-ten patients with SCI and 80 healthy subjects between Aug 2014 and Aug 2015 were enrolled. The study was conducted in Imam Hospital, Tehran, Iran. All participants were asked to fill valid and reliable Persian version Emotional Quotient inventory (EQ-i) and Beck Depression Inventory (BDI). All data were analyzed using SPSS. Data were presented as Mean±SD for continuous or frequencies for categorical variables. Continuous variables compared by means of independent sample t -test. P -values less than 0.05 were considered as significant. Mean age of patients was 28.7 and mean age of controls was 30.2 yr. Spinal cord injury in 20 (18.3%) were at cervical level, in 83 (75.4%) were thoracic and in 7 (6.3%) were lumbar. Mean values of independence, stress tolerance, self-actualization, emotional Self-Awareness, reality testing, Impulse Control, flexibility, responsibility, and assertiveness were significantly different between cases and controls. Mean values of stress tolerance, optimism, self-regard, and responsibility were significantly different between three groups with different injury level. Most scales were not significantly different between male and female cases. Emotional intelligence should be considered in SCI cases as their physical and psychological health is affected by their illness.

Spinal Cord Injury Clinical Registries: Improving Care across the SCI Care Continuum by Identifying Knowledge Gaps.

Science.gov (United States)

Dvorak, Marcel F; Cheng, Christiana L; Fallah, Nader; Santos, Argelio; Atkins, Derek; Humphreys, Suzanne; Rivers, Carly S; White, Barry A B; Ho, Chester; Ahn, Henry; Kwon, Brian K; Christie, Sean; Noonan, Vanessa K

2017-10-15

Timely access and ongoing delivery of care and therapeutic interventions is needed to maximize recovery and function after traumatic spinal cord injury (tSCI). To ensure these decisions are evidence-based, access to consistent, reliable, and valid sources of clinical data is required. The Access to Care and Timing Model used data from the Rick Hansen SCI Registry (RHSCIR) to generate a simulation of healthcare delivery for persons after tSCI and to test scenarios aimed at improving outcomes and reducing the economic burden of SCI. Through model development, we identified knowledge gaps and challenges in the literature and current health outcomes data collection throughout the continuum of SCI care. The objectives of this article were to describe these gaps and to provide recommendations for bridging them. Accurate information on injury severity after tSCI was hindered by difficulties in conducting neurological assessments and classifications of SCI (e.g., timing), variations in reporting, and the lack of a validated SCI-specific measure of associated injuries. There was also limited availability of reliable data on patient factors such as multi-morbidity and patient-reported measures. Knowledge gaps related to structures (e.g., protocols) and processes (e.g., costs) at each phase of care have prevented comprehensive evaluation of system performance. Addressing these knowledge gaps will enhance comparative and cost-effectiveness evaluations to inform decision-making and standards of care. Recommendations to do so were: standardize data element collection and facilitate database linkages, validate and adopt more outcome measures for SCI, and increase opportunities for collaborations with stakeholders from diverse backgrounds.

Planet Hunters: Kepler by Eye

Science.gov (United States)

Schwamb, Megan E.; Lintott, C.; Fischer, D.; Smith, A. M.; Boyajian, T. S.; Brewer, J. M.; Giguere, M. J.; Lynn, S.; Parrish, M.; Schawinski, K.; Schmitt, J.; Simpson, R.; Wang, J.

2014-01-01

Planet Hunters (http://www.planethunters.org), part of the Zooniverse's (http://www.zooniverse.org) collection of online citizen science projects, uses the World Wide Web to enlist the general public to identify transits in the pubic Kepler light curves. Planet Hunters utilizes human pattern recognition to identify planet transits that may be missed by automated detection algorithms looking for periodic events. Referred to as ‘crowdsourcing’ or ‘citizen science’, the combined assessment of many non-expert human classifiers with minimal training can often equal or best that of a trained expert and in many cases outperform the best machine-learning algorithm. Visitors to the Planet Hunters' website are presented with a randomly selected ~30-day light curve segment from one of Kepler’s ~160,000 target stars and are asked to draw boxes to mark the locations of visible transits in the web interface. 5-10 classifiers review each 30-day light curve segment. Since December 2010, more than 260,000 volunteers world wide have participated, contributing over 20 million classifications. We have demonstrated the success of a citizen science approach with the project’s more than 20 planet candidates, the discovery of PH1b, a transiting circumbinary planet in a quadruple star system, and the discovery of PH2-b, a confirmed Jupiter-sized planet in the habitable zone of a Sun-like star. I will provide an overview of Planet Hunters, highlighting several of project's most recent exoplanet and astrophysical discoveries. Acknowledgements: MES was supported in part by a NSF AAPF under award AST-1003258 and a American Philosophical Society Franklin Grant. We acknowledge support from NASA ADAP12-0172 grant to PI Fischer.

Treatment of Neuropathic Pain after SCI with a Catalytic Oxidoreductant

Science.gov (United States)

2015-10-01

application. Briefly for induction of SCI in the rat, male Sprague-Dawley rats (250-275g) were anesthetized with inhaled isoflurane and body temperature was...cord have been extracted, fixed, and subsequently cryo - sectioned. Task 8: At 24, 48 hours, or 7 days post-SCI, exsanguinate a subset of the...model this MnP affords whole brain radioprotection [10, 11]. MnTnBuOE-2-PyP5+ [10]10] and MnTnHex-2-PyP5+ [3] acted as radio- and chemo-sensitizors in

Seeding life on the moons of the outer planets via lithopanspermia.

Science.gov (United States)

Worth, R J; Sigurdsson, Steinn; House, Christopher H

2013-12-01

Material from the surface of a planet can be ejected into space by a large impact and could carry primitive life-forms with it. We performed n-body simulations of such ejecta to determine where in the Solar System rock from Earth and Mars may end up. We found that, in addition to frequent transfer of material among the terrestrial planets, transfer of material from Earth and Mars to the moons of Jupiter and Saturn is also possible, but rare. We expect that such transfers were most likely to occur during the Late Heavy Bombardment or during the ensuing 1-2 billion years. At this time, the icy moons were warmer and likely had little or no ice shell to prevent meteorites from reaching their liquid interiors. We also note significant rates of re-impact in the first million years after ejection. This could re-seed life on a planet after partial or complete sterilization by a large impact, which would aid the survival of early life during the Late Heavy Bombardment.

WHY ARE PULSAR PLANETS RARE?

Energy Technology Data Exchange (ETDEWEB)

Martin, Rebecca G.; Livio, Mario; Palaniswamy, Divya [Department of Physics and Astronomy, University of Nevada, Las Vegas, 4505 South Maryland Parkway, Las Vegas, NV 89154 (United States)

2016-12-01

Pulsar timing observations have revealed planets around only a few pulsars. We suggest that the rarity of these planets is due mainly to two effects. First, we show that the most likely formation mechanism requires the destruction of a companion star. Only pulsars with a suitable companion (with an extreme mass ratio) are able to form planets. Second, while a dead zone (a region of low turbulence) in the disk is generally thought to be essential for planet formation, it is most probably rare in disks around pulsars, because of the irradiation from the pulsar. The irradiation strongly heats the inner parts of the disk, thus pushing the inner boundary of the dead zone out. We suggest that the rarity of pulsar planets can be explained by the low probability for these two requirements to be satisfied: a very low-mass companion and a dead zone.

Extreme orbital evolution from hierarchical secular coupling of two giant planets

International Nuclear Information System (INIS)

Teyssandier, Jean; Naoz, Smadar; Lizarraga, Ian; Rasio, Frederic A.

2013-01-01

Observations of exoplanets over the last two decades have revealed a new class of Jupiter-size planets with orbital periods of a few days, the so-called 'hot Jupiters'. Recent measurements using the Rossiter-McLaughlin effect have shown that many (∼50%) of these planets are misaligned; furthermore, some (∼15%) are even retrograde with respect to the stellar spin axis. Motivated by these observations, we explore the possibility of forming retrograde orbits in hierarchical triple configurations consisting of a star-planet inner pair with another giant planet, or brown dwarf, in a much wider orbit. Recently, it was shown that in such a system, the inner planet's orbit can flip back and forth from prograde to retrograde and can also reach extremely high eccentricities. Here we map a significant part of the parameter space of dynamical outcomes for these systems. We derive strong constraints on the orbital configurations for the outer perturber (the tertiary) that could lead to the formation of hot Jupiters with misaligned or retrograde orbits. We focus only on the secular evolution, neglecting other dynamical effects such as mean-motion resonances, as well as all dissipative forces. For example, with an inner Jupiter-like planet initially on a nearly circular orbit at 5 AU, we show that a misaligned hot Jupiter is likely to be formed in the presence of a more massive planetary companion (>2 M J ) within ∼140 AU of the inner system, with mutual inclination >50° and eccentricity above ∼0.25. This is in striking contrast to the test particle approximation, where an almost perpendicular configuration can still cause large-eccentricity excitations, but flips of an inner Jupiter-like planet are much less likely to occur. The constraints we derive can be used to guide future observations and, in particular, searches for more distant companions in systems containing a hot Jupiter.

Infrared radiation from an extrasolar planet.

Science.gov (United States)

Deming, Drake; Seager, Sara; Richardson, L Jeremy; Harrington, Joseph

2005-04-07

A class of extrasolar giant planets--the so-called 'hot Jupiters' (ref. 1)--orbit within 0.05 au of their primary stars (1 au is the Sun-Earth distance). These planets should be hot and so emit detectable infrared radiation. The planet HD 209458b (refs 3, 4) is an ideal candidate for the detection and characterization of this infrared light because it is eclipsed by the star. This planet has an anomalously large radius (1.35 times that of Jupiter), which may be the result of ongoing tidal dissipation, but this explanation requires a non-zero orbital eccentricity (approximately 0.03; refs 6, 7), maintained by interaction with a hypothetical second planet. Here we report detection of infrared (24 microm) radiation from HD 209458b, by observing the decrement in flux during secondary eclipse, when the planet passes behind the star. The planet's 24-microm flux is 55 +/- 10 microJy (1sigma), with a brightness temperature of 1,130 +/- 150 K, confirming the predicted heating by stellar irradiation. The secondary eclipse occurs at the midpoint between transits of the planet in front of the star (to within +/- 7 min, 1sigma), which means that a dynamically significant orbital eccentricity is unlikely.

Starting a Planet Protectors Club

Science.gov (United States)

US Environmental Protection Agency, 2007

2007-01-01

If your mission is to teach children how to reduce, reuse, and recycle waste and create the next generation of Planet Protectors, perhaps leading a Planet Protectors Club is part of your future challenges. You don't have to be an expert in waste reduction and recycling to lead a a Planet Protectors Club. You don't even have to be a teacher. You do…

MIGRATION THEN ASSEMBLY: FORMATION OF NEPTUNE-MASS PLANETS INSIDE 1 AU

International Nuclear Information System (INIS)

Hansen, Brad M. S.; Murray, Norm

2012-01-01

We demonstrate that the observed distribution of 'hot Neptune'/'super-Earth' systems is well reproduced by a model in which planet assembly occurs in situ, with no significant migration post-assembly. This is achieved only if the amount of mass in rocky material is ∼50-100 M ⊕ interior to 1 AU. Such a reservoir of material implies that significant radial migration of solid material takes place, and that it occurs before the stage of final planet assembly. The model not only reproduces the general distribution of mass versus period but also the detailed statistics of multiple planet systems in the sample. We furthermore demonstrate that cores of this size are also likely to meet the criterion to gravitationally capture gas from the nebula, although accretion is rapidly limited by the opening of gaps in the gas disk. If the mass growth is limited by this tidal truncation, then the scenario sketched here naturally produces Neptune-mass objects with substantial components of both rock and gas, as is observed. The quantitative expectations of this scenario are that most planets in the 'hot Neptune/super-Earth' class inhabit multiple-planet systems, with characteristic orbital spacings. The model also provides a natural division into gas-rich (hot Neptune) and gas-poor (super-Earth) classes at fixed period. The dividing mass ranges from ∼3 M ⊕ at 10 day orbital periods to ∼10 M ⊕ at 100 day orbital periods. For orbital periods <10 days, the division is less clear because a gas atmosphere may be significantly eroded by stellar radiation.

Extrasolar Planets Observed with JWST and the ELTs

Science.gov (United States)

Deming, L. Drake

2010-01-01

The advent of cryogenic space-borne infrared observatories such as the Spitzer Space Telescope has lead to a revolution in the study of planets and planetary systems orbiting sun-like stars. Already Spitzer has characterized the emergent infrared spectra of close-in giant exoplanets using transit and eclipse techniques. The James Webb Space Telescope (JWST) will be able to extend these studies to superEarth exoplanets orbiting in the habitable zones of M-dwarf stars in the near solar neighborhood. The forthcoming ground-based Extremely Large Telescopes (ELTs) will playa key role in these studies, being especially valuable for spectroscopy at higher spectral resolving powers where large photon fluxes are needed. The culmination of this work within the next two decades will be the detection and spectral characterization of the major molecular constituents in the atmosphere of a habitable superEarth orbiting a nearby lower main sequence star.

Pressure Relief Behaviors and Weight-Shifting Activities to Prevent Pressure Ulcers in Persons with SCI

Science.gov (United States)

2014-10-01

SUPPLEMENTARY NOTES 14. ABSTRACT Pressure ulcers (PU) are the most costly secondary complication following an SCI. In addition to the medical costs ...Introduction Pressure ulcers (PU) are the most costly secondary complication following an SCI. In addition to the medical costs , the development of a...Prevent Pressure Ulcers in Persons with SCI PRINCIPAL INVESTIGATOR: Stephen Sprigle, PhD CONTRACTING ORGANIZATION: Georgia Tech Research

Kepler's first rocky planet

DEFF Research Database (Denmark)

Batalha, N.M.; Borucki, W.J.; Bryson, S.T.

2011-01-01

NASA's Kepler Mission uses transit photometry to determine the frequency of Earth-size planets in or near the habitable zone of Sun-like stars. The mission reached a milestone toward meeting that goal: the discovery of its first rocky planet, Kepler-10b. Two distinct sets of transit events were...... tests on the photometric and pixel flux time series established the viability of the planet candidates triggering ground-based follow-up observations. Forty precision Doppler measurements were used to confirm that the short-period transit event is due to a planetary companion. The parent star is bright...

People Interview: Using sci-fi to promote physics

Science.gov (United States)

2009-07-01

INTERVIEW Using sci-fi to promote physics Robert Flack, a research fellow at University College London, talks to David Smith about science writing and the consequences for physicists of books like Angels and Demons.

Taking Extreme Space Weather to the Milky Way

Science.gov (United States)

Pesnell, W. Dean

2014-06-01

Extreme Space Weather events are large solar flares or geomagnetic storms, which can cause economic damage that cost billions of dollars to recover from. We have few examples of such events; only the Carrington Event (the solar superstorm) has superlatives in three categories: size of solar flare, drop in Dst, and amplitude of aa. Kepler observations show that stars similar to the Sun can have flares releasing thousands of times more energy than an X-class flare. These flares would strongly affect the atmosphere surrounding a planet orbiting such a star. Particle and magnetic field outflows from these stars could also be present. We are investigating the level of solar activity that is necessary to strongly affect the atmosphere of terrestrial planets. We assume that a habitable planet requires an atmosphere with a temperature and composition that is stable in time. Can we then extrapolate results from our solar system to determine a space of stellar parameters in which habitable planets can exist?

Constraint on Additional Planets in Planetary Systems Discovered Through the Channel of High-magnification Gravitational Microlensing Events

Science.gov (United States)

Shin, I.-G.; Han, C.; Choi, J.-Y.; Hwang, K.-H.; Jung, Y.-K.; Park, H.

2015-04-01

High-magnification gravitational microlensing events provide an important channel of detecting planetary systems with multiple giants located at their birth places. In order to investigate the potential existence of additional planets, we reanalyze the light curves of the eight high-magnification microlensing events, for each of which a single planet was previously detected. The analyzed events include OGLE-2005-BLG-071, OGLE-2005-BLG-169, MOA-2007-BLG-400, MOA-2008-BLG-310, MOA-2009-BLG-319, MOA-2009-BLG-387, MOA-2010-BLG-477, and MOA-2011-BLG-293. We find that including an additional planet improves fits with {Δ }{{χ }2}\\lt 80 for seven out of eight analyzed events. For MOA-2009-BLG-319, the improvement is relatively big with {Δ }{{χ }2}∼ 143. From inspection of the fits, we find that the improvement of the fits is attributed to systematics in data. Although no clear evidence of additional planets is found, it is still possible to constrain the existence of additional planets in the parameter space. For this purpose, we construct exclusion diagrams showing the confidence levels excluding the existence of an additional planet as a function of its separation and mass ratio. We also present the exclusion ranges of additional planets with 90% confidence level for Jupiter-, Saturn-, and Uranus-mass planets.

Scalable Earth-observation Analytics for Geoscientists: Spacetime Extensions to the Array Database SciDB

Science.gov (United States)

Appel, Marius; Lahn, Florian; Pebesma, Edzer; Buytaert, Wouter; Moulds, Simon

2016-04-01

Today's amount of freely available data requires scientists to spend large parts of their work on data management. This is especially true in environmental sciences when working with large remote sensing datasets, such as obtained from earth-observation satellites like the Sentinel fleet. Many frameworks like SpatialHadoop or Apache Spark address the scalability but target programmers rather than data analysts, and are not dedicated to imagery or array data. In this work, we use the open-source data management and analytics system SciDB to bring large earth-observation datasets closer to analysts. Its underlying data representation as multidimensional arrays fits naturally to earth-observation datasets, distributes storage and computational load over multiple instances by multidimensional chunking, and also enables efficient time-series based analyses, which is usually difficult using file- or tile-based approaches. Existing interfaces to R and Python furthermore allow for scalable analytics with relatively little learning effort. However, interfacing SciDB and file-based earth-observation datasets that come as tiled temporal snapshots requires a lot of manual bookkeeping during ingestion, and SciDB natively only supports loading data from CSV-like and custom binary formatted files, which currently limits its practical use in earth-observation analytics. To make it easier to work with large multi-temporal datasets in SciDB, we developed software tools that enrich SciDB with earth observation metadata and allow working with commonly used file formats: (i) the SciDB extension library scidb4geo simplifies working with spatiotemporal arrays by adding relevant metadata to the database and (ii) the Geospatial Data Abstraction Library (GDAL) driver implementation scidb4gdal allows to ingest and export remote sensing imagery from and to a large number of file formats. Using added metadata on temporal resolution and coverage, the GDAL driver supports time-based ingestion of

Evidence of an Upper Bound on the Masses of Planets and Its Implications for Giant Planet Formation

Science.gov (United States)

Schlaufman, Kevin C.

2018-01-01

Celestial bodies with a mass of M≈ 10 {M}{Jup} have been found orbiting nearby stars. It is unknown whether these objects formed like gas-giant planets through core accretion or like stars through gravitational instability. I show that objects with M≲ 4 {M}{Jup} orbit metal-rich solar-type dwarf stars, a property associated with core accretion. Objects with M≳ 10 {M}{Jup} do not share this property. This transition is coincident with a minimum in the occurrence rate of such objects, suggesting that the maximum mass of a celestial body formed through core accretion like a planet is less than 10 {M}{Jup}. Consequently, objects with M≳ 10 {M}{Jup} orbiting solar-type dwarf stars likely formed through gravitational instability and should not be thought of as planets. Theoretical models of giant planet formation in scaled minimum-mass solar nebula Shakura–Sunyaev disks with standard parameters tuned to produce giant planets predict a maximum mass nearly an order of magnitude larger. To prevent newly formed giant planets from growing larger than 10 {M}{Jup}, protoplanetary disks must therefore be significantly less viscous or of lower mass than typically assumed during the runaway gas accretion stage of giant planet formation. Either effect would act to slow the Type I/II migration of planetary embryos/giant planets and promote their survival. These inferences are insensitive to the host star mass, planet formation location, or characteristic disk dissipation time.

The Cassini-Huygens visit to Saturn an historic mission to the ringed planet

CERN Document Server

Meltzer, Michael

2015-01-01

Cassini-Huygens was the most ambitious and successful space journey ever launched to the outer Solar System. This book examines all aspects of the journey: its conception and planning; the lengthy political processes needed to make it a reality; the engineering and development required to build the spacecraft; its 2.2-billion mile journey from Earth to the Ringed Planet; and the amazing discoveries from the mission. The author traces how the visions of a few brilliant scientists matured, gained popularity, and eventually became a reality. Innovative technical leaps were necessary to assemble such a multifaceted spacecraft and reliably operate it while it orbited a planet so far from our own. The Cassini-Huygens spacecraft design evolved from other deep space efforts, most notably the Galileo mission to Jupiter, enabling the voluminous, paradigm-shifting scientific data collected by the spacecraft.  Some of these discoveries are absolute gems. A small satellite that scientists once thought of as a dead pi...

Exploring the planets a memoir

CERN Document Server

Taylor, Fred

2016-01-01

This book is an informal, semi-autobiographical history, from the particular viewpoint of someone who was involved, of the exploration of the Solar System using spacecraft. The author is a Northumbrian, a Liverpudlian, a Californian, and an Oxford Don with half a century of experience of devising and deploying experiments to study the Earth and the planets, moons, and small bodies of the Solar System. Along with memories and anecdotes about his experiences as a participant in the space programme from its earliest days to the present, he describes in non-technical terms the science goals that drove the projects as well as the politics, pressures, and problems that had to be addressed and overcome on the way. The theme is the scientific intent of these ambitious voyages of discovery, and the joys and hardships of working to see them achieved. The narrative gives a first-hand account of things like how Earth satellites came to revolutionize weather forecasting, starting in the 1960s; how observations from space ...

Magnetospheric Truncation, Tidal Inspiral, and the Creation of Short-period and Ultra-short-period Planets

Energy Technology Data Exchange (ETDEWEB)

Lee, Eve J.; Chiang, Eugene, E-mail: evelee@berkeley.edu [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States)

2017-06-10

Sub-Neptunes around FGKM dwarfs are evenly distributed in log orbital period down to ∼10 days, but dwindle in number at shorter periods. Both the break at ∼10 days and the slope of the occurrence rate down to ∼1 day can be attributed to the truncation of protoplanetary disks by their host star magnetospheres at corotation. We demonstrate this by deriving planet occurrence rate profiles from empirical distributions of pre-main-sequence stellar rotation periods. Observed profiles are better reproduced when planets are distributed randomly in disks—as might be expected if planets formed in situ—rather than piled up near disk edges, as would be the case if they migrated in by disk torques. Planets can be brought from disk edges to ultra-short (<1 day) periods by asynchronous equilibrium tides raised on their stars. Tidal migration can account for how ultra-short-period planets are more widely spaced than their longer-period counterparts. Our picture provides a starting point for understanding why the sub-Neptune population drops at ∼10 days regardless of whether the host star is of type FGK or early M. We predict planet occurrence rates around A stars to also break at short periods, but at ∼1 day instead of ∼10 days because A stars rotate faster than stars with lower masses (this prediction presumes that the planetesimal building blocks of planets can drift inside the dust sublimation radius).

Magnetospheric Truncation, Tidal Inspiral, and the Creation of Short-period and Ultra-short-period Planets

International Nuclear Information System (INIS)

Lee, Eve J.; Chiang, Eugene

2017-01-01

Sub-Neptunes around FGKM dwarfs are evenly distributed in log orbital period down to ∼10 days, but dwindle in number at shorter periods. Both the break at ∼10 days and the slope of the occurrence rate down to ∼1 day can be attributed to the truncation of protoplanetary disks by their host star magnetospheres at corotation. We demonstrate this by deriving planet occurrence rate profiles from empirical distributions of pre-main-sequence stellar rotation periods. Observed profiles are better reproduced when planets are distributed randomly in disks—as might be expected if planets formed in situ—rather than piled up near disk edges, as would be the case if they migrated in by disk torques. Planets can be brought from disk edges to ultra-short (<1 day) periods by asynchronous equilibrium tides raised on their stars. Tidal migration can account for how ultra-short-period planets are more widely spaced than their longer-period counterparts. Our picture provides a starting point for understanding why the sub-Neptune population drops at ∼10 days regardless of whether the host star is of type FGK or early M. We predict planet occurrence rates around A stars to also break at short periods, but at ∼1 day instead of ∼10 days because A stars rotate faster than stars with lower masses (this prediction presumes that the planetesimal building blocks of planets can drift inside the dust sublimation radius).

Giant Planet Candidates, Brown Dwarfs, and Binaries from the SDSS-III MARVELS Planet Survey.

Science.gov (United States)

Thomas, Neil; Ge, Jian; Li, Rui; de Lee, Nathan M.; Heslar, Michael; Ma, Bo; SDSS-Iii Marvels Team

2015-01-01

We report the discoveries of giant planet candidates, brown dwarfs, and binaries from the SDSS-III MARVELS survey. The finalized 1D pipeline has provided 18 giant planet candidates, 16 brown dwarfs, and over 500 binaries. An additional 96 targets having RV variability indicative of a giant planet companion are also reported for future investigation. These candidates are found using the advanced MARVELS 1D data pipeline developed at UF from scratch over the past three years. This pipeline carefully corrects most of the instrument effects (such as trace, slant, distortion, drifts and dispersion) and observation condition effects (such as illumination profile, fiber degradation, and tracking variations). The result is long-term RV precisions that approach the photon limits in many cases for the ~89,000 individual stellar observations. A 2D version of the pipeline that uses interferometric information is nearing completion and is demonstrating a reduction of errors to half the current levels. The 2D processing will be used to increase the robustness of the detections presented here and to find new candidates in RV regions not confidently detectable with the 1D pipeline. The MARVELS survey has produced the largest homogeneous RV measurements of 3300 V=7.6-12 FGK stars with a well defined cadence of 27 RV measurements over 2 years. The MARVELS RV data and other follow-up data (photometry, high contrast imaging, high resolution spectroscopy and RV measurements) will explore the diversity of giant planet companion formation and evolution around stars with a broad range in metallicity (Fe/H -1.5-0.5), mass ( 0.6-2.5M(sun)), and environment (thin disk and thick disk), and will help to address the key scientific questions identified for the MARVELS survey including, but not limited to: Do metal poor stars obey the same trends for planet occurrence as metal rich stars? What is the distribution of giant planets around intermediate-mass stars and binaries? Is the 'planet desert

Compact, Passively Q-Switched Nd:YAG Laser for the MESSENGER Mission to the Planet Mercury

Science.gov (United States)

Krebs, Danny J.; Novo-Gradac, Anne-Marie; Li, Steven X.; Lindauer, Steven J.; Afzal, Robert S.; Yu, Antony

2004-01-01

A compact, passively Q-switched Nd:YAG laser has been developed for the Mercury Laser Altimeter (MLA) instrument which is an instrument on the MESSENGER mission to the planet Mercury. The laser achieves 5.4 percent efficiency with a near diffraction limited beam. It has passed all space flight environmental tests at system, instrument, and satellite integration. The laser design draws on a heritage of previous laser altimetry missions, specifically ISESAT and Mars Global Surveyor; but incorporates thermal management features unique to the requirements of an orbit of the planet Mercury.

CONDITIONS OF PASSAGE AND ENTRAPMENT OF TERRESTRIAL PLANETS IN SPIN-ORBIT RESONANCES

International Nuclear Information System (INIS)

Makarov, Valeri V.

2012-01-01

The dynamical evolution of terrestrial planets resembling Mercury in the vicinity of spin-orbit resonances is investigated using comprehensive harmonic expansions of the tidal torque taking into account the frequency-dependent quality factors and Love numbers. The torque equations are integrated numerically with a small step in time, including the oscillating triaxial torque components but neglecting the layered structure of the planet and assuming a zero obliquity. We find that a Mercury-like planet with a current value of orbital eccentricity (0.2056) is always captured in 3:2 resonance. The probability of capture in the higher 2:1 resonance is approximately 0.23. These results are confirmed by a semi-analytical estimation of capture probabilities as functions of eccentricity for both prograde and retrograde evolutions of spin rate. As follows from analysis of equilibrium torques, entrapment in 3:2 resonance is inevitable at eccentricities between 0.2 and 0.41. Considering the phase space parameters at the times of periastron, the range of spin rates and phase angles for which an immediate resonance passage is triggered is very narrow, and yet a planet like Mercury rarely fails to align itself into this state of unstable equilibrium before it traverses 2:1 resonance.

ARCHITECTURE AND DYNAMICS OF KEPLER'S CANDIDATE MULTIPLE TRANSITING PLANET SYSTEMS

Energy Technology Data Exchange (ETDEWEB)

Lissauer, Jack J.; Jenkins, Jon M.; Borucki, William J.; Bryson, Stephen T.; Howell, Steve B. [NASA Ames Research Center, Moffett Field, CA 94035 (United States); Ragozzine, Darin; Holman, Matthew J.; Carter, Joshua A. [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States); Fabrycky, Daniel C.; Fortney, Jonathan J. [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States); Steffen, Jason H. [Fermilab Center for Particle Astrophysics, Batavia, IL 60510 (United States); Ford, Eric B. [211 Bryant Space Science Center, University of Florida, Gainesville, FL 32611 (United States); Shporer, Avi [Las Cumbres Observatory Global Telescope Network, Santa Barbara, CA 93117 (United States); Rowe, Jason F.; Quintana, Elisa V.; Caldwell, Douglas A. [SETI Institute/NASA Ames Research Center, Moffett Field, CA 94035 (United States); Batalha, Natalie M. [Department of Physics and Astronomy, San Jose State University, San Jose, CA 95192 (United States); Ciardi, David [Exoplanet Science Institute/Caltech, Pasadena, CA 91125 (United States); Dunham, Edward W. [Lowell Observatory, Flagstaff, AZ 86001 (United States); Gautier, Thomas N. III, E-mail: Jack.Lissauer@nasa.gov [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States); and others

2011-11-01

About one-third of the {approx}1200 transiting planet candidates detected in the first four months of Kepler data are members of multiple candidate systems. There are 115 target stars with two candidate transiting planets, 45 with three, 8 with four, and 1 each with five and six. We characterize the dynamical properties of these candidate multi-planet systems. The distribution of observed period ratios shows that the vast majority of candidate pairs are neither in nor near low-order mean-motion resonances. Nonetheless, there are small but statistically significant excesses of candidate pairs both in resonance and spaced slightly too far apart to be in resonance, particularly near the 2:1 resonance. We find that virtually all candidate systems are stable, as tested by numerical integrations that assume a nominal mass-radius relationship. Several considerations strongly suggest that the vast majority of these multi-candidate systems are true planetary systems. Using the observed multiplicity frequencies, we find that a single population of planetary systems that matches the higher multiplicities underpredicts the number of singly transiting systems. We provide constraints on the true multiplicity and mutual inclination distribution of the multi-candidate systems, revealing a population of systems with multiple super-Earth-size and Neptune-size planets with low to moderate mutual inclinations.

A 3π Search for Planet Nine at 3.4 μm with WISE and NEOWISE

Science.gov (United States)

Meisner, A. M.; Bromley, B. C.; Kenyon, S. J.; Anderson, T. E.

2018-04-01

The recent “Planet Nine” hypothesis has led to many observational and archival searches for this giant planet proposed to orbit the Sun at hundreds of astronomical units. While trans-Neptunian object searches are typically conducted in the optical, models suggest Planet Nine could be self-luminous and potentially bright enough at ∼3–5 μm to be detected by the Wide-field Infrared Survey Explorer (WISE). We have previously demonstrated a Planet Nine search methodology based on time-resolved WISE coadds, allowing us to detect moving objects much fainter than would be possible using single-frame extractions. In the present work, we extend our 3.4 μm (W1) search to cover more than three-quarters of the sky and incorporate four years of WISE observations spanning a seven-year time period. This represents the deepest and widest-area WISE search for Planet Nine to date. We characterize the spatial variation of our survey’s sensitivity and rule out the presence of Planet Nine in the parameter space searched at W1 < 16.7 in high Galactic latitude regions (90% completeness).

Red Optical Planet Survey: A radial velocity search for low mass M dwarf planets

Directory of Open Access Journals (Sweden)

Minniti D.

2013-04-01

Full Text Available We present radial velocity results from our Red Optical Planet Survey (ROPS, aimed at detecting low-mass planets orbiting mid-late M dwarfs. The ∼10 ms−1 precision achieved over 2 consecutive nights with the MIKE spectrograph at Magellan Clay is also found on week long timescales with UVES at VLT. Since we find that UVES is expected to attain photon limited precision of order 2 ms−1 using our novel deconvolution technique, we are limited only by the (≤10 ms−1 stability of atmospheric lines. Rocky planet frequencies of η⊕ = 0.3−0.7 lead us to expect high planet yields, enabling determination of η⊕ for the uncharted mid-late M dwarfs with modest surveys.

News

Science.gov (United States)

2002-11-01

Resources: First Faulkes Telescope on its way! Events: Everything under the Sun - GIREP 2002 Experiments: The most beautiful experiment, your favourite demonstration Science year: Planet Science takes off Resources: New CD packages Lecture: Fantastic Plastic Summer workshop: The Wright Stuff Resources: Amazing Space 14-16 curriculum: 21st century science ASE conference: ASE 2003 South Africa: Sasol SciFest Earth sciences: JESEI: the answer to all your Earthly problems

Effect of and satisfaction with www.elearnSCI.org for training of nurse students

DEFF Research Database (Denmark)

Liu, N; Li, X W; Zhou, M W

2014-01-01

STUDY DESIGN: Interventional training session. OBJECTIVE: To investigate the effect and satisfaction with didactic training using printed text of a submodule of www.elearnSCI.org for nurse students and to assess the answers of each question. SETTING: A Peking University teaching hospital. METHODS......: Twenty-eight nurse students in two groups (14 in each) were involved. Only group A received a translated print-out of the slides from the 'Nursing management' submodule in www.elearnSCI.org for 1-h self-study before the class. At the beginning of class, both groups were tested using the self assessment...... presentation are effective methods for training the content of www.elearnSCI.org to nurse students. The training satisfaction of this submodule within the www.elearnSCI.org is favorable....

Atmospheric dynamics of tidally synchronized extrasolar planets.

Science.gov (United States)

Cho, James Y-K

2008-12-13

Tidally synchronized planets present a new opportunity for enriching our understanding of atmospheric dynamics on planets. Subject to an unusual forcing arrangement (steady irradiation on the same side of the planet throughout its orbit), the dynamics on these planets may be unlike that on any of the Solar System planets. Characterizing the flow pattern and temperature distribution on the extrasolar planets is necessary for reliable interpretation of data currently being collected, as well as for guiding future observations. In this paper, several fundamental concepts from atmospheric dynamics, likely to be central for characterization, are discussed. Theoretical issues that need to be addressed in the near future are also highlighted.

Value of Hipparcos Catalogue shown by planet assessments

Science.gov (United States)

1996-08-01

, or deuterium. Even the "worst-case" mass quoted here for the companion of 47 Ursae Majoris, 22 Jupiter masses, is only a maximum, not a measurement. So the companion is almost certainly a true planet with less than 17 times the mass of Jupiter. For the star 70 Virginis, the distance newly established by Hipparcos is 59 light-years. Even on the least favourable assumptions about its orbit, the companion cannot have more than 65 Jupiter masses. It could be brown dwarf rather than a planet, but not a true star. Much more ambiguous is the result for 51 Pegasi. Its distance is 50 light-years and theoretically the companion could have more than 500 Jupiter masses, or half the mass of the Sun. This is a peculiar case anyway, because the companion is very close to 51 Pegasi. Small planets of the size of the Earth might be more promising as abodes of life than the large planets detectable by present astronomical methods. Space scientists are now reviewing methods of detecting the presence of life on alien planets by detecting the infrared signature of ozone in a planet's atmosphere. Ozone is a by-product of oxygen gas, which in turn is supposed to be generated only by life similar to that on the Earth. Meanwhile the detection of planets of whatever size is a tour de force for astronomers, and by analogy with the Solar System one may suppose that large planets are often likely to be accompanied by smaller ones. "Hipparcos was not conceived to look for planets," comments Michael Perryman, ESA's project scientist for Hipparcos, "and this example of assistance to our fellow-astronomers involves a very small sample of our measurements. But it is a timely result when we are considering planet-hunting missions for the 21st Century. The possibilities include a super-Hipparcos that could detect directly the wobbles in nearby stars due to the presence of planets." Hipparcos Catalogue ready for use The result from Hipparcos on alien planets coincides with the completion of the Hipparcos

Probing Clouds in Planets with a Simple Radiative Transfer Model: The Jupiter Case

Science.gov (United States)

Mendikoa, Inigo; Perez-Hoyos, Santiago; Sanchez-Lavega, Agustin

2012-01-01

Remote sensing of planets evokes using expensive on-orbit satellites and gathering complex data from space. However, the basic properties of clouds in planetary atmospheres can be successfully estimated with small telescopes even from an urban environment using currently available and affordable technology. This makes the process accessible for…

Materials and design concepts for space-resilient structures

Science.gov (United States)

Naser, Mohannad Z.; Chehab, Alaa I.

2018-04-01

Space exploration and terraforming nearby planets have been fascinating concepts for the longest time. Nowadays, that technological advancements with regard to space exploration are thriving, it is only a matter of time before humans can start colonizing nearby moons and planets. This paper presents a state-of-the-art literature review on recent developments of "space-native" construction materials, and highlights evolutionary design concepts for "space-resilient" structures (i.e., colonies and habitats). This paper also details effects of harsh (and unique) space environments on various terrestrial and extraterrestrial construction materials, as well as on space infrastructure and structural systems. The feasibility of exploiting available space resources in terms of "in-situ resource utilization" and "harvesting of elements and compounds", as well as emergence of enabling technologies such as "cultured (lab-grown)" space construction materials are discussed. Towards the end of the present review, number of limitations and challenges facing Lunar and Martian exploration, and venues in-need for urgent research are identified and examined.

SIM PlanetQuest: The TOM-3 (Thermo-Optical-Mechanical) Siderostat Mirror Test

Science.gov (United States)

Phillips, Charles J.

2006-01-01

This slide presentation reviews the Space Interferometry Mission (SIM) PlanetQuest mission. It describes the mission, shows diagrams of the instrument, the collector bays, the Siderostat mirrors, the COL bay thermal environment, the TOM-3 replicating COL Bay Environment, the thermal hardware for the SID heater control, and the results of the test are shown

EFFECT OF UV RADIATION ON THE SPECTRAL FINGERPRINTS OF EARTH-LIKE PLANETS ORBITING M STARS

Energy Technology Data Exchange (ETDEWEB)

Rugheimer, S. [Harvard Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Kaltenegger, L. [Carl Sagan Institute, Cornell University, Ithaca, NY 14853 (United States); Segura, A. [Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, México (Mexico); Linsky, J. [JILA, University of Colorado and NIST, 440 UCB, Boulder, CO 80309-0440 (United States); Mohanty, S. [Imperial College London, 1010 Blackett Lab, Prince Consort Road, London SW7 2AZ (United Kingdom)

2015-08-10

We model the atmospheres and spectra of Earth-like planets orbiting the entire grid of M dwarfs for active and inactive stellar models with T{sub eff} = 2300 K to T{sub eff} = 3800 K and for six observed MUSCLES M dwarfs with UV radiation data. We set the Earth-like planets at the 1 AU equivalent distance and show spectra from the visible to IR (0.4–20 μm) to compare detectability of features in different wavelength ranges with the James Webb Space Telescope and other future ground- and spaced-based missions to characterize exo-Earths. We focus on the effect of UV activity levels on detectable atmospheric features that indicate habitability on Earth, namely, H{sub 2}O, O{sub 3}, CH{sub 4}, N{sub 2}O, and CH{sub 3}Cl. To observe signatures of life—O{sub 2}/O{sub 3} in combination with reducing species like CH{sub 4}—we find that early and active M dwarfs are the best targets of the M star grid for future telescopes. The O{sub 2} spectral feature at 0.76 μm is increasingly difficult to detect in reflected light of later M dwarfs owing to low stellar flux in that wavelength region. N{sub 2}O, another biosignature detectable in the IR, builds up to observable concentrations in our planetary models around M dwarfs with low UV flux. CH{sub 3}Cl could become detectable, depending on the depth of the overlapping N{sub 2}O feature. We present a spectral database of Earth-like planets around cool stars for directly imaged planets as a framework for interpreting future light curves, direct imaging, and secondary eclipse measurements of the atmospheres of terrestrial planets in the habitable zone to design and assess future telescope capabilities.

EFFECT OF UV RADIATION ON THE SPECTRAL FINGERPRINTS OF EARTH-LIKE PLANETS ORBITING M STARS

International Nuclear Information System (INIS)

Rugheimer, S.; Kaltenegger, L.; Segura, A.; Linsky, J.; Mohanty, S.

2015-01-01

We model the atmospheres and spectra of Earth-like planets orbiting the entire grid of M dwarfs for active and inactive stellar models with T eff = 2300 K to T eff = 3800 K and for six observed MUSCLES M dwarfs with UV radiation data. We set the Earth-like planets at the 1 AU equivalent distance and show spectra from the visible to IR (0.4–20 μm) to compare detectability of features in different wavelength ranges with the James Webb Space Telescope and other future ground- and spaced-based missions to characterize exo-Earths. We focus on the effect of UV activity levels on detectable atmospheric features that indicate habitability on Earth, namely, H 2 O, O 3 , CH 4 , N 2 O, and CH 3 Cl. To observe signatures of life—O 2 /O 3 in combination with reducing species like CH 4 —we find that early and active M dwarfs are the best targets of the M star grid for future telescopes. The O 2 spectral feature at 0.76 μm is increasingly difficult to detect in reflected light of later M dwarfs owing to low stellar flux in that wavelength region. N 2 O, another biosignature detectable in the IR, builds up to observable concentrations in our planetary models around M dwarfs with low UV flux. CH 3 Cl could become detectable, depending on the depth of the overlapping N 2 O feature. We present a spectral database of Earth-like planets around cool stars for directly imaged planets as a framework for interpreting future light curves, direct imaging, and secondary eclipse measurements of the atmospheres of terrestrial planets in the habitable zone to design and assess future telescope capabilities

Our Mission to Planet Earth: A guide to teaching Earth system science

Science.gov (United States)

1994-01-01

Volcanic eruptions, hurricanes, floods, and El Nino are naturally occurring events over which humans have no control. But can human activities cause additional environmental change? Can scientists predict the global impacts of increased levels of pollutants in the atmosphere? Will the planet warm because increased levels of greenhouse gases, produced by the burning of fossil fuels, trap heat and prevent it from being radiated back into space? Will the polar ice cap melt, causing massive coastal flooding? Have humans initiated wholesale climatic change? These are difficult questions, with grave implications. Predicting global change and understanding the relationships among earth's components have increased in priority for the nation. The National Aeronautics and Space Administration (NASA), along with many other government agencies, has initiated long-term studies of earth's atmosphere, oceans, and land masses using observations from satellite, balloon, and aircraft-borne instruments. NASA calls its research program Mission to Planet Earth. Because NASA can place scientific instruments far above earth's surface, the program allows scientists to explore earth's components and their interactions on a global scale.

Moessbauer spectroscopy in space

Energy Technology Data Exchange (ETDEWEB)

Klingelhoefer, G [Technische Hochschule Darmstadt (Germany). Inst. fuer Kernphysik; Held, P [Technische Hochschule Darmstadt (Germany). Inst. fuer Kernphysik; Teucher, R [Technische Hochschule Darmstadt (Germany). Inst. fuer Kernphysik; Schlichting, F [Technische Hochschule Darmstadt (Germany). Inst. fuer Kernphysik; Foh, J [Technische Hochschule Darmstadt (Germany). Inst. fuer Kernphysik; Kankeleit, E [Technische Hochschule Darmstadt (Germany). Inst. fuer Kernphysik

1995-03-01

Nearly 40 years after the discovery of the Moessbauer effect for the first time a Moessbauer spectrometer will leave our planet to explore in situ the surface of another solar system body: the red planet Mars [1]. We are currently developing a miniaturized Moessbauer spectrometer (MIMOS) which is part of the scientific payload of the Russian Mars96 mission, to be launched within the next 2-4 years [2,3]. To fulfill the requirements for a space mission to the planet Mars, all parts of the spectrometer had to be extremely miniaturized and ruggedized to withstand the space flight and Mars environmental conditions. The relevant parts (e.g. drive, detector system, electronics etc.) will be described in more detail and its characteristics compared to standard systems. Because of this new development there now is a growing interest to include a Moessbauer (MB) instrument in future space missions to other solar system bodies as for instance Venus, the terrestrial Moon, and a comet nucleus. Because of extremely different environmental conditions (e.g. nearly zero gravity on the surface of a comet nucleus, high pressure and temperature on the surface of Venus, etc.) different instrument designs and concepts are required for different missions. We will present some ideas for various types of missions, as well as the motivation for using Moessbauer spectroscopy in these cases. (orig.)

Increasing specialty care access through use of an innovative home telehealth-based spinal cord injury disease management protocol (SCI DMP).

Science.gov (United States)

Woo, Christine; Seton, Jacinta M; Washington, Monique; Tomlinson, Suk C; Phrasavath, Douangmala; Farrell, Karen R; Goldstein, Barry

2016-01-01

A spinal cord injury disease management protocol (SCI DMP) was developed to address the unique medical, physical, functional, and psychosocial needs of those living with spinal cord injuries and disorders (SCI/D). The SCI DMP was piloted to evaluate DMP clinical content and to identify issues for broader implementation across the Veterans Affairs (VA) SCI System of Care. Thirty-three patients with SCI/D from four VA SCI centers participated in a 6-month pilot. Patients received customized SCI DMP questions through a data messaging device (DMD). Nurse home telehealth care coordinators (HTCC) monitored responses and addressed clinical alerts daily. One site administered the Duke Severity of Illness (DUSOI) Checklist and Short Form-8 (SF-8™) to evaluate the changes in comorbidity severity and health-related quality of life while on the SCI DMP. Patients remained enrolled an average of 116 days, with a mean response rate of 56%. The average distance between patient's home and their VA SCI center was 59 miles. Feedback on SCI DMP content and the DMD included requests for additional clinical topics, changes in administration frequency, and adapting the DMD for functional impairments. Improvement in clinical outcomes was seen in a subset of patients enrolled on the SCI DMP. SCI HTCCs and patients reported that the program was most beneficial for newly injured patients recently discharged from acute rehabilitation that live far from specialty SCI care facilities. SCI DMP content changes and broader implementation strategies are currently being evaluated based on lessons learned from the pilot.

Evolutionary tracks of the terrestrial planets

International Nuclear Information System (INIS)

Matsui, Takafumi; Abe, Yutaka

1987-01-01

On the basis of the model proposed by Matsui and Abe, the authors show that two major factors - distance from the Sun and the efficiency of retention of accretional energy - control the early evolution of the terrestrial planets. A diagram of accretional energy versus the optical depth of a proto-atmosphere provides a means to follow the evolutionary track of surface temperature of the terrestrial planets and an explanation for why the third planet in our solar system is an 'aqua'-planet. 15 refs; 3 figs

Infrared radiation from an extrasolar planet

OpenAIRE

Deming, Drake; Seager, Sara; Richardson, L. Jeremy; Harrington, Joseph

2005-01-01

A class of extrasolar giant planets - the so-called `hot Jupiters' - orbit within 0.05 AU of their primary stars. These planets should be hot and so emit detectable infrared radiation. The planet HD 209458b is an ideal candidate for the detection and characterization of this infrared light because it is eclipsed by the star. This planet has an anomalously large radius (1.35 times that of Jupiter), which may be the result of ongoing tidal dissipation, but this explanation requires a non-zero o...

Documentation of preventive care for pressure ulcers initiated during annual evaluations in SCI.

Science.gov (United States)

Guihan, Marylou; Murphy, Deidre; Rogers, Thea J; Parachuri, Ramadevi; Sae Richardson, Michael; Lee, Kenneth K; Bates-Jensen, Barbara M

2016-05-01

Community-acquired pressure ulcers (PrUs) are a frequent cause of hospitalization of Veterans with spinal cord injury (SCI). The Veterans Health Administration (VHA) recommends that SCI annual evaluations include assessment of PrU risk factors, a thorough skin inspection and sharing of recommendations for PrU prevention strategies. We characterized consistency of preventive skin care during annual evaluations for Veterans with SCI as a first step in identifying strategies to more actively promote PrU prevention care in other healthcare encounters. Retrospective cross-sectional observational design, including review of electronic medical records for 206 Veterans with SCI admitted to 2 VA SCI centers from January-December, 2011. Proportion of applicable skin health elements documented (number of applicable elements/skin health elements documented). Our sample was primarily white (78%) male (96.1%), and mean age = 61 years. 40% of participants' were hospitalized for PrU treatment, with a mean of 294 days (median = 345 days) from annual evaluation to the index admission. On average, Veterans received an average of 75.5% (IQR 68-86%) of applicable skin health elements. Documentation of applicable skin health elements was significantly higher during inpatient vs. outpatient annual evaluations (mean elements received = 80.3% and 64.3%, respectively, P > 0.001). No significant differences were observed in documentation of skin health elements by Veterans at high vs. low PrU risk. Additional PrU preventive care in the VHA outpatient setting may increase identification and detection of PrU risk factors and early PrU damage for Veterans with SCI in the community, allowing for earlier intervention.

Terrestrial Planet Space Weather Information: An Update

Science.gov (United States)

Luhmann, J. G.; Li, Y.; Lee, C.; Mays, M. L.; Odstrcil, D.; Jian, L.; Galvin, A. B.; Mewaldt, R. A.; von Rosenvinge, T. T.; Russell, C. T.; Halekas, J. S.; Connerney, J. E. P.; Jakosky, B. M.; Thompson, W. T.; Baker, D. N.; Dewey, R. M.; Zheng, Y.; Holmstrom, M.; Futaana, Y.

2015-12-01

Space weather research is now a solar system-wide enterprise. While with the end of the Venus Express Express mission and MESSENGER, we lost our 'inside' sentinels, new missions such as Solar Orbiter and SPP, and Bepi-Colombo will soon be launched and operating. In the meantime the combination of L1 resources (ACE,WIND,SOHO) and STEREO-A at 1 AU, and Mars Express and MAVEN missions at ~1.5 AU, provide opportunities. Comparative conditions at the Earth orbit and Mars orbit locations are of special interest because they are separated by the region where most solar wind stream interaction regions develop. These alter the propagation of disturbances including the interplanetary CME-driven shocks that make the space radiation affecting future Human mission planning. We share some observational and modeling results thatillustrate present capabilities, as well as developing ones such as ENLIL-based SEP event models that use a range of available observations.

The hunt for Planet X

International Nuclear Information System (INIS)

Croswell, Ken.

1990-01-01

This article examines the hypothesis that an, as yet unobserved, planet, beyond the orbit of Pluto is responsible for peculiarities in the orbits of Uranus and Neptune. A brief overview of the discovery and observation of the outer planets is offered. The evidence for and against the proposition is noted, and the work of two present day scientists, is mentioned both of whom agree with the idea, and are searching for optical proof of the planet's existence. U.K

Debris disks as signposts of terrestrial planet formation. II. Dependence of exoplanet architectures on giant planet and disk properties

Science.gov (United States)

Raymond, S. N.; Armitage, P. J.; Moro-Martín, A.; Booth, M.; Wyatt, M. C.; Armstrong, J. C.; Mandell, A. M.; Selsis, F.; West, A. A.

2012-05-01

We present models for the formation of terrestrial planets, and the collisional evolution of debris disks, in planetary systems that contain multiple marginally unstable gas giants. We previously showed that in such systems, the dynamics of the giant planets introduces a correlation between the presence of terrestrial planets and cold dust, i.e., debris disks, which is particularly pronounced at λ ~ 70 μm. Here we present new simulations that show that this connection is qualitatively robust to a range of parameters: the mass distribution of the giant planets, the width and mass distribution of the outer planetesimal disk, and the presence of gas in the disk when the giant planets become unstable. We discuss how variations in these parameters affect the evolution. We find that systems with equal-mass giant planets undergo the most violent instabilities, and that these destroy both terrestrial planets and the outer planetesimal disks that produce debris disks. In contrast, systems with low-mass giant planets efficiently produce both terrestrial planets and debris disks. A large fraction of systems with low-mass (M ≲ 30 M⊕) outermost giant planets have final planetary separations that, scaled to the planets' masses, are as large or larger than the Saturn-Uranus and Uranus-Neptune separations in the solar system. We find that the gaps between these planets are not only dynamically stable to test particles, but are frequently populated by planetesimals. The possibility of planetesimal belts between outer giant planets should be taken into account when interpreting debris disk SEDs. In addition, the presence of ~ Earth-mass "seeds" in outer planetesimal disks causes the disks to radially spread to colder temperatures, and leads to a slow depletion of the outer planetesimal disk from the inside out. We argue that this may explain the very low frequency of >1 Gyr-old solar-type stars with observed 24 μm excesses. Our simulations do not sample the full range of

Impact of an implanted neuroprosthesis on community ambulation in incomplete SCI.

Science.gov (United States)

Lombardo, Lisa M; Kobetic, Rudolf; Pinault, Gilles; Foglyano, Kevin M; Bailey, Stephanie N; Selkirk, Stephen; Triolo, Ronald J

2018-03-01

Test the effect of a multi-joint control with implanted electrical stimulation on walking after spinal cord injury (SCI). Single subject research design with repeated measures. Hospital-based biomechanics laboratory and user assessment of community use. Female with C6 AIS C SCI 30 years post injury. Lower extremity muscle activation with an implanted pulse generator and gait training. Walking speed, maximum distance, oxygen consumption, upper extremity (UE) forces, kinematics and self-assessment of technology. Short distance walking speed at one-year follow up with or without stimulation was not significantly different from baseline. However, average walking speed was significantly faster (0.22 m/s) with stimulation over longer distances than volitional walking (0.12 m/s). In addition, there was a 413% increase in walking distance from 95 m volitionally to 488 m with stimulation while oxygen consumption and maximum upper extremity forces decreased by 22 and 16%, respectively. Stimulation also produced significant (P ≤ 0.001) improvements in peak hip and knee flexion, ankle angle at foot off and at mid-swing. An implanted neuroprosthesis enabled a subject with incomplete SCI to walk longer distances with improved hip and knee flexion and ankle dorsiflexion resulting in decreased oxygen consumption and UE support. Further research is required to determine the robustness, generalizability and functional implications of implanted neuroprostheses for community ambulation after incomplete SCI.

The milky way and beyond stars, nebulae, and other galaxies

CERN Document Server

2010-01-01

Our Search for knowledge about the universe has been remarkable, heartbreaking, fantastical, and inspiring, and this search is just beginning. The Milky Way and Beyond is part of a 7 book series that takes readers through a virtual time warp of our discovery. From the nascent space programs of the 1960's to today's space tourism and the promise of distant planet colonization, readers will be transfixed. Throughout this journey of the mind, Earth-bound explorers gain keen insight into the celestial phenomena that have fascinated humans for centuries. Thrilling narratives about indefatigable sci

Antidepressants Are Effective in Decreasing Neuropathic Pain After SCI: A Meta-Analysis.

Science.gov (United States)

Mehta, Swati; Guy, Stacey; Lam, Tracey; Teasell, Robert; Loh, Eldon

2015-01-01

To systematically review and assess the effectiveness and safety of antidepressants for neuropathic pain among individuals with spinal cord injury (SCI). A systematic search was conducted using multiple databases for relevant articles published from 1980 to April 2014. Randomized controlled trials (RCTs) involving antidepressant treatment of neuropathic pain with ≥ 3 individuals and ≥ 50% of study population with SCI were included. Two independent reviewers selected studies based on inclusion criteria and then extracted data. Pooled analysis using Cohen's d to calculate standardized mean difference, standard error, and 95% confidence interval for primary (pain) and other secondary outcomes was conducted. Four RCTs met inclusion criteria. Of these, 2 studies assessed amitriptyline, 1 trazadone, and 1 duloxetine among individuals with neuropathic SCI pain. A small effect was seen in the effectiveness of antidepressants in decreasing pain among individuals with SCI (standardized mean difference = 0.34 ± 0.15; 95% CI, 0.05-0.62; P = .02). A number needed to treat of 3.4 for 30% or more pain relief was found by pooling 2 studies. Of these, significantly higher risk of experiencing constipation (risk ratio [RR] = 1.74; 95% CI, 1.09-2.78; P = .02) and dry mouth (RR = 1.39; 95% CI, 1.04-1.85; P = .02) was found amongst individuals receiving antidepressant treatment compared to those in the control group. The current meta-analysis demonstrates that antidepressants are effective in reducing neuropathic SCI pain. However, this should be interpreted with caution due to the limited number of studies. Further evaluation of long-term therapeutic options may be required.

Limits on the abundance of galactic planets from 5 years of planet observations

NARCIS (Netherlands)

Albrow, MD; An, J; Beaulieu, JP; Caldwell, JAR; DePoy, DL; Dominik, M; Gaudi, BS; Gould, G; Greenhill, J; Hill, K; Kane, S; Martin, R; Menzies, J; Pel, JW; Pogge, RW; Pollard, KR; Sackett, PD; Sahu, KC; Vermaak, P; Watson, R; Williams, A

2001-01-01

We search for signatures of planets in 43 intensively monitored microlensing events that were observed between 1995 and 1999. Planets would be expected to cause a short-duration (similar to1 day) deviation on the smooth, symmetric light curve produced by a single lens. We find no such anomalies and

MIGRATION THEN ASSEMBLY: FORMATION OF NEPTUNE-MASS PLANETS INSIDE 1 AU

Energy Technology Data Exchange (ETDEWEB)

Hansen, Brad M. S. [Department of Physics and Astronomy and Institute of Geophysics and Planetary Physics, University of California Los Angeles, Los Angeles, CA 90095 (United States); Murray, Norm, E-mail: hansen@astro.ucla.edu [Canadian Institute for Theoretical Astrophysics, 60 St. George Street, Toronto, Ontario (Canada)

2012-06-01

We demonstrate that the observed distribution of 'hot Neptune'/'super-Earth' systems is well reproduced by a model in which planet assembly occurs in situ, with no significant migration post-assembly. This is achieved only if the amount of mass in rocky material is {approx}50-100 M{sub Circled-Plus} interior to 1 AU. Such a reservoir of material implies that significant radial migration of solid material takes place, and that it occurs before the stage of final planet assembly. The model not only reproduces the general distribution of mass versus period but also the detailed statistics of multiple planet systems in the sample. We furthermore demonstrate that cores of this size are also likely to meet the criterion to gravitationally capture gas from the nebula, although accretion is rapidly limited by the opening of gaps in the gas disk. If the mass growth is limited by this tidal truncation, then the scenario sketched here naturally produces Neptune-mass objects with substantial components of both rock and gas, as is observed. The quantitative expectations of this scenario are that most planets in the 'hot Neptune/super-Earth' class inhabit multiple-planet systems, with characteristic orbital spacings. The model also provides a natural division into gas-rich (hot Neptune) and gas-poor (super-Earth) classes at fixed period. The dividing mass ranges from {approx}3 M{sub Circled-Plus} at 10 day orbital periods to {approx}10 M{sub Circled-Plus} at 100 day orbital periods. For orbital periods <10 days, the division is less clear because a gas atmosphere may be significantly eroded by stellar radiation.

Kepler Confirmation of Multi-Planet Systems

Science.gov (United States)

Cochran, W. D.

2011-10-01

The NASA Kepler spacecraft has detected 170 candidate multi-planet systems in the first two quarters of data released in February 2011 by Borucki et al. (2011). These systems comprise 115 double candidate systems, 45 triple candidate sys- tems, and 10 systems with 4 or more candidate planets. The architecture and dynamics of these systems were discussed by Lissauer et al. (2011), and a comparison of candidates in single- and multi-planet systems was presented by Latham et al. (2011). Proceeding from "planetary candidate" systems to confirmed and validated multi-planet systems is a difficult process, as most of these systems orbit stars too faint to obtain extremely precise (1ms-1) radial velocity confimation. Here, we discuss in detail the use of transit timing vari- ations (cf. e.g. Holman et al., 2010) to confirm planets near a mean motion resonance. We also discuss extensions to the BLENDER validation (Torres et al., 2004, 2011; Fressin et al., 2011) to validate planets in multi-planet systems. Kepler was competitively selected as the tenth Discovery mission. Funding for the Kepler Mis- sion is provided by NASA's Science Mission Direc- torate. We are deeply grateful for the very hard work of the entire Kepler team.

TIDAL EVOLUTION OF CLOSE-IN PLANETS

International Nuclear Information System (INIS)

Matsumura, Soko; Rasio, Frederic A.; Peale, Stanton J.

2010-01-01

Recent discoveries of several transiting planets with clearly non-zero eccentricities and some large obliquities started changing the simple picture of close-in planets having circular and well-aligned orbits. The two major scenarios that form such close-in planets are planet migration in a disk and planet-planet interactions combined with tidal dissipation. The former scenario can naturally produce a circular and low-obliquity orbit, while the latter implicitly assumes an initially highly eccentric and possibly high-obliquity orbit, which are then circularized and aligned via tidal dissipation. Most of these close-in planets experience orbital decay all the way to the Roche limit as previous studies showed. We investigate the tidal evolution of transiting planets on eccentric orbits, and find that there are two characteristic evolution paths for them, depending on the relative efficiency of tidal dissipation inside the star and the planet. Our study shows that each of these paths may correspond to migration and scattering scenarios. We further point out that the current observations may be consistent with the scattering scenario, where the circularization of an initially eccentric orbit occurs before the orbital decay primarily due to tidal dissipation in the planet, while the alignment of the stellar spin and orbit normal occurs on a similar timescale to the orbital decay largely due to dissipation in the star. We also find that even when the stellar spin-orbit misalignment is observed to be small at present, some systems could have had a highly misaligned orbit in the past, if their evolution is dominated by tidal dissipation in the star. Finally, we also re-examine the recent claim by Levrard et al. that all orbital and spin parameters, including eccentricity and stellar obliquity, evolve on a similar timescale to orbital decay. This counterintuitive result turns out to have been caused by a typo in their numerical code. Solving the correct set of tidal

Planetesimals and Planet Formation

Science.gov (United States)

Chambers, John

The first step in the standard model for planet formation is the growth of gravitationally bound bodies called ``planetesimals'' from dust grains in a protoplanetary disk. Currently, we do not know how planetesimals form, how long they take to form, or what their sizes and mechanical properties are. The goal of this proposal is to assess how these uncertainties affect subsequent stages of planetary growth and the kind of planetary systems that form. The work will address three particular questions: (i) Can the properties of small body populations in the modern Solar System constrain the properties of planetesimals? (ii) How do the properties of planetesimals affect the formation of giant planets? (iii) How does the presence of a water ice condensation front (the ``snow line'') in a disk affect planetesimal formation and the later stages of planetary growth? These questions will be examined with computer simulations of planet formation using new computer codes to be developed as part of the proposal. The first question will be addressed using a statistical model for planetesimal coagulation and fragmentation. This code will be merged with the proposer's Mercury N-body integrator code to model the dynamics of large protoplanets in order to address the second question. Finally, a self- consistent model of disk evolution and the radial transport of water ice and vapour will be added to examine the third question. A theoretical understanding of how planets form is one of the key goals of NASA and the Origins of Solar Systems programme. Researchers have carried out many studies designed to address this goal, but the questions of how planetesimals form and how their properties affect planet formation have received relatively little attention. The proposed work will help address these unsolved questions, and place other research in context by assessing the importance of planetesimal origins and properties for planet formation.

THE OCCURRENCE RATE OF SMALL PLANETS AROUND SMALL STARS

International Nuclear Information System (INIS)

Dressing, Courtney D.; Charbonneau, David

2013-01-01

We use the optical and near-infrared photometry from the Kepler Input Catalog to provide improved estimates of the stellar characteristics of the smallest stars in the Kepler target list. We find 3897 dwarfs with temperatures below 4000 K, including 64 planet candidate host stars orbited by 95 transiting planet candidates. We refit the transit events in the Kepler light curves for these planet candidates and combine the revised planet/star radius ratios with our improved stellar radii to revise the radii of the planet candidates orbiting the cool target stars. We then compare the number of observed planet candidates to the number of stars around which such planets could have been detected in order to estimate the planet occurrence rate around cool stars. We find that the occurrence rate of 0.5-4 R ⊕ planets with orbital periods shorter than 50 days is 0.90 +0.04 -0.03 planets per star. The occurrence rate of Earth-size (0.5-1.4 R ⊕ ) planets is constant across the temperature range of our sample at 0.51 -0.05 +0.06 Earth-size planets per star, but the occurrence of 1.4-4 R ⊕ planets decreases significantly at cooler temperatures. Our sample includes two Earth-size planet candidates in the habitable zone, allowing us to estimate that the mean number of Earth-size planets in the habitable zone is 0.15 +0.13 -0.06 planets per cool star. Our 95% confidence lower limit on the occurrence rate of Earth-size planets in the habitable zones of cool stars is 0.04 planets per star. With 95% confidence, the nearest transiting Earth-size planet in the habitable zone of a cool star is within 21 pc. Moreover, the nearest non-transiting planet in the habitable zone is within 5 pc with 95% confidence.

LARGER PLANET RADII INFERRED FROM STELLAR ''FLICKER'' BRIGHTNESS VARIATIONS OF BRIGHT PLANET-HOST STARS

International Nuclear Information System (INIS)

Bastien, Fabienne A.; Stassun, Keivan G.; Pepper, Joshua

2014-01-01

Most extrasolar planets have been detected by their influence on their parent star, typically either gravitationally (the Doppler method) or by the small dip in brightness as the planet blocks a portion of the star (the transit method). Therefore, the accuracy with which we know the masses and radii of extrasolar planets depends directly on how well we know those of the stars, the latter usually determined from the measured stellar surface gravity, log g. Recent work has demonstrated that the short-timescale brightness variations ( f licker ) of stars can be used to measure log g to a high accuracy of ∼0.1-0.2 dex. Here, we use flicker measurements of 289 bright (Kepmag < 13) candidate planet-hosting stars with T eff = 4500-6650 K to re-assess the stellar parameters and determine the resulting impact on derived planet properties. This re-assessment reveals that for the brightest planet-host stars, Malmquist bias contaminates the stellar sample with evolved stars: nearly 50% of the bright planet-host stars are subgiants. As a result, the stellar radii, and hence the radii of the planets orbiting these stars, are on average 20%-30% larger than previous measurements had suggested