NASA Technical Reports Server (NTRS)
Drechsel, H. (Editor); Rahe, J. (Editor); Kondo, Y. (Editor)
1987-01-01
Papers are presented on the formation and evolution of low-mass close binaries with compact components, the periods of cataclysmic variables, multiwavelength observations of dwarf novae during outbursts, and radio emission from cataclysmic variables. Also considered are long-term optical photometry of the dwarf nova VW Hyi, periodic modulations in the optical light curves of EX Hydrae, and Echelle-Mepsicron time-resolved spectroscopy of the dwarf nova SS Cygni. Other topics include UV and X-ray observations of cataclysmic variables, new EXOSAT observations of TV Columbae, accretion disk evolution, and the boundary layer in cataclysmic variables.
NASA Astrophysics Data System (ADS)
Hellier, Coel
2001-01-01
Cataclysmic variable stars are the most variable stars in the night sky, fluctuating in brightness continually on timescales from seconds to hours to weeks to years. The changes can be recorded using amateur telescopes, yet are also the subject of intensive study by professional astronomers. That study has led to an understanding of cataclysmic variables as binary stars, orbiting so closely that material transfers from one star to the other. The resulting process of accretion is one of the most important in astrophysics. This book presents the first account of cataclysmic variables at an introductory level. Assuming no previous knowledge of the field, it explains the basic principles underlying the variability, while providing an extensive compilation of cataclysmic variable light curves. Aimed at amateur astronomers, undergraduates, and researchers, the main text is accessible to those with no mathematical background, while supplementary boxes present technical details and equations.
Detecting Nova Shells around known Cataclysmic Variable systems
NASA Astrophysics Data System (ADS)
Xhakaj, Enia; Kupfer, Thomas; Prince, Thomas A.
2017-01-01
Nova shells are hydrogen-rich nebulae around Cataclysmic Variables that are created when a Nova outburst takes place. Learning more about Nova shells can help us get a better understanding of the long-term evolution of white dwarfs in active Cataclysmic Variables. In this project, we present the search for Nova shells around 1700 Cataclysmic Variables, using Hα images from the Palomar Transient Factory (PTF) survey. The PTF Hα survey started in 2009 using the 48’’ Oschin telescope at Palomar Observatory and is the first of its type covering the whole northern hemisphere while reaching 18 mags in 60 seconds of exposure. We concentrated our search on the IAU catalogue of Historical Novae, as well as on the SDSS and the Ritter-Kolb catalogue of Cataclysmic Variables. We numerically analyzed radial profiles centered on the target sources to search for excess emission potentially associated with the shells. Out of 1700 Cataclysmic Variables present in these catalogues, we detected 25 Nova shells, out of which 20 are not observed before.
The SW Sex Phenomenon as an Evolutionary Stage of Cataclysmic Variables
NASA Astrophysics Data System (ADS)
Schmidtobreick, L.
From recent large observing campaigns, one finds that nearly all non- or weakly magnetic cataclysmic variables in the orbital period range between 2.8 and 4 hours are of SW Sex type and as such experience very high mass transfer rates. The evolution of cataclysmic variables as for any interacting binary is driven by angular momentum loss which results in a decrease of the orbital period on evolutionary time scales. In particular, all long-period systems need to cross the SW Sex regime of the orbital period distribution before entering the period gap. This makes the SW Sex phenomenon an evolutionary stage in the life of a cataclysmic variable. Here, I present a short overview of the current state of research on these systems.
1RXS J180834.7+101041 is a new cataclysmic variable with non-uniform disc
NASA Astrophysics Data System (ADS)
Yakin, D. G.; Suleimanov, V. F.; Shimansky, V. V.; Borisov, N. V.; Bikmaev, I. F.; Sakhibullin, N. A.
2010-11-01
Results of photometric and spectroscopic investigations of the recently discovered disc cataclysmic variable star 1RXS J180834.7+101041 are presented. Emission spectra of the system show broad double peaked hydrogen and helium emission lines. Doppler maps for the hydrogen lines demonstrate strongly non-uniform emissivity distribution in the disc, similar to that found in IP Peg. It means that the system is a new cataclysmic variable with a spiral density wave in the disc. Masses of the components (MWD = 0.8+/-0.22 Msolar and MRD = 0.14+/-0.02 Msolar), and the orbit inclination (i = 78°+/- 1.°5) were estimated using the various well-known relations for cataclysmic variables.
New White Dwarfs and Cataclysmic Variables from the FBS
NASA Astrophysics Data System (ADS)
Mickaelian, Areg M.
The Second part of the First Byurakan Survey (FBS) is the continuation of the Markarian Survey and is aimed at discovery of UVX stellar objects: QSOs Seyferts white dwarfs hot subdwarfs cataclysmic variables etc. +33o<δ<+45o and +61o<δ<+90o regions at |b|>15o has been covered so far. 1103 blue stellar objects have been selected including 716 new ones. Observations with the Byurakan 2.6m SAO (Russia) 6m and Haute-Provence 1.93m telescopes revealed more than 50 new white dwarfs and 7 cataclysmic variables including a new bright (V=12.6) novalike cataclysmic variable of SW Sex subclass RXS J16437+3402 found by cross-correlation of ROSAT/USNO objects and further inspection of the FBS spectra and having a period within the period ``gap"" for such objects. The white dwarfs are being studied to reveal pulsating ones (ZZ Ceti stars) magnetic WDs polars (AM Her type objects) planetary nebulae nuclei (DO stars PG 1159 type objects) etc. Polarimetric observations have been undertaken as well: FBS 1704+347 is found to be a possible polar and FBS 1815+381 a variable magnetic WD. The total number of WDs is estimated to be 270 in the whole sample (24%) and cataclysmic variables - 35 (3%)
Investigation of the new cataclysmic variable 1RXS J180834.7+101041
NASA Astrophysics Data System (ADS)
Yakin, D. G.; Suleimanov, V. F.; Borisov, N. V.; Shimanskii, V. V.; Bikmaev, I. F.
2011-12-01
We present the results of our photometric and spectroscopic studies of the new eclipsing cataclysmic variable star 1RXS J180834.7+101041. Its spectrum exhibits double-peaked hydrogen and helium emission lines. The Doppler maps constructed from hydrogen lines show a nonuniform distribution of emission in the disk similar to that observed in IP Peg. This suggests that the object can be a cataclysmic variable with tidal density waves in the disk. We have determined the component masses ( M WD = 0.8 ± 0.22 M ⊙ and M RD = 0.14 ± 0.02 M ⊙) and the binary inclination ( i = 78° ± 1.5°) based on well-known relations between parameters for cataclysmic variable stars. We have modeled the binary light curves and showed that the model of a disk with two spots is capable of explaining the main observed features of the light curves.
Twenty Years of Work with Janet Mattei on Cataclysmic Variables
NASA Astrophysics Data System (ADS)
Szkody, P.
2005-08-01
Janet Mattei and the AAVSO database have had a large impact on the field of cataclysmic variables, especially in the areas of outburst light curves of dwarf novae and ground-based support of space observations. A summary of some of the major results from AAVSO data during the last 20 years is presented.
The intermediate-age pre-cataclysmic variables SDSS J172406+562003 and RE J2013+4002
NASA Astrophysics Data System (ADS)
Shimansky, V. V.; Borisov, N. V.; Nurtdinova, D. N.; Mitrofanova, A. A.; Vlasyuk, V. V.; Spiridonova, O. I.
2012-06-01
We have analyzed the physical status of the pre-cataclysmic variables SDSSJ172406+562003 and RE J2013+4002, which have evolved after their common-envelope stage a time t = 106-107 years. Spectroscopy and photometry of these systems were performed with the 6-m and 1-m telescopes of the Special Astrophysical Observatory. We demonstrate that emission lines in the spectra were formed solely by the reflection of radiation emitted by the white dwarfs on the surfaces of their cool companions, under conditions close to local thermodynamic equilibrium. These effects are also responsible for most of the objects' photometric variability amplitude. However, comparing the light curves of SDSS 172406 from different epochs, we find aperiodic brightness variations, probably due to spottedness of the surface of the secondary. Jointly analyzing the spectra, radial-velocity curves, and light curves of the pre-cataclysmic variables and modeling the reflection effects, we have derived their fundamental parameters. We demonstrate that the secondaries in these systems are consistent with evolutionary models for main-sequence stars and do not have the luminosity excesses characteristic of cool stars in young pre-cataclysmic variables.
Radio emission of cataclysmic variable stars
NASA Technical Reports Server (NTRS)
Fuerst, E.; Benz, A.; Hirth, W.; Geffert, M.; Kiplinger, A.
1986-01-01
Eight cataclysmic variable stars were observed at 6 cm wavelength using the Very Large Array (VLA). The objects were: CN-Ori, SS-Aur, YZ-Cnc, SU-Uma, Z-Cam, V603-Aql, EM-Cyg, and RZ-Sge. Most of these objects were in optical high stage, but none were detected beyond flux limits between 0.1 and 0.3 mJy.
Cataclysmic variables and related objects
NASA Technical Reports Server (NTRS)
Hack, Margherita; Ladous, Constanze; Jordan, Stuart D. (Editor); Thomas, Richard N. (Editor); Goldberg, Leo; Pecker, Jean-Claude
1993-01-01
This volume begins with an introductory chapter on general properties of cataclysmic variables. Chapters 2 through 5 of Part 1 are devoted to observations and interpretation of dwarf novae and nova-like stars. Chapters 6 through 10, Part 2, discuss the general observational properties of classical and recurrent novae, the theoretical models, and the characteristics and models for some well observed classical novae and recurrent novae. Chapters 11 through 14 of Part 3 are devoted to an overview of the observations of symbiotic stars, to a description of the various models proposed for explaining the symbiotic phenomenon, and to a discussion of a few selected objects, respectively. Chapter 15 briefly examines the many unsolved problems posed by the observations of the different classes of cataclysmic variables and symbiotic stars.
The cataclysmic variable AE Aquarii: orbital variability in V band
NASA Astrophysics Data System (ADS)
Zamanov, R.; Latev, G.
2017-07-01
We present 62.7 hours observations of the cataclysmic variable AE Aqr in Johnson V band. These are non-published archive electro-photometric data obtained during the time period 1993 to 1999. We construct the orbital variability in V band and obtain a Fourier fit to the double-wave quiescent light curve. The strongest flares in our data set are in phase interval 0.6 - 0.8. The data can be downloaded from http://www.astro.bas.bg/~rz/DATA/AEAqr.elphot.dat.
NASA Technical Reports Server (NTRS)
Patterson, Joseph
1993-01-01
The status report covering the period from 1 June 1992 to 31 May 1993 is included. Areas of research include: (1) eclipsing cataclysmic variables; (2) deep eclipses in H0928+501; (3) YY Draconis, the Whirling Dervish; and (4) new x ray pulsar candidates from HEAO-1.
Are Some Pre-Cataclysmic Variables also Post-Cataclysmic Variables?
NASA Astrophysics Data System (ADS)
Sarna, M. J.; Marks, P. B.; Smith, R. C.
1995-10-01
We propose an evolutionary scenario in which post-common-envelope binaries (PCEBs) with secondary component masses between 0.8 Msun and 1.2 M0 start semi-detached evolution almost immediately after the common-envelope (CE) phase. These systems detach due to unstable mass transfer when the secondary develops a thick convective envelope. The duration of the detached phase is a few times 108 yr, depending on the efficiency of magnetic braking and gravitational radiation. We suggest that some of the systems that have been classified as PCEBs may be in this stage of evolution and hence would be more realistically classified as pre-cataclysmic variables (PreCVs). We also propose an observational test based on measurements of the carbon and oxygen isotopic ratios from the infrared CO bands.
Studies of an x ray selected sample of cataclysmic variables. Ph.D. Thesis
NASA Technical Reports Server (NTRS)
Silber, Andrew D.
1986-01-01
Just prior to the thesis research, an all-sky survey in hard x rays with the HEAO-1 satellite and further observations in the optical resulted in a catalog of about 700 x-ray sources with known optical counterparts. This sample includes 43 cataclysmic variables, which are binaries consisting of a detached white-dwarf and a Roche lobe filling companion star. This thesis consists of studies of the x-ray selected sample of catalcysmic variables.
NASA Astrophysics Data System (ADS)
McArthur, B. E.; Benedict, G. F.; Lee, J.; Lu, C.-L.; van Altena, W. F.; Deliyannis, C. P.; Girard, T.; Fredrick, L. W.; Nelan, E.; Duncombe, R. L.; Hemenway, P. D.; Jefferys, W. H.; Shelus, P. J.; Franz, O. G.; Wasserman, L. H.
1999-07-01
RW Triangulum (RW Tri) is a 13th magnitude nova-like cataclysmic variable star with an orbital period of 0.2319 days (5.56 hr). Infrared observations of RW Tri indicate that its secondary is most likely a late-K dwarf (Dhillon). Past analyses predicted a distance of 270 pc, derived from a blackbody fit to the spectrum of the central part of the disk (Rutten, van Paradijs, & Tinbergen). Recently completed Hubble Space Telescope Fine Guidance Sensor interferometric observations allow us to determine the first trigonometric parallax to RW Tri. This determination puts the distance of RW Tri at 341-31+38, one of the most distant objects with a direct parallax measurement. We compare our result with methods previously employed to estimate distances to cataclysmic variables.
Identification of Hard X-ray Sources in Galactic Globular Clusters: Simbol-X Simulations
NASA Astrophysics Data System (ADS)
Servillat, M.
2009-05-01
Globular clusters harbour an excess of X-ray sources compared to the number of X-ray sources in the Galactic plane. It has been proposed that many of these X-ray sources are cataclysmic variables that have an intermediate magnetic field, i.e. intermediate polars, which remains to be confirmed and understood. We present here several methods to identify intermediate polars in globular clusters from multiwavelength analysis. First, we report on XMM-Newton, Chandra and HST observations of the very dense Galactic globular cluster NGC 2808. By comparing UV and X-ray properties of the cataclysmic variable candidates, the fraction of intermediate polars in this cluster can be estimated. We also present the optical spectra of two cataclysmic variables in the globular cluster M 22. The HeII (4868 Å) emission line in these spectra could be related to the presence of a magnetic field in these objects. Simulations of Simbol-X observations indicate that the angular resolution is sufficient to study X-ray sources in the core of close, less dense globular clusters, such as M 22. The sensitivity of Simbol-X in an extended energy band up to 80 keV will allow us to discriminate between hard X-ray sources (such as magnetic cataclysmic variables) and soft X-ray sources (such as chromospherically active binaries).
Is WD 1437-008 a cataclysmic variable?
NASA Astrophysics Data System (ADS)
Shimansky, V. V.; Nurtdinova, D. N.; Borisov, N. V.; Spiridonova, O. I.
2011-10-01
Comprehensive observations of a close binary candidate WD 1437-008 are performed. The shape and amplitude of the observed brightness variations are shown to be inconsistent with the hypothesis of reflection effects, and the photometric period of the system, P phot = 0. d 2775, is found to differ from the period of spectral variations, P sp = 0. d 272060. As a result, WD 1437-008 has been preliminarily classified as a low-inclination cataclysmic variable.
NASA Astrophysics Data System (ADS)
Giovannelli, Franco; Sabau-Graziati, Lola
This paper is the updated version of that published in the proceedings of the Integral/Bart Workshop 2011 (Giovannelli & Sabau-Graziati, 2012a). SS Cyg is a cataclysmic variable usually classified as dwarf nova, a subclass of the non-magnetic cataclysmic variables. The goal of this paper is to demonstrate -- on the basis of the many arguments and circumstantial proofs derived from the numerous multifrequency data obtained from the SS Cyg binary system -- that such classification is wrong and that the intermediate polar nature of SS Cyg is the most probable. We derive the magnetic field intensity at the surface of the white dwarf in SS Cyg as B ≃ 1.6 ± 0.7 MG. This value is in complete agreement with the evaluation made by Fabbiano et al. (1981) (B< 1.9 MG) using simultaneous X-ray, UV, and optical data.
CVcat: An interactive database on cataclysmic variables
NASA Astrophysics Data System (ADS)
Kube, J.; Gänsicke, B. T.; Euchner, F.; Hoffmann, B.
2003-06-01
CVcat is a database that contains published data on cataclysmic variables and related objects. Unlike in the existing online sources, the users are allowed to add data to the catalogue. The concept of an ``open catalogue'' approach is reviewed together with the experience from one year of public usage of CVcat. New concepts to be included in the upcoming AstroCat framework and the next CVcat implementation are presented. CVcat can be found at http://www.cvcat.org.
X-ray and optical observations of 2 new cataclysmic variables
NASA Technical Reports Server (NTRS)
Singh, K. P.; Szkody, P.; Barrett, P.; Schlegel, E.; White, N. E.; Silber, A.; Fierce, E.; Hoard, D.; Hakala, P. J.; Piirola, V.;
1996-01-01
The light curves and spectra of two ultra soft X-ray sources are presented. The sources, WGAJ 1047.1+6335 and WGAJ 1802.1+1804 were discovered during a search using the Rosat position sensitive proportional counter (PSPC). The X-ray spectra of both objects show an unusually strong black body component with respect to the harder bremsstrahlung component. Based on the optical observations and on the analysis of the X-ray data, the two objects are identified with new AM Her type cataclysmic variables.
NASA Technical Reports Server (NTRS)
Buckley, D. A. H.; O'Donoghue, D.; Kilkenny, D.; Stobie, R. S.; Remillard, R. A.
1992-01-01
A deeply eclipsing cataclysmic variable, with an orbital period of 4.75 hr, has been discovered in the southern Edinburgh-Cape Blue Object Survey. The star, EC 19314 - 5915, lies close to the positional constraints of a previously unidentified HEAO-1 hard X-ray source, 1H1930 - 5989. Its optical spectrum is unusual in that it shows, apart from the emission lines characteristic of a novalike, or dwarf nova cataclysmic variable (Balmer, He I and He II), metallic absorption lines typical of a late-G star. The individual time-resolved spectra, with the tertiary absorption lines removed, show absorption reversals in the Balmer emission lines, increasing in strength for the higher series. The Balmer emission radial velocities are therefore severely distorted in comparison to the He II 4686-A emission and He I 4471-A absorption radial velocity curves. An independent distance estimate of about 600 pc is derived for EC19314 - 5915, from the spectroscopic parallax of the third star.
On the implications of the period distributions of subclasses of cataclysmic variables
NASA Astrophysics Data System (ADS)
Verbunt, Frank
1997-09-01
The period distributions of dwarf novae and nova-like variables above the period gap are different if the VY Scl systems are classed with the nova-like variables, but the same when the VY Scl phenomenon is classed with the dwarf nova outbursts. For the remaining nova-like variables, the period gap is no longer significant. Classification of the VY Scl phenomenon with dwarf novae suggests that dwarf nova outbursts are caused by variation in mass transfer from the donor. Absence of the period gap obviates the need for models explaining it, and invalidates one piece of evidence for the importance of magnetic braking for the evolution of cataclysmic variables and of low-mass binaries in general.
Theories of white dwarf oscillations
NASA Technical Reports Server (NTRS)
Vanhorn, H. M.
1980-01-01
The current status of theoretical understanding of the oscillations observed in the ZZ Ceti stars and cataclysmic variables is briefly reviewed. Nonradial g-mode oscillations appear to provide a satisfactory explanation for the low amplitude variables such as R548, with periods in the range of approximately 200 to 300 seconds, but for the longer period (800 to 1000 seconds) oscillators, the situation is still unclear. Rotation may play an important role in this problem, and the effects of both slow and fast rotation upon the mode structure are discussed. In the cataclysmic variables, both accretion and thermonuclear burning may act to excite oscillations of the white dwarf.
Observations of cataclysmic variables with IUE
NASA Technical Reports Server (NTRS)
Hartmann, L.; Raymond, J.
1981-01-01
Observations are reported of the cataclysmic variables AN UMa, 2AO311-227, VV Pup, DQ Her, and GK Per. Continuum emission was detected in the short wavelength region in DQ Her. This object exhibits a quasi-blackbody spectrum at short wavelengths, such blackbody components are a common property of the variables AM Her, SS Cyg, and U Gem, suggesting an underlying similarity in the activity of these diverse systems. Flat continuum components at longer wavelengths in general are not compatible with standard disk models. The emission line ratios in AE Aqr are anomalous in that C IV is absent to a very low level relative to N V.
A search for cataclysmic binaries containing strongly magnetic white dwarfs
NASA Technical Reports Server (NTRS)
Bond, H. E.; Chanmugam, G.
1982-01-01
The AM Herculis type binaries which contain accreting white dwarfs with surface magnetic fields of a few times 10 to the seventh power gauss were studied. If white dwarfs in cataclysmic binaries have a range of field strengths similar to that among single white dwarfs. AM Her like systems should exist with fields as high as 3 x 10 to the eighth power gauss. It is suggested that such objects will not have the strong optical polarization of the AM Her variables; however, they exhibit high harmonic cyclotron emission, making them spectacular UV sources. We made IUE observations of seven candidate cataclysmic variables selected for optical similarity to AM Her binaries. Although all seven objects were detected in the UV, none display unusually strong UV continua. It is suggested that the distribution of magnetic field strengths among single white dwarfs may be different from that among binaries.
Extreme Ultraviolet Explorer observations of the magnetic cataclysmic variable RE 1938-461
NASA Technical Reports Server (NTRS)
Warren, John K.; Vallerga, John V.; Mauche, Christopher W.; Mukai, Koji; Siegmund, Oswald H. W.
1993-01-01
The magnetic cataclysmic variable RE 1938-461 was observed by the Extreme Ultraviolet Explorer (EUVE) Deep Survey instrument on 1992 July 8-9 during in-orbit calibration. It was detected in the Lexan/ boron (65-190 A) band, with a quiescent count rate of 0.0062 +/- 0.0017/s, and was not detected in the aluminum/carbon (160-360 A) band. The Lexan/boron count rate is lower than the corresponding ROSAT wide-field camera Lexan/boron count rate. This is consistent with the fact that the source was in a low state during an optical observation performed just after the EUVE observation, whereas it was in an optical high state during the ROSAT observation. The quiescent count rates are consistent with a virtual cessation of accretion. Two transient events lasting about 1 hr occurred during the Lexan/boron pointing, the second at a count rate of 0.050 +/- 0.006/s. This appears to be the first detection of an EUV transient during the low state of a magnetic cataclysmic variable. We propose two possible explanations for the transient events.
Winds from accretion disks - Ultraviolet line formation in cataclysmic variables
NASA Technical Reports Server (NTRS)
Shlosman, Isaac; Vitello, Peter
1993-01-01
Winds from accretion disks in cataclysmic variable stars are ubiquitous. Observations by IUE reveal P Cygni-shaped profiles of high-ionization lines which are attributed to these winds. We have studied the formation of UV emission lines in cataclysmic variables by constructing kinematical models of biconical rotating outflows from disks around white dwarfs. The photoionization in the wind is calculated taking into account the radiation fields of the disk, the boundary layer, and the white dwarf. The 3D radiative transfer is solved in the Sobolev approximation. Effects on the line shapes of varying basic physical parameters of the wind are shown explicitly. We identify and map the resonant scattering regions in the wind which have strongly biconical character regardless of the assumed velocity and radiation fields. Rotation at the base of the wind introduces a radial shear which decreases the line optical depth and reduces the line core intensity. We find that it is possible to reproduce the observed P Cygni line shapes and make some predictions to be verified in high-resolution observations.
The 2.8-hour flux modulation of the cataclysmic variable PG1711 + 336
NASA Astrophysics Data System (ADS)
Rosen, S. R.; Branduardi-Raymont, G.; Mason, K. O.; Murdin, P. G.
1989-04-01
High-speed optical photometry of the cataclysmic variable PG1711 + 336 is used to confirm the presence of a 2.8-hour periodic modulation in the light curve of the star and to improve its ephemeris. Pronounced flickering on time-scales between 10 and 20 minutes is found superimposed on the 2.8-hour variation. Three hours of time-resolved spectroscopy of PG1711 + 336 yields evidence for a radial velocity variation in the He II 4686-A emission line at a period consistent with the 2.8-hour photometric modulation. This is in contrast with observations of the H-alpha line reported in the literature which indicate a 15-hour radial velocity modulation period. The issue of which, if either, of these periods is the orbital period of the system remains unresolved. However, an observation made using the Exosat satellite failed to detect X-ray emission from PG1711 + 336 in the 0.1-10 keV range, which argues against this object being a member of the Intermediate Polar class of magnetic cataclysmic variables.
Visualizing SPH Cataclysmic Variable Accretion Disk Simulations with Blender
NASA Astrophysics Data System (ADS)
Kent, Brian R.; Wood, Matthew A.
2015-01-01
We present innovative ways to use Blender, a 3D graphics package, to visualize smoothed particle hydrodynamics particle data of cataclysmic variable accretion disks. We focus on the methods of shape key data constructs to increasedata i/o and manipulation speed. The implementation of the methods outlined allow for compositing of the various visualization layers into a final animation. The viewing of the disk in 3D from different angles can allow for a visual analysisof the physical system and orbits. The techniques have a wide ranging set of applications in astronomical visualization,including both observation and theoretical data.
T Pyxidis: The First Cataclysmic Variable with a Collimated Jet
NASA Technical Reports Server (NTRS)
Shahbaz, T.; Livio, M.; Southwell, K. A.; Charles, P. A.
1997-01-01
We present the first observational evidence for a collimated jet in a cataclysmic variable system; the recurrent nova T Pyxidis. Optical spectra show bipolar components of H(alpha) with velocities approx. 1400 km/s, very similar to those observed in the supersoft X-ray sources and in SS 433. We argue that a key ingredient of the formation of jets in the supersoft X-ray sources and T Pyx (in addition to an accretion disk threaded by a vertical magnetic field), is the presence of nuclear burning on the surface of the white dwarf.
Mass transfer cycles in cataclysmic variables
NASA Technical Reports Server (NTRS)
King, A. R.; Frank, J.; Kolb, U.; Ritter, H.
1995-01-01
It is well known that in cataclysmic variables the mass transfer rate must fluctuate about the evolutionary mean on timescales too long to be directly observable. We show that limit-cycle behavior can occur if the radius change of the secondary star is sensitive to the instantaneous mass transfer rate. The only reasonable way in which such a dependence can arise is through irradiation of this star by the accreting component. The system oscillates between high states, in which irradiation causes slow expansion of the secondary and drives an elevated transfer rate, and low states, in which this star contracts.
AN ONLINE CATALOG OF CATACLYSMIC VARIABLE SPECTRA FROM THE FAR-ULTRAVIOLET SPECTROSCOPIC EXPLORER
DOE Office of Scientific and Technical Information (OSTI.GOV)
Godon, Patrick; Sion, Edward M.; Levay, Karen
2012-12-15
We present an online catalog containing spectra and supporting information for cataclysmic variables that have been observed with the Far-Ultraviolet Spectroscopic Explorer (FUSE). For each object in the catalog we list some of the basic system parameters such as (R.A., decl.), period, inclination, and white dwarf mass, as well as information on the available FUSE spectra: data ID, observation date and time, and exposure time. In addition, we provide parameters needed for the analysis of the FUSE spectra such as the reddening E(B - V), distance, and state (high, low, intermediate) of the system at the time it was observed.more » For some of these spectra we have carried out model fits to the continuum with synthetic stellar and/or disk spectra using the codes TLUSTY and SYNSPEC. We provide the parameters obtained from these model fits; this includes the white dwarf temperature, gravity, projected rotational velocity, and elemental abundances of C, Si, S, and N, together with the disk mass accretion rate, the resulting inclination, and model-derived distance (when unknown). For each object one or more figures are provided (as gif files) with line identification and model fit(s) when available. The FUSE spectra and the synthetic spectra are directly available for download as ASCII tables. References are provided for each object, as well as for the model fits. In this article we present 36 objects, and additional ones will be added to the online catalog in the future. In addition to cataclysmic variables, we also include a few related objects, such as a wind-accreting white dwarf, a pre-cataclysmic variable, and some symbiotics.« less
Does tidal capture produce cataclysmic variables?
NASA Technical Reports Server (NTRS)
Bailyn, Charles D.; Grindlay, Jonathan E.; Garcia, Michael R.
1990-01-01
It is shown that earlier estimates of the number of cataclysmic variables (CVs) to be expected from tidal capture in globular clusters may have been considerably too high, since many such binaries will result in unstable mass transfer, and thus not become CVs after all. In particular, CVs with white dwarf masses less than or obout 1.0 solar mass will be supressed. Such unstable mass transfer events may produce some of the cluster mass loss required to stabilize the cluster core. The smaller number of stable CVs predicted may suggest a reconsideration of the nature of some of the low-luminosity cluster X-ray sources.
Superhump and outburst activity of the cataclysmic variable RZ LMi in the U- and optical passbands
NASA Astrophysics Data System (ADS)
Shugarov, S. Y.; Katysheva, N. A.; Chochol, D.; Krushevska, V. N.; Vozyakova, O. V.
2018-05-01
An analysis of the new U,B,V,RC,IC-photometry of the cataclysmic variable RZ LMi obtained in 2016-17 showed the largest (U-B) colour excess in quiescence as well as during the decline of brightness, associated with the outbursts activity. The smallest (U-B) colour excess was found during the brightness increase from the quiescence. In contrast to the (U-B) colour index, the (B-V),(V-RC),(RC-IC) colour indices exhibits the largest colour excesses near the maximum of the outburst and the smallest during the quiescence. The (B-V) colour index showed also a large excess 1-2 days before a minimum. The detailed study of superhumps during the maximum of activity reveals the largest (U-B) colour excess at the time of the minimum brightness of superhumps. The (B-RC) colour index exhibits a similar behaviour, but with a phase shift of +0.1-{+}0.2 period of superhumps. The tracks in two-colour and colour-magnitude diagrams during superoutbursts are compared with the data for other cataclysmic variables during their outbursts as well as with published theoretical calculations.
Research of Precataclysmic Variables with Radius Excesses
NASA Astrophysics Data System (ADS)
Deminova, N. R.; Shimansky, V. V.; Borisov, N. V.; Gabdeev, M. M.; Shimanskaya, N. N.
2017-06-01
The results of spectroscopic observations of the pre-cataclysmic variable NSVS 14256825, which is a HW Vir binary system, were analyzed. The chemical composition is determined, the radial velocities and equivalent widths of a given star are measured. The fundamental parameters of the components were determined (R1 = 0.166 R⊙ , M2 = 0.100 M⊙ , R2 = 0.122 R⊙). It is shown that the secondary component has a mass close to the mass of brown dwarfs. A comparison of two close binary systems is made: HS 2333 + 3927 and NSVS 14256825. A radius-to-mass relationship for the secondary components of the studied pre-cataclysmic variables is constructed. It is concluded that an excess of radii relative to model predictions for MS stars is observed in virtually all systems.
Gamma-ray emission from Cataclysmic variables. 1: The Compton EGRET survey
NASA Technical Reports Server (NTRS)
Schlegel, Eric M.; Barrett, Paul E.; De Jager, O. C.; Chanmugam, G.; Hunter, S.; Mattox, J.
1995-01-01
We report the results of the first gamma-ray survey of cataclysmic variables (CVs) using observations obtained with the Energetic Gamma Ray Experiment Telescope (EGRET) instrument on the Compton Observatory. We briefly describe the theoretical models that are applicable to gamma-ray emission from CVs. These models are particularly relevant to magnetic CVs containing asynchronously rotating white dwarfs. No magnetic CV was detected with an upper limit on the flux at 1 GeV of approximately 2 x 10(exp -8)/sq cm/sec, which corresponds to an upper limit on the gamma-ray luminosity of approximately 10(exp 31) ergs/sec, assuming a typical CV distance of 100 pc.
Period changes of cataclysmic variables below the period gap: V2051 Oph, OY Car and Z Cha
NASA Astrophysics Data System (ADS)
Pilarčík, L.; Wolf, M.; Zasche, P.; Vraštil, J.
2018-04-01
We present our results of a long-term monitoring of cataclysmic variable stars (CVs). About 40 new eclipses were measured for the three southern SU UMa-type eclipsing CVs: V2051 Oph, OY Car and Z Cha. Based on the current O - C diagrams we confirmed earlier findings that V2051 Oph and OY Car present cyclic changes of their orbital periods lasting 25 and 29 years, respectively. In case of Z Cha we propose the light-time effect caused probably by a presence of the third component orbiting the eclipsing CV with the period of 43.5 years. The minimal mass of this companion results about 15 MJup.
On the long term evolution of white dwarfs in cataclysmic variables and their recurrence times
NASA Technical Reports Server (NTRS)
Sion, E. M.; Starrfield, S. G.
1985-01-01
The relevance of the long term quasi-static evolution of accreting white dwarfs to the outbursts of Z Andromeda-like symbiotics; the masses and accretion rates of classical nova white dwarfs; and the observed properties of white dwarfs detected optically and with IUE in low M dot cataclysmic variables is discussed. A surface luminosity versus time plot for a massive, hot white dwarf bears a remarkable similarity to the outburst behavior of the hot blue source in Z Andromeda. The long term quasi-static models of hot accreting white dwarfs provide convenient constraints on the theoretically permissible parameters to give a dynamical (nova-like) outburst of classic white dwarfs.
The nature of the cataclysmic variable PT Per
NASA Astrophysics Data System (ADS)
Watson, M. G.; Bruce, A.; MacLeod, C.; Osborne, J. P.; Schwope, A. D.
2016-08-01
We present a study of the cataclysmic variable star PT Per based on archival XMM-Newton X-ray data and new optical spectroscopy from the William Herschel Telescope (WHT) with Intermediate dispersion Spectrograph and Imaging System (ISIS). The X-ray data show deep minima which recur at a period of 82 min and a hard, unabsorbed X-ray spectrum. The optical spectra of PT Per show a relatively featureless blue continuum. From an analysis of the X-ray and optical data we conclude that PT Per is likely to be a magnetic cataclysmic variable of the polar class in which the minima correspond to those phase intervals when the accretion column rotates out of the field of view of the observer. We suggest that the optical spectrum, obtained around 4 yr after the X-ray coverage, is dominated by the white dwarf in the system, implying that PT Per was in a low accretion state at the time of the observations. An analysis of the likely system parameters for PT Per suggests a distance of ≈90 pc and a very low mass secondary, consistent with the idea that PT Per is a `period-bounce' binary. Matching the observed absorption features in the optical spectrum with the expected Zeeman components constrains the white dwarf polar field to be Bp ≈ 25-27 MG.
Spectroscopy and Photometry of EUVE J1429-38.0:An Eclipsing Magnetic Cataclysmic Variable
NASA Astrophysics Data System (ADS)
Howell, Steve B.; Craig, Nahide; Roberts, Bryce; McGee, Paddy; Sirk, Martin
1997-06-01
EUVE J1429-38.0 was originally discovered as a variable source by the Extreme Ultraviolet Explorer (EUVE) satellite. We present new optical observations which unambiguously confirm this star to be an eclipsing magnetic system with an orbital period of 4() h 46() m. The photometric data are strongly modulated by ellipsoidal variations during low states which allow a system inclination of near 80 degrees to be determined. Our time-resolved optical spectra, which cover only about one-third of the orbital cycle, indicate the clear presence of a gas stream. During high states, EUVE J1429-38.0 shows ~ 1 mag deep eclipses and the apparent formation of a partial accretion disk. EUVE J1429-38.0 presents the observer with properties of both the AM Herculis and the DQ Herculis types of magnetic cataclysmic variable.
PG 1316+678: A young pre-cataclysmic binary with weak reflection effects
NASA Astrophysics Data System (ADS)
Shimansky, V. V.; Borisov, N. V.; Bikmaev, I. F.; Sakhibullin, N. A.; Shimanskaya, N. N.; Spiridonova, O. I.; Irtuganov, E. N.
2013-03-01
The PG 1316+678 star is classified as a pre-cataclysmic binary, as is evidenced by its photometric and spectroscopic observations. Its orbital period is determined to be P orb = 3.3803d, which coincides with the photometric period. The intensities of the emission HI and HeI lines are shown to vary synchronously with the brightness of the object (Δ m V = 0.065 m , Δ m R = 0.08 m ). These variations arise as the UV radiation from the DAO white dwarf is reflected from the surface of the cold companion. The parameters of the binary are estimated and the time of its evolution after the common-envelope phase is determined to be t ≈ 240 000 years. Thus, PG 1316+678 is a young pre-cataclysmic NN Ser variable with the smallest known photometric reflection effect.
White Dwarfs in Cataclysmic Variables: An Update
Sion, Edward M.; Godon, Patrick
2018-01-01
In this review, we summarize what is currently known about the surface temperatures of accreting white dwarfs in non-magnetic and magnetic cataclysmic variables (CVs) based upon synthetic spectral analyses of far ultraviolet data. We focus only on white dwarf surface temperatures, since in the area of chemical abundances, rotation rates, WD masses and accretion rates, relatively little has changed since our last review, pending the results of a large HST GO program involving 48 CVs of different CV types. The surface temperature of the white dwarf in SS Cygni is re-examined in the light of its revised distance. We also discuss new HST spectra of the recurrent nova T Pyxidis as it transitioned into quiescence following its April 2011 nova outburst. PMID:29505036
Sonification of Kepler Field SU UMa Cataclysmic Variable Stars V344 Lyr and V1504 Cyg
NASA Technical Reports Server (NTRS)
Tutchton, Roxanne M.; Wood, Matt A.; Still, Martin D.; Howell, Steve B.; Cannizzo, John K.; Smale, Alan P.
2012-01-01
Sonification is the conversion of quantitative data into sound. In this work we explain the methods used in the sonification of light curves provided by the Kepler instrument from Q2 through Q6 for the cataclysmic variable systems V344 Lyr and V1504 Cyg . Both systems are SU UMa stars showing dwarf nova outbursts and superoutbursts as well as positive and negative superhumps. Focused sonifications were done from average pulse shapes of each superhump, and separate sonifications of the full, residual light curves were done for both stars. The audio of these data reflected distinct patterns within the evolutions of supercycles and superhumps that matched pervious observations and proved to be effective aids in data analysis.
First XMM-Newton Observations of a Cataclysmic Variable II: Spectral Studies of OY Car
NASA Technical Reports Server (NTRS)
Ramsay, Gavin; Cordova, France; Cottam, Jean; Mason, Keith; Much, Rudu; Osborne, Julian; Pandel, Dirk; Poole, Tracey; Wheatley, Peter
2000-01-01
We present XMM-Newton X-ray spectra of the disc accreting cataclysmic variable OY Car, which were obtained during the performance verification phase of the mission. These data were taken 4 days after a short outburst. In the EPIC spectra we find strong Iron K(beta) emission with weaker Iron K(alpha) emission together with Silicon and Sulphur lines. The spectra are best fitted with a three temperature plasma model with a partial covering absorber. Multiple temperature emission is confirmed by the emission lines seen in the RGS spectrum and the H/He like intensity ratio for Iron and Sulphur which imply temperatures of approx. 7keV and approx. 3keV respectively.
A study of extreme-ultraviolet emission from cataclysmic variables
NASA Technical Reports Server (NTRS)
Polidan, Ronald S.; Mauche, Christopher W.; Wade, Richard A.
1990-01-01
Voyager far- and extreme UV spectrophotometric observations of five cataclysmic variables (the dwarf novae SS Cyg and VW Hyi and the novalike variables V3885 Sgr, RW Sex, and IX Vel) are combined with neutral hydrogen column densities derived from the curve-of-growth analysis of interstellar absorption lines in high-resolution IUE spectra to place upper limits on the emitted flux in the 600-700 A EUV band. The Voyager observations of VW Hyi were obtained during both normal and superoutbursts. Detailed accretion disk model calculations show that most of the 600-700 A flux in these systems should originate in the inner accretion disk rather than in the boundary layer. For VW Hyi, the low neutral hydrogen column and excellent Voyager superoutburst data place the observed upper limit to the 600-700 A flux well below the expected EUV flux from the model calculations.
CCD time-resolved photometry of faint cataclysmic variables. I
NASA Technical Reports Server (NTRS)
Howell, Steve; Szkody, Paula
1988-01-01
CCD time-resolved V and B differential light curves are presented for the dwarf novae AR And, FS Aur, TT Boo, UZ Boo, AF Cam, AL Com, AW Gem, X Leo, RZ Leo, CW Mon, SW UMa, and TW Vir. The time-series observations ranged from 2 to 6 hours and have accuracies of 0.025 mag or better for the majority of the runs. Except for AR And, X Leo, CW Mon, and TW Vir, the periods are below the cataclysmic-variable period gap (about 2 hours), and the systems are potential SU UMa stars. Photometric periods for five of the stars are the first such determinations, while those for the other seven generally confirm previous spectroscopic or photometric observations. In several cases, the photometric modulations are large amplitude (up to 0.5 mag). The results on AL Com and SW UMa indicate they may be magnetic variables.
Unravelling the Role of the SW Sextantis Stars in the Evolution of Cataclysmic Variables
NASA Astrophysics Data System (ADS)
Torres, Manuel; Steeghs, D.; Rodriguez-Gil, P.; Gansicke, B.; Marsh Warwick, T. R.; Araujo-Betancor, S.; Long, K.
2006-08-01
SW Sextantis stars are a relatively large group of cataclysmic variables whose properties contradict all predictions made by the current CV evolution theories. Very little is known about the properties of their accreting white dwarfs and their donor stars, as the stellar components are usually outshone by an extremely bright accretion flow. Consequently, a proper assesment of their evolutionary state is illusionary. We are monitoring the brightness of 33 SW Sex stars, and request here Gemini/GMOS-N time to obtain orbital phase-resolved spectroscopy if one of them enters a low state. These data will be used to accurately measure the mass ratio, white dwarf temperature, and distance of the system, eventually providing the first detailed system parameters for any SW Sex star.
Line formation in the hot spot region of cataclysmic variable accretion disks
NASA Technical Reports Server (NTRS)
Elitzur, Moshe; Clarke, John T.; Kallman, T. R.
1988-01-01
The paper presents a theoretical analysis of the emission lines observed in the cataclysmic variable A0 Psc (=H2252-035), including detailed modeling of the hydrogen Balmer line emission. The analysis makes it possible to deduce the physical conditions in the so called 'hot spot', or 'bulge' region where the accretion column hits the rim of the accretion disk. It is concluded that the bulge is optically thick to the ionizing disk radiation. Consequently, its disk illuminated face is fully ionized whereas the side facing away from the disk is neutral, resulting in modulation of the observed emission lines with the orbital period. The density in the hot spot is about 5 x 10 to the 12th to 10 to the 13th/cu cm.
Asymmetric mass accretion in the magnetic cataclysmic variable RE 1149 + 28
NASA Technical Reports Server (NTRS)
Howell, Steve B.; Sirk, Martin M.; Malina, Roger F.; Mittaz, J. P. D.; Mason, K. O.
1995-01-01
We present the first detailed extreme photometric observations of a magnetic cataclysmic variable. Our two Extreme Ultraviolet Explorer (EUVE) observations of the AM Her star RE 1149 + 28 were obtained about 1 yr apart and show light-curve variations on orbital to yearly timescales, as well as long-term mean flux level changes of a factor of 2. The photometric data show a persistent ingress EUV enhancement which lasts approximately 0.04 in phase. We attribute this to a region of approximately 10(exp 3) km in extent at the accretion impact site, on or very near the surface of the white dwarf primary. Our observations of RE 1149 are consistent with a relatively low system inclination and provide a best-fit orbital period of 90.14 +/- 0.015 minutes.
Investigations of a New Eclipsing Cataclysmic Variable HBHA 4705-03
NASA Astrophysics Data System (ADS)
Yakin, D. G.; Suleimanov, V. F.; Shimansky, V. V.; Vlasyuk, V. V.; Spiridonova, O. I.
2013-01-01
Results of photometric and spectroscopic investigations of the recently discovered eclipsing cataclysmic variable star HBHA 4705-03 are presented. The emission spectra of the system show broad hydrogen and helium emission lines. The bright spots with an approximately zero velocity components are found in the Doppler maps for the hydrogen and ionized helium lines. The disc structure is more prominent in the maps for the neutral helium lines. The masses of the components (MWD = 0.54 ± 0.10M⊙ and MRD = 0.45 ± 0.05 M⊙), and the orbit inclination (i = 71.°8 ± 0.°7) were estimated using the radial velocity light curve and the eclipse width. The modeling of the light curve allows us to evaluate the bright spot parameters and the mass accretion rate (M ≍ 2 ·1017 g s-1).
Far UV Observations of Interstellar Shocks
NASA Technical Reports Server (NTRS)
Raymond, John C.
1998-01-01
This grant covered analysis of Hopkins Ultraviolet Telescope data from the Astro-2 mission. The proposed research was aimed primarily at SNR shock waves, but the ASTRO-2 GO program was intended to make the GOs part of the instrument teams. The grant therefore covered extensive travel to Marshall Space Flight Center for mission simulations and the mission itself. In keeping with the unique nature of the ASTRO-2 GO program, I participated actively in the instrument team's investigations of HH objects and cataclysmic variables. Over the course of the Astro-2 mission, we obtained good observations of the supernova remnants SN1006 (1 position), Vela (3 positions), the Cygnus Loop (7 positions) and 0519-69 in the LMC (1 position) as part of this GI program, along with Puppis A (1 position), Vela (1 position), the Cygnus Loop (7 positions) and the Schweizer- Middleditch star (HUT PI program on SNRS). We also observed the Herbig-Haro object HH2 and about a dozen cataclysmic variables, including magnetic systems and dwarf novae. This GI grant covered modest travel for data analysis. We anticipate submitting papers on the non-radiative shock in northern Cygnus Loop, on the LMC Balmer-dominated remnant LMC 0519-69, on the radiative shocks in the Eastern Cygnus Loop (the XA region), and on the cataclysmic variable YZ Cnc over the course of the coming year. We have obtained extensive supporting data from ground-based telescopes for the Cygnus Loop spectra.
On the Existence of Low-Luminosity Cataclysmic Variables Beyond the Orbital Period Minimum
NASA Technical Reports Server (NTRS)
Howell, Steve B.; Rappaport, Saul; Politano, Michael
1997-01-01
Models of the present-day intrinsic population of cataclysmic variables predict that 99 per cent of these systems should be of short orbital period. The Galaxy is old enough that approx. 70 per cent of these stars will have already reached their orbital period minimum (approx. 80 min), and should be evolving back toward longer periods. Mass-transfer rates in these highly evolved binaries are predicted to be less or equal to 10(exp -11), leading to M(sub V) of approx. 10 or fainter, and the secondaries would be degenerate, brown dwarf-like stars. Recent observations of a group of low-luminosity dwarf novae (TOADS) provide observational evidence for systems with very low intrinsic M,. and possibly low-mass secondaries. We carry out population synthesis and evolution calculations for a range of assumed ages of the Galaxy in order to study P(sub orb) and M distributions for comparison with the TOAD observations. We speculate that at least some of the TOADs are the predicted very low- luminosity, post-period-minimum cataclysmic variables containing degenerate (brown dwarf-like) secondaries having masses between 0.02 and 0.06 M, and radii near 0.1 R., We show that these low-luminosity systems are additionally interesting in that they can be used to set a lower limit on the age of the Galaxy. The TOAD with the longest orbital period currently known (123 min), corresponds to a Galaxy age of at least 8.6 x 10(exp 9) yr.
Short-period cataclysmic variables at Observatorio Astronomico Nacional IA UNAM.
NASA Astrophysics Data System (ADS)
Zharikov, S.
2014-03-01
We present results of time-resolved spectroscopy and photometry of faint (∼17-19 mag) Cataclysmic Variable stars with periods around the minimum orbital period (∼80 min). In this work we concentrated to our results of study of CVs systems which have evolved beyond the period minimum (so-called bounce-back systems). Using various instruments attached to 2.1m, 1.5m and 0.84m telescopes of OAN SPM of IA UNAM we explored conditions and structure of accretion disks in those short-period Cataclysmic Variables. We showed that the accretion disk in a system with an extremely low mass ratio (≤0.05) grows in the size reaching 2:1 resonance radius and is relatively cool. The disk in such systems also becomes largely optically thin in the continuum, contributing to the total flux less than the stellar components of the system. In contrast, the viscosity and the temperature in spiral arms formed at the outer edge of the disk are higher and their contribution in continuum plays an increasingly important role. We model such disks and generate light curves which successfully simulate the observed double-humped light curves in the quiescence. Thanks to support of our programs by the Time Allocation Commission of OAN SPM, the perfect astroclimate in the observatory, and the phase-locked method of spectroscopic observations, the significant progress in the study of bounce-back systems using a small size telescope was reached.
Period changes of the long-period cataclysmic binary EX Draconis
NASA Astrophysics Data System (ADS)
Pilarčík, L.; Wolf, M.; Dubovský, P. A.; Hornoch, K.; Kotková, L.
2012-03-01
The cataclysmic variable star EX Dra is a relatively faint but frequently investigated eclipsing dwarf nova. In total 35 new eclipses were measured photometrically as part of our long-term monitoring of interesting eclipsing systems. Using published and new mid-eclipse times obtained between 2004 and 2011 we constructed the observed-minus-calculated diagram. The current data present 21 years of period modulation with a semi-amplitude of 2.5 min. The eclipse timings show significant deviations from the best sinusoidal fit, which indicates that this ephemeris is not a complete description of the data. The fractional period change is roughly ΔP/P = 3 × 10-6.
Observations of TT Ari requested in support of MOST observations
NASA Astrophysics Data System (ADS)
Waagen, Elizabeth O.
2012-08-01
Dr. Nikolaus Vogt (Universidad de Valparaiso, Chile) requested simultaneous photometry and spectroscopy of the novalike (VY Scl subtype) cataclysmic variable TT Ari in support of upcoming observations with the Canadian Microvariability and Oscillations of Stars (MOST) satellite 2012 September 13 through October 20. The Departamento de Fisica y Astronomia of the Valparaiso University will carry out photometry with small telescopes in central Chile but the assistance of other observers, particularly in other latitudes and longitudes, is requested. The observations are being carried out to study superhump behavior, which is still not well understood despite the amount of research done in all classes of cataclysmic variables. TT Ari exibits superhumps - both positive (the superhump period is longer than the orbital period) and negative (the superhump period is shorter than the orbital period). While positive superhumps are thought probably to be the result of an eccentric configuration in the accretion disk, the mechanism for negative superhumps is not yet understood except that it may be related to the disk's being warped out of the orbital plane, leading to complex torque phenomena. TT Ari, one of the brightest cataclysmic variables, exhibits occasional fadings of several magnitudes, from its usual high-state (maximum) magnitude of ~10.5V to a low-state magnitude as faint as 16V. These fadings occur every 20-25 years, and last between 500 and 1000 days. According to observations in the AAVSO International Database, TT Ari is currently magnitude 10.5V. Finder charts with sequence may be created using the AAVSO Variable Star Plotter (http://www.aavso.org/vsp). Observations should be submitted to the AAVSO International Database. See full Alert Notice for more details, particularly regarding goals of the campaign, and observing instructions.
Intervening Variables in the TV Violence-Aggression Relation: Evidence from Two Countries.
ERIC Educational Resources Information Center
Huesmann, L. Rowell; And Others
1984-01-01
A longitudinal, cross-cultural field study was made to determine boundary conditions under which the television violence/aggression relation obtains, to determine intervening variables, and to illuminate the process through which television violence relates to aggression. Children from first through fifth grades in the United States, Australia,…
NASA Technical Reports Server (NTRS)
Szkody, Paula
1987-01-01
IUE time-resolved spectra of the high-inclination cataclysmic variables IP Peg, PG 1030+590, and V1315 Aql are analyzed in order to determine the characteristics of the disk, hotspots, and white dwarfs. The UV continuum flux distributions are generally flatter than systems of low inclination and high mass-transfer rate, and the white dwarfs/inner disk appear to be relatively cool (15,000-19,000 K) for their orbital periods, possibly because the boundary layers are blocked from view. The continuum fluxes increase at spot phases, with the spot providing the dominant flux in IP Peg. The spot temperatures range from hot (20,000 K) in IP Peg, and perhaps in PG 1030+590, to cool (11,000 K) in V1315 Aql. The C IV emission lines show slightly larger decreases at spot phases than during eclipse, which implies an extended stream area.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sion, Edward M.; Sparks, Warren, E-mail: edward.sion@villanova.edu, E-mail: warrensparks@comcast.net
2014-11-20
The detection of heavy elements at suprasolar abundances in the atmospheres of some accreting white dwarfs in cataclysmic variables (CVs), coupled with the high temperatures needed to produce these elements, requires explosive thermonuclear burning. The central temperatures of any formerly more massive secondary stars in CVs undergoing hydrostatic CNO burning are far too low to produce these elements. Evidence is presented that at least some CVs contain donor secondaries that have been contaminated by white dwarf remnant burning during the common envelope phase and are transferring this material back to the white dwarf. This scenario does not exclude the channelmore » in which formerly more massive donor stars underwent CNO processing in systems with thermal timescale mass transfer. Implications for the progenitors of CVs are discussed and a new scenario for the white dwarf's accretion-nova-outburst is given.« less
Follow-up Observations of SDSS and CRTS Candidate Cataclysmic Variables II
NASA Astrophysics Data System (ADS)
Szkody, Paula; Everett, Mark E.; Dai, Zhibin; Serna-Grey, Donald
2018-01-01
Spectra of 38 candidate or known cataclysmic variables are presented. Most are candidate dwarf novae or systems containing possible highly magnetic white dwarfs, while a few (KR Aur, LS Peg, V380 Oph, and V694 Mon) are previously known objects caught in unusual states. Individual spectra are used to confirm a dwarf nova nature or other classification while radial velocities of 15 systems provide orbital periods and velocity amplitudes that aid in determining the nature of the objects. Our results substantiate a polar nature for four objects, find an eclipsing SW Sex star below the period gap, another as a likely intermediate polar, as well as two dwarf novae with periods in the middle of the gap. Based on observations obtained with the Apache Point Observatory (APO) 3.5 m telescope, which is owned and operated by the Astrophysical Research Consortium (ARC).
X ray spectra of cataclysmic variables
NASA Technical Reports Server (NTRS)
Patterson, Joseph; Halpern, Jules
1990-01-01
X ray spectral parameters of cataclysmic variables observed with the 'Einstein' imaging proportional counter were determined by fitting an optically thin, thermal bremsstrahlung spectrum to the raw data. Most of the sources show temperatures of order a few keV, while a few sources exhibit harder spectra with temperatures in excess of 10 keV. Estimated 0.1 to 3.5 keV luminosities are generally in the range from 10(exp 30) to 10(exp 32) erg/sec. The results are consistent with the x rays originating in a disk/white dwarf boundary layer of non-magnetic systems, or in a hot, post-shock region in the accretion column of DQ Her stars, with a negligible contribution from the corona of the companion. In a few objects column densities were found that are unusually high for interstellar material. It was suggested that the absorption occurs in the system itself.
Mass loss from interacting close binary systems
NASA Technical Reports Server (NTRS)
Plavec, M. J.
1981-01-01
The three well-defined classes of evolved binary systems that show evidence of present and/or past mass loss are the cataclysmic variables, the Algols, and Wolf-Rayet stars. It is thought that the transformation of supergiant binary systems into the very short-period cataclysmic variables must have been a complex process. The new evidence that has recently been obtained from the far ultraviolet spectra that a certain subclass of the Algols (the Serpentids) are undergoing fairly rapid evolution is discussed. It is thought probable that the remarkable mass outflow observed in them is connected with a strong wind powered by accretion. The origin of the circumbinary clouds or flat disks that probably surround many strongly interacting binaries is not clear. Attention is also given to binary systems with hot white dwarf or subdwarf components, such as the symbiotic objects and the BQ stars; it is noted that in them both components may be prone to an enhanced stellar wind.
High-velocity winds from a dwarf nova during outburst
NASA Technical Reports Server (NTRS)
Cordova, F. A.; Mason, K. O.
1982-01-01
An ultraviolet spectrum of the dwarf nova TW Vir during an optical outburst shows shortward-shifted absorption features with edge velocities as high as 4800 km/s, about the escape velocity of a white dwarf. A comparison of this spectrum with the UV spectra of other cataclysmic variables suggests that mass loss is evident only for systems with relatively high luminosities (more than about 10 solar luminosities) and low inclination angles with respect to the observer's line of sight. The mass loss rate for cataclysmic variables is of order 10 to the -11th solar mass per yr; this is from 0.01 to 0.001 of the mass accretion rate onto the compact star in the binary. The mass loss may occur by a mechanism similar to that invoked for early-type stars, i.e., radiation absorbed in the lines accelerates the accreting gas to the high velocities observed.
1ES 1113+432: Luminous, soft X-ray outburst from a nearby cataclysmic variable (AR Ursae Majoris)
NASA Technical Reports Server (NTRS)
Remillard, R. A.; Schachter, J. F.; Silber, A. D.; Slane, P.
1994-01-01
A remarkable X-ray transient from the Einstein Slew Survey, 1 ES 1113+432, is identified with a nearby, short-period cataclysmic variable. Wenzel (1993) has confirmed that the optical counterpart is the variable star, AR UMa (cataloged as 'semiregular'), erroneously reported 5.7 min southeast of the true position. One of the Einstein slew observations recorded a flux of 43 IPC counts/s, which is an order of magnitude above the flux observed from the brightest cataclysmic variables in other X-ray surveys. The outburst spectrum is extremely 'soft,' with an implied blackbody temperature of approximately 22 eV. The optical counterpart (V = 16.5) exhibits a strong UV component, TiO bands from an M star, and broadened Balmer emission lines. Optical states as bright as V approx. 13 were found on photographs from the Harvard Plate Library, confirming outburst behavior in the optical counterpart. The historical photographic record suggests that 1ES 1113+432 remains in a low-accretion state most of the time. Both of the soft X-ray spectrum and the transitions between high and low-accretion states are suggestive of the AM Her (magnetic) subclass. Photometric observations in the I band show 0.18 mag modulations at a period of 0.966 hr. These are interpreted as ellipsiodal variations in the secondary star for a binary period of 1.932 hr, which is near the lower boundary of the 'period gap' in the histogram, of orbital periods of accreting white dwarfs. Thus 1ES 1113+432 provides the rare opportunity to study a secondary star in a cataclysmic binary that has evolved through the period gap. The optical spectral features from the secondary imply a spectral type of approximately M6 and a distance of approximately 88 pc. The peak luminosity in the soft X-ray component (unabsorbed) is then estimated to be 3 X 10(exp 33) ergs/s, assuming emission from a blackbody slab with a temperature of 22 eV. While this luminosity is higher than previous measures of the soft X-ray component, it does not exceed the amount of radiation that could be emitted from the accretion-heated surface of a white dwarf.
Couch kids: correlates of television viewing among youth.
Gorely, Trish; Marshall, Simon J; Biddle, Stuart J H
2004-01-01
The purpose of this study was to review the published empirical correlates of television/video viewing among youth (2 to 18 years). A descriptive semi-quantitative review was conducted based on 68 primary studies. Variables consistently associated with TV/video viewing were ethnicity (non-white +), parent income (-), parent education (-), body weight (+), between meal snacking (+), number of parents in the house (-), parents TV viewing habits (+), weekend (+) and having a TV in the bedroom (+). Variables consistently unrelated to TV/video viewing were sex, other indicators of socio-economic status, body fatness, cholesterol levels, aerobic fitness, strength, other indicators of fitness, self-perceptions, emotional support, physical activity, other diet variables, and being an only child. Few modifiable correlates have been identified. Further research should aim to identify modifiable correlates of TV/video viewing if interventions are to be successfully tailored to reduce this aspect of inactivity among youth.
ERIC Educational Resources Information Center
Chevallier, Eric; Mansour, Sylvie
1993-01-01
This booklet examines the influence of television on children and adolescents in developing and developed nations, reviewing research on television's relationship to child health and development. The first section reviews specific research on such variables as number of television sets in use, amount of time spent watching television, age, sex,…
NSV 1907 - A new eclipsing, nova-like cataclysmic variable
NASA Astrophysics Data System (ADS)
Hümmerich, Stefan; Gröbel, Rainer; Hambsch, Franz-Josef; Dubois, Franky; Ashley, Richard; Gänsicke, Boris T.; Vanaverbeke, Siegfried; Bernhard, Klaus; Wils, Patrick
2017-01-01
NSV 1907, formerly listed as an irregular variable in variability catalogues, was classified as an Algol-type eclipsing binary in the Catalina Surveys Periodic Variable Star Catalogue. We have identified NSV 1907 as an ultraviolet (UV) bright source using measurements from the GALEX space telescope and detected obvious out-of-eclipse variability in archival photometric data from the Catalina Sky Survey, which instigated a closer examination of the object. A spectrum and extensive multicolour photometric observations were acquired, from which we deduce that NSV 1907 is a deeply eclipsing, nova-like cataclysmic variable. Apart from the orbital variations (deep eclipses with a period of P ≈ 6.63 hours), changes in mean brightness and irregular short-term variability (flickering) were observed. The presence of a secondary minimum at phase φ ≈ 0.5 was established, which indicates a significant contribution of the companion star to the optical flux of the system. We find possible evidence for sinusoidal variations with a period of P ≈ 4.2 d, which we interpret as the nodal precession period of the accretion disc. No outbursts or VY Scl-like drops in brightness were detected either by the CSS or during our photometric monitoring. Because of its spectral characteristics and the observed variability pattern, we propose NSV 1907 as a new moderately bright long-period SW Sextantis star. Further photometric and spectroscopic observations are encouraged.
Models for various aspects of dwarf novae and nova-like stars
NASA Technical Reports Server (NTRS)
Ladous, Constanze
1993-01-01
The first attempts to explain the nature of dwarf novae were based on the assumption of single-star phenomena, in which emission lines were assumed to be caused by circumstellar gas shells. The outburst behavior was tentatively ascribed to the kind of (also not understood) mechanism leading to nova outbursts. The realization that some, and possibly all, dwarf novae and nova-like stars (and novae) are binaries eventually led to models which bore more and more similarities to the modern interpretation on the basis of the Roche model. Not all cataclysmic variables are known binaries. In fact, with respect to the entire number of known objects, the proven binaries are still the minority, but all the brightest variables are in fact known to binaries. Not a single system is known which exhibits the usual characteristics of a cataclysmic variable and at the same time can be declared with certainty to be a single star. Two systems are known, the dwarf nova EY Cyg and the recurrent nova V1017 Sgr, in which, in spite of intensive search, no radial velocity variations have been found; but they still exhibit composite spectra consisting of a bright continuum, an emission spectrum, and a cool absorption spectrum. If the Roche model is correct, it is to be expected that a small percentage of objects is viewed pole-on, so orbital motions do not make themselves felt as Doppler shifts of spectral lines. So even these two systems support the hypothesis that all cataclysmic variables (with the possible exception of symbiotic stars) are binaries. In cataclysmic variables, it seems that the brightness changes observed in dwarf novae and nova-like stars in the optical and the UV are due directly to changes in the accretion disks. The study and understanding of accretion disks in these systems can bear potentially valuable consequences for many other fields in astronomy. The observed spectra of dwarf novae and nova-like stars comprise a fairly large range: pure emission spectra, pure absorption spectra, a mixture of both, asymmetric line profiles, very different slopes of the continuous flux distribution -- and one single system may exhibit all of these features at different times. Agreement and disagreement between computed and observed spectra should show whether or not the Roche model is applicable and where it probably will have to be modified and improved. Except for their outburst behavior and its immediate consequences, novae, dwarf novae, and nova-like stars cannot be physically distinguished from each other.
Discovery of a New Classical Nova Shell Around a Nova-like Cataclysmic Variable
NASA Astrophysics Data System (ADS)
Guerrero, Martín A.; Sabin, Laurence; Tovmassian, Gagik; Santamaría, Edgar; Michel, Raul; Ramos-Larios, Gerardo; Alarie, Alexandre; Morisset, Christophe; Bermúdez Bustamante, Luis C.; González, Chantal P.; Wright, Nicholas J.
2018-04-01
The morphology and optical spectrum of IPHASX J210204.7+471015, a nebula classified as a possible planetary nebula are, however, strikingly similar to those of AT Cnc, a classical nova shell around a dwarf nova. To investigate its true nature, we have obtained high-resolution narrowband [O III] and [N II] images and deep optical spectra. The nebula shows an arc of [N II]-bright knots notably enriched in nitrogen, while an [O III]-bright bow shock is progressing throughout the ISM. Diagnostic line ratios indicate that shocks are associated with the arc and bow shock. The central star of this nebula has been identified by its photometric variability. Time-resolved photometric and spectroscopic data of this source reveal a period of 4.26 hr, which is attributed to a binary system. The optical spectrum is notably similar to that of RW Sex, a cataclysmic variable star (CV) of the UX UMa nova-like (NL) type. Based on these results, we propose that IPHASX J210204.7 + 471015 is a classical nova shell observed around a CV-NL system in quiescence.
An Hα-selected sample of cataclysmic variables - I. Observations of newly discovered systems
NASA Astrophysics Data System (ADS)
Pretorius, Magaretha L.; Knigge, Christian
2008-04-01
Strong selection effects are present in observational samples of cataclysmic variables (CVs), complicating comparisons to theoretical predictions. The selection criteria used to define most CV samples discriminate heavily against the discovery of short-period, intrinsically faint systems. The situation can be improved by selecting CVs for the presence of emission lines. For this reason, we have constructed a homogeneous sample of CVs selected on the basis of Hα emission. We present discovery observations of the 14 CVs and two additional CV candidates found in this search. The orbital periods of 11 of the new CVs were measured; all are above 3 h. There are two eclipsing systems in the sample, and one in which we observed a quasi-periodic modulation on a ~1000s time-scale. We also detect the secondary star in the spectrum of one system, and measure its spectral type. Several of the new CVs have the spectroscopic appearance of nova-like variables, and a few display what may be SW Sex star behaviour. In a companion paper, we discuss the implications of this new sample for CV evolution.
Observations of GAIA-identified Cataclysmic Variables Using the TUBITAK National Observatory
NASA Astrophysics Data System (ADS)
Esenoglu, Hasan H.; Kirbiyik, Halil; Kaynar, Suleyman; Okuyan, Oguzhan; Hamitoglu, Irek; Galeev, Almaz; Uluc, Kadir; Kocak, Murat; Kilic, Sila E.; Parmaksizoglu, Murat; Erece, Orhan; Ozisik, Tuncay; Gulsecen, Hulusi
2016-07-01
TUBITAK National Observatory supports the GAIA alerts with observations using three telescopes (RTT150, T100, T60) at the site with a limited time quota. We have observed 10 variable stars among GAIA sources discovered in the years 2014-2016 that may be candidate Cataclysmic Variables (CVs). Our TUG observations at this stage involve photometry and spectroscopy to aid the identification of these sources. The first preliminary result of our observations of Gaia14aat among them showed a dwarf nova outburst with an amplitude of 2.69 mag. We aim to construct a GAIA astrophysics group to study CVs along with supported studies using the SRG (Spectrum Roentgen Gamma astrophysical observatory) after the year of 2016. These observations will basically involve spectroscopy, narrow-band CCD imaging and photometry using several filters to aid the identification of these sources. RTT150 observations with very narrow filters (like H-alpha, SII, OIII with band width of range of 2 to 5 nm) will reveal whether shell around the SRG sources to aid identification novae among them.
Attention to and Memory for Audio and Video Information in Television Scenes.
ERIC Educational Resources Information Center
Basil, Michael D.
A study investigated whether selective attention to a particular television modality resulted in different levels of attention to and memory for each modality. Two independent variables manipulated selective attention. These were the semantic channel (audio or video) and viewers' instructed focus (audio or video). These variables were fully…
Sound Effects for Children's Comprehension of Variably-Paced Television Programs.
ERIC Educational Resources Information Center
Calvert, Sandra L.; Scott, M. Catherine
In this study, children's selective attention to, and comprehension of, variably-paced television programs were examined as a function of sound effects. Sixty-four children, equally distributed by sex and by preschool and fourth grades, were randomly assigned to one of four treatment conditions which crossed two levels of sound effects (presence…
Exploratory Spectroscopy of Magnetic Cataclysmic Variables Candidates and Other Variable Objects
DOE Office of Scientific and Technical Information (OSTI.GOV)
Oliveira, A. S.; Palhares, M. S.; Rodrigues, C. V.
2017-04-01
The increasing number of synoptic surveys made by small robotic telescopes, such as the photometric Catalina Real-Time Transient Survey (CRTS), provides a unique opportunity to discover variable sources and improves the statistical samples of such classes of objects. Our goal is the discovery of magnetic Cataclysmic Variables (mCVs). These are rare objects that probe interesting accretion scenarios controlled by the white-dwarf magnetic field. In particular, improved statistics of mCVs would help to address open questions on their formation and evolution. We performed an optical spectroscopy survey to search for signatures of magnetic accretion in 45 variable objects selected mostly from themore » CRTS. In this sample, we found 32 CVs, 22 being mCV candidates, 13 of which were previously unreported as such. If the proposed classifications are confirmed, it would represent an increase of 4% in the number of known polars and 12% in the number of known IPs. A fraction of our initial sample was classified as extragalactic sources or other types of variable stars by the inspection of the identification spectra. Despite the inherent complexity in identifying a source as an mCV, variability-based selection, followed by spectroscopic snapshot observations, has proved to be an efficient strategy for their discoveries, being a relatively inexpensive approach in terms of telescope time.« less
Television Violence and Behavior: A Research Summary. ERIC Digest.
ERIC Educational Resources Information Center
Smith, Marilyn E.
This digest describes the overall pattern of the results of research on television violence and behavior. Several variables in the relationship between television violence and aggression related to characteristics of the viewers and to the portrayal of violence are identified. Viewer characteristics included: age, amount of television watched,…
Doing Televised Rhetorical Analysis as a Means of Promoting College Awareness in a Target Market.
ERIC Educational Resources Information Center
Schnell, Jim
This paper describes aspects of doing televised rhetorical analysis as they relate to the promotion of college awareness in a particular target market. Considerations in the paper include variables that most professors encounter in their efforts to address the "service" expectations of their employment and how these variables can be…
TV watching, soap opera and happiness.
Lu, L; Argyle, M
1993-09-01
One hundred and fourteen subjects reported the amount of time they spent watching television in general, and soap opera in particular. They also completed scales measuring happiness and other personality variables, such as extraversion and cooperativeness. In the multiple regression analysis, having controlled for the demographic variables, watching TV was related to unhappiness, whereas watching soap opera was related to happiness. Discriminant analysis showed that females, higher happiness and extraversion distinguished regular soap watchers (who nevertheless watched little TV in general) from irregular soap watchers (who nevertheless watched a lot of TV in general).
KR Aur - extremely high variations in optical bands
NASA Astrophysics Data System (ADS)
Boeva, S.; Latev, G.; Nikolov, Y.; Nikolov, P.; Nikolov, G.; Spassov, B.; Petrov, B.; Damljanovic, G.; Sekulic, M.; Zamanov, R.
2017-03-01
Since 2008, the cataclysmic variable star KR Aur is in deep minimum state with a short brightening in 2010. We performed photometric monitoring in 12 nights during the period August 2016 - February 2017 with the telescopes of Rozhen (Bulgaria), Belogradchik (Bulgaria) and Vidojevica (Serbia).
Irradiation and Enhanced Magnetic Braking in Cataclysmic Variables
NASA Astrophysics Data System (ADS)
McCormick, P. J.; Frank, J.
1998-12-01
In previous work we have shown that irradiation driven mass transfer cycles can occur in cataclysmic variables at all orbital periods if an additional angular momentum loss mechanism is assumed. Earlier models simply postulated that the enhanced angular momentum loss was proportional to the mass transfer rate without any specific physical model. In this paper we present a simple modification of magnetic braking which seems to have the right properties to sustain irradiation driven cycles at all orbital periods. We assume that the wind mass loss from the irradiated companion consists of two parts: an intrinsic stellar wind term plus an enhancement that is proportional to the irradiation. The increase in mass flow reduces the specific angular momentum carried away by the flow but nevertheless yields an enhanced rate of magnetic braking. The secular evolution of the binary is then computed numerically with a suitably modified double polytropic code (McCormick & Frank 1998). With the above model and under certain conditions, mass transfer oscillations occur at all orbital periods.
NASA Astrophysics Data System (ADS)
Howell, Steve B.; Cash, Jennifer; Mason, Keith O.; Herzog, Adrienne E.
1999-02-01
We present the first UV spectral observations of six magnetic cataclysmic variables discovered by the ROSAT Wide Field Camera (WFC). Using the^ International Ultraviolet Explorer (IUE), 1200-3400 Å spectra were obtained of the AM Herculis stars RE 0531-46, RE 1149+28, RE 1844-74, QS Tel (RE 1938-46), and HU Aqr (RE 2107-05) and the DQ Herculis star PQ Gem (RE 0751+14). The high-state UV spectra are dominated by strong emission lines. Continuum flux distributions for these stars (from 100 to 5500 Å) reveal that over this entire range, none of the spectral energy distributions can be fitted by a single-valued blackbody. Our new UV observations and additional archival IUE spectra were used to discover a correlation between the strength of the high-state UV emission lines and the strength of the white dwarf magnetic field. Model spectral results are used to confirm the production of the UV emission lines by photoionization from X-ray and EUV photons.
The primary role of the SW Sextantis stars in the evolution of cataclysmic variables
NASA Astrophysics Data System (ADS)
Torres, Manuel; Gaensicke, Boris; Rodriguez-Gil, Pablo; Long, Knox; Marsh, Tom; Steeghs, Danny; Munoz-Darias, Teodoro; Shahbaz, Tariq; Schmidtobreick, Linda; Schreiber, Matthias
2009-02-01
SW Sextantis stars are a relatively large group of cataclysmic variables (CVs) which plays a fundamental role in our understanding of CV structure and evolution. Very little is known about the properties of their accreting white dwarfs and their donor stars, as the stellar components are usually outshone by an extremely bright accretion flow. Consequently, a proper assesment of their evolutionary state is illusionary. We are monitoring the brightness of a number of SW Sex stars and request here Gemini/GMOS-N ToO time to obtain orbital phase-resolved spectroscopy if one of them enters a low state, since this is the only opportunity for studying the stellar components individually. These data will be used to accurately measure the binary parameters, white dwarf temperature, and distance to the system for a SW Sex star for the first time. The measured stellar masses and radii will especially be a precious input to the theory of compact binary evolution as a whole.
Unravelling the role of the SW Sextantis stars in the evolution of cataclysmic variables
NASA Astrophysics Data System (ADS)
Torres, Manuel; Steeghs, Danny; Gaensicke, Boris; Marsh, Tom; Rodriguez-Gil, Pablo; Schmidtobreick, Linda; Long, Knox; Schreiber, Matthias
2007-08-01
SW Sextantis stars are a relatively large group of cataclysmic variables (CVs) whose properties contradict all predictions made by the current CV evolution theories. Very little is known about the properties of their accreting white dwarfs and their donor stars, as the stellar components are usually outshone by an extremely bright accretion flow. Consequently, a proper assesment of their evolutionary state is illusionary. We are monitoring the brightness of a number of SW Sex stars and request here Gemini/GMOS-N ToO time to obtain orbital phase-resolved spectroscopy if one of them enters a low state, since this is the only opportunity for studying the stellar components individually. These data will be used to accurately measure the mass ratio of the system which, combined with the orbital inclination derived from modelling of either the disc eclipses in the high state or the ellipsoidal modulation in the low state, will eventually provide the first detailed system parameters for any SW Sex star.
Unravelling the role of the SW Sextantis stars in the evolution of cataclysmic variables
NASA Astrophysics Data System (ADS)
Torres, Manuel
2007-02-01
SW Sextantis stars are a relatively large group of cataclysmic variables (CVs) whose properties contradict all predictions made by the current CV evolution theories. Very little is known about the properties of their accreting white dwarfs and their donor stars, as the stellar components are usually outshone by an extremely bright accretion flow. Consequently, a proper assesment of their evolutionary state is illusionary. We are monitoring the brightness of a number of SW Sex stars and request here Gemini/GMOS-N ToO time to obtain orbital phase-resolved spectroscopy if one of them enters a low state, since this is the only opportunity for studying the stellar components individually. These data will be used to accurately measure the mass ratio of the system which, combined with the orbital inclination derived from modelling of either the disc eclipses in the high state or the ellipsoidal modulation in the low state, will eventually provide the first detailed system parameters for any SW Sex star.
On the orbital period of the magnetic cataclysmic variable HU Aquarii
NASA Astrophysics Data System (ADS)
Vogel, J.; Schwope, A.; Schwarz, R.; Kanbach, G.; Dhillon, V. S.; Marsh, T. R.
2008-02-01
We present an analysis of ULTRACAM light curves of the magnetic cataclysmic variable HU Aquarii which were taken at the VLT in May 2005. Since the light curves were serendipitously obtained during a low state, they allowed us to determine the binary and the stellar parameters with high accuracy. The light curve was decomposed into the components originating from the accretion spot, the photosphere surrounding it and the white dwarf itself, which allowed us to extract the eclipse light curve for the pure white dwarf. Combined with high-time resolution observations with different instruments over a 12 year baseline it was possible to get exact eclipse timings of the white dwarf and thus establish a significant deviation from a linear ephemeris. If described by a quadratic term, the period decreases by -1.13×10-11 ss-1. Interpreting this change in period as a pure angular momentum loss (AML) effect, the rate of J˙ = -4.9×1035 erg is much too high to be explained by gravitational radiation alone.
NASA Astrophysics Data System (ADS)
Belloni, Diogo; Schreiber, Matthias R.; Zorotovic, Mónica; Iłkiewicz, Krystian; Hurley, Jarrod R.; Giersz, Mirek; Lagos, Felipe
2018-06-01
The predicted and observed space density of cataclysmic variables (CVs) have been for a long time discrepant by at least an order of magnitude. The standard model of CV evolution predicts that the vast majority of CVs should be period bouncers, whose space density has been recently measured to be ρ ≲ 2 × 10-5 pc-3. We performed population synthesis of CVs using an updated version of the Binary Stellar Evolution (BSE) code for single and binary star evolution. We find that the recently suggested empirical prescription of consequential angular momentum loss (CAML) brings into agreement predicted and observed space densities of CVs and period bouncers. To progress with our understanding of CV evolution it is crucial to understand the physical mechanism behind empirical CAML. Our changes to the BSE code are also provided in details, which will allow the community to accurately model mass transfer in interacting binaries in which degenerate objects accrete from low-mass main-sequence donor stars.
SPECTROSCOPIC ORBITAL PERIODS FOR 29 CATACLYSMIC VARIABLES FROM THE SLOAN DIGITAL SKY SURVEY
DOE Office of Scientific and Technical Information (OSTI.GOV)
Thorstensen, John R.; Taylor, Cynthia J.; Peters, Christopher S.
2015-04-15
We report follow-up spectroscopy of 29 cataclysmic variables from the Sloan Digital Sky Survey (SDSS), 22 of which were discovered by SDSS and seven of which are previously known systems that were recovered in SDSS. The periods for 16 of these objects were included in the tabulation by Gänsicke et al. While most of the systems have periods less than 2 hr, only one has a period in the 80–86 minutes “spike” found by Gänsicke et al., and 11 have periods longer than 3 hr, indicating that the present sample is skewed toward longer-period, higher-luminosity objects. Seven of the objectsmore » have spectra resembling dwarf novae, but have apparently never been observed in outburst, suggesting that many cataclysmics with relatively low variability amplitude remain to be discovered. Some of the objects are notable. SDSS J07568+0858 and SDSS J08129+1911 were previously known to have deep eclipses; in addition to spectroscopy, we use archival data from the Catalina Real Time Transient Survey to refine their periods. We give a parallax-based distance of 195 (+54, −39) pc for LV Cnc (SDSS J09197+0857), which at P{sub orb} = 81 m has the shortest orbital period in our sample. SDSS J08091+3814 shows both the spectroscopic phase offset and phase-dependent absorption found in SW Sextantis stars. The average spectra of SDSS J08055+0720 and SDSS J16191+1351 show contributions from K-type secondaries, and SDSS J080440+0239 shows a contribution from an early M star. We use these to constrain the distances. SDSS J09459+2922 has characteristics typical of a magnetic system. SDSS11324+6249 may be a novalike variable, and if so, its orbital period (99 minutes) is unusually short for that subclass.« less
de Souza, Sara Carolina Scremin; Campanini, Marcela Zambrim; de Andrade, Selma Maffei; González, Alberto Durán; de Melo, Juliana Moura; Mesas, Arthur Eumann
2017-10-01
Although time spent watching television and sleep problems have increased in the last few decades, it is unclear whether these conditions are associated in working adults after controlling for lifestyle, job characteristics and other individual aspects. The present study analyzed the association between time spent watching television and sleep quality among teachers from public schools in Londrina, Brazil. In this cross-sectional study, information from the Pittsburgh Sleep Quality Index (PSQI) and about time spent watching television was obtained during personal interviews. Logistic regression models adjusted by the main confounders (sociodemographic, occupational and lifestyle variables) were used in the analyses. Among the 959 studied teachers (68.2% women, median age: 42years), teachers who watched >120min/day had a higher likelihood of reporting poor sleep quality (PSQI>5) (odds ratio=1.41; 95% confidence interval=1.01; 1.98) compared with those who watched television for up to 60min/day, regardless of gender, age, work hours, leisure time physical activity and other lifestyle variables. This association did not remain significant after the adjustment for health conditions, i.e., obesity, anxiety, depression and chronic pain, which may act as confounding variables in the relationship between watching television and poor sleep quality. Watching television for >120min/day was independently associated with poorer sleep quality, which should be considered in the prevention and treatment of sleep disturbances among working population. Copyright © 2017 Elsevier Inc. All rights reserved.
2MASS J22560844+5954299: the newly discovered cataclysmic star with the deepest eclipse
NASA Astrophysics Data System (ADS)
Kjurkchieva, D.; Khruzina, T.; Dimitrov, D.; Groebel, R.; Ibryamov, S.; Nikolov, G.
2015-12-01
Context. The SW Sex stars are assumed to represent a distinguished stage in cataclysmic variable (CV) evolution, making it especially important to study them. Aims: We discovered a new cataclysmic star and carried out prolonged and precise photometric observations, as well as medium-resolution spectral observations. Modelling these data allowed us to determine the physical parameters and to establish its peculiarities. Methods: To obtain a light curve solution we used model whose emission sources are a white dwarf surrounded by an accretion disk with a hot spot, a gaseous stream near the disk's lateral side, and a secondary star filling its Roche lobe. The obtained physical parameters are compared with those of other SW Sex-subtype stars. Results: The newly discovered cataclysmic variable 2MASS J22560844+5954299 shows the deepest eclipse amongst the known nova-like stars. It was reproduced by totally covering a very luminous accretion disk by a red secondary component. The temperature distribution of the disk is flatter than that of steady-state disk. The target is unusual with the combination of a low mass ratio q ~ 1.0 (considerably below the limit q = 1.2 of stable mass transfer of CVs) and an M-star secondary. The intensity of the observed three emission lines, Hα, He 5875, and He 6678, sharply increases around phase 0.0, accompanied by a Doppler jump to the shorter wavelength. The absence of eclipses of the emission lines and their single-peaked profiles means that they originate mainly in a vertically extended hot-spot halo. The emission Hα line reveals S-wave wavelength shifts with semi-amplitude of around 210 km s-1 and phase lag of 0.03. Conclusions: The non-steady-state emission of the luminous accretion disk of 2MASS J22560844+5954299 was attributed to the low viscosity of the disk matter caused by its unusually high temperature. The star shows all spectral properties of an SW Sex variable apart from the 0.5 central absorption. Based on data collected with the telescopes at Rozhen National Astronomical Observatory.Spectra (FITS files) are 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/584/A40
Variable word length encoder reduces TV bandwith requirements
NASA Technical Reports Server (NTRS)
Sivertson, W. E., Jr.
1965-01-01
Adaptive variable resolution encoding technique provides an adaptive compression pseudo-random noise signal processor for reducing television bandwidth requirements. Complementary processors are required in both the transmitting and receiving systems. The pretransmission processor is analog-to-digital, while the postreception processor is digital-to-analog.
X-ray Variability of the Magnetic Cataclysmic Variable V1432 Aql and the Seyfert Galaxy NGC 6814
NASA Technical Reports Server (NTRS)
Mukai, K.; Hellier, C.; Madejski, G.; Patterson, J.; Skillman, D. R.
2003-01-01
V1432 Aquilae (=RX J1940.2-1025) is the X-ray bright, eclipsing magnetic cataclysmic variable approximately 37 (sup) away from the Seyfert galaxy, NGC 6814. Due to a 0.3% difference between the orbital (12116.3 s) and the spin (12150 s) periods: the accretion geometry changes over the approximately 50 day beat period. Here we report the results of an RXTE campaign to observe the eclipse 25 times, as well as of archival observations with ASCA and BeppoSAX. Having confirmed that the eclipse is indeed caused by the secondary, we use the eclipse timings and profiles to map the accretion geometry as a function of the beat phase. We find that the accretion region is compact, and that it moves relative to the center of white dwarf on the beat period. The amplitude of this movement suggest a low-mass white dwarf, in contrast to the high mass previously estimated from its X-ray spectrum. The size of the X-ray emission region appears to be larger than in other eclipsing magnetic CVs. We also report on the RXTE data as well as the long-term behavior of NGC 6814, indicating flux variability by a factor of at least 10 on time scales of years.
Verloigne, Maïté; Van Lippevelde, Wendy; Bere, Elling; Manios, Yannis; Kovács, Éva; Grillenberger, Monika; Maes, Lea; Brug, Johannes; De Bourdeaudhuij, Ilse
2015-09-18
The aim was to investigate which individual and family environmental factors are related to television and computer time separately in 10- to-12-year-old children within and across five European countries (Belgium, Germany, Greece, Hungary, Norway). Data were used from the ENERGY-project. Children and one of their parents completed a questionnaire, including questions on screen time behaviours and related individual and family environmental factors. Family environmental factors included social, political, economic and physical environmental factors. Complete data were obtained from 2022 child-parent dyads (53.8 % girls, mean child age 11.2 ± 0.8 years; mean parental age 40.5 ± 5.1 years). To examine the association between individual and family environmental factors (i.e. independent variables) and television/computer time (i.e. dependent variables) in each country, multilevel regression analyses were performed using MLwiN 2.22, adjusting for children's sex and age. In all countries, children reported more television and/or computer time, if children and their parents thought that the maximum recommended level for watching television and/or using the computer was higher and if children had a higher preference for television watching and/or computer use and a lower self-efficacy to control television watching and/or computer use. Most physical and economic environmental variables were not significantly associated with television or computer time. Slightly more individual factors were related to children's computer time and more parental social environmental factors to children's television time. We also found different correlates across countries: parental co-participation in television watching was significantly positively associated with children's television time in all countries, except for Greece. A higher level of parental television and computer time was only associated with a higher level of children's television and computer time in Hungary. Having rules regarding children's television time was related to less television time in all countries, except for Belgium and Norway. Most evidence was found for an association between screen time and individual and parental social environmental factors, which means that future interventions aiming to reduce screen time should focus on children's individual beliefs and habits as well parental social factors. As we identified some different correlates for television and computer time and across countries, cross-European interventions could make small adaptations per specific screen time activity and lay different emphases per country.
Yoo, Jina H; Tian, Yan
2011-03-01
This study investigates antecedents and outcomes of entertainment television consumption in organ donation with the Orientation₁-Stimulus-Orientation₂-Response (O₁-S-O₂ -R) model. It reveals that organ donation knowledge seems significantly related to recall of entertainment television programs and attitudes toward organ donation. Meanwhile, recall of entertainment television programs significantly predicts people's perception of medical mistrust, which in turn negatively predicts attitudes toward organ donation, while attitudes toward organ donation significantly predict behavioral intention in signing a donor card. It also suggests significant mediation relationships among the pre-orientation variable, stimulus, post-orientation variable, and attitudinal and behavioral outcomes. This study provides an integrative theoretical framework to study media effects on organ donation and empirical evidence for "entertainment miseducation" (Morgan, Harrison, Chewning, Davis, & DiCorcia, 2007).
The Effects of Market Structure on Television News Pricing.
ERIC Educational Resources Information Center
Wirth, Michael O.; Wollert, James A.
Multiple regression techniques were used to examine the business side of local television news operations for November 1978. Research questions examined the effect of several variables on local television news prices (advertising rates), including type of ownership, network affiliation/signal type, market size, cable network penetration, market…
Association between family variables and Mexican American children's dietary behaviors.
Ayala, Guadalupe X; Baquero, Barbara; Arredondo, Elva M; Campbell, Nadia; Larios, Sandra; Elder, John P
2007-01-01
To examine the association between family variables and children's diets. Cross-sectional study with households sampled using random-digit dialing. Children completed a one-time, self-administered survey, and mothers participated in a face-to-face structured interview. Data collection occurred in southern San Diego County on the U.S.-Mexico border. One hundred sixty-seven Mexican American children between 8 and 18 years of age and their mothers. Diet: number of snacks, candies and sweets, and sodas consumed daily; dietary fat and fiber; and money spent weekly on fast food and snacks. Family variables: household size, family support for healthful eating, number of meals eaten together, availability of fast food in the home, food ads seen on television, and parent purchasing food products that children saw advertised on television. Regression analyses were used to examine the independent contributions of family variables on dietary intake. Statistical significance was set at P < .05. Greater family support for healthful eating was associated with fewer snacks and more fiber consumed. Children of parents who purchased food products that their children had seen advertised on television reported consuming more snacks and more fat, and they spent more money on fast food and snacks. Family-based interventions are needed to moderate the potential influence of television-advertised food products on children's requests for these food products.
Fogel, Joshua; Shlivko, Alexander
2016-01-02
Reality television watching and social media use are popular activities. Reality television can include mention of illegal drug use and prescription drug misuse. To determine if reality television and social media use of Twitter are associated with either illegal drug use or prescription drug misuse. Survey of 576 college students in 2011. Independent variables included watching reality television (social cognitive theory), parasocial interaction (parasocial interaction theory), television hours watched (cultivation theory), following a reality television character on Twitter, and demographics. Outcome variables were illegal drug use and prescription drug misuse. Watching reality television and also identifying with reality TV program characters were each associated with greater odds for illegal drug use. Also, following a reality TV character on Twitter had greater odds for illegal drug use and also in one analytical model for prescription drug misuse. No support was seen for cultivation theory. Those born in the United States had greater odds for illegal drug use and prescription drug misuse. Women and Asians had lower odds for illegal drug use. African Americans and Asians had lower odds for prescription drug misuse. Physicians, psychologists, and other healthcare practitioners may find it useful to include questions in their clinical interview about reality television watching and Twitter use. Physician and psychology groups, public health practitioners, and government health agencies should consider discussing with television broadcasting companies the potential negative impact of including content with illegal drugs and prescription drug misuse on reality television programs.
Children's Television Viewing as Affected by Contextual Variables in the Home.
ERIC Educational Resources Information Center
Webster, Debra Burns; And Others.
A study was conducted to explore the relationship between a mother working outside the home and the amount of television a child views. It was hypothesized that the hours of television viewed by a child would be positively related to the amount of television viewed by (1) the female head of household, (2) the male head of household, (3) the number…
ERIC Educational Resources Information Center
Beisenherz, Paul Chalmers
The effectiveness of a televised science series used in the Seattle metropolitan area was investigated, using factorial design to provide a treatment variable representing four degrees of utilization of TV science and non-TV science. Teachers and their intact classes were randomly assigned to one of four treatment groups: TV science only, plus…
Televised Violence and Related Variables as Predictors of Self-Reported Verbal Aggression.
ERIC Educational Resources Information Center
Whaley, A. Bennett
1982-01-01
Results of this study indicate that no relationship was found between the respondents' verbal aggression and their viewing of either physical or verbal violence on television; no association was found between their aggressive predisposition and television viewing habits; and no association was found between their gender and preference for violent…
The Perceived Reality of Television and Aggressive Predispositions Among Children in Mexico.
ERIC Educational Resources Information Center
Korzenny, Felipe
The purpose of this study was to assess the effectiveness of several independent variables in predicting the perception of television's content as real. The relationship between the perception of television violence as real and agressive predispositions of young viewers was analyzed. Two hundred seventy-three Mexican children in the third and…
Empirical Studies on Television Composition.
ERIC Educational Resources Information Center
Metallinos, Nikos
A review of research on television's major compositional factors was undertaken to determine the status of such research and to note the major variables involved in the structure of television pictures. It was found that such research could be grouped in four categories--lighting and color, staging, editing, and sound--and that these areas covered…
Externalizing behaviors and television viewing in children of low-income minority parents.
Gupta, V B; Nwosa, N M; Nadel, T A; Inamdar, S
2001-06-01
The parents of 151 children, ages 4-16 years, attending the pediatric outpatient clinic of an urban hospital were surveyed to determine if aggressive behavior among children of low literacy and low-income parents is related to excessive television viewing or to sociological variables such as ethnicity/race, education, occupation, and parents' marital status. The survey consisted of 22 questions about the ethnicity, marital status, education, and occupation of the parent, the television viewing behavior of the child, and the externalizing behavior scale of the Child Behavior Checklist of Achenbach (CBC). The television viewing habits of children in this study were not significantly different from viewing habits reported in national surveys of the US population. T scores in the aggression scale of CBC were unrelated to the hours of television watched by children and the control of viewing by the parent but were significantly associated with the employment and marital status of the mother. Children of unemployed and single mothers had higher externalizing-behavior scores, suggesting that family ecological variables may have more influence on children's behavior than the duration of television viewing.
A multichannel fiber optic photometer present performance and future developments
NASA Technical Reports Server (NTRS)
Barwig, H.; Schoembs, R.; Huber, G.
1988-01-01
A three channel photometer for simultaneous multicolor observations was designed with the aim of making possible highly efficient photometry of fast variable objects like cataclysmic variables. Experiences with this instrument over a period of three years are presented. Aspects of the special techniques applied are discussed with respect to high precision photometry. In particular, the use of fiber optics is critically analyzed. Finally, the development of a new photometer concept is discussed.
Messages about Education in TV Programs Popular with Children and Teenagers. Final Report.
ERIC Educational Resources Information Center
Williams, Tannis MacBeth; And Others
Televised portrayals of variables that are related to educational and occupational aspirations and educational motivation have the potential to influence viewers' attitudes, expectations, and behaviors in these domains. In order to test this premise, a study assessed messages about these variables and about drug use in the prime-time television…
Jucker, Jean-Luc; Thornborrow, Tracey; Beierholm, Ulrik; Burt, D Michael; Barton, Robert A; Evans, Elizabeth H; Jamieson, Mark A; Tovée, Martin J; Boothroyd, Lynda G
2017-08-16
Television consumption influences perceptions of attractive female body size. However, cross-cultural research examining media influence on body ideals is typically confounded by differences in the availability of reliable and diverse foodstuffs. 112 participants were recruited from 3 Nicaraguan villages that differed in television consumption and nutritional status, such that the contribution of both factors could be revealed. Participants completed a female figure preference task, reported their television consumption, and responded to several measures assessing nutritional status. Communities with higher television consumption and/or higher nutritional status preferred thinner female bodies than communities with lower television consumption and/or lower nutritional status. Bayesian mixed models estimated the plausible range of effects for television consumption, nutritional status, and other relevant variables on individual preferences. The model explained all meaningful differences between our low-nutrition villages, and television consumption, after sex, was the most likely of these predictors to contribute to variation in preferences (probability mass >95% when modelling only variables with zero-order associations with preferences, but only 90% when modelling all possible predictors). In contrast, we found no likely link with nutritional status. We thus found evidence that where media access and nutritional status are confounded, media is the more likely predictor of body ideals.
Evolution of magnetic cataclysmic binaries
NASA Technical Reports Server (NTRS)
Lamb, Don Q.; Melia, F.
1988-01-01
The evolution of magnetic cataclysmic binaries is reviewed, with emphasis on the synchronization process by which DQ Herculis stars become AM Herculis stars. The various mechanisms that are thought to drive the evolution of cataclysmic binaries are discussed, and the criterion for stream versus disk accretion, the physics of the accretion and synchronization torques, and the conditions required for synchronization are described. The different physical regimes to which magnetic cataclysmic binaries belong are summarized, and how synchronization may be achieved, and how it may be broken, are considered.
The Impact of Accurate Distances on UV Spectroscopy of White Dwarfs and Cataclysmic Variables
2009-01-01
evolution. Four instability strips in the HR diagram are associated with planetary nebulae nuclei (PNN) and white dwarfs (WDs). The rst instability...strip occurs during the high luminosity planetary nebula phase. The second is during the pre- WD stars of the PG 1159 spectral type, which are direct
NASA Astrophysics Data System (ADS)
Gabdeev, M. M.; Shimanskiy, V. V.; Borisov, N. V.; Tazieva, Z. R.
2017-06-01
We present spectroscopic investigations of a cataclysmic variable star, YY Sex. There are some uncertainties in the classification of this object. We calculate Doppler maps for Hβ and HeII λ4686Å and show that there is no sign of disk accretion in YY Sex. Consequently, we conclude that YY Sex is a polar.
A possible giant planet orbiting the cataclysmic variable LX Ser
NASA Astrophysics Data System (ADS)
Li, Kai; Hu, Shaoming; Zhou, Jilin; Wu, Donghong; Guo, Difu; Jiang, Yunguo; Gao, Dongyang; Chen, Xu; Wang, Xianyu
2017-04-01
LX Ser is a deeply eclipsing cataclysmic variable with an orbital period of 0.1584325 d. 62 new eclipse times were determined by our observations and the AAVSO International Data base. Combining all available eclipse times, we analyzed the O - C behavior of LX Ser. We found that the O - C diagram of LX Ser shows a sinusoidal oscillation with a period of 22.8 yr and an amplitude of 0.00035 d. Two mechanisms (i.e., the Applegate mechanism and the light-travel time effect) are applied to explain the cyclic modulation. We found that it is difficult to apply the Applegate mechanism to explain the cyclic oscillation in the orbital period. Therefore, the cyclic period change is most likely to be caused by the light-travel time effect due to the presence of a third body. The mass of the tertiary component was determined to be M3 ∼ 7.5 MJup. We supposed that the tertiary companion is plausibly a giant planet. The stability of the giant planet was checked, and we found that the multiple system is stable.
NASA Technical Reports Server (NTRS)
Shafter, A. W.; Szkody, P.; Thorstensen, J. R.
1986-01-01
Time-resolved X-ray and optical photometric and optical spectroscopic observations of the ultrashort period cataclysmic variable SW UMa are reported. The spectroscopic observations reveal the presence of an s-wave component which is almost in phase with the extreme line wings and presumably the white dwarf. This very unusual phasing in conjunction with the available optical and X-ray data seems to indicate that a region of enhanced emission exists on the opposite side of the disk from the expected location of the hot spot. The photometric observations reveal the presence of a hump in the light curve occurring at an orbital phase which is consistent with the phase at which the region of enhanced line emission is most favorably seen. Changes in the hump amplitude are seen from night to night, and a 15.9 min periodicity is evident in the light curve. The optical and X-ray periodicities suggest that SW UMa is a member of the DQ Her class of cataclysmic variables.
New Southern Cataclysmic Variables: Discoveries from MASTER-SAAO
NASA Astrophysics Data System (ADS)
Buckley, D. A. H.; Potter, S. B.; Kniazev, A.; Lipunov, V.; Gorbovskoy, E.; Tiurina, N.
2017-03-01
In this paper we report on new cataclysmic variables (CVs) discovered by the first local optical transient detection system established at the SAAO Sutherland station, namely MASTER-SAAO. The characteristics of the MASTER-SAAO system are described and the parameters of the survey compared to the Catalina Real Time Survey (CRTS). To date MASTER-SAAO has discovered over 200 (non-Solar System) optical transients with about 75% of these being likely new CVs, most being dwarf novae (DNe). Approximately 50% of the DNe have outburst amplitudes in excess of 4 magnitudes, with some extreme amplitude (> 7 mag), probable WZ Sge systems. The MASTER-SAAO detection limit of B = 19-20 is comparable to the ˜20 magnitude limit of the CRTS (depending on CV colour). Based on the CV detection statistics of CRTS, we believe that MASTER-SAAO is detecting essentially the same CV population as CRTS, for a detection outburst amplitude threshold >2.2 magnitudes. We also present results of the initial follow-up program on CVs discovered by MASTER, including dwarf novae, a bright new VY Scl system and a new eclipsing polar.
NASA Astrophysics Data System (ADS)
Howell, Steve B.; Brinkworth, Carolyn; Hoard, D. W.; Wachter, Stefanie; Harrison, Thomas; Chun, Howard; Thomas, Beth; Stefaniak, Linda; Ciardi, David R.; Szkody, Paula; van Belle, Gerard
2006-07-01
We present the first observations of magnetic cataclysmic variables using the Spitzer Space Telescope. We used the Infrared Array Camera to obtain photometry of the Polars EF Eri, GG Leo, V347 Pav, and RX J0154.0-5947 at 3.6, 4.5, 5.8, and 8.0 μm, respectively. In all of our targets, we detect excess mid-infrared emission over that expected from the component stars alone. We explore the origin of this IR excess by examining bremsstrahlung, cyclotron emission, circumbinary dust, and L/T brown dwarf secondary stars. Bremsstrahlung and cyclotron emission appear unlikely to be significant contributors to the observed fluxes. At present, the most likely candidate for the excess emission is dust that is probably located in a circumbinary disk with an inner temperature near 800 K. However, a simple dust disk plus any reasonable low-mass or brown dwarf-like secondary star is unable to fully explain the observed flux densities in the 3-8 μm region.
Smith, Nicole E I; Rhodes, Ryan E; Naylor, Patti-Jean; McKay, Heather A
2008-01-01
Previous research suggests that there is limited evidence to support a negative association between physical activity (PA) behaviors and television (TV) viewing time in children. The purpose of this study was to extend the research involving PA-TV viewing relationships and to explore potential moderators, including gender, ethnicity, weekday/ weekend behaviors, structured/unstructured activities, and seasonal variability. A 9-month longitudinal design, across one school year, with assessments every 3 months. Elementary schools in the Vancouver and Richmond districts of British Columbia, Canada. Subjects. Subjects (N = 344; 47% female) were 9- to 11-year-old children who participated in a school-based PA initiative from September 2003 to June 2004. Not applicable. Assessments of PA were measured using the Physical Activity Questionnaire for Children. TV viewing time and structured PA were measured using a self-report questionnaire. Basic descriptives, Pearson r bivariate correlations and moderated multiple regressions with mean centered variables. No significant interaction effects were found for any of the proposed moderators. Null bivariate correlations are supportive of findings in previous literature. Our results did not find support for PA-TV viewing relations, regardless of gender, ethnicity, structured PA, and seasonal variability. PA interventions aimed at modifying sedentary behaviors, such as TV viewing, may not be warranted.
ERIC Educational Resources Information Center
Atkin, Charles K.
This report, the fifth in a series of six reports on television advertising and children, describes the key content dimensions of network advertising messages presented on two comparable Saturday mornings in 1972 and 1973. A total of 470 advertisements was systematically and quantitatively analyzed along 28 variables involving the nature of…
PN G068.1+11.0: A young pre-cataclysmic variable with an extremely hot primary
NASA Astrophysics Data System (ADS)
Mitrofanova, A. A.; Shimansky, V. V.; Borisov, N. V.; Spiridonova, O. I.; Gabdeev, M. M.
2016-02-01
An analysis of spectroscopic and photometric data for the young pre-cataclysmic variable (PCV) PN G068.1+11.0, which passed through its common-envelope stage relatively recently, is presented. The spectroscopic and photometric data were obtained with the 6-m telescope and Zeiss-1000 telescope of the Special Astrophysical Observatory. The light curves show sinusoidal brightness variations with the orbital-period time scale and brightness-variation amplitudes of Δ m = 1. m41, 1. m62, and 1. m57 in the B, V, and R bands, respectively. The system's spectrum exhibits weak HI (H β-H δ) andHeII λλ4541, 4686, 5411 Å absorption lines during the phases of minimum brightness, as well as HI, HeII, CIII, CIV, NIII, and OII emission lines whose intensity variations are synchronized with variations of the integrated brightness of the system. The emission-line formation in the spectra can be fully explained by the effects of fluorescence of the ultraviolet light from the primary at the surface of the cool star. All the characteristics of the optical light of PN G068.1+11.0 confirm that it is a young PCV containing sdO subdwarf. The radial velocities were measured from a blend of lines of moderately light elements, CIII+NIII λ4640 Å, which is formed at the surface of the secondary due to reflection effects. The ephemeris of the system has been improved through a joint analysis of the radial-velocity curves and light curves of pre-cataclysmic variable, using modelling of the reflection effects. The fundamental parameters of PN G068.1+11.0 have been determined using two evolutionary tracks for planetary-nebula nuclei of different masses (0.7 M ⊙and 0.78 M ⊙). The model spectra for the system and a comparison with the observations demonstrate the possibility of refining the components' effective temperatures if the quality of the spectra used is improved.
Lessons from accretion disks in cataclysmic variables
NASA Astrophysics Data System (ADS)
Horne, Keith
1998-04-01
We survey recent progress in the interpretation of observations of cataclysmic variables, whose accretion disks are heated by viscous dissipation rather than irradiation. Many features of standard viscous accretion disk models are confirmed by tomographic imaging studies of dwarf novae. Eclipse maps indicate that steady disk temperature structures are established during outbursts. Doppler maps of double-peaked emission lines suggest disk chromospheres heated by magnetic activity. Gas streams impacting on the disk rim leave expected signatures both in the eclipses and emission lines. Doppler maps of dwarf nova IP Peg at the beginning of an outburst show evidence for tidally-induced spiral shocks. While enjoying these successes, we must still face up to the dreaded ``SW Sex syndrome'' which afflicts most if not all cataclysmic variables in high accretion states. The anomalies include single-peaked emission lines with skewed kinematics, flat temperature-radius profiles, shallow offset line eclipses, and narrow low-ionization absorption lines at phase 0.5. The enigmatic behavior of AE Aqr is now largely understood in terms of a magnetic propeller model in which the rapidly spinning white dwarf magnetosphere expels the gas stream out of the system before an accretion disk can form. A final piece in this puzzle is the realization that an internal shock zone occurs in the exit stream at just the right place to explain the anomalous kinematics and violent flaring of the single-peaked emission lines. Encouraged by this success, we propose that disk-anchored magnetic propellers operate in the high accretion rate systems afflicted by the SW Sex syndrome. Magnetic fields anchored in the Keplerian disk sweep forward and apply a boost that expels gas stream material flowing above the disk plane. This working hypothesis offers a framework on which we can hang all the SW Sex anomalies. The lesson for theorists is that magnetic links appear to be transporting energy and angular momentum from the inner disk to distant parts of the flow without associated viscous heating in the disk.
Possible new VY Scl-type variable 1RXS J075330.1+044606
NASA Astrophysics Data System (ADS)
Sokolovsky, K.; Denisenko, D.; Mescheryakov, A.; Tkachenko, A.; Korotkiy, S.; Gerke, V.
2012-02-01
We report the discovery of a possible new VY Scl-type cataclysmic variable associated with previously unidentified X-ray source 1RXS J075330.1+044606. The variable optical object USNO-B1.0 0947-0148659 (07:53:30.78 +04:45:56.3, J2000) located 15" from the X-ray source listed in the ROSAT All Sky Survey Faint Source Catalog (Voges et al., 2000, IAUC, 7432) was identified from information listed in the USNO-B1.0 catalog (Monet et al.
NASA Astrophysics Data System (ADS)
Shara, Michael M.; Drissen, Laurent; Martin, Thomas; Alarie, Alexandre; Stephenson, F. Richard
2017-02-01
The Z Cam-type dwarf nova AT Cancri (AT Cnc) displays a classical nova (CN) shell, demonstrating that mass transfer in cataclysmic binaries decreases substantially after a CN eruption. The hibernation scenario of cataclysmic binaries predicts such a decrease, on a time-scale of a few centuries. In order to measure the time since AT Cnc's last CN eruption, we have measured the radial velocities of a hundred clumps in its ejecta with SITELLE, Canada-France-Hawaii Telescope's recently commissioned imaging Fourier transform spectrometer. These range from -455 to +490 km s-1. Coupled with the known distance to AT Cnc of 460 pc, the size of AT Cnc's shell, and a simple model of nova ejecta deceleration, we determine that the last CN eruption of this system occurred 330_{-90}^{+135} yr ago. This is the most rapid transition from a high mass-transfer rate, nova-like variable to a low mass-transfer rate, dwarf nova yet measured, and in accord with the hibernation scenario of cataclysmic binaries. We conclude by noting the similarity in the deduced outburst date (within a century of 1686 CE) of AT Cnc to a `guest star' reported in the constellation Cancer by Korean observers in 1645 CE.
A magnetic accretion switch in pre-cataclysmic binaries
NASA Astrophysics Data System (ADS)
Drake, Jeremy J.; Garraffo, Cecilia; Takei, Dai; Gaensicke, Boris
2014-02-01
We have investigated the mass accretion rate implied by published surface abundances of Si and C in the white dwarf component of the 3.62 h period pre-cataclysmic binary and planet host candidate QS Vir (DA+M2-4). Diffusion time-scales for gravitational settling imply dot{M} ˜ 10^{-16} M_{odot } yr-1 for the 1999 epoch of the observations, which is three orders of magnitude lower than measured from a 2006 XMM-Newton observation. This is the first time that large accretion rate variations have been seen in a detached pre-cataclysmic variable (pre-CV). A third body in a 14 yr eccentric orbit suggested in a recent eclipse timing study is too distant to perturb the central binary sufficiently to influence accretion. A hypothetical coronal mass ejection just prior to the XMM-Newton observation might explain the higher accretion rate, but the implied size and frequency of such events appear too great. We suggest accretion is most likely modulated by a magnetic cycle on the secondary acting as a wind `accretion switch', a mechanism that can be tested by X-ray and ultraviolet monitoring. If so, QS Vir and similar pre-CVs could provide powerful insights into hitherto inscrutable CV and M dwarf magnetospheres, and mass- and angular-momentum-loss rates.
Slater, Michael D.; Jain, Parul
2011-01-01
This study examined the hypotheses that media exposure and attention would predict, and partially mediate, the effects of various individual-difference variables on alcohol-related risk perceptions among teen viewers of crime and emergency (e.g. medical drama) shows on television. Risk perceptions including perceived severity, perceived alcohol-attributable fraction of incidents involving alcohol, controllability, and concern regarding alcohol-related crime, assaults, and other injuries were the outcome measures. Attention to crime and emergency shows was predictive of increased concern and other risk perceptions regarding alcohol-related incidents. Attention also partially mediated the effects of demographic and other individual difference variables on adolescents’ risk perceptions regarding alcohol-related injuries. The findings a) suggest emergency and medical drama television narratives can at times have incidental positive impacts on health-related attitudes and b) provide further evidence regarding the endogenous nature of media use variables in influencing such attitudes. PMID:21240701
Slater, Michael D; Jain, Parul
2011-01-01
This study examined the hypotheses that media exposure and attention would predict, and partially mediate, the effects of various individual-difference variables on alcohol-related risk perceptions among teen viewers of crime and emergency (e.g., medical drama) shows on television. Risk perceptions including perceived severity, perceived alcohol-attributable fraction of incidents involving alcohol, controllability, and concern regarding alcohol-related crime, assaults, and other injuries were the outcome measures. Attention to crime and emergency shows was predictive of increased concern and other risk perceptions regarding alcohol-related incidents. Attention also partially mediated the effects of demographic and other individual difference variables on adolescents' risk perceptions regarding alcohol-related injuries. The findings (a) suggest emergency and medical drama television narratives can at times have incidental positive impacts on health-related attitudes and (b) provide further evidence regarding the endogenous nature of media use variables in influencing such attitudes.
Cataclysmic variables based on the stellar spectral survey LAMOST DR3
NASA Astrophysics Data System (ADS)
Han, Xianming L.; Zhang, Li-Yun; Shi, Jian-Rong; Pi, Qing-Feng; Lu, Hong-Peng; Zhao, Li-Bo; Terheide, Rachel K.; Jiang, Lin-Yang
2018-06-01
Big data in the form of stellar spectra from the spectroscopic survey associated with the Large Sky Area Multi-object Fiber Spectroscopic Telescope (LAMOST) are important for studying properties of cataclysmic variables (CVs). By cross matching the catalogs of CVs compiled with LAMOST DR3, acquired from October 2011 to July 2015, we obtained the first spectroscopic catalog for CVs observed by LAMOST with high signal to noise ratio, above 8. By integrating line profiles, their equivalent widths (EWs) of the Hα, Hβ, Hγ and Hδ, as well as He I 5876 and 6678 Å lines, were calculated. There were 74 stellar spectra from 48 known CVs and three spectra from three new CV candidates. At the same time, we also collected their previously published EWs. Thirty-three objects had repeated spectra and 30 stars showed spectral variability in the Hα line. Moreover, we carried out photometric follow-up studies for five CVs (UU Aqr, TT Tri, PX And, BP Lyn and RW Tri). We obtained nine new light curves and revised their linear ephemerides. For RW Tri, there is a possible oscillation with an amplitude of 0.0031(2) days and a period of 47.6 ± 0.4 years, which might be caused by a third body (brown dwarf) or magnetic activity cycle.
BOKS 45906: a CV with an orbital period of 56.6 min in the Kepler field?
NASA Astrophysics Data System (ADS)
Ramsay, Gavin; Howell, Steve B.; Wood, Matt A.; Smale, Alan; Barclay, Thomas; Seebode, Sally A.; Gelino, Dawn; Still, Martin; Cannizzo, John K.
2014-02-01
BOKS 45906 was found to be a blue source in the Burrell-Optical-Kepler Survey which showed a 3 mag outburst lasting ˜5 d. We present the Kepler light curve of this source which covers nearly 3 years. We find that it is in a faint optical state for approximately half the time and shows a series of outbursts separated by distinct dips in flux. Using data with 1 min sampling, we find clear evidence that in its low state BOKS 45906 shows a flux variability on a period of 56.5574 ± 0.0014 min and a semi-amplitude of ˜3 per cent. Since we can phase all the 1 min cadence data on a common ephemeris using this period, it is probable that 56.56 min is the binary orbital period. Optical spectra of BOKS 45906 show the presence of Balmer lines in emission indicating it is not an AM CVn (pure Helium) binary. Swift data show that it is a weak X-ray source and is weakly detected in the bluest of the UVOT filters. We conclude that BOKS 45906 is a cataclysmic variable with a period shorter than the `period-bounce' systems and therefore BOKS 45906 could be the first helium-rich cataclysmic variable detected in the Kepler field.
Niederdeppe, Jeff
2014-01-01
Cultivation theory and research has been criticized for its failure to consider variation in effects by genre, employ appropriate third-variable controls, and determine causal direction. Recent studies, controlling for a variety of demographic characteristics and media use variables, have found that exposure to local television (TV) newscasts is associated with a variety of problematic “real-world” beliefs. However, many of these studies have not adequately assessed causal direction. Redressing this limitation, we analyzed data from a two-wave national representative survey which permitted tests of lagged association between overall TV viewing, local TV news viewing, and fatalistic beliefs about cancer prevention. We first replicated the original cultivation effect and found a positive association between overall TV viewing at time 1 and increased fatalistic beliefs about cancer prevention at time 2. Analyses also provided evidence that local TV news viewing at time 1 predicts increased fatalistic beliefs about cancer prevention at time 2. There was little evidence for reverse causation in predicting changes in overall TV viewing or local TV news viewing. The paper concludes with a discussion of theoretical and practical implications of these findings. PMID:25605981
Children's attitudes toward violence on television.
Hough, K J; Erwin, P G
1997-07-01
Children's attitudes toward television violence were studied. A 47-item questionnaire collecting attitudinal and personal information was administered to 316 children aged 11 to 16 years. Cluster analysis was used to split the participants into two groups based on their attitudes toward television violence. A stepwise discriminant function analysis was performed to determine which personal characteristics would predict group membership. The only significant predictor of attitudes toward violence on television was the amount of television watched on school days (p < .05), but we also found that the impact of other predictor variables may have been mediated by this factor.
Associations between media use and health in US children.
Russ, Shirley A; Larson, Kandyce; Franke, Todd Michael; Halfon, Neal
2009-01-01
Television viewing has been associated with poorer health attributes, but relationships between computer use and health are less clear. The aim of this study was to determine associations between TV and computer use, both separately and combined, and health attributes in US children. We performed bivariate and multivariate logistic regression analyses of cross-sectional data on 54 863 children ages 6 to 17 years who participated in the National Survey of Children's Health. Key independent variables were TV, computer, and combined media use; outcome variables were 6 measures of health. In models controlling for a wide range of sociodemographic variables, each additional hour of television viewing was associated with greater odds of overweight/obesity (odds ratio [OR] 1.05, 95% confidence interval (95% CI) 1.02-1.08), poorer oral health (OR 1.05, 95% CI 1.02-1.09), social-emotional problems (OR 1.08, 95% CI 1.05-1.11), concern about self-esteem, and lower social competence. Greater computer use was associated only with overweight/obesity (OR 1.04, 95% CI 1.01-1.07). Combined media use showed similar, but weaker, health associations to television viewing alone. Interaction analyses showed that TV viewing was associated with overweight/obesity only for white, not black or Hispanic, children. TV/video use is associated with a broader range of negative physical and social-emotional health attributes than computer use. Associations between media use and health are modest, but persistent at the population level. TV/video use reduction strategies may lead to improved physical and social-emotional population health. However, reductions in TV viewing may have little effect on overweight/obesity in black or Hispanic children. Mechanisms underlying observed health associations need further study.
Three New Z Cam Stars (Abstract)
NASA Astrophysics Data System (ADS)
Simonsen, M.
2016-12-01
(Abstract only) I will present the evidence and discovery stories of three cataclysmic variables who appear to be members of the Z Cam class of dwarf novae. One discovered by a lone visual observer and his unwavering patience and persistence, one through the directed effort of the ongoing Z CamPaign and one via survey data from the Gaia satellite.
How Adolescents Counterargue Television Beer Advertisements: Implications for Education Efforts.
ERIC Educational Resources Information Center
Slater, Michael D.; Rouner, Donna; Domenech-Rodriguez, Melanie; Beauvais, Frederick; Murphy, Kevin; Estes, Emily
1998-01-01
Examined types of counterarguments generated by Anglo and Latino adolescents exposed to television beer ads, noting counterargument differences based on demographic and behavioral variables. Questionnaires and comments from the students indicated that without any cues, they responded with counterarguments, though counterarguments represented only…
Exploring the Hard and Soft X-ray Emission of Magnetic Cataclysmic Variables
NASA Astrophysics Data System (ADS)
de Martino, D.; Anzolin, G.; Bonnet-Bidaud, J.-M.; Falanga, M.; Matt, G.; Mouchet, M.; Mukai, K.; Masetti, N.
2009-05-01
A non-negligible fraction of galactic hard (>20 keV) X-ray sources were identified as CVs of the magnetic Intermediate Polar type in INTEGRAL, SWIFT and RXTE surveys, that suggests a still hidden but potentially important population of faint hard X-ray sources. Simbol-X has the unique potential to simultaneously characterize their variable and complex soft and hard X-ray emission thus allowing to understand their putative role in galactic populations of X-ray sources.
The Preschool Child's Comprehension of Television Commercial Disclaimers.
ERIC Educational Resources Information Center
Jalongo, Mary Renck
The major purposes of this investigation were (1) to contribute to existing research on the preschool child's comprehension of disclaimers in television commercials, (2) to identify specific standard or modified disclaimers that are understood by preschoolers, and (3) to determine logical relationships between study variables. Disclaimers were…
Prosocial Television and Children's Fantasy.
ERIC Educational Resources Information Center
Fox, Sandra; And Others
This study, part of a larger study on the effects of prosocial television and environmental variables on children's behavior, analyzed fantasy structure and content characteristics. Also investigated were possible effects of treatment and sex. Following a baseline period, 142 lower-class children were assigned to one of four experimental…
The effect of television news items on intimate partner violence murders.
Vives-Cases, C; Torrubiano-Domínguez, J; Alvarez-Dardet, C
2009-12-01
This study has been carried out in order to explore the effect of the growing appearance of IPV in television news items on deaths by this cause. Ecological study based on 340 deaths by intimate partner violence (IPV) and 3733 television news items covering this topic on Spanish television channels (2003 and 2007). Logistic regression analysis was carried out. Dependent variable: the difference between the number of IPV deaths in the 7 days following a news item broadcast and the number of IPV deaths in the 7 days before a media item. This outcome variable was conceptualised as a binary variable: increase vs. no increase. days with IPV news items-in general, concerning deaths, measures or other IPV crimes. Adjusted variables: day of the week, month, year and public holidays. A small copycat effect was observed in the IPV murder rate (RR = 1.32, CI(95%) = 1.07 - 1.62) for IPV-related news item days compared with days without such news. This effect continued when information about deaths was broadcast (RR = 1.28, CI(95%) = 1.01 - 1.62). News items concerning measures (RR = 0.90, CI(95%) = 0.82 - 0.98) or other IPV crimes (0.84, CI(95%) = 0.82 - 0.98) were related to a lower possibility of an increase in deaths compared with days with death-related news. Given the results observed in the case of IPV-related news, there is an evident need to develop a journalistic style guide in order to determine what type of information is recommended due to the potential positive or negative effects.
The first sub-70 min non-interacting WD-BD system: EPIC212235321
NASA Astrophysics Data System (ADS)
Casewell, S. L.; Braker, I. P.; Parsons, S. G.; Hermes, J. J.; Burleigh, M. R.; Belardi, C.; Chaushev, A.; Finch, N. L.; Roy, M.; Littlefair, S. P.; Goad, M.; Dennihy, E.
2018-05-01
We present the discovery of the shortest period, non-interacting, white dwarf-brown dwarf post-common-envelope binary known. The K2 light curve shows the system, EPIC 21223532 has a period of 68.2 min and is not eclipsing, but does show a large reflection effect due to the irradiation of the brown dwarf by the white dwarf primary. Spectra show hydrogen, magnesium, and calcium emission features from the brown dwarf's irradiated hemisphere, and the mass indicates the spectral type is likely to be L3. Despite having a period substantially lower than the cataclysmic variable period minimum, this system is likely a pre-cataclysmic binary, recently emerged from the common-envelope. These systems are rare, but provide limits on the lowest mass object that can survive common-envelope evolution, and information about the evolution of white dwarf progenitors, and post-common-envelope evolution.
Antecedents of Children's Comprehension of the Purpose of Television Advertising.
ERIC Educational Resources Information Center
Faber, Ronald J.; And Others
A study was conducted to compare the relative importance of several different variables from different theoretical perspectives in explaining how children understood the advertising on commercial television. Sixty-seven first and third grade students were interviewed individually to assess their current stage of logical operations and role taking,…
Improving Audience Learning from Television News through Between-Channel Redundancy.
ERIC Educational Resources Information Center
Reese, Stephen D.
A study tested the effects of between-channel redundancy on television news learning. Redundancy, defined as shared information, was proposed as an explanatory variable that considers the relationship between information in three channels: the audio, the nonverbal pictorial, and visual-verbal print channel. It was hypothesized that pictures would…
Toward an Etiology of Media Use Motivations: The Role of Temperament in Media Use.
ERIC Educational Resources Information Center
Sherry, John L.
2001-01-01
Shows that the biologically rooted individual difference behavior variable of temperament was consistent and moderately strong causal factor in forming television use motivations among undergraduate students. Finds distinct patterns of relationships between temperament and all television use gratifications supporting the uses and gratifications…
Schimek-Jasch, Tanja; Troost, Esther G C; Rücker, Gerta; Prokic, Vesna; Avlar, Melanie; Duncker-Rohr, Viola; Mix, Michael; Doll, Christian; Grosu, Anca-Ligia; Nestle, Ursula
2015-06-01
Interobserver variability in the definition of target volumes (TVs) is a well-known confounding factor in (multicentre) clinical studies employing radiotherapy. Therefore, detailed contouring guidelines are provided in the prospective randomised multicentre PET-Plan (NCT00697333) clinical trial protocol. This trial compares strictly FDG-PET-based TV delineation with conventional TV delineation in patients with locally advanced non-small cell lung cancer (NSCLC). Despite detailed contouring guidelines, their interpretation by different radiation oncologists can vary considerably, leading to undesirable discrepancies in TV delineation. Considering this, as part of the PET-Plan study quality assurance (QA), a contouring dummy run (DR) consisting of two phases was performed to analyse the interobserver variability before and after teaching. In the first phase of the DR (DR1), radiation oncologists from 14 study centres were asked to delineate TVs as defined by the study protocol (gross TV, GTV; and two clinical TVs, CTV-A and CTV-B) in a test patient. A teaching session was held at a study group meeting, including a discussion of the results focussing on discordances in comparison to the per-protocol solution. Subsequently, the second phase of the DR (DR2) was performed in order to evaluate the impact of teaching. Teaching after DR1 resulted in a reduction of absolute TVs in DR2, as well as in better concordance of TVs. The Overall Kappa(κ) indices increased from 0.63 to 0.71 (GTV), 0.60 to 0.65 (CTV-A) and from 0.59 to 0.63 (CTV-B), demonstrating improvements in overall interobserver agreement. Contouring DRs and study group meetings as part of QA in multicentre clinical trials help to identify misinterpretations of per-protocol TV delineation. Teaching the correct interpretation of protocol contouring guidelines leads to a reduction in interobserver variability and to more consistent contouring, which should consequently improve the validity of the overall study results.
Exploratory Spectroscopy of Magnetic Cataclysmic Variables Candidates and Other Variable Objects
NASA Astrophysics Data System (ADS)
Oliveira, A. S.; Rodrigues, C. V.; Cieslinski, D.; Jablonski, F. J.; Silva, K. M. G.; Almeida, L. A.; Rodríguez-Ardila, A.; Palhares, M. S.
2017-04-01
The increasing number of synoptic surveys made by small robotic telescopes, such as the photometric Catalina Real-Time Transient Survey (CRTS), provides a unique opportunity to discover variable sources and improves the statistical samples of such classes of objects. Our goal is the discovery of magnetic Cataclysmic Variables (mCVs). These are rare objects that probe interesting accretion scenarios controlled by the white-dwarf magnetic field. In particular, improved statistics of mCVs would help to address open questions on their formation and evolution. We performed an optical spectroscopy survey to search for signatures of magnetic accretion in 45 variable objects selected mostly from the CRTS. In this sample, we found 32 CVs, 22 being mCV candidates, 13 of which were previously unreported as such. If the proposed classifications are confirmed, it would represent an increase of 4% in the number of known polars and 12% in the number of known IPs. A fraction of our initial sample was classified as extragalactic sources or other types of variable stars by the inspection of the identification spectra. Despite the inherent complexity in identifying a source as an mCV, variability-based selection, followed by spectroscopic snapshot observations, has proved to be an efficient strategy for their discoveries, being a relatively inexpensive approach in terms of telescope time. Based on observations obtained at the Observatório do Pico dos Dias/LNA, and at the Southern Astrophysical Research (SOAR) telescope, which is a joint project of the Ministério da Ciência, Tecnologia, e Inovação (MCTI) da República Federativa do Brasil, the U.S. National Optical Astronomy Observatory (NOAO), the University of North Carolina at Chapel Hill (UNC), and Michigan State University (MSU).
NASA Technical Reports Server (NTRS)
Catura, Richard C.
1993-01-01
The objective of this research was to study the halo surrounding the ROSAT image of the cataclysmic variable AM Her that is formed by scattering of x-rays by interstellar dust grains. AM Her was in a low state of x-ray emission during the 14,400 sec observation and thus an insufficient number of counts were obtained to detect the x-ray halo.
Doppler tomography and photometry of the cataclysmic variable 1RXS J064434.5+334451
NASA Astrophysics Data System (ADS)
Hernández Santisteban, J. V.; Echevarría, J.; Michel, R.; Costero, R.
2017-01-01
We have obtained simultaneous photometric and spectroscopic observations of the cataclysmic variable 1RXS J064434.5+334451. We have calibrated the spectra for slit losses using simultaneous photometry, allowing us to construct reliable Doppler images from Hα and He II 4686-Å emission lines. We have improved the ephemeris of the object based on new photometric eclipse timings, obtaining HJD = 245 3403.759 533 + 0.269 374 46E. Some eclipses present a clear internal structure, which we attribute to a central He II emission region surrounding the white dwarf, a finding supported by Doppler tomography. This indicates that the system has a large inclination angle I = 78 ± 2°. We have also analysed the radial velocity curve from the emission lines to measure its semi-amplitude, K1, from Hα and He II 4686 and derive the masses of the components M1 = 0.82 ± 0.06 M⊙, M2 = 0.78 ± 0.04 M⊙ and their separation a = 2.01 ± 0.06 R⊙. The Doppler tomography and other observed features in this nova-like system strongly suggest that this is a SW Sex type system.
20 Cataclysmic variables to be observed by William Herschel Telescope
NASA Astrophysics Data System (ADS)
Waagen, Elizabeth O.
2016-05-01
Roque Ruiz-Carmona (Ph.D. candidate, Institute of Mathematics, Astrophysics and Particle Physics, Radboud University Nijmegen, The Netherlands) has requested AAVSO assistance with his campaign to observe a set of 20 cataclysmic variables (CVs) with the William Herschel Telescope (WHT) at La Palma TONIGHT. This campaign is identical in format to the ones successfully carried out by the AAVSO on his behalf in 2015 (AAVSO Alert Notices 524 and 527). The full details of and instructions for this campaign are included here although the first of the two nights for which data are requested has passed. In order for WHT to observe each of the targets safely and to maximize the science value of the observations obtained, it is essential to know whether they are in outburst or quiescence. To this end, the PI has requested our observers to obtain one image of each target on each of TWO separate nights so he may analyze them to determine the final observing list for WHT. The images must be taken and posted within a certain window. Links to finder charts as well as reporting instructions and other information may be found in the full Alert Notice.
Unravelling the role of SW Sextantis stars in the evolution of cataclysmic variables
NASA Astrophysics Data System (ADS)
Araujo-Betancor, Sofia; Gansicke, Boris; Long, Knox; Rodriguez-Gil, Pablo
2005-08-01
SW Sextantis stars are a relatively large group of cataclysmic variables whose properties contradict all predictions made by the current CV evolution theories. Very little is known about the properties of their accreting white dwarfs and their donor stars, as the stellar components are usually outshone by an extremely bright accretion flow. Consequently, a proper assessment of their evolutionary state is illusionary. There is one particular behavior of the SW Sex stars that can allow us to overcome this problem: SW Sex stars exhibit low states during which accretion onto the white dwarf decreases or shuts off completely. Only during this rare occasions we can directly observe the white dwarf and the donor star in these systems, and measurements of the white dwarf temperature, spectral type of the donor, mass and distance to the system can be carried out. With this aim in mind, we have set up a long-term monitoring of a group of five SW Sex stars using the 1.3 m telescope at CTIO. Here we propose to activate follow-up TOOs to obtain optical spectra of the low states to accurately determine the fundamental properties of these systems.
Ultraviolet line diagnostics of accretion disk winds in cataclysmic variables
NASA Technical Reports Server (NTRS)
Vitello, Peter; Shlosman, Isaac
1993-01-01
The IUE data base is used to analyze the UV line shapes of the cataclysmic variables RW Sex, RW Tri, and V Sge. Observed lines are compared to synthetic line profiles computed using a model of rotating biconical winds from accretion disks. The wind model calculates the wind ionization structure self-consistently including photoionization from the disk and boundary layer and treats 3D line radiation transfer in the Sobolev approximation. It is found that winds from accretion disks provide a good fit for reasonable parameters to the observed UV lines which include the P Cygni profiles for low-inclination systems and pure emission at large inclination. Disk winds are preferable to spherical winds which originate on the white dwarf because they: (1) require a much lower ratio of mass-loss rate to accretion rate and are therefore more plausible energetically; (2) provide a natural source for a biconical distribution of mass outflow which produces strong scattering far above the disk leading to P Cygni profiles for low-inclination systems and pure line emission profiles at high inclination with the absence of eclipses in UV lines; and (3) produce rotation-broadened pure emission lines at high inclination.
UV line diagnostics of accretion disk winds in cataclysmic variables
NASA Technical Reports Server (NTRS)
Vitello, Peter; Shlosman, Isaac
1992-01-01
The IUE data base is used to analyze the UV line shapes of cataclysmic variables RW Sex, RW Tri, and V Sge. Observed lines are compared to synthetic line profiles computed using a model of rotating bi-conical winds from accretion disks. The wind model calculates the wind ionization structure self-consistently including photoionization from the disk and boundary layer and treats 3-D line radiation transfer in the Sobolev approximation. It is found that winds from accretion disks provide a good fit for reasonable parameters to the observed UV lines which include the P Cygni profiles for low inclination systems and pure emission at large inclination. Disk winds are preferable to spherical winds which originate on the white dwarf because they (1) require a much lower ratio of mass loss rate to accretion rate and are therefore more plausible energetically, (2) provide a natural source for a bi-conical distribution of mass outflow which produces strong scattering far above the disk leading to P Cygni profiles for low inclination systems, and pure line emission profiles at high inclination with the absence of eclipses in UV lines, and (3) produce rotation broadened pure emission lines at high inclination.
The space density of post-period minimum Cataclysmic Variables
NASA Astrophysics Data System (ADS)
Hernández Santisteban, J. V.; Knigge, C.; Pretorius, M. L.; Sullivan, M.; Warner, B.
2018-01-01
Binary evolution theory predicts that accreting white dwarfs with substellar companions dominate the Galactic population of cataclysmic variables (CVs). In order to test these predictions, it is necessary to identify these systems, which may be difficult if the signatures of accretion become too weak to be detected. The only chance to identify such 'dead' CVs is by exploiting their close binary nature. We have therefore searched the Sloan Digital Sky Survey (SDSS) Stripe 82 area for apparently isolated white dwarfs that undergo eclipses by a dark companion. We found no such eclipses in either the SDSS or Palomar Transient Factory data sets among our sample of 2264 photometrically selected white dwarf candidates within Stripe 82. This null result allows us to set a firm upper limit on the space density, ρ0, of dead CVs. In order to determine this limit, we have used Monte Carlo simulations to fold our selection criteria through a simple model of the Galactic CV distribution. Assuming a TWD = 7500 K, the resulting 2σ limit on the space density of dead CVs is ρ0 ≲ 2 × 10-5 pc-3, where TWD is the typical effective temperature of the white dwarf in such systems.
NASA Astrophysics Data System (ADS)
Hoard, D. W.; Szkody, Paula; Ishioka, Ryoko; Ferrario, L.; Gänsicke, B. T.; Schmidt, Gary D.; Kato, Taichi; Uemura, Makoto
2002-10-01
We present the first far-ultraviolet (FUV) observations of the magnetic cataclysmic variable VV Puppis, obtained with the Far Ultraviolet Spectroscopic Explorer satellite. In addition, we have obtained simultaneous ground-based optical photometric observations of VV Pup during part of the FUV observation. The shapes of the FUV and optical light curves are consistent with each other and with those of past observations at optical, extreme-ultraviolet, and X-ray wavelengths. Time-resolved FUV spectra during the portion of VV Pup's orbit when the accreting magnetic pole of the white dwarf can be seen show an increasing continuum level as the accretion spot becomes more directly visible. The most prominent features in the spectrum are the O VI λλ1031.9, 1037.6 emission lines. We interpret the shape and velocity shift of these lines in the context of an origin in the accretion funnel near the white dwarf surface. A blackbody function with Tbb>~90,000 K provides an adequate fit to the FUV spectral energy distribution of VV Pup. Based on observations with the NASA-CNES-CSA Far Ultraviolet Spectroscopic Explorer. FUSE is operated for NASA by Johns Hopkins University under NASA contract NAS 5-32985.
Screen Color and Reading Performance on Closed-Circuit Television.
ERIC Educational Resources Information Center
Jacobs, R. J.
1990-01-01
To investigate whether screen color is an important variable in the prescription of closed circuit television (CCTV) systems, 16 adults with low vision were assessed on reading performance on white, green, and amber screens. When the screen luminance and contrast were equated for each CCTV, subjects' reading performance was unaffected by screen…
Middle School English Language Learner Electronic Media Usage and Its Relationship to Reading
ERIC Educational Resources Information Center
Ramirez, Bari N.
2012-01-01
A quantitative, correlational prediction study was performed to determine the relationship between English language learner (ELL) use of electronic media and reading proficiency in a large urban middle school in Texas. The predictor variables were viewing television programs in English, viewing television programs in Spanish, using a computer for…
Differing Reactions to Television in Kibbutz and City Children.
ERIC Educational Resources Information Center
Huesmann, L. Rowell; Bachrach, Riva S.
Children's social and cultural environments may affect their perceptions of the reality of television violence. One of the problems in measuring the importance of societal variables is the difficulty in finding children whose social environments have differed for most of their lives in well prescribed ways. An exception to this are kibbutz- and…
A Descriptive Study of Television in the Lives of an Elderly Population.
ERIC Educational Resources Information Center
Davis, Richard Harding
This study sought to determine what influence the following variables had upon the television viewing by an older audience: age, sex, marital status, work status, mobility, health, income, living arrangements, individual interpersonal relationships, family and friends, and the language spoken. Subjects included 300 urban residents and 174 suburban…
Portrayal of Religion in Prime-Time Television Drama.
ERIC Educational Resources Information Center
Virts, Paul H.; Keeler, John D.
In order to stimulate scholars to investigate systematically and fully the religious dimension of dramatic television content, the first part of this paper develops a basic framework for such study. After establishing the importance of this kind of research, it defines and explains the four basic variables that would have to be examined: general…
Toward More Precise Definition and Evaluation of Televised Educational Programming
ERIC Educational Resources Information Center
Aversa Fran; Morrison, Gary R.
1978-01-01
An operational definition of public television programming and its implications for development and production agencies is sorely needed. This article explores some of the components of such a definition and examines the differences in several types of educational programming in terms of specific design and evaluation variables of the program.…
Mak, Yim Wah; Wu, Cynthia Sau Ting; Hui, Donna Wing Shun; Lam, Siu Ping; Tse, Hei Yin; Yu, Wing Yan; Wong, Ho Ting
2014-10-28
Screen viewing is considered to have adverse impacts on the sleep of adolescents. Although there has been a considerable amount of research on the association between screen viewing and sleep, most studies have focused on specific types of screen viewing devices such as televisions and computers. The present study investigated the duration with which currently prevalent screen viewing devices (including televisions, personal computers, mobile phones, and portable video devices) are viewed in relation to sleep duration, sleep quality, and daytime sleepiness among Hong Kong adolescents (N = 762). Television and computer viewing remain prevalent, but were not correlated with sleep variables. Mobile phone viewing was correlated with all sleep variables, while portable video device viewing was shown to be correlated only with daytime sleepiness. The results demonstrated a trend of increase in the prevalence and types of screen viewing and their effects on the sleep patterns of adolescents.
BOKS 45906: a CV with an Orbital Period of 56.6 Min in the Kepler Field?
NASA Technical Reports Server (NTRS)
Ramsay, Gavin; Howell, Steve B.; Wood, Matt A.; Smale, Alan; Barclay, Thomas; Seebode, Sally A.; Gelino, Dawn; Still, Martin; Cannizzo, John K.
2013-01-01
BOKS 45906 was found to be a blue source in the Burrell-Optical-Kepler Survey which showed a 3 magnitude outburst lasting approximately 5 days. We present the Kepler light curve of this source which covers nearly 3 years. We find that it is in a faint optical state for approximately half the time and shows a series of outbursts separated by distinct dips in flux. Using data with 1 minute sampling, we find clear evidence that in its low state BOKS 45906 shows a flux variability on a period of 56.5574 plus or minus 0.0014 minutes and a semi-amplitude of approximately 3 percent. Since we can phase all the 1 minute cadence data on a common ephemeris using this period, it is probable that 56.56 minutes is the binary orbital period. Optical spectra of BOKS 45906 show the presence of Balmer lines in emission indicating it is not an AM CVn (pure Helium) binary. Swift data show that it is a weak X-ray source and is weakly detected in the bluest of the UVOT filters. We conclude that BOKS 45906 is a cataclysmic variable with a period shorter than the 'period-bounce' systems and therefore BOKS 45906 could be the first helium-rich cataclysmic variable detected in the Kepler field.
Busschaert, Cedric; Ridgers, Nicola D; De Bourdeaudhuij, Ilse; Cardon, Greet; Van Cauwenberg, Jelle; De Cocker, Katrien
2016-01-01
More knowledge is warranted about multilevel ecological variables associated with context-specific sitting time among adolescents. The present study explored cross-sectional and longitudinal associations of ecological domains of sedentary behaviour, including socio-demographic, social-cognitive, health-related and physical-environmental variables with sitting during TV viewing, computer use, electronic gaming and motorized transport among adolescents. For this longitudinal study, a sample of Belgian adolescents completed questionnaires at school on context-specific sitting time and associated ecological variables. At baseline, complete data were gathered from 513 adolescents (15.0±1.7 years). At one-year follow-up, complete data of 340 participants were available (retention rate: 66.3%). Multilevel linear regression analyses were conducted to explore cross-sectional correlates (baseline variables) and longitudinal predictors (change scores variables) of context-specific sitting time. Social-cognitive correlates/predictors were most frequently associated with context-specific sitting time. Longitudinal analyses revealed that increases over time in considering it pleasant to watch TV (p < .001), in perceiving TV watching as a way to relax (p < .05), in TV time of parents/care givers (p < .01) and in TV time of siblings (p < .001) were associated with more sitting during TV viewing at follow-up. Increases over time in considering it pleasant to use a computer in leisure time (p < .01) and in the computer time of siblings (p < .001) were associated with more sitting during computer use at follow-up. None of the changes in potential predictors were significantly related to changes in sitting during motorized transport or during electronic gaming. Future intervention studies aiming to decrease TV viewing and computer use should acknowledge the importance of the behaviour of siblings and the pleasure adolescents experience during these screen-related behaviours. In addition, more time parents or care givers spent sitting may lead to more sitting during TV viewing of the adolescents, so that a family-based approach may be preferable for interventions. Experimental study designs are warranted to confirm the present findings.
Busschaert, Cedric; Ridgers, Nicola D.; De Bourdeaudhuij, Ilse; Cardon, Greet; Van Cauwenberg, Jelle; De Cocker, Katrien
2016-01-01
Introduction More knowledge is warranted about multilevel ecological variables associated with context-specific sitting time among adolescents. The present study explored cross-sectional and longitudinal associations of ecological domains of sedentary behaviour, including socio-demographic, social-cognitive, health-related and physical-environmental variables with sitting during TV viewing, computer use, electronic gaming and motorized transport among adolescents. Methods For this longitudinal study, a sample of Belgian adolescents completed questionnaires at school on context-specific sitting time and associated ecological variables. At baseline, complete data were gathered from 513 adolescents (15.0±1.7 years). At one-year follow-up, complete data of 340 participants were available (retention rate: 66.3%). Multilevel linear regression analyses were conducted to explore cross-sectional correlates (baseline variables) and longitudinal predictors (change scores variables) of context-specific sitting time. Results Social-cognitive correlates/predictors were most frequently associated with context-specific sitting time. Longitudinal analyses revealed that increases over time in considering it pleasant to watch TV (p < .001), in perceiving TV watching as a way to relax (p < .05), in TV time of parents/care givers (p < .01) and in TV time of siblings (p < .001) were associated with more sitting during TV viewing at follow-up. Increases over time in considering it pleasant to use a computer in leisure time (p < .01) and in the computer time of siblings (p < .001) were associated with more sitting during computer use at follow-up. None of the changes in potential predictors were significantly related to changes in sitting during motorized transport or during electronic gaming. Conclusions Future intervention studies aiming to decrease TV viewing and computer use should acknowledge the importance of the behaviour of siblings and the pleasure adolescents experience during these screen-related behaviours. In addition, more time parents or care givers spent sitting may lead to more sitting during TV viewing of the adolescents, so that a family-based approach may be preferable for interventions. Experimental study designs are warranted to confirm the present findings. PMID:27936073
Yang, Xiaohui; Chen, Zhe; Wang, Zhenhong; Zhu, Liqi
2017-01-01
The present study examined the relations between preschoolers’ television exposure and executive functions (EF). One hundred and nineteen 3- to 6-year-old children and their parents participated. Parents filled in a questionnaire regarding children’s television viewing time, television content and parental mediation behaviors about their child’s television viewing. The children were asked to finish six EF tasks, including the backward digit span task, the spatial span task, the boy–girl Stroop, the Simon task, the flanker task and the Tower of Hanoi task that assessed working memory, inhibition and planning, respectively. Children’s vocabulary was tested using Peabody Picture Vocabulary Test, and included as control variables in addition to socioeconomic status of the participated families. The results showed that television viewing time and child-directed educational programs were positively associated with EF. In addition, television content fully mediated the effect of television viewing time on EF and parental restrictive approach strategies moderated the effect of television viewing time on EF. PMID:29089912
Just entertainment: effects of TV series about intrigue on young adults
Wang, Fei; Lin, Shengdong; Ke, Xue
2015-01-01
The potential harmful effects of media violence have been studied systematically and extensively. However, very little attention has been devoted to the intrigue and struggles between people depicted in the mass media. A longitudinal randomized experimental group-control group, pretest–posttest design study was conducted to examine the potential effects of this type of TV series on young adults. A typical and popular TV series was select as a stimulus. By scrutinizing the outline of this TV series and inspired by studies of the effects of media violence, one behavioral observation and five scales were adopted as dependent measures. The study did not find any effect of the intrigue TV series on any of the six dependent variables. Finally, possible interference variables or moderators were discussed. PMID:26029127
The role of exposure in posttraumatic stress in youths following the 1995 bombing.
Pfefferbaum, B; Moore, V L; McDonald, N B; Maynard, B T; Gurwitch, R H; Nixon, S J
1999-04-01
This study investigated the relative impact of various forms of exposure to the 1995 Oklahoma City bombing in middle and high school students seven weeks after the incident. We assessed 3210 youths with an instrument that probed for physical, television, and emotional exposure to the bombing and subsequent posttraumatic stress symptomatology and television reactivity. The majority of youths were exposed through physical proximity--hearing and/or feeling the blast--and through television viewing. These types of exposure, as well as emotional exposure, constituted important variables in the development of posttraumatic stress symptoms and television reactivity. Youths with immediate family casualties were more symptomatic than those without.
FUSE Observations of the Bright, Eclipsing Nova-like Cataclysmic Variable, UX UMa (FUSE 2000)
NASA Technical Reports Server (NTRS)
Long, Knox; Froning, Cynthia
2004-01-01
This was a project to study the disk and wind of the eclipsing nova-like variable UX UMa, in order to better define the wind geometry of the system, including the nature of the transition region between the disk photosphere and the supersonic wind. We proposed to use phase resolved spectroscopy of the system, taking advantage of the fact that UX UMa is an eclipsing system, to isolate different regions of the wind and to use a Monte Carlo radiative transfer code to simulate the spectra through the eclipse.
ASAS-SN Discovery of a Possible Galactic Nova ASASSN-18ix
NASA Astrophysics Data System (ADS)
Stanek, K. Z.; Kochanek, C. S.; Shields, J. V.; Thompson, T. A.; Chomiuk, L.; Strader, J.; Shappee, B. J.; Holoien, T. W.-S.; Prieto, J. L.; Dong, Subo; Stritzinger, M.
2018-04-01
During the ongoing All Sky Automated Survey for SuperNovae (ASAS-SN, Shappee et al. 2014), using data from multiple ASAS-SN telescopes, we detect a new bright transient source, possibly a classical nova, but it might also be a young, large amplitude outburst of a cataclysmic variable Object RA (J2000) DEC (J2000) Gal l (deg) Gal b (deg) Disc.
Superoutburst of 0203+56A UV Persei
NASA Astrophysics Data System (ADS)
Waagen, Elizabeth O.
1991-12-01
Cataclysmic variable 0203+56A UV Per is currently undergoing a superoutburst reaching ~11.5 magnitude. SU UMa is also in superoutburst reaching ~11.7 magnitude. Reiki Kushida made a visual discovery of a supernova in NGC 4374 on December 9.844 UT. 1950 Epoch position is set at 12h 22' 31.54", +13° 08' 52.4". Observations of the supernova its magnitude at ~14.7.
Mariner Mars 1971 television picture catalog. Volume 1: Experiment design and picture data
NASA Technical Reports Server (NTRS)
Cutts, J. A.
1974-01-01
A compilation of Mariner 9 television data is presented for the study of the planet Mars and of its two satellites, Phobos and Deimos. The concept of the basic mission, camera characteristics, and various processing techniques of the raw television data recovered from the spacecraft are discussed. Data are arranged into the following disciplines; (1) mapping and geology, (2) polar studies, (3) geodesy, (4) variable surface features, (5) atmospheric phenomena, and (6) satellites. Reproduction and arrangements of approximately 3000 individual pictures and photomosaics are provided.
Gender and Ability Attentional Differences while Watching an Educational Television Program.
ERIC Educational Resources Information Center
Clariana, Roy B.
This study investigated the attention or arousal of above and below average boys and girls while viewing a science television program on videotape. Skin resistance (GSR) was measured by a biosensor attached to a microcomputer and served as the dependent variable. Analysis of the data included a 2x2x8 ANOVA of gender v. ability v. GSR. The…
Martínez-Moyá, María; Navarrete-Muñoz, Eva M; García de la Hera, Manuela; Giménez-Monzo, Daniel; González-Palacios, Sandra; Valera-Gran, Desirée; Sempere-Orts, María; Vioque, Jesús
2014-01-01
To explore the association between excess weight or body mass index (BMI) and the time spent watching television, self-reported physical activity and sleep duration in a young adult population. We analyzed cross-sectional baseline data of 1,135 participants (17-35 years old) from the project Dieta, salud y antropometría en población universitaria (Diet, Health and Anthrompmetric Variables in Univeristy Students). Information about time spent watching television, sleep duration, self-reported physical activity and self-reported height and weight was provided by a baseline questionnaire. BMI was calculated as kg/m(2) and excess of weight was defined as ≥25. We used multiple logistic regression to explore the association between excess weight (no/yes) and independent variables, and multiple linear regression for BMI. The prevalence of excess weight was 13.7% (11.2% were overweight and 2.5% were obese). A significant positive association was found between excess weight and a greater amount of time spent watching television. Participants who reported watching television >2h a day had a higher risk of excess weight than those who watched television ≤1h a day (OR=2.13; 95%CI: 1.37-3.36; p-trend: 0.002). A lower level of physical activity was associated with an increased risk of excess weight, although the association was statistically significant only in multiple linear regression (p=0.037). No association was observed with sleep duration. A greater number of hours spent watching television and lower physical activity were significantly associated with a higher BMI in young adults. Both factors are potentially modifiable with preventive strategies. Copyright © 2013 SESPAS. Published by Elsevier Espana. All rights reserved.
The Lunar Cataclysm and How LRO Can Help Test It
NASA Technical Reports Server (NTRS)
Cohen, Barbara A.
2009-01-01
One of the important outstanding goals of lunar science is understanding the bombardment history of the Moon and calibrating the impact flux curve for extrapolation to the Earth and other terrestrial planets. The "terminal lunar cataclysm," a brief but intense period of bombardment about 3.9 billion years ago, is of particular scientific interest. Radiometric dating of lunar impact-melt rocks forms the backbone of the lunar cataclysm hypothesis. A histogram of precise age determinations of impact-melt rocks shows the characteristics of the classic formulation of the lunar cataclysm hypothesis: a sharp peak at 3.9 Ga, a steep decline after 3.9 Ga perhaps only 20-200 Myr long, and few rocks of impact origin prior to 4.0 Ga.
NASA Astrophysics Data System (ADS)
Soszyński, I.; Pawlak, M.; Pietrukowicz, P.; Udalski, A.; Szymański, M. K.; Wyrzykowski, Ł.; Ulaczyk, K.; Poleski, R.; Kozłowski, S.; Skowron, D. M.; Skowron, J.; Mróz, P.; Hamanowicz, A.
2016-12-01
We present a collection of 450 598 eclipsing and ellipsoidal binary systems detected in the OGLE fields toward the Galactic bulge. The collection consists of binary systems of all types: detached, semi-detached, and contact eclipsing binaries, RS CVn stars, cataclysmic variables, HW Vir binaries, double periodic variables, and even planetary transits. For all stars we provide the I- and V-band time-series photometry obtained during the OGLE-II, OGLE-III, and OGLE-IV surveys. We discuss methods used to identify binary systems in the OGLE data and present several objects of particular interest.
Mak, Yim Wah; Wu, Cynthia Sau Ting; Hui, Donna Wing Shun; Lam, Siu Ping; Tse, Hei Yin; Yu, Wing Yan; Wong, Ho Ting
2014-01-01
Screen viewing is considered to have adverse impacts on the sleep of adolescents. Although there has been a considerable amount of research on the association between screen viewing and sleep, most studies have focused on specific types of screen viewing devices such as televisions and computers. The present study investigated the duration with which currently prevalent screen viewing devices (including televisions, personal computers, mobile phones, and portable video devices) are viewed in relation to sleep duration, sleep quality, and daytime sleepiness among Hong Kong adolescents (N = 762). Television and computer viewing remain prevalent, but were not correlated with sleep variables. Mobile phone viewing was correlated with all sleep variables, while portable video device viewing was shown to be correlated only with daytime sleepiness. The results demonstrated a trend of increase in the prevalence and types of screen viewing and their effects on the sleep patterns of adolescents. PMID:25353062
[Association between television viewing and obesity in Peruvian women].
Poterico, Julio A; Bernabé-Ortiz, Antonio; Loret de Mola, Christian; Miranda, J Jaime
2012-08-01
To assess the association between frequency of television viewing, overweight and obesity in a nationally representative sample of Peruvian women. Secondary analysis of the Demographic and Health Survey 2008 including women aged from 15 to 49 years old. The outcome variables were obesity (body mass index >30 kg/m²) and overweight (body mass index >25 but <30 kg/m²) whereas the exposure variable was frequency of television viewing (never, occasionally, almost every day). Logistic regression taking into account the multistage study design and adjusting for potential confounders was used. Results were presented as adjusted odds ratios (aOR) with 95% confidence intervals (95%CI). A total of 21,712 women were included in the analysis. The prevalence of overweight was 34.7% (95%CI 33.8%;35.7%), and obesity prevalence was 14.3% (95%CI 13.6%;15.1%). Compared to women who never watched television, those who reported watching television occasionally and almost daily were more likely to be obese: aOR 1.7 (95%CI 1.3;-2.3) and aOR 2.6 (95%CI 2.0;3.5), respectively. The magnitude of this association was lower for overweight: aOR 1.2 (95CI 1.3;2.3) and aOR 1.6 (95%CI 1.1;1.4), respectively. The strength of the association was greater in urban areas. Frequency of television viewing was associated with overweight and obesity in Peruvian women and the strength of this association varied by area of residence. These findings can provide input to strategies for obesity prevention in the Peruvian context.
Sisson, Susan B; Sheffield-Morris, Amanda; Spicer, Paul; Lora, Karina; Latorre, Chelsea
2014-04-01
To explore the relation between family structure and obesogenic attributes. Publicly available data from the 2007 National Survey of Children's Health (n=55,094; 11.6 ± 0.04 years; 51.2% male) was analyzed in fall 2012. Predictor variables included marital status (two-parent biological [referent], two-parent blended, single-mother, and other) and number of children. Outcome variables included the presence of a bedroom television (BTV), elevated television (TV) viewing time, insufficient physical activity, and infrequent family meals. Analysis of family structure revealed 63% biological, 11% blended, and 20% single-mother families. Twenty-three percent of children did not have siblings. When family structure variables were considered independently, children in blended (odds ratio (OR): 1.75; 95% confidence interval (CI) 1.45, 2.10) and single-mother homes (1.49; 1.28, 1.74) had higher odds of BTV. Children in blended families had higher odds of elevated TV viewing time (1.28; 1.08, 1.51). Single-mother homes had higher odds of infrequent family meals (1.28; 1.07, 1.52). Families with ≥ 2 children were less likely to have BTV (0.60; 0.54, 0.66) or elevated TV viewing time (0.74; 0.67, 0.82), and to irregularly dine together (0.89; 0.80, 0.99). Diverse family structure was associated with more obesogenic behaviors and environments. The presence of siblings diminished, but did not eliminate, the risk. Copyright © 2014. Published by Elsevier Inc.
NASA Astrophysics Data System (ADS)
Aungwerojwit, A.; Gänsicke, B. T.; Rodríguez-Gil, P.; Hagen, H.-J.; Harlaftis, E. T.; Papadimitriou, C.; Lehto, H.; Araujo-Betancor, S.; Heber, U.; Fried, R. E.; Engels, D.; Katajainen, S.
2005-12-01
We present time-resolved optical spectroscopy and photometry of four relatively bright (V˜14.0-15.5) long-period cataclysmic variables (CVs) discovered in the Hamburg Quasar Survey: HS 0139+0559, HS 0229+8016, HS 0506+7725, and HS 0642+5049. Their respective orbital periods, 243.69±0.49 min, 232.550±0.049 min, 212.7±0.2 min, and 225.90±0.23 min are determined from radial velocity and photometric variability studies. HS 0506+7725 is characterised by strong Balmer and He emission lines, short-period (~10-20 min) flickering, and weak X-ray emission in the ROSAT All Sky Survey. The detection of a deep low state (B≃18.5) identifies HS 0506+7725 as a member of the VY Scl stars. HS 0139+0559, HS 0229+8016, and HS 0642+5049 display thick-disc like spectra and no or only weak flickering activity. HS 0139+0559 and HS 0229+8016 exhibit clean quasi-sinusoidal radial velocity variations of their emission lines but no or very little orbital photometric variability. In contrast, we detect no radial velocity variation in HS 0642+5049 but a noticeable orbital brightness variation. We identify all three systems either as UX UMa-type novalike variables or as Z Cam-type dwarf novae. Our identification of these four new systems underlines that the currently known sample of CVs is rather incomplete even for bright objects. The four new systems add to the clustering of orbital periods in the 3-4 h range found in the sample of HQS selected CVs, and we discuss the large incidence of magnetic CVs and VY Scl/SW Sex stars found in this period range among the known population of CVs.
NASA Technical Reports Server (NTRS)
Pao, Y. H.; Claspy, P.; Allen, J. E.; Merat, F.
1979-01-01
The results are presented of a continuing research and development program the objective of which is to develop a reduced bandwidth television system and a technique for television transmission of holograms. The result of the former is a variable frame rate television system, the operation of which was demonstrated for both black-and-white and color signals. This system employs a novel combination of the inexpensive mass storage capacity of a magnetic disc with the reliability of a digital system for time expansion and compression. Also reported are the results of a theoretical analysis and preliminary feasibility experiment of an innovative system for television transmission of holograms using relatively conventional TV equipment along with a phase modulated reference wave for production of the original interference pattern.
Ross, Craig S.; Maple, Emily; Siegel, Michael; DeJong, William; Naimi, Timothy S.; Ostroff, Joshua; Padon, Alisa A.; Borzekowski, Dina L.G.; Jernigan, David H.
2014-01-01
Background Being able to investigate the relationship between underage drinkers' preferences for particular brands and their exposure to advertising for those brands would represent a significant advance in alcohol marketing research. However, no previous national study has examined the relationship between underage youth exposure to brand-specific alcohol advertising and consumption of those brands. Methods We conducted a cross-sectional, internet-based survey of a national sample of 1,031 youths, ages 13-20, who had consumed at least one drink of alcohol in the past 30 days. We ascertained all alcohol brands consumed by respondents in the past 30 days. The main outcome measure was brand-specific consumption during the past 30 days, measured as a dichotomous variable. The main predictor variable was exposure to brand-specific alcohol advertising on television. The respondents reported which of 20 television shows popular with youth they had watched during the past 30 days. For each respondent, we calculated a standard measure of potential exposure to the brand-specific alcohol advertising that aired on those shows during the preceding 12 months, based on Nielsen (New York, NY) estimates of the youth audience for each show's telecasts. Results Compared to no brand-specific advertising exposure, any exposure was associated with an increased likelihood of brand-specific consumption (adjusted odds ratio 3.02; 95% confidence interval: 2.61-3.49) after controlling for several individual- and brand-level variables. When measured as a continuous variable, the relationship between advertising exposure and brand consumption was nonlinear, with a large association at lower levels of exposure and diminishing incremental effects as the level of exposure increased. Conclusions There is a robust relationship between youth's brand-specific exposure to alcohol advertising on television and their consumption of those same alcohol brands during the past 30 days. This study provides further evidence of a strong association between alcohol advertising and youth drinking behavior. PMID:24986257
Ross, Craig S; Maple, Emily; Siegel, Michael; DeJong, William; Naimi, Timothy S; Ostroff, Joshua; Padon, Alisa A; Borzekowski, Dina L G; Jernigan, David H
2014-08-01
Being able to investigate the relationship between underage drinkers' preferences for particular brands and their exposure to advertising for those brands would represent a significant advance in alcohol marketing research. However, no previous national study has examined the relationship between underage youth exposure to brand-specific alcohol advertising and consumption of those brands. We conducted a cross-sectional, Internet-based survey of a national sample of 1,031 youth, ages 13-20, who had consumed at least 1 drink of alcohol in the past 30 days. We ascertained all alcohol brands consumed by respondents in the past 30 days. The main outcome measure was brand-specific consumption during the past 30 days, measured as a dichotomous variable. The main predictor variable was exposure to brand-specific alcohol advertising on television. The respondents reported which of 20 television shows popular with youth they had watched during the past 30 days. For each respondent, we calculated a standard measure of potential exposure to the brand-specific alcohol advertising that aired on those shows during the preceding 12 months, based on Nielsen (New York, NY) estimates of the youth audience for each show's telecasts. Compared to no brand-specific advertising exposure, any exposure was associated with an increased likelihood of brand-specific consumption (adjusted odds ratio 3.02; 95% confidence interval: 2.61-3.49) after controlling for several individual- and brand-level variables. When measured as a continuous variable, the relationship between advertising exposure and brand consumption was nonlinear, with a large association at lower levels of exposure and diminishing incremental effects as the level of exposure increased. There is a robust relationship between youth's brand-specific exposure to alcohol advertising on television and their consumption of those same alcohol brands during the past 30 days. This study provides further evidence of a strong association between alcohol advertising and youth drinking behavior. Copyright © 2014 by the Research Society on Alcoholism.
Exploring the SDSS Dataset with Linked Scatter Plots: I. EMP, CEMP, and CV Stars
NASA Technical Reports Server (NTRS)
Carbon, Duane F.; Henze, Christopher; Nelson, Bron C.
2017-01-01
We present the results of a search for EMP, CEMP, and cataclysmic variable stars using a new exploration tool based on linked scatter plots (LSPs). Our approach is especially designed to work with very large spectrum data sets such as the SDSS, LAMOST, RAVE, and Gaia data sets and can be applied to stellar, galaxy, and quasar spectra. As a demonstration, we conduct a search for EMP, CEMP, and cataclysmic variable stars in the SDSS DR10 data set. We first created a 3326-dimensional phase space containing nearly 2 billion measures of the strengths of over 1600 spectral features in 569,738 SDSS stars. These measures capture essentially all the stellar atomic and molecular species visible at the resolution of SDSS spectra. We show how LSPs can be used to quickly isolate and examine interesting portions of this phase space. To illustrate, we use LSPs coupled with cuts in selected portions of phase space to extract EMP stars, C-rich EMP stars, and CV stars. We present identifications for 59 previously unrecognized candidate EMP stars and 11 previously unrecognized candidate CEMP stars. We also call attention to 2 candidate He II emission CV stars found by the LSP approach that have not yet been discussed in the literature.
Exploring the SDSS Dataset with Linked Scatter Plots: I. EMP, CEMP, and CV Stars.
Carbon, Duane F; Henze, Christopher; Nelson, Bron C
2017-02-01
We present the results of a search for EMP, CEMP, and cataclysmic variable stars using a new exploration tool based on linked scatter plots (LSPs). Our approach is especially designed to work with very large spectrum data sets such as the SDSS, LAMOST, RAVE, and Gaia data sets and can be applied to stellar, galaxy, and quasar spectra. As a demonstration, we conduct a search for EMP, CEMP, and cataclysmic variable stars in the SDSS DR10 data set. We first created a 3326-dimensional phase space containing nearly 2 billion measures of the strengths of over 1600 spectral features in 569,738 SDSS stars. These measures capture essentially all the stellar atomic and molecular species visible at the resolution of SDSS spectra. We show how LSPs can be used to quickly isolate and examine interesting portions of this phase space. To illustrate, we use LSPs coupled with cuts in selected portions of phase space to extract EMP stars, C-rich EMP stars, and CV stars. We present identifications for 59 previously unrecognized candidate EMP stars and 11 previously unrecognized candidate CEMP stars. We also call attention to 2 candidate He II emission CV stars found by the LSP approach that have not yet been discussed in the literature.
Exploring the SDSS Dataset with Linked Scatter Plots: I. EMP, CEMP, and CV Stars
Carbon, Duane F.; Henze, Christopher; Nelson, Bron C.
2017-01-01
We present the results of a search for EMP, CEMP, and cataclysmic variable stars using a new exploration tool based on linked scatter plots (LSPs). Our approach is especially designed to work with very large spectrum data sets such as the SDSS, LAMOST, RAVE, and Gaia data sets and can be applied to stellar, galaxy, and quasar spectra. As a demonstration, we conduct a search for EMP, CEMP, and cataclysmic variable stars in the SDSS DR10 data set. We first created a 3326-dimensional phase space containing nearly 2 billion measures of the strengths of over 1600 spectral features in 569,738 SDSS stars. These measures capture essentially all the stellar atomic and molecular species visible at the resolution of SDSS spectra. We show how LSPs can be used to quickly isolate and examine interesting portions of this phase space. To illustrate, we use LSPs coupled with cuts in selected portions of phase space to extract EMP stars, C-rich EMP stars, and CV stars. We present identifications for 59 previously unrecognized candidate EMP stars and 11 previously unrecognized candidate CEMP stars. We also call attention to 2 candidate He II emission CV stars found by the LSP approach that have not yet been discussed in the literature. PMID:28684884
NASA Astrophysics Data System (ADS)
Krauland, Christine; Drake, R.; Loupias, B.; Falize, E.; Busschaert, C.; Ravasio, A.; Yurchak, R.; Pelka, A.; Koenig, M.; Kuranz, C. C.; Plewa, T.; Huntington, C. M.; Kaczala, D. N.; Klein, S.; Sweeney, R.; Villete, B.; Young, R.; Keiter, P. A.
2012-05-01
We present results from high-energy-density (HED) laboratory experiments that explore the contribution of radiative shock waves to the evolving dynamics of the cataclysmic variable (CV) systems in which they reside. CVs can be classified under two main categories, non-magnetic and magnetic. In the process of accretion, both types involve strongly radiating shocks that provide the main source of radiation in the binary systems. This radiation can cause varying structure to develop depending on the optical properties of the material on either side of the shock. The ability of high-intensity lasers to create large energy densities in targets of millimeter-scale volume makes it feasible to create similar radiative shocks in the laboratory. We provide an overview of both CV systems and their connection to the designed and executed laboratory experiments preformed on two laser facilities. Available data and accompanying simulations will likewise be shown. Funded by the NNSA-DS and SC-OFES Joint Prog. in High-Energy-Density Lab. Plasmas, by the Nat. Laser User Facility Prog. in NNSA-DS and by the Predictive Sci. Acad. Alliances Prog. in NNSA-ASC, under grant numbers are DE-FG52-09NA29548, DE-FG52-09NA29034, and DE-FC52-08NA28616.
Exposure to televised alcohol ads and subsequent adolescent alcohol use.
Stacy, Alan W; Zogg, Jennifer B; Unger, Jennifer B; Dent, Clyde W
2004-01-01
To assess the impact of televised alcohol commercials on adolescents' alcohol use. Adolescents completed questionnaires about alcohol commercials and alcohol use in a prospective study. A one standard deviation increase in viewing television programs containing alcohol commercials in seventh grade was associated with an excess risk of beer use (44%), wine/liquor use (34%), and 3-drink episodes (26%) in eighth grade. The strength of associations varied across exposure measures and was most consistent for beer. Although replication is warranted, results showed that exposure was associated with an increased risk of subsequent beer consumption and possibly other consumption variables.
ERIC Educational Resources Information Center
Thomas, Sally
A study was conducted to investigate the impact which certain cognitive styles or structures have in mediating the influence of aggressive television on young boys. The subjects were 143 boys, ranging in age from 5-1/2 to 8-1/2 years, attending elementary school in the Santa Monica area. During the first of two sessions, each child was…
Request for Observations of V405 Peg
NASA Astrophysics Data System (ADS)
Templeton, Matthew R.
2009-12-01
Dr. Axel Schwope (Astrophysikalisches Institut Potsdam) requests time-series monitoring of the magnetic cataclysmic variable V405 Pegasi from 2009 December 28 through 2009 December 30. These observations are requested in support of a planned XMM-Newton observation of V405 Peg on 2009 December 29 beginning at 18:51 UT (JD 2455195.2854) and continuing for 12.5 hours. Observers are asked to provide intensive coverage during the three day window centered on the XMM-Newton observation to provide information on the activity state of V405 Peg, to improve the orbital ephemeris, and to provide optical data that will help constrain the spectral energy distribution of this poorly understood cataclysmic variable. The primary filters for this observation are Johnson B and Cousins I, but all observations will be useful for determining the orbital ephemeris. V405 Peg may show both orbital modulation as well as changes in its activity level. The orbital period is approximately four hours, and observers are asked to obtain at least ten and preferably more data points per cycle in each filter. Please use exposure times that provide S/N of at least 20 in both the comparison and target stars but short exposure times are preferred to detect flickering and other short-timescale variations. Finder charts with sequence may be created using the AAVSO Variable Star Plotter (http://www.aavso.org/vsp). Observations should be submitted to the AAVSO International Database. See full Alert Notice for more details.
ERIC Educational Resources Information Center
Jones, Willis A.
2009-01-01
This study examines the impact of fielding a successful college football team on institutional popularity using a dependent variable (admissions yield) and an independent variable (bowl game television rating) which have been unexamined in previous research on this topic. The findings suggest that college football success is correlated with a…
NASA Astrophysics Data System (ADS)
Jumisko-Pyykkö, Satu; Häkkinen, Jukka
2008-02-01
In the product development of services it is important to adjust mobile video quality according to the quality requirements of potential users. Therefore, a careful participant selection is very important. However, in the literature the details of participant selection are often handled without great detail. This is also reflected in the handling of experimental results, where the impact of psychographic factors on quality is rarely reported. As the user attributes potentially have a large effect to the results, we investigated the role of various psychographical variables on the subjective evaluation of audiovisual video quality in two different experiments. The studied variables were age, gender, education, professionalism, television consumption, experiences of different digital video qualities, and attitude towards technology. The results showed that quality evaluations were affected by almost all background factors. The most significant variables were age, professionalism, knowledge of digital quality features and attitude towards technology. The knowledge of these factors can be exploited in careful participant selection, which will in turn increase the validity of results as the subjective evaluations reflect better the requirements of potential users.
Colak, M Yavuz; Hekimoglu, D; Ersoy, K; Sozen, F; Haberal, M
2010-01-01
The media affects individuals' behaviors, especially by means of news and advertisements. In this study, we evaluated health content of organ donation and transplantation news in the printed media and on television programs for a 1-year period in Turkey. We examined 2449 news items in 230 newspapers and magazines; 1179 news programs on 45 television channels, all concerning organ donation and transplantation. The news obtained from the Media Pursuit Center were transferred to an electronic file to evaluate the format and content of the news. Nine variables were examined about the scope and the formal characteristics of the news: the publication name, its type, the province, the date, the headline, the title length, the presence of a photograph, or its kind, the news size, and the page number. In the content analysis of the news, we also examined 9 variables: the topic, the message of the headline, the property of the words in the title, the identification of photographs in the news, the age, gender of actors in the news, as well as donor or recipient. In a summary, print media and television channels, failed to show sufficient information about organ donation and transplantation. The percentage of news about organ donation and transplantation was small and mostly negative items in the media. On television channels, sufficient place was not given to organ donation and transplantation. The news in printed media and on television channels was not about motivated or altruistic behavior. The pattern of organ donation and transplantation news is important in terms of perception and comment by the public. Furthermore it directly affects the perception of the news by the reader.
Chew, Fiona; Palmer, Sushma; Slonska, Zofia; Subbiah, Kalyani
2002-01-01
This study examined the impact of a health promoting television program series on health knowledge and the key factors of the health belief model (HBM) that have led people to engage in healthy behavior (exercising, losing weight, changing eating habits, and not smoking/quitting smoking). Using data from a posttest comparison field study with 15) viewers and 146 nonviewers in Poland, we found that hierarchical regression analysis showed stronger support for the HBM factors of efficacy, susceptibility, seriousness, and salience in their contribution toward health behavior among television viewers compared with nonviewers. Cues to action variables (including television viewing) and health knowledge boosted efficacy among viewers. Without the advantage of receiving health information from the television series, nonviewers relied on their basic disease fears on one hand, and interest in good health on the other to take steps toward becoming healthier. A health promoting television series can increase health knowledge and enhance health beliefs, which in turn contribute to healthy behaviors.
Associations of Television Content Type and Obesity in Children
Bell, Janice F.
2010-01-01
Objectives. We tested the associations of content types of children's television viewing with subsequent body mass index (BMI) to assess the plausibility of different causal pathways. Methods. We used time-use diary data from the Panel Survey of Income Dynamics to measure television viewing categorized by format and educational and commercial content. Analyses were stratified by age because children younger than 7 years are less able to understand the persuasive intent of advertising. BMI z scores in 2002 were regressed on television viewing, sociodemographic variables, mother's BMI, and BMI in 1997 (for older children only). Results. Among children aged 0 to 6 years in 1997, commercial viewing in 1997 was significantly associated with BMI z scores in 2002 in fully adjusted regressions. Among children older than 6 years, commercial viewing in 2002 was associated with 2002 BMI. These results were robust after adjustment for exercise and eating while watching television. Conclusions. The evidence does not support the contention that television viewing contributes to obesity because it is a sedentary activity. Television advertising, rather than viewing per se, is associated with obesity. PMID:20019313
The Representation of Older People in East Asian Television Advertisements.
Prieler, Michael; Ivanov, Alex; Hagiwara, Shigeru
2017-06-01
In this study, 432 television advertisements from Hong Kong, Japan, and South Korea were analyzed to determine their representations of older people. Findings demonstrate that in East Asian advertisements, older people are highly underrepresented, appear in major roles, mostly alongside younger people, and older men clearly outnumber older women. The other variables investigated (i.e., setting and product categories) led to no conclusive findings for the three societies. In short, our study, employing ethnolinguistic vitality theory to analyze television advertisements, demonstrates how East Asian societies greatly marginalize older people. Potential effects of such representations are discussed using social cognitive theory and cultivation theory.
The Effect of Camera Angle and Image Size on Source Credibility and Interpersonal Attraction.
ERIC Educational Resources Information Center
McCain, Thomas A.; Wakshlag, Jacob J.
The purpose of this study was to examine the effects of two nonverbal visual variables (camera angle and image size) on variables developed in a nonmediated context (source credibility and interpersonal attraction). Camera angle and image size were manipulated in eight video taped television newscasts which were subsequently presented to eight…
Boundary layers in cataclysmic variables: The HEAO-1 X-ray constraints
NASA Technical Reports Server (NTRS)
Jensen, K. A.
1983-01-01
The predictions of the boundary layer model for the X-ray emission from novae are summarized. A discrepancy between observations and theory in the X-ray observations is found. Constraints on the nature of the boundary layers in novae, based on the lack of detections of novae in the HEAO-1 soft X-ray survey are provided. Temperature and column densities for optically thick boundary layers in novae are estimated.
Chandra X-ray Observation of G343.3-0.6
NASA Astrophysics Data System (ADS)
Seguin, Alexander; Glenhaber, Tobit; Fruscione, Antonella; Drake, Jeremy
2018-01-01
The Chandra X-ray Observatory's ACIS-S CCD has detected the Cataclysmic Variable G343.3-0.6 at the coordinates 17:01:28.164, -43:06:12.513. Since its source Nova Sco 1437 was first recorded (Shara et al., 2017 Nature, 548,558), G343.3-0.6 has developed into a "deep eclipsing CV" with an orbital period of 4.4 hours (F. Berdinardi et al., 2017, MNRAS 470,4815).
Using XMM-Newton and Optical Photometry to Figure Out CVs
NASA Astrophysics Data System (ADS)
Szkody, P.; Homer, L.; Henden, A.
2006-06-01
X-ray light curves from XMM-Newton combined with optical data from the satellite and ground-based observers provide distinctive shapes and periodicities that give information on the correct classification of cataclysmic variables. Our recent data on three SDSS sources with strong helium emission are used to identify a highly magnetic system (a polar), the spin of the white dwarf in an intermediate polar, and a typical disk accreting system.
Ngula, Kyalo wa; Mberia, Hellen K; Miller, Ann Neville
2016-01-01
Research in Western nations suggests that parents' involvement in their children's media use can make a difference in how adolescents select, process and respond to sexual television messages. Little or no published research has investigated this issue in sub-Saharan Africa, even though adolescents and young adults remain among the groups at highest risk for HIV transmission. This study investigated the relationship between Kenyan adolescents' level of exposure to sexual television content and their parents' mediation of their television use. A cluster sample of 427 Nairobi public high school students was surveyed regarding parental mediation of their media use and their intake of sexual television content. Co-viewing with opposite sex friends was associated with higher intake of sexual TV content. This relationship was stronger among boarding school students than among day school students. Parental mediation and co-viewing variables predicted three times as much variance among boarding than among day school students.
White, Victoria; Azar, Denise; Faulkner, Agatha; Coomber, Kerri; Durkin, Sarah; Livingston, Michael; Chikritzhs, Tanya; Room, Robin; Wakefield, Melanie
2017-10-01
To determine (i) whether Australian adolescents' exposure to television alcohol advertisements changed between 1999 and 2011 and (ii) examine the association between television alcohol advertising and adolescent drinking behaviours. Cross-sectional surveys conducted every 3 years between 1999 and 2011. Analyses examined associations between advertising exposures and reported drinking. Five Australian major cities. Students aged 12-17 years participating in a triennial nationally representative school-based survey residing in the television advertising markets associated with the major cities (sample size range per survey: 12 644-16 004). Outcome measures were: drinking in the past month, past week and past-week risky drinking (5+ drinks on a day). The key predictor variable was past-month adolescent-directed alcohol advertising Targeted Rating Points (TRPs, a measure of television advertising exposure). Control measures included student-level characteristics, government alcohol-control advertising TRPs, road safety (drink-driving) TRPs and time of survey. Average monthly adolescent alcohol TRPs increased between 1999 (mean = 2371) to 2005 (mean = 2679) (P < 0.01) then decreased between 2005 and 2011: (mean = 880) (P < 0.01). Multi-level logistic regression analyses that adjusted for survey timing, student level factors and alcohol-control advertising variables showed a significant association between past-month alcohol TRPs and past-month drinking [odds ratio (OR) = 1.11, 95% confidence interval (CI) = 1.07-1.15), past-week drinking (OR = 1.10, 95% CI = 1.06-1.14) and past-week risky drinking (OR = 1.15, 95% CI = 1.09-1.22). Past-week risky drinking was associated inversely with road safety TRPs (OR = 0.69, 95% CI = 0.49-0.98). While Australian adolescents' exposure to alcohol advertising on television reduced between 1999 and 2011, higher levels of past-month television alcohol advertising were associated with an increased likelihood of adolescents' drinking. The reduction in television alcohol advertising in Australia in the late 2000s may have played a part in reducing adolescents' drinking prevalence. © 2017 Society for the Study of Addiction.
World Voice Day in news: analysis of reports on the Voice Campaign in Brazil.
Dornelas, Rodrigo; Giannini, Susana Pimentel Pinto; Ferreira, Léslie Piccolotto
2015-01-01
To analyze the television reports on the World Voice Day transmitted by Globo(r) TV. We researched television reports broadcasted by Globo(r) Network in regional television news programs from March 15 to April 20, 2013. For the data analysis, the Document Analysis technique was used. The analyzed variables were the following: location, broadcasting period, duration, interviewed professional, mention of multiprofessional work, orientation to the population, and the interview approach (health promotion or disease prevention). Through statistical analysis, the interview approach was considered the outcome and associated with the other variables. On the regions where there are news programs for the researched TV station, the majority made reports about the Voice Campaign. Among these, we discovered that the five regions of Brazil were contemplated, in the morning/afternoon periods, with medium duration of 5.3 minutes. The presence of the speech-language pathologist was observed in greater numbers of the interviews, as also the emphasis on the importance of a multiprofessional work. Regarding the content presented, the interviewees focused on diseases caused by habits that impair the voice, with orientation to the public about what negatively interferes in the vocal well-being. The approach of the interviews was not, in the majority of times, of the same nature (promoting the vocal well-being or preventing voice disorder), and the interprofessional practice is still seen less frequently as a possible work strategy.
Li, Kaigang; Davison, Kirsten K; Jurkowski, Janine M
2012-01-01
The authors in this cross-sectional study examined mental health and family environmental factors related to a sedentary lifestyle, including lack of leisure-time physical activity and high levels of television viewing, among low-income mothers/female guardians of preschool-aged children. A self-administered questionnaire was completed by 131 mothers in 2010. Primary outcome measures included television viewing time (minutes/day) and leisure-time physical activity (<150 versus ≥150 minutes per week). Independent variables included depressive symptoms, perceived stress, and family functioning. Demographic factors (age, marriage, work status, education, number of children in the household, and race/ethnicity) were examined as potential covariates. Participating women watched television on average 186.1 minutes/day (i.e., >3 hours). Additionally, 36% of women engaged in less than the recommended 150-minute leisure-time physical activity per week. Hierarchical multiple regression analyses indicated that greater depressive symptoms (B = 76.4, p < 0.01) and lower family functioning (B = 33.0, p < 0.05) were independently related to greater television viewing when controlling for other variables. No independent factors were identified for lack of leisure-time physical activity when controlling for other covariates. Findings suggest that health promotion efforts to promote an active lifestyle among low-income women with young children should address mental health and family functioning factors, especially depressive symptoms.
Luo, Kai; Li, Runkui; Wang, Zongshuang; Zhang, Ruiming; Xu, Qun
2017-11-01
There is limited evidence showing the mortality effects of temperature variability (TV) on cardiovascular diseases. The joint effects between TV and air pollutants are also less well-established. This study aims to assess the effect modification of TV-cardiovascular mortality by air pollutants in three Chinese cities (Beijing, Nanjing and Chengdu). Data of daily mortality, air pollutants and meteorological factors from 2008 to 2011 was collected from each city. TV was calculated as the standard deviation of daily maximum and minimum temperatures over exposure days. The city-specific effect estimates of TV on cardiovascular mortality were calculated using a quasi-Poisson regression model, adjusting for potential confounders (e.g., seasonality and temperature). An interaction term of TV and a three-level air pollutants stratum indicator was included in the models. Effect modifications by air pollutants were assessed by comparing the estimates of TV's effect between pollutant stratums and calculating the corresponding 95% confidential interval of the differences. Multivariate meta-analysis was conducted to obtain the pooled estimates. The data showed that TV was associated with increased risk of cardiovascular mortality, especially for longer TV exposure days (0-8 days, TV08). This association was still observed after adjusting for air pollutants on current day or the previous two days. Stronger estimates were observed in females, but no significant difference between males and females was detected, indicating the absence of evidence of effect modification by gender. Estimates of TV-cardiovascular mortality varied across two season periods (warm and cool season) and age groups, but the evidence of effect modification by age and seasons was absent. Regarding the effect modification of TV-cardiovascular mortality association by air pollutants, a significant effect modification was identified for PM 10, but not for NO 2 and SO 2 in the whole population for all TV exposure days. This finding also persisted in subgroups, specifically in females and the elderly. Copyright © 2017 Elsevier Ltd. All rights reserved.
Learning of Information in Television Commercials by Gifted, Normal, and EMR Children.
ERIC Educational Resources Information Center
Hendon, Donald W.; And Others
To learn if differences in age, intelligence, and sex account for differences in children's memory of TV commercials and "degree of insistence" (DI) after viewing them, 54 gifted, 71 normal, and 53 educable mentally retarded children (of both sexes, 7-13 years) were questioned. The mediating influence of the three independent variables on DI was…
A Closed Circuit TV System for the Visually Handicapped and Prospects for Future Research.
ERIC Educational Resources Information Center
Genensky, S. M.; And Others
Some visually handicapped persons have difficulty reading or writing even with the aid of eyeglasses, but could be helped by visual aids which increase image magnification, light intensity or brightness, or some combination of these factors. The system described here uses closed circuit television (CCTV) to provide variable magnification from 1.4x…
Multi-wavelength studies of wind driving cataclysmic variables
NASA Astrophysics Data System (ADS)
Witherick, Dugan Kenneth
This thesis presents several case studies of disc winds from high-state cataclysmic variable stars, based on multi-wavelength time-series spectroscopy. The research presented here primarily focuses on three low-inclination, nova-like systems: RW Sextansis, V592 Cassiopeiae and BZ Camelopardalis. The aim was to derive and compare key spectral line diagnostics of the outflows, spanning a wide range of ionisation and excitation using (new) FUSE, HST, IUE and optical data. Analysis of the far-UV time-series of RW Sex reveals the wind to be highly variable but generally confined to between ~ -1000 and ~ 0 km/s for all ionisation states; no evidence of the wind at red-shifted velocities is found. This wind is modulated on the orbital period of the system and it is argued that the observed variability is due to changes in the blue-shifted absorption rather than a variable velocity emission. The Balmer profiles observed in the optical time-series of V592 Cas were found to be characterised by three components: a broad, shallow absorption trough, a narrow central emission and a blue-shifted absorption from the disc wind. The wind is also found to be modulated on the systems orbital period, although this modulation is slightly out of phase with the Balmer emission radial velocities. The wind of BZ Cam was found to behave very differently to that of RW Sex and V592 Cas. At times, it was seen (in the Balmer lines and some of the He I lines) to be extremely strong and variable but at other times is was seemingly not present; there was no evidence to suggest that it is modulated on the orbital or any other period. This study is an immense source of data on CV disc winds and importantly tries to parameterise three nova-like CVs to understand the similarities and differences between them and their winds.
Li, Kaigang; Davison, Kirsten K.; Jurkowski, Janine M.
2012-01-01
This cross-sectional study examined mental health and family environmental factors related to a sedentary lifestyle, including lack of leisure-time physical activity (LTPA) and high levels of television viewing, among low-income mothers/female guardians of preschool-aged children. A self-administered questionnaire was completed by 131 mothers in 2010. Primary outcome measures included television viewing time (minutes/day) and LTPA (< 150 versus ≥150 minutes per week). Independent variables included depressive symptoms, perceived stress and family functioning. Demographic factors (age, marriage, work status, education, number of children in the household and race/ethnicity) were examined as potential covariates. Participating women watched TV on average 186.1 minutes/day (i.e., >3 hours). Additionally, 36% of women engaged in less than the recommended 150-minute LTPA per week. Hierarchical multiple regression analyses indicated that greater depressive symptoms (B = 76.4, p<.01) and lower family functioning (B = 33.0, p < .05) were independently related to greater television viewing when controlling for other variables. No independent factors were identified for lack of LTPA when controlling for other covariates. Findings suggest that health promotion efforts to promote an active lifestyle among low-income women with young children should address mental health and family functioning factors, especially depressive symptoms. PMID:22860706
Custers, Kathleen; McNallie, Jenna
2016-06-30
Rape affects a large proportion of women in the United States but is one of the most underreported crimes. It is believed that rape myth acceptance contributes to low reporting rates. We tested whether television sports exposure was indirectly related to higher acceptance of rape myth beliefs. An online survey involving 465 undergraduate students showed that viewing TV sports was positively related to hostile sexism, benevolent sexism, and sexual objectification of women. Through these variables, TV sports was indirectly and positively associated with rape myth acceptance. These results suggest that sports programming contributes to the perpetuation of rape myths in society. © The Author(s) 2016.
Accretion Processes in Cosmic Sources
NASA Astrophysics Data System (ADS)
2016-10-01
Accretion is a universal phenomenon that takes place in the vast majority of astrophysical objects. The progress of ground-based and space-borne observational facilities has resulted in the great amount of information on various accreting astrophysical objects, collected within the last decades. The accretion is accompanied by the process of extensive energy release that takes place on the surface of an accreting object and in various gaseous envelopes, accretion disk, jets and other elements of the flow pattern. The results of observations inspired the intensive development of accretion theory, which, in turn, enabled us to study unique properties of accreting objects and physical conditions in the surrounding environment. One of the most interesting outcomes of this intensive study is the fact that accretion processes are, in a sense, self-similar on various spatial scales from planetary systems to galaxies. This fact gives us new opportunities to investigate objects that, by various reasons, are not available for direct study. Cataclysmic variable stars are unique natural laboratories where one can conduct the detailed observational study of accretion processes and accretion disks. This is the main reason why several participants and a few members of the Organizing Committee of the conference "The Golden Age of Cataclysmic Variables and Related Objects - III" (September 7-12, 2015, Palermo, Italy) have decided to hold a special conference, focused on accretion processes, as a branch of that series. Main topics: Young Stellar Objects, protoplanetary discs, exoplanets in binary stars Accretion on white dwarfs (Cataclysmic variables and related objects) Accretion on neutron stars (X-ray Binary Systems and related objects) Accretion on black holes (stellar BH and AGN) The workshop will include a few 35-minute general review talks to introduce the current problems, and 20-minute talks to discuss new experimental and theoretical results. A series of 15-minute talks will discuss the ongoing and planned ground- based and space-based experiments. There will also be some general talks about the future directions of scientific research on cosmic sources. The papers will pass a peer-review process and the workshop proceedings will be edited by Franco Giovannelli & Lola Sabau-Graziati. The location of the workshop is the Ambassador Hotel, located in Saint Petersburg, Russian Federation, a venue that will provide a friendly and collaborative atmosphere.
Multi-wavelength Observations of Accreting Compact Objects
NASA Astrophysics Data System (ADS)
Hernandez Santisteban, Juan Venancio
2016-11-01
The study of compact binaries invokes core astrophysical concepts ranging from stellar and sub-stellar atmospheres and interiors, stellar and binary evolution to physics of accretion. All of these systems are hosts to a compact object a white dwarf, neutron star or black hole ???? which produces a wide variety of exotic and energetic phenomena across the full electromagnetic spectrum. In this thesis, I will make use of multi-wavelength observations ranging from far-ultraviolet to nearinfrared in order to investigate two main topics: a) the late evolution of cataclysmic variables, and b) the accreting state of transitional millisecond pulsars. Firstly, I analyse the Very Large Telescope X-Shooter time-resolved spectroscopy of the short orbital period cataclysmic variable, SDSS J1433+1011, in Chapter 2. The wide wavelength coverage allowed me to perform a detailed characterisation of the system, as well as a direct mass measurement of the brown dwarf companion. I show that the donor in SDSS J1433+1011 successfully transitioned from the stellar to sub-stellar regime, as predicted by evolutionary models. Further light-curve modelling allowed me to show that a low albedo as well as a low heat circulation efficiency is present in the atmosphere of the sub-stellar donor. In Chapter 3, I analyse data from large synoptic surveys, such as SDSS and PTF, to search for the predicted population of dead cataclysmic variables. Following the non-detection of dead CVs, I was able to estimate the space density (?0 < 2?10????5 pc????3) of this hidden population via a Monte Carlo simulation of the Galactic CV population. In Chapter 4, I present Hubble Space Telescope ultraviolet observations of the transitional millisecond pulsar PSR J1023+0038, during its latest accretion state. In combination with optical and near-infrared data, I show that a standard accretion disc does not reach the magnetosphere of the neutron star. Instead, the overall spectrum is consistent with a truncated disc at ? 2:3 ? 109 cm away from the compact object. Furthermore, the ultraviolet data shares remarkable similarities with the only accreting white dwarf in a propeller regime, AE Aqr. Finally, I summarise my results in Chapter 5 and provide future lines of research in accreting compact binaries based on this work.
Two-Color V and R CCD Photometry of the SW Sex-Type Eclipsing Cataclysmic Variable V1315 Aql
NASA Astrophysics Data System (ADS)
Andronov, I. L.; Baklanov, A. V.; Burwitz, V.
2005-08-01
The V-R color index shows a complicated behaviour during the eclipse, being largest at the brightness minimum, but showing asymmetric minima at phases -0.07 and +0.13. The hump at the light curve occurs after the eclipse, contrary to systems with the "hot spot". The phases of minima in V and R are 0.0092(17) and 0.0062(17), respectively, for the mean date JD=2453202.
Doppler Tomography and Photometry of the Cataclysmic Variable 1RXS J064434.5+334451
NASA Astrophysics Data System (ADS)
Echevarria, Juan
2015-08-01
We have obtained simultaneous photometric and spectroscopic observations of the cataclysmic variable 1RXS J064434.5+334451. We have calibrated the spectra for slit losses using the simultaneous photometry. This has been used to construct reliable Doppler images from Hα, Hβ and He II 4686 Å emission lines. We have also analyzed the radial velocity curve of the emission lines to derive its semi-amplitude, and used a co-phasing method to determine the semi-amplitude of the secondary. We have improved the ephemeris of the object based on new photometric eclipse timings to obtain HJD = 2453403.759533 + 0.26937446E. Some eclipses present a clear internal structure which we attribute to a central blob of He II emission surrounding the white dwarf, a finding supported by the Doppler Tomography. This indicates that the system has a large inclination angle i = 78o ± 2. We discuss which radial velocity semi-amplitudes indicator yields a better result for the mass ratio of the system. We derive the masses of the components: M1 = 0.76 ± 0.04 M⊙, M2 = 0.57 ± 0.04 M⊙ and their separation a = 1.92 ± 0.04R⊙ . The Doppler tomography and other observed features in this nova-like system strongly suggests that this is an SW Sex type system.
Follow up Observations of SDSS and CRTS Candidate Cataclysmic Variables
NASA Astrophysics Data System (ADS)
Szkody, Paula; Everett, Mark E.; Howell, Steve B.; Landolt, Arlo U.; Bond, Howard E.; Silva, David R.; Vasquez-Soltero, Stephanie
2014-10-01
We present photometry and spectroscopy of 11 and 35 potential cataclysmic variables, respectively, from the Sloan Digital Sky Survey, the Catalina Real-Time Transient Survey, and vsnet alerts. The photometry results include quasi-periodic oscillations during the decline of V1363 Cyg, nightly accretion changes in the likely Polar (AM Herculis binary) SDSS J1344+20, eclipses in SDSS J2141+05 with an orbital period of 76 ± 2 minutes, and possible eclipses in SDSS J2158+09 at an orbital period near 100 minutes. Time-resolved spectra reveal short orbital periods near 80 minutes for SDSS J0206+20, 85 minutes for SDSS J1502+33, and near 100 minutes for CSS J0015+26, RXS J0150+37, SDSS J1132+62, SDSS J2154+15, and SDSS J2158+09. The prominent He II line and velocity amplitude of SDSS J2154+15 are consistent with a Polar nature for this object, while the absence of this line and a low velocity amplitude argue against this classification for RXS J0150+37. Single spectra of 10 objects were obtained near outburst and the rest near quiescence, confirming the dwarf novae nature of these objects. Based on observations obtained with the Apache Point Observatory (APO) 3.5 m telescope, which is owned and operated by the Astrophysical Research Consortium.
The nova-like cataclysmic variable star: KUV 0859+415
NASA Astrophysics Data System (ADS)
Grauer, Albert D.; Ringwald, F. A.; Wegner, Gary; Liebert, James; Schmidt, Gary D.; Green, Richard F.
1994-07-01
KUV 0859+415 has been found to be an eclipsing, nova-like cataclysmic variable with an orbital period of 3 h and 40 min. We find that it differs from other eclipsing systems of similar period (sometimes called the SW Sex stars) in several important respects. First, the eclipses are shallow, V-shaped dips, suggesting that the inclination angle is relatively low. Also, while the excitation of the emission lines are relatively high (He II comparable to H-beta), they are relatively weak compared to the continuum. The high Balmer lines have broad absorption wings, characteristic of an optically thick accretion disk. Yet there is evidence for a 'hot spot' in the system, which reaches peak brightness near phase 0.9 before the eclipse. Perhaps the most puzzling property of this system is that the H-alpha emission line radial velocity leads rather than lags the expected position for the location of the accretion disk. We present briefly a phenomenological model for the system which has a hot spot located at the normal location for the accretion stream to first impact the disk and is the source of excess optical continuum. However, the velocity curve of the emission lines requires us to conclude that the bulk of this radiation forms on the opposite side of the disk. This also explains the fact that the peak equivalent widths of H-alpha occur at phases 0.4-0.5.
NASA Astrophysics Data System (ADS)
Belloni, Diogo; Zorotovic, Mónica; Schreiber, Matthias R.; Leigh, Nathan W. C.; Giersz, Mirek; Askar, Abbas
2017-06-01
In this third of a series of papers related to cataclysmic variables (CVs) and related objects, we analyse the population of CVs in a set of 12 globular cluster models evolved with the MOCCA Monte Carlo code, for two initial binary populations (IBPs), two choices of common-envelope phase (CEP) parameters, and three different models for the evolution of CVs and the treatment of angular momentum loss. When more realistic models and parameters are considered, we find that present-day cluster CV duty cycles are extremely low (≲0.1 per cent) that makes their detection during outbursts rather difficult. Additionally, the IBP plays a significant role in shaping the CV population properties, and models that follow the Kroupa IBP are less affected by enhanced angular momentum loss. We also predict from our simulations that CVs formed dynamically in the past few Gyr (massive CVs) correspond to bright CVs (as expected) and that faint CVs formed several Gyr ago (dynamically or not) represent the overwhelming majority. Regarding the CV formation rate, we rule out the notion that it is similar irrespective of the cluster properties. Finally, we discuss the differences in the present-day CV properties related to the IBPs, the initial cluster conditions, the CEP parameters, formation channels, the CV evolution models and the angular momentum loss treatments.
Two bodies with high eccentricity around the cataclysmic variable QS Vir
NASA Astrophysics Data System (ADS)
Almeida, Leonardo A.; Jablonski, Francisco
2011-11-01
QS Vir is an eclipsing cataclysmic variable with 3.618 hrs orbital period. This system has the interesting characteristics that it does not show mass transfer between the components through the L1 Lagrangian point and shows a complex orbital period variation history. Qian et al. (2010) associated the orbital period variations to the presence of a giant planet in the system plus angular momentum loss via magnetic braking. Parsons et al. (2010) obtained new eclipse timings and observed that the orbital period variations associated to a hypothetical giant planet disagree with their measurements and concluded that the decrease in orbital period is part of a cyclic variation with period ~16 yrs. In this work, we present 28 new eclipse timings of QS Vir and suggest that the orbital period variations can be explained by a model with two circumbinary bodies. The best fitting gives the lower limit to the masses M1 sin(i) ~ 0.0086 M⊙ and M2 sin(i) ~ 0.054 M⊙ orbital periods P1 ~ 14.4 yrs and P2 ~ 16.99 yrs, and eccentricities e1 ~ 0.62 and e2~0.92 for the two external bodies. Under the assumption of coplanarity among the two external bodies and the inner binary, we obtain a giant planet with ~0.009 M⊙ and a brown dwarf with ~ 0.056 M⊙ around the eclipsing binary QS Vir.
Double cyclic variations in orbital period of the eclipsing cataclysmic variable EX Dra
NASA Astrophysics Data System (ADS)
Han, Zhong-tao; Qian, Sheng-bang; Voloshina, Irina; Zhu, Li-Ying
2017-06-01
EX Dra is a long-period eclipsing dwarf nova with ˜2-3 mag amplitude outbursts. This star has been monitored photometrically from November, 2009 to March, 2016 and 29 new mid-eclipse times were obtained. By using new data together with the published data, the best fit to the O-C curve indicate that the orbital period of EX Dra have an upward parabolic change while undergoing double-cyclic variations with the periods of 21.4 and 3.99 years, respectively. The upward parabolic change reveals a long-term increase at a rate of \\dot{P}= {+7.46}×10^{-11} s s^{-1}. The evolutionary theory of cataclysmic variables (CVs) predicts that, as a CV evolves, the orbital period should be decreasing rather than increasing. Secular increase can be explained as the mass transfer between the secondary and primary or may be just an observed part of a longer cyclic change. Most plausible explanation for the double-cyclic variations is a pair of light travel-time effect via the presence of two companions. Their masses are determined to be MAsin i'A=29.3(±0.6) M_{Jup} and MBsin i'B=50.8(±0.2) M_{Jup}. When the two companions are coplanar to the orbital plane of the central eclipsing pair, their masses would match to brown dwarfs.
X-ray Spectral Analysis of the Cataclysmic Variable LS Peg using XMM-Newton Observatory Data
NASA Astrophysics Data System (ADS)
Talebpour Sheshvan, N.; Nabizadeh, A.; Balman, S.
2017-10-01
LS Peg is a Cataclysmic Variable (CV) suggested as Intermediate Polar (IP) because of similar properties to those observed in IP systems. We used archival XMM-Newton observation of LS Peg in order to study the X-ray characteristics of the system. We show LS Peg light curves in several different energy bands, and discuss about orbital modulations and power spectral analysis. Unlike the previous spectral analysis of the EPIC-MOS data by fitting a hot optically thin plasma emission model with a single temperature, we simultaneously fit EPIC spectrum (pn+MOS) using a composite model of absorption (tbabs) along with two different partial covering absorbers plus a multi-temperature plasma emission component in XSPEC. In addition, we find a Gaussian emission line at 6.4 keV. For LS Peg the maximum temperature of the plasma distribution is found to be ˜ 17.8 keV with a luminosity of ˜ 7.4×10^{32}erg s^{-1} translating to an accretion rate of ˜ 1.7×10 ^{-10} M_{⊙} yr^{-1}. We present spectra for orbital minimum and orbital maximum. In addition, we use SWIFT observations of the source in order to make a comparison. We elaborate on the geometry of accretion and absorption in the X-ray emitting region with articulation on the magnetic nature.
An Almost Complete Radio Survey of Magnetic Cataclysmic Variables
NASA Astrophysics Data System (ADS)
Dieck, Christopher A.; Everett Barrett, Paul; Beasley, Anthony J.; Pal Singh, Kulinder; Boboltz, David A.; Godon, Patrick; Mason, Paul A.
2016-01-01
This poster presents the results of a radio survey using the Jansky Very Large Array (JVLA) of 129 Magnetic Cataclysmic Variables (MCVs) north of declination -35 deg. 103 hours of observations were performed during the JVLA observing sessions 2013B and 2015A, when the array was mostly in its highest spatial-resolution configurations (i.e., A and B). Most targets were observed twice for 2-5 minutes at each of three frequencies (C, X, and K-bands), although a few targets were also observed at a fourth frequency (Q-band). 22 of the 129 MCVS were detected at one or more frequencies. Of these 22 detections, 15 are new. This number nearly triples the number of MCVs that are known radio sources. Most detections are at the C and X-band frequencies, although three sources were detected at the K-band frequency. One of the K-band frequency detections is the known rapidly-rotating radio source AE Aqr, while the other two are the polars, AI Tri and ST LMi. Of the 22 detected sources, two-thirds are polars (15) and all are believed to be nearby (<200 pc). Except for a few stronger sources, most detections are in the range of 100-200 µJy, which at a distance of 150 pc corresponds roughly to a luminosity of 2x1024 erg/s at the X-band frequency. The results of this survey are encouraging in that more MCVs are likely to be detected as the time on-source increases, since the flux from MCVs is highly variable.
Cataclysmic variables to be monitored for HST observations
NASA Astrophysics Data System (ADS)
Waagen, Elizabeth O.
2012-09-01
Drs. Boris Gaensicke (Warwick University), Joseph Patterson (Columbia University, Center for Backyard Astrophysics), and Arne Henden (AAVSO), on behalf of a consortium of 16 astronomers, requested the help of AAVSO observers in monitoring the ~40 cataclysmic variables in support of Hubble Space Telescope observations in the coming months. The HST COS (Cosmic Origins Spectrograph) will be carrying out far-ultraviolet spectroscopy of ~40 CVs sequentially, with the aim to measure the temperatures, atmospheric compositions, rotation rates, and eventually masses of their white dwarfs. The primary purpose of the monitoring is to know whether each target is in quiescence immediately prior to the observation window; if it is in outburst it will be too bright for the HST instrumentation. Based on the information supplied by the AAVSO, the HST scheduling team will make the decision (usually) the evening before the scheduled observing time as to whether to go forward with the HST observations. For CCD observers, simultaneous photometry [shortly before, during, and after the HST observations] would be ideal. B filter would be best for a light curve, although for the magnitude estimates, V would be best. Finder charts may be created using the AAVSO Variable Star Plotter (http://www.aavso.org/vsp). Observations should be submitted to the AAVSO International Database. If the target is seen in outburst, please contact the AAVSO immediately and post a message to the Observations and Campaigns & Observations Reports forum (http://www.aavso.org/forum). This campaign will run the better part of a year or longer. See full Alert Notice for more details and list of objects.
On the formation of TW Crv optical radiation
NASA Astrophysics Data System (ADS)
Shimansky, V. V.; Mitrofanova, A. A.; Borisov, N. V.; Fabrika, S. N.; Galeev, A. I.
2016-10-01
We present the analysis of the optical radiation of the young pre-cataclysmic variable TW Crv. Spectroscopic and photometric observations were obtained at the SAO RAS 6-m BTA telescope and at the Russian-Turkish RTT-150 telescope. The light curves of the system posses nearly sinusoidal shapes with the amplitudes of Δ m > 0.m7, what is typical for young pre-cataclysmic variables with sdO-subdwarfs and orbit inclinations of less than 45◦. The optical spectrum contains dominant radiation of the hot subdwarf with the HI and He II absorption lines and strong emission lines, which are formed in the atmosphere of the secondary owing to the reflection effects. Radial velocities of the cool star were measured by analyzing the λλ 4630-4650 Å Bowen blend, which for the first time allowed to determine the component masses. A numerical simulation of the light curves and spectra of TW Crv, obtaining a complete set of systems fundamental parameters was carried out. The hot star parameters prompt its belonging to the sdOsubdwarf class at the stage of transition to the cooling white dwarf sequence. The absence of its observable planetary nebula is caused by a long-lasting evolution of the system after the common envelope state. The secondary component has a luminosity excess, which is typical for other young sdO-subdwarf precataclysmic variables. Its position on the " age-luminosity excess" diagram points at the accuracy of the obtained set of TW Crv fundamental parameters and at the similarity of its evolutionary and physical conditions with that of other BE UMa-type objects.
Effects of a Cancer Prevention Advertisement on Beliefs and Knowledge about Cancer Prevention.
Kye, Su Yeon; Yoo, Jisu; Lee, Min Hee; Jun, Jae Kwan
2015-01-01
Outcome-expectation beliefs and knowledge may ultimately influence behavior for cancer prevention. The aims of this study were to measure changes in knowledge and beliefs about cancer prevention before and after viewing a television advertisement and identify the factors affecting receptivity to its messages. A one-group pretest-posttest design was used in this study of 1,000 individuals aged 20 to 65 years who were recruited online in November 2014. The outcome variables included cancer prevention beliefs based on the Health Belief Model (five items) and knowledge about risk factors for cancer (seven items). Perceived susceptibility, perceived benefits, and self-efficacy increased significantly and their perceived severity and perceived barriers decreased significantly, after participants viewed the television advertisement. Correct responses to questions about risk factors also increased significantly, except for smoking. The main factors affecting changes in the outcome variables were age, interest in cancer prevention, social network, satisfaction with the ad, and pretest scores. Television advertisements with positive frameworks can be an efficient channel of improving beliefs and knowledge about cancer prevention in a short period. The continuous development of intervention materials that consider the demographics, needs, and satisfaction of the target group will be necessary for future studies.
Fogel, Joshua; King, Kahlil
2014-08-01
Reality television programming is a popular type of television programming, and features shows about cosmetic surgery. Social media such as Facebook and Twitter are increasingly popular methods of sharing information. The authors surveyed college students to determine among those watching reality television cosmetic surgery programs whether perceived realism or social media use was associated with attitudes toward cosmetic surgery. Participants (n=126) were surveyed about their reality television cosmetic surgery program viewing habits, their perception of the realism of reality television programming, and social media topics of Twitter and Facebook. Outcome variables were the Acceptance of Cosmetic Surgery Scales of social, intrapersonal, and consider. Perceived realism was significantly associated with increased scores on the Acceptance of Cosmetic Surgery Scale subscales of social (p=0.004), intrapersonal (p=0.03), and consider (p=0.03). Following a character from a reality television program on Twitter was significantly associated with increased social scores (p=0.04). There was no significant association of Facebook behavior with attitudes toward cosmetic surgery. Cosmetic plastic surgeons may benefit by advertising their services on cosmetic surgery reality television programs. These reality television programs portray cosmetic surgery in a positive manner, and viewers with increased perceived realism will be a potential receptive audience toward such advertising. Also, advertising cosmetic surgery services on Twitter feeds that discuss cosmetic surgery reality television programs would be potentially beneficial.
NASA Astrophysics Data System (ADS)
Valencic, Lynne; Arcus Team
2018-01-01
Arcus is a free-flying MIDEX satellite selected for Phase A and planned to launch in 2023. Its bandpass (~12-50 Å), high resolution (R > 2500 between 22-25 Å), and effective area (450 cm2 between 22-25 Å) make it ideal for studying numerous systems after its baseline mission concludes in 2026. For instance, hot star winds show strong but poorly understood variable spectra, as do cataclysmic variables and super-soft sources that may be the progenitors of Type Ia supernovae, and the nature of the ISM is still not well known. Arcus will also allow observations of small extended sources like supernova remnants and planetary nebulae.
On learning science and pseudoscience from prime-time television programming
NASA Astrophysics Data System (ADS)
Whittle, Christopher Henry
The purpose of the present dissertation is to determine whether the viewing of two particular prime-time television programs, ER and The X-Files, increases viewer knowledge of science and to identify factors that may influence learning from entertainment television programming. Viewer knowledge of scientific dialogue from two science-based prime-time television programs, ER, a serial drama in a hospital emergency room and The X-Files, a drama about two Federal Bureau of Investigation agents who pursue alleged extraterrestrial life and paranormal activity, is studied. Level of viewing, education level, science education level, experiential factors, level of parasocial interaction, and demographic characteristics are assessed as independent variables affecting learning from entertainment television viewing. The present research involved a nine-month long content analysis of target television program dialogue and data collection from an Internet-based survey questionnaire posted to target program-specific on-line "chat" groups. The present study demonstrated that entertainment television program viewers incidentally learn science from entertainment television program dialogue. The more they watch, the more they learn. Viewing a pseudoscientific fictional television program does necessarily influence viewer beliefs in pseudoscience. Higher levels of formal science study are reflected in more science learning and less learning of pseudoscience from entertainment television program viewing. Pseudoscience learning from entertainment television programming is significantly related to experience with paranormal phenomena, higher levels of viewer parasocial interaction, and specifically, higher levels of cognitive parasocial interaction. In summary, the greater a viewer's understanding of science the more they learn when they watch their favorite science-based prime-time television programs. Viewers of pseudoscience-based prime-time television programming with higher levels of paranormal experiences and parasocial interaction demonstrate cognitive interest in and learning of their favorite television program characters ideas and beliefs. What television viewers learn from television is related to what they bring to the viewing experience. Television viewers are always learning, even when their intentions are to simply relax and watch the tube.
Alcohol in the mass media and drinking by adolescents: a longitudinal study.
Connolly, G M; Casswell, S; Zhang, J F; Silva, P A
1994-10-01
Data from a longitudinal study carried out in Dunedin, New Zealand, were used to investigate associations between alcohol consumption at age 18 years and alcohol-related mass media communications recalled at ages 13 and 15 years. The respondents' recall of alcohol-related mass media material were categorized as: commercial alcohol advertising, alcohol moderation messages or the portrayal of alcohol in entertainment. An additional media variable was the number of hours spent watching television. Non-media variables, such as peer approval of drinking, living situation and occupation (all at age 18 years) were also included in the analyses. The period between the interviews at ages 13 and 15 years saw an increase in the broadcast of commercial alcohol advertisements on television in New Zealand and this was reflected in an increase in the proportion of the mass media material recalled which was categorized as commercial advertising. At age 15 years television advertising, mostly for beer companies, was the predominant material recalled. No relationships were found between the commercial advertising and wine and spirits consumption, among either men or women, but young women who had watched more hours of television drank more wine/spirits. Among women there were two unexpected negative relationships between recall of alcohol in the media at age 13 years and beer consumption. However, among men there was a consistent positive relationship such that those who had recalled more alcohol advertisements at age 15 years drank larger quantities of beer at age 18 years.
Backyard Telescopes Watch an Expanding Binary
NASA Astrophysics Data System (ADS)
Kohler, Susanna
2018-01-01
What can you do with a team of people armed with backyard telescopes and a decade of patience? Test how binary star systems evolve under Einsteins general theory of relativity!Unusual VariablesCataclysmic variables irregularly brightening binary stars consisting of an accreting white dwarf and a donor star are a favorite target among amateur astronomers: theyre detectable even with small telescopes, and theres a lot we can learn about stellar astrophysics by observing them, if were patient.Diagram of a cataclysmic variable. In an AM CVn, the donor is most likely a white dwarf as well, or a low-mass helium star. [Philip D. Hall]Among the large family of cataclysmic variables is one unusual type: the extremely short-period AM Canum Venaticorum (AM CVn) stars. These rare variables (only 40 are known) are unique in having spectra dominated by helium, suggesting that they contain little or no hydrogen. Because of this, scientists have speculated that the donor stars in these systems are either white dwarfs themselves or very low-mass helium stars.Why study AM CVn stars? Because their unusual configuration allows us to predict the behavior of their orbital evolution. According to the general theory of relativity, the two components of an AM CVn will spiral closer and closer as the system loses angular momentum to gravitational-wave emission. Eventually they will get so close that the low-mass companion star overflows its Roche lobe, beginning mass transfer to the white dwarf. At this point, the orbital evolution will reverse and the binary orbit will expand, increasing its period.CBA member Enrique de Miguel, lead author on the study, with his backyard telescope in Huelva, Spain. [Enrique de Miguel]Backyard Astronomy Hard at WorkMeasuring the evolution of an AM CVns orbital period is the best way to confirm this model, but this is no simple task! To observe this evolution, we first need a system with a period that can be very precisely measured best achieved with an eclipsing binary system. Then the system must be observed regularly over a very long period of time.Though such a feat is challenging, a team of astronomers has done precisely this. The Center for Backyard Astrophysics (CBA) a group of primarily amateur astronomers located around the world has collectively observed the AM CVn star system ES Ceti using seven different telescopes over more than a decade. In total, they now have measurements of ES Cetis period spanning 20012017. Now, in a publication led by Enrique de Miguel (CBA-Huelva and University of Huelva, Spain), the group details the outcomes of their patience.Testing the ModelThis OC diagram of the timings of minimum light relative to a test ephemeris demonstrates that ES Cetis orbital period is steadily increasing over time. [de Miguel et al. 2017]De Miguel and collaborators find that ES Cetis 10.3-minute orbital period has indeed increased over time as predicted by the model at a relatively rapid rate: the timescale for change, described by P/(dP/dt), is 10 million years. This outcome is consistent with the hypothesis that the mass transfer and binary evolution of such systems is driven by gravitational radiation marking one of the first such demonstrations with a cataclysmic variable.Whats next for ES Ceti? Systems such as this one will make for interesting targets for the Laser Interferometer Space Antenna (LISA; planned for a 2034 launch). The gravitational radiation emitted by AM CVns like ES Ceti should be strong enough and in the right frequency range to be detected by LISA, providing another test of our models for how these star systems evolve.CitationEnrique de Miguel et al 2018 ApJ 852 19. doi:10.3847/1538-4357/aa9ed6
Associations between content types of early media exposure and subsequent attentional problems.
Zimmerman, Frederick J; Christakis, Dimitri A
2007-11-01
Television and video/DVD viewing among very young children has become both pervasive and heavy. Previous studies have reported an association between early media exposure and problems with attention regulation but did not have data on the content type that children watched. We tested the hypothesis that early television viewing of 3 content types is associated with subsequent attentional problems. The 3 different content types are educational, nonviolent entertainment, and violent entertainment. Participants were children in a nationally representative sample collected in 1997 and reassessed in 2002. The analysis was a logistic regression of a high score on a validated parent-reported measure of attentional problems, regressed on early television exposure by content and several important sociodemographic control variables. Viewing of educational television before age 3 was not associated with attentional problems 5 years later. However, viewing of either violent or non-violent entertainment television before age 3 was significantly associated with subsequent attentional problems, and the magnitude of the association was large. Viewing of any content type at ages 4 to 5 was not associated with subsequent problems. The association between early television viewing and subsequent attentional problems is specific to noneducational viewing and to viewing before age 3.
Sharing resources, coordinating response : deploying and operating incident management systems
DOT National Transportation Integrated Search
1999-01-05
This brochure describes how cost-effective incident management technologies can be useful in handling traffic congestion. Embedded sensors, closed circuit television cameras, and variable message signs are examples of existing technologies that can b...
IVHS Institutional Issues And Case Studies: Advantage I-75 Case Study
DOT National Transportation Integrated Search
1999-01-01
This brochure describes how cost-effective incident management technologies can be in handling traffic congestion. Embedded sensors, closed circuit television cameras, and variable message signs are examples of existing technologies that can be enhan...
Boundary layers in cataclysmic variables - The HEAO 1 X-ray constraints
NASA Technical Reports Server (NTRS)
Jensen, K. A.
1984-01-01
The predictions of the boundary layer model for the X-ray emission from novae are summarized. A discrepancy between observations and theory in the X-ray observations is found. Constraints on the nature of the boundary layers in novae, based on the lack of detections of novae in the HEAO-1 soft X-ray survey are provided. Temperature and column densities for optically thick boundary layers in novae are estimated. Previously announced in STAR as N84-13046
Magnetic Fields in Interacting Binaries
NASA Astrophysics Data System (ADS)
Briggs, G.; Ferrario, L.; Tout, C. A.; Wickramasinghe, D. T.
2018-01-01
Wickramasinghe et al. (2014) and Briggs et al. (2015) have proposed that the strong magnetic fields observed in some single white dwarfs (MWDs) are formed by an α—Ω dynamo driven by differential rotation when two stars, the more massive one with a degenerate core, merge during common envelope (CE) evolution (Ferrario et al., 2015b). We synthesise a population of binaries to investigate if fields in the magnetic cataclysmic variables (MCVs) may also originate during stellar interaction in the CE phase.
NASA Technical Reports Server (NTRS)
Holt, S. S.; Mushotzky, R. F.
1979-01-01
An overview of X-ray astronomical spectroscopy in general is presented and results obtained by HEAO 1 and 2 as well as earlier spacecraft are examined. Particular emphasis is given to the spectra of supernova remnants; galactic binary X-ray sources, cataclysmic variables, bulges, pulsars, and stars; the active nuclei of Seyfert 1 galaxy, BL Lac, and quasars; the diffuse X-ray background; and galactic clusters.
Verzeletti, Chiara; Maes, Lea; Santinello, Massimo; Vereecken, Carine A
2010-06-01
The number of studies among adolescents that focus on several lifestyle behaviours and family rules as determinant of soft drink consumption are limited. The aim of this study is to investigate the associations between daily soft drink consumption, food-related lifestyles and family rules in adolescence. The data are part of the Health Behavior in School-aged Children (HBSC) cross-sectional survey. Adolescents between 11 and 16 years of age were included, resulting in a final sample of 14 407 adolescents representative of Belgium Flanders (N = 7904) and the Veneto Region of Italy (N = 6503). Binary logistic regression was used to test the association between soft drink consumption and food-related lifestyle (breakfast habits, family meals, snacking, meals in fast food restaurants and television viewing) and family rules (restriction and obligation rules) by region and gender. Each independent variable is significantly associated with daily soft drink consumption, despite some sub-groups exceptions. When we entered all the variables into the same statistical model, the positive association with daily soft drink consumption remained significant for frequent meals in fast food restaurants, television variables and low restriction rules. Breakfast during weekdays, evening meal with parents and obligation rules remained significant only in specific sub-groups and not the entire sample. Finally, the association with breakfast with parents and during the weekend disappeared. These findings suggest that considering gender and cultural differences, involving parents and limiting adolescents' exposure to television would increase the effectiveness of interventions aimed to reduce soft drink consumption in adolescence.
An intervention to reduce television viewing by preschool children.
Dennison, Barbara A; Russo, Theresa J; Burdick, Patrick A; Jenkins, Paul L
2004-02-01
Television viewing has been associated with increased violence in play and higher rates of obesity. Although there are interventions to reduce television viewing by school-aged children, there are none for younger children. To develop and evaluate an intervention to reduce television viewing by preschool children. Randomized controlled trial conducted in 16 preschool and/or day care centers in rural upstate New York. Children aged 2.6 through 5.5 years. Children attending intervention centers received a 7-session program designed to reduce television viewing as part of a health promotion curriculum, whereas children attending the control centers received a safety and injury prevention program. Change in parent-reported child television/video viewing and measured growth variables. Before the intervention, the intervention and control groups viewed 11.9 and 14.0 h/wk of television/videos, respectively. Afterward, children in the intervention group decreased their television/video viewing 3.1 h/wk, whereas children in the control group increased their viewing by 1.6 h/wk, for an adjusted difference between the groups of -4.7 h/wk (95% confidence interval, -8.4 to -1.0 h/wk; P =.02). The percentage of children watching television/videos more than 2 h/d also decreased significantly from 33% to 18% among the intervention group, compared with an increase of 41% to 47% among the control group, for a difference of -21.5% (95% confidence interval, -42.5% to -0.5%; P =.046). There were no statistically significant differences in children's growth between groups. This study is the first to show that a preschool-based intervention can lead to reductions in young children's television/video viewing. Further research is needed to determine the long-term effects associated with reductions in young children's television viewing.
Vulnerability to the impact of temperature variability on mortality in 31 major Chinese cities.
Yang, Jun; Zhou, Maigeng; Li, Mengmeng; Liu, Xiaobo; Yin, Peng; Sun, Qinghua; Wang, Jun; Wu, Haixia; Wang, Boguang; Liu, Qiyong
2018-08-01
Few studies have analyzed the health effects of temperature variability (TV) accounting for both interday and intraday variations in ambient temperature. In this study, TV was defined as the standard deviations of the daily minimum and maximum temperature during different exposure days. Distributed lag non-linear Poisson regression model was used to examine the city-specific effect of TV on mortality in 31 Chinese municipalities and provincial capital cities. The national estimate was pooled through a meta-analysis based on the restricted maximum likelihood estimation. To assess effect modification on TV-mortality association by individual characteristics, stratified analyses were further fitted. Potential effect modification by city characteristics was performed through a meta-regression analysis. In total, 259 million permanent residents and 4,481,090 non-accidental deaths were covered in this study. The effect estimates of TV on mortality were generally increased by longer exposure days. A 1 °C increase in TV at 0-7 days' exposure was associated with a 0.60% (95% CI: 0.25-0.94%), 0.65% (0.24-1.05%), 0.82% (0.29-1.36%), 0.86% (0.42-1.31%), 0.98% (0.57-1.39%) and 0.54% (-0.11-1.20%) increase in non-accidental, cardiovascular, IHD, stroke, respiratory and COPD mortalities, respectively. Those with lower levels of educational attainment were significantly susceptible to TV. Cities with dense population, higher mean temperatures, and relative humidity and lower diurnal temperature ranges also had higher mortality risks caused by TV. This study demonstrated that TV had considerable health effects. An early warning system to alert residents about large temperature variations is recommended, which may have a significant impact on the community awareness and public health. Copyright © 2018 Elsevier Ltd. All rights reserved.
te Velde, Saskia J; Singh, Amika; Chinapaw, Mai; De Bourdeaudhuij, Ilse; Jan, Natasa; Kovacs, Eva; Bere, Elling; Vik, Froydis N; Bringolf-Isler, Bettina; Manios, Yannis; Moreno, Luis; Brug, Johannes
2014-01-01
To design interventions that target energy balance-related behaviours, knowledge of primary schoolchildren's perceptions regarding soft drink intake, fruit juice intake, breakfast consumption, TV viewing and physical activity (PA) is essential. The current study describes personal beliefs and attitudes, home- and friend-related variables regarding these behaviours across Europe. Cross-sectional study in which personal, family and friend -related variables were assessed by validated questionnaires, and dichotomized as favourable versus unfavourable answers. Logistic regression analyses were conducted to estimate proportions of children giving unfavourable answers and test between-country differences. A survey in eight European countries. A total of 7903 10-12 year old primary schoolchildren. A majority of the children reported unfavourable attitudes, preferences and subjective norms regarding soft drink, fruit juice intake and TV viewing accompanied with high availability and accessibility at home. Few children reported unfavourable attitudes and preferences regarding breakfast consumption and PA. Many children reported unfavourable health beliefs regarding breakfast consumption and TV viewing. Substantial differences between countries were observed, especially for variables regarding soft drink intake, breakfast consumption and TV viewing. The surveyed children demonstrated favourable attitudes to some healthy behaviours (PA, breakfast intake) as well as to some unhealthy behaviours (soft drink consumption, TV viewing). Additionally, many children across Europe have personal beliefs and are exposed to social environments that are not supportive to engagement in healthy behaviours. Moreover, the large differences in personal, family and friend-related variables across Europe argue for implementing different strategies in the different European countries.
Detection of Accretion X-Rays from QS Vir: Cataclysmic or a Lot of Hot Air?
NASA Astrophysics Data System (ADS)
Matranga, Marco; Drake, Jeremy J.; Kashyap, Vinay; Steeghs, Danny
2012-03-01
An XMM-Newton observation of the nearby "pre-cataclysmic" short-period (P orb = 3.62 hr) binary QS Vir (EC 13471-1258) revealed regular narrow X-ray eclipses when the white dwarf passed behind its M2-4 dwarf companion. The X-ray emission provides a clear signature of mass transfer and accretion onto the white dwarf. The low-resolution XMM-Newton EPIC spectra are consistent with a cooling flow model and indicate an accretion rate of \\dot{M} = 1.7 \\times 10^{-13} \\,M_\\odot yr-1. At 48 pc distant, QS Vir is then the second nearest accreting cataclysmic variable known, with one of the lowest accretion rates found to date for a non-magnetic system. To feed this accretion through a wind would require a wind mass-loss rate of \\dot{M}\\sim 2\\times 10^{-12}\\,M_\\odot yr-1 if the accretion efficiency is of the order of 10%. Consideration of likely mass-loss rates for M dwarfs suggests this is improbably high and pure wind accretion unlikely. A lack of accretion disk signatures also presents some difficulties for direct Roche lobe overflow. We speculate that QS Vir is on the verge of Roche lobe overflow, and that the observed mass transfer could be supplemented by upward chromospheric flows on the M dwarf, analogous to spicules and mottles on the Sun, that escape the Roche surface to be subsequently swept up into the white dwarf Roche lobe. If so, QS Vir would be in a rare evolutionary phase lasting only a million years. The X-ray luminosity of the M dwarf estimated during primary eclipse is LX = 3 × 1028 erg s-1, which is consistent with that of rapidly rotating "saturated" K and M dwarfs.
Structured Sparse Principal Components Analysis With the TV-Elastic Net Penalty.
de Pierrefeu, Amicie; Lofstedt, Tommy; Hadj-Selem, Fouad; Dubois, Mathieu; Jardri, Renaud; Fovet, Thomas; Ciuciu, Philippe; Frouin, Vincent; Duchesnay, Edouard
2018-02-01
Principal component analysis (PCA) is an exploratory tool widely used in data analysis to uncover the dominant patterns of variability within a population. Despite its ability to represent a data set in a low-dimensional space, PCA's interpretability remains limited. Indeed, the components produced by PCA are often noisy or exhibit no visually meaningful patterns. Furthermore, the fact that the components are usually non-sparse may also impede interpretation, unless arbitrary thresholding is applied. However, in neuroimaging, it is essential to uncover clinically interpretable phenotypic markers that would account for the main variability in the brain images of a population. Recently, some alternatives to the standard PCA approach, such as sparse PCA (SPCA), have been proposed, their aim being to limit the density of the components. Nonetheless, sparsity alone does not entirely solve the interpretability problem in neuroimaging, since it may yield scattered and unstable components. We hypothesized that the incorporation of prior information regarding the structure of the data may lead to improved relevance and interpretability of brain patterns. We therefore present a simple extension of the popular PCA framework that adds structured sparsity penalties on the loading vectors in order to identify the few stable regions in the brain images that capture most of the variability. Such structured sparsity can be obtained by combining, e.g., and total variation (TV) penalties, where the TV regularization encodes information on the underlying structure of the data. This paper presents the structured SPCA (denoted SPCA-TV) optimization framework and its resolution. We demonstrate SPCA-TV's effectiveness and versatility on three different data sets. It can be applied to any kind of structured data, such as, e.g., -dimensional array images or meshes of cortical surfaces. The gains of SPCA-TV over unstructured approaches (such as SPCA and ElasticNet PCA) or structured approach (such as GraphNet PCA) are significant, since SPCA-TV reveals the variability within a data set in the form of intelligible brain patterns that are easier to interpret and more stable across different samples.
Buijzen, Moniek; Schuurman, Joris; Bomhof, Elise
2008-01-01
In a diary-survey study in 234 households with children aged 4-12 years, we investigated the associations between children's exposure to food advertising and their consumption of (a) advertised food brands, (b) advertised energy-dense food product categories, and (c) food products overall. Relations were examined using multiple hierarchical regression analysis, while controlling for various child (i.e., age, sex, television viewing time) and family variables (i.e., family income and consumption-related communication styles). Results showed that children's exposure to food advertising was significantly related to their consumption of advertised brands (beta=.21) and energy-dense product categories (beta=.19). The relation between advertising exposure and overall food consumption only held in lower-income families (beta=.19). In addition, consumption-related family communication was an important moderator of the relations between advertising and the food consumption variables. Socio-oriented family communication (i.e., striving for harmony and conformity) was particularly successful in reducing these relations. In conclusion, consistent with communication theories predicting spill-over effects of advertising, the impact of television food advertising exceeded the advertised brand and generalized to more generic unhealthy consumption patterns. Theoretical and societal consequences, as well as the important role of the family are discussed.
Howe, Anna S; Heath, Anne-Louise M; Lawrence, Julie; Galland, Barbara C; Gray, Andrew R; Taylor, Barry J; Sayers, Rachel; Taylor, Rachael W
2017-01-01
Despite the American Academy of Pediatrics (AAP) recommending that electronic media be avoided in children under two years of age, screen use is common in infants and toddlers. The aims of this study were to determine how parenting style, infant temperament, and family type are associated with television viewing in two-year-old children. Participants were from the Prevention of Overweight in Infancy (POI) randomized controlled trial (n = 802) (Dunedin, New Zealand). Demographic information was collected at baseline (late pregnancy), and television and other screen time assessed by questionnaire at 24 months of age. Parenting style (Parenting Practices Questionnaire), infant temperament (Colorado Childhood Temperament Inventory), and family type (7 categories) were reported by both parents. Data were available for 487 participants (61% of the original participants). Median television viewing was relatively low at 21 minutes per day, or 30 minutes in those watching television (82%). Children who watched television played with mobile phones (12% of children) or iPads/tablets (22% of children) more frequently than children who did not (6% of children). In terms of parenting style, children of more authoritarian mothers (β = 17, 95% CI: 6-27 minutes), more authoritarian partners (β = 14, 95% CI: 2-26 minutes), or more permissive mothers (β = 10, 95% CI: 3-17 minutes) watched significantly more television. No significant relationships were observed between child temperament and time watching television after adjustment for confounding variables. Children from "active" families (as rated by partners) watched 29 minutes less television each day (P = 0.002). Parenting style and family type were associated with television viewing time in young children, whereas child temperament was not.
Heath, Anne-Louise M.; Lawrence, Julie; Galland, Barbara C.; Taylor, Barry J.; Sayers, Rachel
2017-01-01
Objectives Despite the American Academy of Pediatrics (AAP) recommending that electronic media be avoided in children under two years of age, screen use is common in infants and toddlers. The aims of this study were to determine how parenting style, infant temperament, and family type are associated with television viewing in two-year-old children. Study design Participants were from the Prevention of Overweight in Infancy (POI) randomized controlled trial (n = 802) (Dunedin, New Zealand). Demographic information was collected at baseline (late pregnancy), and television and other screen time assessed by questionnaire at 24 months of age. Parenting style (Parenting Practices Questionnaire), infant temperament (Colorado Childhood Temperament Inventory), and family type (7 categories) were reported by both parents. Results Data were available for 487 participants (61% of the original participants). Median television viewing was relatively low at 21 minutes per day, or 30 minutes in those watching television (82%). Children who watched television played with mobile phones (12% of children) or iPads/tablets (22% of children) more frequently than children who did not (6% of children). In terms of parenting style, children of more authoritarian mothers (β = 17, 95% CI: 6–27 minutes), more authoritarian partners (β = 14, 95% CI: 2–26 minutes), or more permissive mothers (β = 10, 95% CI: 3–17 minutes) watched significantly more television. No significant relationships were observed between child temperament and time watching television after adjustment for confounding variables. Children from “active” families (as rated by partners) watched 29 minutes less television each day (P = 0.002). Conclusions Parenting style and family type were associated with television viewing time in young children, whereas child temperament was not. PMID:29261676
NASA Astrophysics Data System (ADS)
Rose, S. C.
2017-06-01
(Abstract only) Magnetic cataclysmic variable stars have brightness variations that repeat with each revolution of the two stars about the center of mass of the system. However, in the case of QQ Vulpecula, this brightness variation pattern changes in the long term. This study makes use of two decades worth of data from the Roboscope Telescope as well as data from the American Association of Variable Star Observers (AAVSO) database to examine the long-term evolution of QQ Vul's phase curves. Nightly observations using the Maria Mitchell Association Vestal and Loines Observatory supplemented this analysis by clarifying short-term brightness variation. The long-term data was divided into four commonly observed behavioral types ranging from a double peaked curve of 15.5 magnitude to a 15.0 magnitude curve that had a primary minimum and a slow, linear rise in brightness in place of the secondary minimum. The nightly data kept within the confines of these categories, though the secondary minimum in the nightly data never vanished. No periodicity was found in the long-term variations. The model often invoked to explain the double peaked curve consists of single pole accretion in which a partial self-eclipse causes the secondary minimum and cyclotron beaming causes the primary minimum. However, the long-term variation may indicate a changing accretion rate, which may manifest itself in changes to the shape, size, or location of the accretion spot on the white dwarf such that it lessens or removes the secondary minimum. This project was supported by the NSF REU grant AST-1358980, the Massachusetts Space Grant, and the Nantucket Maria Mitchell Association.
Long-term Accretion Variations of the Magnetic Cataclysmic Variable Star QQ Vulpecula
NASA Astrophysics Data System (ADS)
Cooper Rose, Sanaea; Kafka, Stella; Jorgenson, Regina; Carr, Derrick; Childs, Francesca; Christenson, Holly; Karim, Md. Tanveer; Konchady, Tarini; Walker, Gary E.; Honeycutt, R. K.
2017-01-01
Magnetic cataclysmic variable stars have brightness variations that repeat with each revolution of the two stars about the center of mass of the system. However, in the case of QQ Vulpecula (QQ Vul), this brightness variation pattern changes in the long term. This study makes use of two decades worth of data from the Roboscope Telescope as well as data from the American Association of Variable Star Observers (AAVSO) database to examine the long-term evolution of QQ Vul’s phase curves. Nightly observations using the Maria Mitchell Association's Vestal and Loines Observatories supplemented this analysis by clarifying short-term brightness variation. The long-term data was divided into four commonly observed behavioral types ranging from a double peaked curve of ~15.5 magnitude to a ~15.0 magnitude curve that had a primary minimum and a slow, linear rise in brightness in place of the secondary minimum. The nightly data kept within the confines of these categories, though the secondary minimum in the nightly data never vanished. No periodicity was found in the long-term variations. The model often invoked to explain the double peaked curve consists of single pole accretion in which a partial self-eclipse causes the secondary minimum and cyclotron beaming causes the primary minimum. However, the long-term variation may indicate a changing accretion rate, which may manifest itself in changes to the shape, size, or location of the accretion spot on the white dwarf such that it lessens or removes the secondary minimum. This project was supported by the NSF REU grant AST-1358980, the Massachusetts Space Grant, and the Nantucket Maria Mitchell Association.
Infrared observations of AE Aquarii
NASA Technical Reports Server (NTRS)
Tanzi, E. G.; Chincarini, G.; Tarenghi, M.
1981-01-01
Broadband infrared observations of the cataclysmic variable AE Aquarii are reported. The observations were obtained in the J, H, K and L filters with the InSb photometer attached to the 1-m telescope of the European Southern Observatory. The infrared energy distribution observed from 0.35 to 3.5 microns for phase 0.5 suggests a spectral type of K5 V for the secondary and a distance to the system of approximately 70 pc if an absolute magnitude of 7.3 is assumed. Monitoring of the flux at 2.2 microns reveals a variability with an amplitude of approximately 0.3 magnitude over one third of the orbital period, the nature of which is under investigation.
The new eclipsing magnetic binary system E 1114 + 182
NASA Technical Reports Server (NTRS)
Biermann, P.; Schmidt, G. D.; Liebert, J.; Tapia, S.; Strittmatter, P. A.; West, S.; Stockman, H. S.; Kuehr, H.; Lamb, D. Q.
1985-01-01
A comprehensive analysis of E 1114 + 182, the first eclipsing AM Herculis binary system and the shortest-period eclipsing cataclysmic variable known, is presented. The time-resolved X-ray observations which led to the system's recognition as an AM Her system with a roughly 90 minute orbital period are reported. The current optical photometric and polarimetric ephemeris and a description of the system's phase-modulated properties are given. The detailed photometric eclipse profile and the highly variable spectroscopic behavior are addressed. This information is used to determine systemic parameters and derive new information on the line emission regions. The data put severe constraints on current torque models for keeping the binary and white dwarf rotation in phase.
NASA Astrophysics Data System (ADS)
Espinoza, Fernando
2009-10-01
Mass media, particularly television, influence public conceptions and attitudes toward learning science. The discovery of an original method that does not rely on self-reported viewing habits to measure the impact of television on students' performance in science arose from a study of a unit on electricity in a Physics course. In determining the number of television sets at home and the number of hours of operation, data emerged that allowed an investigation of associations between each of these variables and student performance in physics. A negative impact on performance was found in its consistent decrease as both the number of sets and the time the sets are on increase. These results provide dramatic independent confirmation of the negative impact of television viewing on achievement determined through meta-analysis of many studies, and are also consistent with those in the literature at large, particularly from the Third International Mathematics and Science Study, and the National Assessment of Educational Progress. Furthermore, the totally `blind' participation of the subjects lends a degree of authenticity rarely found in a classically designed study. The findings impact scientific literacy, since performance in science and conceptions of science and scientists, are all inextricably linked.
A televised entertainment-education drama to promote positive discussion about organ donation.
Khalil, Georges E; Rintamaki, Lance S
2014-04-01
This article investigates pathways between the exposure to an entertainment-education (E-E) television drama called Three Rivers and positive discussion of organ donation among viewers of the drama in the United States. A cross-sectional survey was conducted using an online advertising for a period of one week. Survey participants included 1325 adults living in the United States, who had viewed the first episode of Three Rivers on television. Data were collected on recall of events in the storyline, perceived entertainment value, perceived accuracy of the presented health information, rejection of organ donation myths and positive discussion of organ donation and the storyline. Covariates were registration for organ donation, membership to the donation or transplant community and demographic variables. Results show that viewers with high recall of the storyline were more likely to reject myths about organ donation and engage in pro-donation discussions with others. Perceived entertainment value and perceived accuracy acted as mediators in such relationships. The insertion of accurate health information in television drama may be effective in promoting positive discussions about organ donation and myth rejection. Recall of events from the televised E-E drama Three Rivers, entertainment value and accuracy perception were associated with positive discussion.
Relationships between use of television during meals and children's food consumption patterns.
Coon, K A; Goldberg, J; Rogers, B L; Tucker, K L
2001-01-01
We examined relationships between the presence of television during meals and children's food consumption patterns to test whether children's overall food consumption patterns, including foods not normally advertised, vary systematically with the extent to which television is part of normal mealtime routines. Ninety-one parent-child pairs from suburbs adjacent to Washington, DC, recruited via advertisements and word of mouth, participated. Children were in the fourth, fifth, or sixth grades. Socioeconomic data and information on television use were collected during survey interviews. Three nonconsecutive 24-hour dietary recalls, conducted with each child, were used to construct nutrient and food intake outcome variables. Independent sample t tests were used to compare mean food and nutrient intakes of children from families in which the television was usually on during 2 or more meals (n = 41) to those of children from families in which the television was either never on or only on during one meal (n = 50). Multiple linear regression models, controlling for socioeconomic factors and other covariates, were used to test strength of associations between television and children's consumption of food groups and nutrients. Children from families with high television use derived, on average, 6% more of their total daily energy intake from meats; 5% more from pizza, salty snacks, and soda; and nearly 5% less of their energy intake from fruits, vegetables, and juices than did children from families with low television use. Associations between television and children's consumption of food groups remained statistically significant in multiple linear regression models that controlled for socioeconomic factors and other covariates. Children from high television families derived less of their total energy from carbohydrate and consumed twice as much caffeine as children from low television families. There continued to be a significant association between television and children's consumption of caffeine when these relationships were tested in multiple linear regression models. The dietary patterns of children from families in which television viewing is a normal part of meal routines may include fewer fruits and vegetables and more pizzas, snack foods, and sodas than the dietary patterns of children from families in which television viewing and eating are separate activities.
Krakatoa Erupts!: Using a Historic Cataclysm to Teach Modern Science
ERIC Educational Resources Information Center
Clary, Renee; Wandersee, James
2011-01-01
Through integration of geology, biology, chemistry, and the history of science, the historic Krakatoa eruption offers a unique portal for student inquiry in the classroom. Students are inherently fascinated by natural disasters, and modern comparisons to the Krakatoa cataclysm are as close as the day's news. This article uses the historic Krakatoa…
A Longitudinal Study of Consumer Socialization.
ERIC Educational Resources Information Center
Moschis, George P.; Moore, Roy L.
A study examined the effects of factors (including television, family, peers, age, and socioeconomic status) on consumer socialization, the process by which individuals develop consumption-related cognitions and behaviors. The specific criterion variables studied included consumer affairs knowledge, puffery filtering, consumer finance management,…
Unusual ``Stunted'' Outbursts in Old Novae and Nova-Like Cataclysmic Variables
NASA Astrophysics Data System (ADS)
Honeycutt, R. K.; Robertson, J. W.; Turner, G. W.
1998-06-01
Outbursts averaging 0.6 mag in amplitude and 10 days in width are described in five old novae and nova-like cataclysmic variables: UU Aqr, Q Cyg, CP Lac, X Ser, and RW Sex. These stars are thought to be high mass transfer rate systems for which the accretion disk is expected to be stable against the thermal instability responsible for dwarf nova outbursts. The widths and spacings of these events are similar to those of dwarf nova eruptions, but the amplitudes are significantly smaller, or ``stunted.'' The outbursts are sometimes accompanied by dips. These dips have amplitudes that are similar to the outbursts' but have shapes that scatter significantly more than the shapes of the outbursts. The outbursts and dips sometimes occur as pairs and are sometimes isolated. We are not able at this time to determine a single common mechanism for this behavior, or even to conclude that some mechanisms are preferred. Rather, we characterize these phenomena with regard to outburst shapes and frequency of occurrence and explore a range of possible causes, including truncated disks, mass transfer modulations, and Z Camelopardalis type behavior. Arguments are assembled for and against such possible mechanisms, and key observations are suggested. It appears unlikely that accretion disk instabilities are the single common cause of these phenomena, and we are left with either a combination of accretion disk and mass transfer events or a situation in which mass transfer events are somehow responsible for all these varied behaviors.
The Anomalous Accretion Disk of the Cataclysmic Variable RW Sextantis
NASA Astrophysics Data System (ADS)
Linnell, Albert P.; Godon, P.; Hubeny, I.; Sion, E. M.; Szkody, P.
2011-01-01
The standard model for stable Cataclysmic Variable (CV) accretion disks (Frank, King and Raine 1992) derives an explicit analytic expression for the disk effective temperature as function of radial distance from the white dwarf (WD). That model specifies that the effective temperature, Teff(R), varies with R as ()0.25, where () represents a combination of parameters including R, the mass transfer rate M(dot), and other parameters. It is well known that fits of standard model synthetic spectra to observed CV spectra find almost no instances of agreement. We have derived a generalized expression for the radial temperature gradient, which preserves the total disk luminosity as function of M(dot) but permits a different exponent from the theoretical value of 0.25, and have applied it to RW Sex (Linnell et al.,2010,ApJ, 719,271). We find an excellent fit to observed FUSE and IUE spectra for an exponent of 0.125, curiously close to 1/2 the theoretical value. Our annulus synthetic spectra, combined to represent the accretion disk, were produced with program TLUSTY, were non-LTE and included H, He, C, Mg, Al, Si, and Fe as explicit ions. We illustrate our results with a plot showing the failure to fit RW Sex for a range of M(dot) values, our model fit to the observations, and a chi2 plot showing the selection of the exponent 0.125 as the best fit for the M(dot) range shown. (For the final model parameters see the paper cited.)
Chen, Nien-Tsu Nancy
2015-07-01
Major health behavior change models tend to consider health decisions as primarily resulting from a systematic appraisal of relevant beliefs, such as the perceived benefits and risks of a pharmacological intervention. Drawing on research from the disciplines of risk management, communication, and psychology, this study proposed the inclusion of a heuristic route in established theory and tested the direction of influence between heuristic and systematic process variables. Affect and social trust were included as key heuristics in the proposed dual-mode framework of health decision making. Furthermore, exposure to health-related coverage on television was considered potentially influential over both heuristic and systematic process variables. To test this framework, data were collected from a national probability sample of 584 adults in the United States in 2012 regarding their decision to vaccinate against a hypothetical avian flu. The results provided some support for the bidirectional influence between heuristic and systematic processing. Affect toward flu vaccination and trust in the Food and Drug Administration were found to be powerful predictors of vaccination intention, enhancing intention both directly and indirectly via certain systematic process variables. The direction of influence between perceived susceptibility and severity, on the one hand, and affect, on the other, is less clear, suggesting the need for further research. Contrary to the opinion of media critics, exposure to televised health coverage was negatively associated with the perceived risks of vaccination. Results from this study carry theoretical and practical implications, and applying this model to the acceptance of different health interventions constitutes an area for future inquiries. © 2015 Society for Risk Analysis.
Prevalence and causes of low birth weight in India.
Bharati, P; Pal, M; Bandyopadhyay, M; Bhakta, A; Chakraborty, S; Bharati, P
2011-12-01
The aims of the study are (i) to understand inter-zone and interstate variation of low birth weight (LBW) and (ii) to determine the key variables to reduce LBW in India. Using the latest National Family Health Survey (NFHS) data of 2005-06 which showed the percentage distribution of LBW infants, ANOVA and post-hoc test were performed to determine the spatial variation of birth weight. The covariates which influence LBW fell into three categories: (i) social variables which included location, mother's education, religion, access of mothers to newspapers, television and family structure; (ii) economic variable namely, the wealth index, and (iii) biological variables which consisted of sex of the children, birth order, and mother's body mass index (BMI). Three models of Logistic regression were carried out to examine the influence of the combinations of these direct and indirect factors. In India, nearly 20% of new borns have LBW. Males have less frequency of LBW than females. The North-east zone has the lowest prevalence of LBW while the north zone has the highest. Mother's education, access to TV and nuclear family, and intake of iron tablets are the most important socio-economic influences on the determination of birth weight in India. It is essential to provide proper diet and nutritional care of mothers during pregnancy. Increased education of mothers through programmes in TV and newspapers articles have significant roles to play in reducing LBW in India.
Lingineni, Ravi K; Biswas, Swati; Ahmad, Naveed; Jackson, Bradford E; Bae, Sejong; Singh, Karan P
2012-05-14
The purpose of this study was to investigate the association between Attention Deficit/Hyperactivity Disorder (ADHD) and various factors using a representative sample of US children in a comprehensive manner. This includes variables that have not been previously studied such as watching TV/playing video games, computer usage, family member's smoking, and participation in sports. This was a cross-sectional study of 68,634 children, 5-17 years old, from the National Survey of Children's Health (NSCH, 2007-2008). We performed bivariate and multivariate logistic regression analyses with ADHD classification as the response variable and the following explanatory variables: sex, race, depression, anxiety, body mass index, healthcare coverage, family structure, socio-economic status, family members' smoking status, education, computer usage, watching television (TV)/playing video games, participation in sports, and participation in clubs/organizations. Approximately 10% of the sample was classified as having ADHD. We found depression, anxiety, healthcare coverage, and male sex of child to have increased odds of being diagnosed with ADHD. One of the salient features of this study was observing a significant association between ADHD and variables such as TV usage, participation in sports, two-parent family structure, and family members' smoking status. Obesity was not found to be significantly associated with ADHD, contrary to some previous studies. The current study uncovered several factors associated with ADHD at the national level, including some that have not been studied earlier in such a setting. However, we caution that due to the cross-sectional and observational nature of the data, a cause and effect relationship between ADHD and the associated factors can not be deduced from this study. Future research on ADHD should take into consideration these factors, preferably through a longitudinal study design.
Children's violent television viewing: are parents monitoring?
Cheng, Tina L; Brenner, Ruth A; Wright, Joseph L; Sachs, Hari Cheryl; Moyer, Patricia; Rao, Malla R
2004-07-01
Violent media exposure has been associated with aggressive behavior, and it has been suggested that child health professionals counsel families on limiting exposure. Effective violence prevention counseling requires an understanding of norms regarding parental attitudes, practices, and influencing factors. Both theories of reasoned action and planned behavior emphasize that subjective norms and attitudes affect people's perceptions and intended behavior. Few data exist on violent television viewing and monitoring from a cross-section of families. By understanding the spectrum of parental attitudes, community-sensitive interventions for violence prevention can be developed. The objective of this study was to assess attitudes about and monitoring of violent television viewing from the perspective of parents. An anonymous self-report assisted survey was administered to a convenience sample of parents/guardians who visited child health providers at 3 sites: an urban children's hospital clinic, an urban managed care clinic, and a suburban private practice. The parent questionnaire included questions on child-rearing attitudes and practices and sociodemographic information. A total of 1004 adults who accompanied children for health visits were recruited for the study; 922 surveys were completed (participation rate: 92%). A total of 830 (90%) respondents were parents and had complete child data. Of the 830 respondents, 677 had questions on television viewing included in the survey and were the focus of this analysis. Seventy-five percent of families reported that their youngest child watched television. Of these, 53% reported always limiting violent television viewing, although 73% believed that their children viewed television violence at least 1 time a week. Among television viewers, 81% reported usually or always limiting viewing of sexual content on television and 45% reported usually or always watching television with their youngest child. Among children who watched television, parents reported that they spent an average of 2.6 hours per day watching television. Limitation of television violence was associated with female parents and younger children. There was variability in attitudes and practices regarding television violence viewing and monitoring among parents. Attitudes and practices varied on the basis of the age of the child and the gender of the parent.
Rosen, Zohn; Johnson, Gretchen
2013-01-01
Background Television viewing is associated with an increased risk of mortality, which could be caused by a sedentary lifestyle, the content of television programming (e.g., cigarette product placement or stress-inducing content), or both. Methods We examined the relationship between self-reported hours of television viewing and mortality risk over 30 years in a representative sample of the American adult population using the 2008 General Social Survey-National Death Index dataset. We also explored the intervening variable effect of various emotional states (e.g., happiness) and beliefs (e.g., trust in government) of the relationship between television viewing and mortality. Results We find that for each additional hour of viewing, mortality risks increased 4%. Given the mean duration of television viewing in our sample, this amounted to about 1.2 years of life expectancy in the US. This association was tempered by a number of potential psychosocial mediators, including self-reported measures of happiness, social capital, or confidence in institutions. While none of these were clinically significant, the combined mediation power was statistically significant (p < 0.001). Conclusions Television viewing among healthy adults is correlated with premature mortality in a nationally-representative sample of US adults, and this association may be partially mediated by programming content related to beliefs or affective states. However, this mediation effect is the result of many small changes in psychosocial states rather than large effects from a few factors. PMID:23683712
1RXS J173021.5-055933: a cataclysmic variable with a fast-spinning magnetic white dwarf
NASA Astrophysics Data System (ADS)
de Martino, D.; Matt, G.; Mukai, K.; Bonnet-Bidaud, J.-M.; Falanga, M.; Gänsicke, B. T.; Haberl, F.; Marsh, T. R.; Mouchet, M.; Littlefair, S. P.; Dhillon, V.
2008-04-01
Aims:We present the first X-ray observations with the XMM-Newton and INTEGRAL satellites of the recently discovered cataclysmic variable 1RXS J173021.5-055933, together with simultaneous UV and coordinated optical photometry aiming at characterising its broad-band temporal and spectral properties and classifying this system as a magnetic one. Methods: We performed a timing analysis of the X-ray, UV, and optical light curves to identify and to study the energy dependence of the fast 128 s pulsation over a wide energy range. X-ray spectral analysis in the broad 0.2-100 keV X-ray range was performed to characterise the peculiar emission properties of this source. Results: We find that the X-ray light curve is dominated by the spin period of the accreting white dwarf in contrast to the far-UV range, which turns out to be unmodulated at a 3σ level. Near-UV and optical pulses are instead detected at twice the spin frequency. We identify the contributions from two accreting poles that imply a moderately inclined dipole field allowing, one pole to dominate at energies at least up to 10 keV, and a secondary that instead is negligible above 5 keV. X-ray spectral analysis reveals the presence of multiple emission components consisting of optically thin plasma with temperatures ranging from 0.17 keV to 60 keV and a hot blackbody at ~90 eV. The spectrum is also strongly affected by peculiar absorption components consisting of two high-density (~3 × 1021~cm-2 and 2 × 1023~cm-2) intervening columns, plus a warm absorber. The last is detected from an OVII absorption edge at 0.74 keV, which suggests that photoionization of pre-shock material is also occurring in this system. Conclusions: The observed properties indicate that the accretor in 1RXS J173021.5-055933 is a white dwarf with a likely weak magnetic field, thus confirming this cataclysmic variable as an intermediate polar (IP) with one of the most extreme spin-to-orbit period ratios. This system also joins the small group of IPs showing a soft X-ray reprocessed component, suggesting that this characteristics is not uncommon in these systems. Based on observations obtained with XMM-Newton and INTEGRAL, ESA science missions with instruments and contributions directly funded by ESA Member States and NASA.
Hours of television viewing and sleep duration in children: a multicenter birth cohort study.
Marinelli, Marcella; Sunyer, Jordi; Alvarez-Pedrerol, Mar; Iñiguez, Carmen; Torrent, Maties; Vioque, Jesús; Turner, Michelle C; Julvez, Jordi
2014-05-01
This study used longitudinal data to examine potential associations between hours of television viewing and sleep duration in children. To examine the association between hours of television viewing and sleep duration in preschool and school-aged children. Longitudinal, multicenter study among birth cohorts in Menorca, Sabadell, and Valencia from the Spanish Infancia y Medio Ambiente (environment and childhood) project. The study sample included 1713 children (468 from Menorca, 560 from Sabadell, and 685 from Valencia). Parent-reported child television viewing duration measured in hours per day at 2 and 4 years of age in Sabadell and Valencia and at 6 and 9 years of age in Menorca. Parent-reported child sleep duration measured in hours per day at 2 and 4 years of age in Sabadell and Valencia and at 6 and 9 years of age in Menorca. In cross-sectional analysis, children with longer periods of television viewing reported at baseline (≥ 1.5 hours per day) had shorter sleep duration. Longitudinally, children with reported increases in television viewing duration over time (from <1.5 to ≥ 1.5 hours per day) had a reduction in sleep duration at follow-up visits. Results were similar when examining television viewing duration as a continuous variable, with each 1 hour per day of increased viewing decreasing sleep duration at follow-up visits (β = -0.11; 95% CI, -0.18 to -0.05). Associations were similar when television viewing duration was assessed during weekends and after adjusting for potential intermediate factors (child executive function and attention-deficit/hyperactivity disorder symptoms) and confounders (child physical activity level, parental mental health status, maternal IQ, and maternal marital status). Children spending longer periods watching television had shorter sleep duration. Changes in television viewing duration were inversely associated with changes in sleep duration in longitudinal analysis. Parents should consider avoiding long periods of daily television exposure among preschool and school-aged children.
A Nationwide Experimental Multi-Gigabit Network
2003-03-01
television and cinema , and to real- time interactive teleconferencing. There is another variable which affects this happy growth in network bandwidth and...render large scientific data sets with interactive frame rates on the desktop or in an immersive virtual reality ( VR ) environment. In our design, we
Discovery of deep eclipses in the cataclysmic variable IPHAS J051814.33+294113.0
NASA Astrophysics Data System (ADS)
Kozhevnikov, V. P.
2018-06-01
Performing the photometric observations of the cataclysmic variable IPHAS J051814.33+294113.0, we discovered very deep eclipses. The observations were obtained over 14 nights, had a total duration of 56 hours and covered one year. The large time span, during which we observed the eclipses, allowed us to measure the orbital period in IPHAS J051814.33+294113.0 with high precision, P_{orb}=0.20603098± 0.00000025 d. The prominent parts of the eclipses lasted 0.1± 0.01 phases or 30± 3 min. The depth of the eclipses was variable in the range 1.8-2.9 mag. The average eclipse depth was equal to 2.42± 0.06 mag. The prominent parts of the eclipses revealed a smooth and symmetric shape. We derived the eclipse ephemeris, which, according to the precision of the orbital period, has a formal validity time of 500 years. This ephemeris can be useful for future investigations of the long-term period changes. During the latter four observational nights in 2017 January, we observed the sharp brightness decrease of IPHAS J051814.33+294113.0 by 2.3 mag. This brightness decrease imitated the end of the dwarf nova outburst. However, the long-term light curve of IPHAS J051814.33+294113.0 obtained in the course of the Catalina Sky Survey during 8 years showed no dwarf nova outbursts. From this we conclude that IPHAS J051814.33+294113.0 is a novalike variable. Moreover, the sharp brightness decrease, which we observed in IPHAS J051814.33+294113.0, suggests that this novalike variable belongs to the VY Scl-subtype. Due to very deep eclipses, IPHAS J051814.33+294113.0 is suitable to study the accretion disc structure using eclipse mapping techniques. Because this novalike variable has the long orbital period, it is of interest to determine the masses of the stellar components from radial velocity measurements. Then, our precise eclipse ephemeris can be useful to the phasing of spectroscopic data.
Polley, Diana C; Spicer, Maria T; Knight, Ada P; Hartley, Ben L
2005-02-01
Study objectives were to describe overweight in Native-American and African-American three-generation families and to examine relationships among the individual variables of body mass index (BMI), television hours, and activity levels. Forty-four Native-American and 40 African-American families were recruited from 10 sites through community contacts at health, senior, community, and tribal centers. Ninety percent of parents and grandparents had BMIs above 25.0. Forty-two percent of African-American and 61% of Native-American children had a BMI above the 85th percentile. More than 35% of total energy was from fat. Significant correlations were observed between parent and child BMI and television hours, grandparent and child BMI, and grandparent and parent activity with child television hours. Sedentary caretakers facilitate more television viewing and less activity in children. Dietetics professionals should plan family-friendly daily physical activities, like walking, and diets lower in fat, sugar, and total energy, with higher intakes of fresh fruits and vegetables, whole grains, and low-fat dairy products for children and caretakers.
Serial position effects in recall of television commercials.
Terry, W Scott
2005-04-01
Does the position of a television commercial in a block of commercials determine how well it will be recalled? The findings of naturalistic studies can be affected by uncontrolled presentation, viewing, and retention variables. In the present article, college students viewed lists of 15 commercials in a laboratory simulation and recalled the product brand names. In an immediate test, the first commercials in a list were well recalled (a primacy effect), as were the last items (a recency effect), in comparison with the recall of middle items. In an end-of-session test, the primacy effect persisted, but the recency effect disappeared. Embedding lists within a television program again produced better recall of the first items during end-of-session tests of recall and recognition. These results offered convergent validity for the naturalistic studies of commercial memory, and they supported the usefulness of combining laboratory and field methods to answer questions about everyday memory.
Identification of an educational production function for diverse technologies
NASA Technical Reports Server (NTRS)
Mcclung, R. L.
1977-01-01
Production function analysis used to estimate the cost effectiveness of three alternative technologies in higher education: traditional instruction, instructional television, and computer-assisted instruction is presented. Criteria and selection of a functional form are outlined and a general discussion of variable selection and measurement is presented.
NASA Technical Reports Server (NTRS)
Groumpos, P. P.; Dimitriadis, B. D.; Whyte, W.
1984-01-01
Protection ratios, the ratio of wanted-to-unwanted signal power at the receiver input, for acceptable picture quality were experimentally evaluated for four different still pictures. The variation of carrier-to-interference, C/I, with picture impairment grade is investigated when different noise levels are present. Results are presented which show the relationship between the impairment grade and the C/I ratio for FM/TV co-channel systems under variable S/N conditions.
Nobile, Leda; Lamanna, Irene; Fontana, Vito; Donadello, Katia; Dell'anna, Antonio Maria; Creteur, Jacques; Vincent, Jean-Louis; Pappalardo, Federico; Taccone, Fabio Silvio
2015-11-01
Spontaneous alterations in temperature homeostasis after cardiac arrest (CA) are associated with worse outcome. However, it remains unclear the prognostic role of temperature variability (TV) during cooling procedures. We hypothesized that low TV during targeted temperature management (TTM) would be associated with a favourable neurological outcome after CA. We reviewed data from all comatose patients after in-hospital or out-of-hospital CA admitted to our Department of Intensive Care between December 2006 and January 2014 who underwent TTM (32-34°C) and survived at least 24h. We collected demographic data, CA characteristics, intensive care unit (ICU) survival and neurological outcome at three months (favourable neurological outcome was defined as cerebral performance category 1-2). TV was expressed using the standard deviation (SD) of all temperature measurements during hypothermia; high TV was defined as an SD >1°C. Of the 301 patients admitted over the study period, 72 patients were excluded and a total of 229 patients were studied; 88 had a favourable neurological outcome. The median temperature on ICU admission was 35.8 [34.9-36.9]°C and the median time to hypothermia (body temperature <34°C), was 4 [3-7] h. Median TV was 0.9 [0.6-1.0]°C and 57 patients (25%) had high TV. In multivariable logistic regression, witnessed CA, ventricular fibrillation/tachycardia and previous neurological disease were independent risk factors for high TV. Younger age, bystander cardiopulmonary resuscitation, shorter time to return of spontaneous circulation, cardiac origin of arrest, shockable rhythm and longer time to target temperature were independent predictors of favourable neurological outcome, but TV was not. Among comatose survivors treated with TTM after CA, 25% of patients had high TV; however, this was not associated with a worse neurologic outcome. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
PX Andromedae and the SW Sextantis phenomenon
NASA Technical Reports Server (NTRS)
Hellier, Coel; Robinson, E. L.
1994-01-01
We show that the emission-line peculiarities of PX And and other SW Sex stars can be explained by an accretion stream which overflows the initial impact with the accretion disk and continues to a later reimpact. The overflowing stream is seen projected against a brighter disk and produces the 'phase 0.5 absorption' features. Emission from the reimpact site produces the high-velocity line wings which alternate from red to blue on the orbital cycle. We conclude that substantial disk overflow is the property distinguishing SW Sex stars from other cataclysmic variables.
S193: another non-eclipsing SW Sex star
NASA Astrophysics Data System (ADS)
Martínez-Pais, I. G.; Rodríguez-Gil, P.; Casares, J.
1999-05-01
We present time-resolved optical spectroscopy of the cataclysmic variable S193. The emission lines are remarkably similar to those of V795 Her and exhibit high-velocity S-waves and complex absorptions that are modulated with the orbital period. Evidence for transient anomalous spectral features is seen during the first two nights of our run. We propose that S193 and V795 Her are non-eclipsing SW Sex stars. Finally, we show that the `disc overflow' model fails to explain the Balmer line orbital behaviour in these low-inclination systems.
The HEAO-A2 soft X-ray survey of cataclysmic variable stars - EX Hydrae during optical quiescence
NASA Technical Reports Server (NTRS)
Cordova, F. A.; Riegler, G. R.
1979-01-01
Results are reported for HEAO A2 soft X-ray (below 2 keV) scanning observations of the southern dwarf nova EX Hya. An X-ray light curve is presented which shows no apparent orbital modulation. The best-fitting spectral parameters are derived for the source, and the observations are compared with the spectral behavior of the dwarf nova SS Cyg during optical quiescence. The results are discussed in terms of models for X-ray production by accreting white dwarfs.
Investigation relative to the Roentgen Satellite (ROSAT)
NASA Technical Reports Server (NTRS)
Elvis, Martin S.; Primini, Francis A.; Fabbiano, Guiseppina; Harris, Daniel E.; Jones-Foreman, Christine; Trinchieri, Ginevra; Golub, Leon; Bookbinder, Jay; Seward, Frederick D.; Zombeck, Martin V.
1994-01-01
Reports include: High Resolution Observations of the Central Region of M31; The X-ray Emission of Low-X-ray-Luminosity Early-Type Galaxies: Gas Versus Compact Sources; Interaction Between Cluster Gas and Radio Features of Cygnus A; Hot Gas and Dark Halos in Early-Type Galaxies; A Gravitational Lens in X-rays - 0957+461; How Massive are Early-Type Galaxies?; Three Crab-Like SNR in the Large Magellanic Cloud; and Soft X-ray Emission from Boundary Layers in Cataclysmic Variables. Papers submitted to the Astrophysical Journal are attached.
The White Dwarf Mass and the Accretion Rate of Recurrent Novae: An X-ray Perspective
NASA Technical Reports Server (NTRS)
Mukai, Koji; Sokoloski, Jennifer L.; Nelson, Thomas; Luna, Gerardo J. M.
2011-01-01
We present recent results of quiescent X-ray observations of recurrent novae (RNe) and related objects. Several RNe are luminous hard X-ray sources in quiescence, consistent with accretion onto a near Chandrasekhar mass white dwarf. Detection of similar hard X-ray emissions in old novae and other cataclysmic variables may lead to identification of additional RN candidates. On the other hand, other RNe are found to be comparatively hard X-ray faint. We present several scenarios that may explain this dichotomy, which should be explored further.
Identification of 4U 1849-31 with V1223 Sagittarii and discovery of optical pulsations
NASA Technical Reports Server (NTRS)
Steiner, J. E.; Schwartz, D. A.; Jablonski, F. J.; Busko, I. C.; Watson, M. G.; Pye, J. P.; Mchardy, I. M.
1981-01-01
The X-ray source 4U 1849-31 is identified with the 13 mag star V1223 Sgr, on the basis of a precise HEAO 1 modulation collimator X-ray position uniquely selected by the Ariel-5 sky survey location. It is shown by optical spectroscopy and photometry that V1223 Sgr is a cataclysmic variable, displaying a photometric period of 13.2 min that is interpreted as being due to the rotation of a degenerate dwarf. The similarity of this system to H2252-035 is noted.
A televised entertainment-education drama to promote positive discussion about organ donation
Khalil, Georges E.; Rintamaki, Lance S.
2014-01-01
This article investigates pathways between the exposure to an entertainment-education (E-E) television drama called Three Rivers and positive discussion of organ donation among viewers of the drama in the United States. A cross-sectional survey was conducted using an online advertising for a period of one week. Survey participants included 1325 adults living in the United States, who had viewed the first episode of Three Rivers on television. Data were collected on recall of events in the storyline, perceived entertainment value, perceived accuracy of the presented health information, rejection of organ donation myths and positive discussion of organ donation and the storyline. Covariates were registration for organ donation, membership to the donation or transplant community and demographic variables. Results show that viewers with high recall of the storyline were more likely to reject myths about organ donation and engage in pro-donation discussions with others. Perceived entertainment value and perceived accuracy acted as mediators in such relationships. The insertion of accurate health information in television drama may be effective in promoting positive discussions about organ donation and myth rejection. Recall of events from the televised E-E drama Three Rivers, entertainment value and accuracy perception were associated with positive discussion. PMID:24399264
Johnson, Lauren; Chen, Tzu-An; Hughes, Sheryl O; O'Connor, Teresia M
2015-05-28
Television (TV) viewing has been associated with many undesirable outcomes for children, such as increased risk of obesity, but TV viewing can also have benefits. Although restrictive parenting practices are effective in reducing children's TV viewing, not all parents use them and it is currently unclear why. The current study examined parenting practices related to TV viewing in the context of social- cognitive theory. Specifically, we hypothesized that positive and negative Parental Outcome Expectations for child's TV Viewing (POETV) would be associated with social co-viewing and restrictive parenting practices, and that POETV and parenting practices influence the amount of TV viewed by child. Data were collected from an internet survey of 287 multi-ethnic parents and their 6-12 year old children on participants' sociodemographic information, parenting practices related to TV use, POETV, and parent and child TV viewing. Path analysis was used to examine the relationship amongst variables in separate models for weekday and weekend TV viewing. controlling for child age, household education, and parental TV viewing. The results provided partial support for the hypotheses, with notable differences between weekday and weekend viewing. The models explained 13.6% and 23.4% of the variance in children's TV viewing on weekdays and weekends respectively. Neither positive nor negative POETV were associated with restrictive TV parenting in either model. One subscale each from positive and negative POETV were associated with social co-viewing parenting on both weekends and weekdays in the expected direction. Restrictive parenting practices were directly negatively associated with children's TV viewing on weekdays, but not weekends. Social co-viewing parenting was directly positively associated with children's TV viewing on weekends, but not weekdays. The strongest influence on children's TV viewing was having a TV in the child's bedroom. Negative POETV was weakly associated with having a TV in the child's room. These findings suggest that POETV and parenting may have a greater impact on weekend TV viewing, when children tend to watch more TV, than weekday. The models suggest that POETV, parenting and especially removing the TV from children's rooms may be promising targets for interventions.
Muennig, Peter; Rosen, Zohn; Johnson, Gretchen
2013-06-01
Television viewing is associated with an increased risk of mortality, which could be caused by a sedentary lifestyle, the content of television programming (e.g., cigarette product placement or stress-inducing content), or both. We examined the relationship between self-reported hours of television viewing and mortality risk over 30 years in a representative sample of the American adult population using the 2008 General Social Survey-National Death Index dataset. We also explored the intervening variable effect of various emotional states (e.g., happiness) and beliefs (e.g., trust in government) of the relationship between television viewing and mortality. We find that, for each additional hour of viewing, mortality risks increased 4%. Given the mean duration of television viewing in our sample, this amounted to about 1.2 years of life expectancy in the United States. This association was tempered by a number of potential psychosocial mediators, including self-reported measures of happiness, social capital, or confidence in institutions. Although none of these were clinically significant, the combined mediation power was statistically significant (P < .001). Television viewing among healthy adults is correlated with premature mortality in a nationally representative sample of U.S. adults, and this association may be partially mediated by programming content related to beliefs or affective states. However, this mediation effect is the result of many small changes in psychosocial states rather than large effects from a few factors. Copyright © 2013 Elsevier Inc. All rights reserved.
NASA Technical Reports Server (NTRS)
Lang, A. L., Jr.
1971-01-01
Data presented in the appendices covers: (1) summary description of baseline power system; (2) revised thermal profile analysis; (3) design analysis of television monitor; (4) bioresearch module ground station support evaluation; (5) variable spin control analysis; and (6) bioresearch modules and work flow.
The Acoustical Presentation of Technical Information.
ERIC Educational Resources Information Center
Barnett, George A.
1992-01-01
Advocates listening to technical information in much the same way as scientists and engineers look at graphics to understand the relationships among variables. Specifies a number of potential benefits of this approach. Demonstrates the presentation of acoustic information with data on the frequency of television viewing from 1950 to 1988. (SR)
ERIC Educational Resources Information Center
Bauman, Karl E.; And Others
1991-01-01
Evaluates 3 1985-87 mass media campaigns designed to prevent smoking by adolescents, using data gathered by telephone contact with over 2,000 households. The campaigns had but a modest or indeterminate result. Radio proved as effective as television. (DM)
Profiling the Adolescent Soap Opera Viewer.
ERIC Educational Resources Information Center
Alexander, Alison; And Others
Observing that plot and character changes in the daytime television serials has increased the teen and preteen share of soap opera audiences, a study compared demographic, personal experience, and attitudinal variables among adolescent soap opera fans, occasional viewers, and nonviewers. Data were collected from 230 students in the classrooms of…
The Effects of Violent Video Games on Aggression: A Meta-Analysis.
ERIC Educational Resources Information Center
Sherry, John L.
2001-01-01
Cumulates findings across existing empirical research on the effects of violent video games to estimate overall effect size and discern important trends and moderating variables. Suggests there is a smaller effect of violent video games on aggression than has been found with television violence on aggression. (SG)
Qin, Pengmin; Duncan, Niall W; Chen, David Yen-Ting; Chen, Chi-Jen; Huang, Li-Kai; Huang, Zirui; Lin, Chien-Yuan E; Wiebking, Christine; Yang, Che-Ming; Northoff, Georg; Lane, Timothy J
2018-05-21
Neural activity varies continually from moment to moment. Such temporal variability (TV) has been highlighted as a functionally specific brain property playing a fundamental role in cognition. We sought to investigate the mechanisms involved in TV changes between two basic behavioral states, namely having the eyes open (EO) or eyes closed (EC) in vivo in humans. To these ends we acquired BOLD fMRI, ASL, and [ 18 F]-fluoro-deoxyglucose PET in a group of healthy participants (n = 15), along with BOLD fMRI and [ 18 F]-flumazenil PET in a separate group (n = 19). Focusing on an EO- vs EC-sensitive region in the occipital cortex (identified in an independent sample), we show that TV is constrained in the EO condition compared to EC. This reduction is correlated with an increase in energy consumption and with regional GABA A receptor density. This suggests that the modulation of TV by behavioral state involves an increase in overall neural activity that is related to an increased effect from GABAergic inhibition in addition to any excitatory changes. These findings contribute to our understanding of the mechanisms underlying activity variability in the human brain and its control. Copyright © 2018 IBRO. Published by Elsevier Ltd. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Milovantseva, Natalia, E-mail: nmilovan@uci.edu; Saphores, Jean-Daniel, E-mail: saphores@uci.edu
Highlights: ► US households are storing 84.1 million broken or obsolete (junk) TVs. ► They represent 2.12 million metric tons of scrap. ► The value of these materials is approximately $21 per TV. ► Our count models characterize US households who store junk TVs. ► Our results are useful for designing more effective TV recycling programs. - Abstract: Within the growing stockpile of electronic waste (e-waste), TVs are especially of concern in the US because of their number (which is known imprecisely), their low recycling rate, and their material content: cathode ray tube televisions contain lead, and both rear projectionmore » and flat panel displays contain mercury, in addition to other potentially toxic materials. Based on a unique dataset from a 2010 survey, our count models show that pro-environmental behavior, age, education, household size, marital status, gender of the head of household, dwelling type, and geographic location are statistically significant variables for explaining the number of broken or obsolete (junk) TVs stored by US households. We also estimate that they are storing approximately 84.1 million junk TVs, which represents 40 pounds of scrap per household. Materials in each of these junk TVs are worth $21 on average at January 2012 materials prices, which sets an upper bound on collecting and recycling costs. This information should be helpful for developing more effective recycling strategies for TVs in the e-waste stream.« less
Variable Stars with the Kepler Space Telescope
NASA Astrophysics Data System (ADS)
Molnár, L.; Szabó, R.; Plachy, E.
2016-12-01
The Kepler space telescope has revolutionized our knowledge about exoplanets and stars and is continuing to do so in the K2 mission. The exquisite photometric precision, together with the long, uninterrupted observations opened up a new way to investigate the structure and evolution of stars. Asteroseismology, the study of stellar oscillations, allowed us to investigate solar-like stars, and to peer into the insides of red giants and massive stars. But many discoveries have been made about classical variable stars, too, ranging from pulsators like Cepheids and RR Lyraes to eclipsing binary stars and cataclysmic variables, and even supernovae. In this review, which is far from an exhaustive summary of all results obtained with Kepler, we collected some of the most interesting discoveries, and ponder on the role for amateur observers in this golden era of stellar astrophysics.
[Extracurricular activities of adolescents useful for smoking prevention programs. OCTOPUS team].
López González, M L; López, T; Comas Fuentes, A; Herrero Puente, P; González Blázquez, J; Cueto Espinar, A; Thomas, H; Douglas, J; Markham, W; Charlton, A; de Vries, H; Leijs, I; Mester, I; Ausems, M
1999-01-01
The cigarette smoking habit continues to be prevalent to a greater degree than would be desirable among teenagers. Innovative prevention programs are needed. This descriptive cross-sectional study sets out the behavior variables related to the cigarette smoking habit and the extracurricular activities in which teenagers are most frequently involved which are useful for setting out extracurricular prevention programs. The data was collected by means of a questionnaire validated in a representative sample of school age youths (ages 10-11 and 13-14) from Asturias. The variables entailed in cigarette smoking were analyzed using the regression method. The starting smoker percentage is 14.5%-42.5%, regular smokers totaling 1.1% and 12.4%, respectively. Two models were constructed with the variables significantly related to smoking behavior, which are properly classified into smoker/non-smoker by 98.85% and 91.39% of the children, by ages. The environmental variables (availability of cigarettes and alcoholic beverages and regular visits to places entailing risk) are the major aspects comprising the model. The most common extracurricular activities are: watching TV, reading and listening to music and watching or playing sports. The findings provide keys to planning extracurricular activities tailored to fit in with the activities most popular among teens: TV commercials and ads on music media (CD's, tapes, etc.) and printed information mailed directly to teens at their homes, with messages conveyed by opinion-leaders among teens in the fields of sports, music and television.
NASA Astrophysics Data System (ADS)
Michael, Greg; Basilevsky, Alexander; Neukum, Gerhard
2018-03-01
This work revisits the hypothesis of the so-called 'lunar terminal cataclysm' suggested by Tera et al. (1973, 1974) as a strong peak in the meteorite bombardment of the Moon around 3.9 Ga ago. According to the hypothesis, most of the impact craters observed on the lunar highlands formed during this short time period and thus formed the majority of the lunar highland impact breccias and melts. The hypothesis arose from the observation that the ages of highland samples from all the lunar missions are mostly grouped around 3.9-4.0 Ga. Since those missions, however, radiometric dating techniques have progressed and many samples, both old and new, have been re-analyzed. Nevertheless, the debate over whether there was a terminal cataclysm persists. To progress in this problem we summarized results of 269 K-Ar datings (mostly made using the 40Ar-39Ar technique) of highland rocks represented by the Apollo 14, 15, 16, 17 and Luna 20 samples and 94 datings of clasts of the highland rocks from 23 lunar meteorites representing 21 localities on the lunar surface, and considered them jointly with the results of our modelling of the cumulative effect of the impact gardening process on the presence of impact melt of different ages at the near-surface of the Moon. The considered results of K-Ar dating of the Apollo-Luna samples of lunar highland rocks confirmed a presence of strong peak centered at 3.87 Ga. But since the time when the hypothesis of terminal cataclysm was suggested, it has become clear that this peak could be a result of sampling bias: it is the only prominent feature at the sites with an apparent domination of Imbrium basin ejecta (Apollo 14 and 15) and the age pattern is more complicated for the sites influenced not only by Imbrium ejecta but also that of other basins (Nectaris at the Apollo 16 site and Serenitatis at the Apollo 17 site). Our modelling shows that the cataclysm, if it occurred, should produce a strong peak in the measured age values but we see in the considered histograms and relative probability plots not only the 3.87 Ga peak (due to Imbrium basin), but also several secondary peaks caused by the formation of other basins distributed between 3.87 and 4.25 Ga. The lunar terminal cataclysm hypothesis is in disagreement with the distribution of K-Ar ages for the highland rocks of the lunar meteorites. The population of lunar meteorites representing localities randomly distributed over the lunar surface, and thus free from the mentioned sampling bias, shows no ∼3.9 Ga peak as it should, if the cataclysm did occur. We conclude that the statistics of sample ages contradict the terminal cataclysm scenario in the bombardment of the Moon. We also see evidence for the formation of several impact basins between 3.87 and 4.25 Ga which is likewise incompatible with the hypothesis of a short interval cataclysm. There remain other basins, including the largest South Pole - Aitken, the ages of which should be determined in future studies to further clarify the impact history. Sample-return missions targeted to date several key basins need to be planned, and the continued study of lunar meteorites may also bring new details to the general view of the impact bombardment of the Moon.
NASA Technical Reports Server (NTRS)
Catelli, Jennifer
1992-01-01
The x-ray emissions of AM Herculis-type object H0538+608 were observed using the ROSAT satellite. Evidence was found for a highly varying soft x-ray component with a much lower intensity than is typical for this class. The spectrum was well fit by a thermal bremsstrahlung model (exponential plus gaunt factor) of 35 +/- 5 KeV plus a 0.05 +/- 0.01 KeV blackbody component, with absorption by interstellar medium with a neutral hydrogen column density of log N(sub H) (atoms/sq cm) = 20.2. No obvious periodic variations were found. There was very little correlation between the hard and soft x-ray bands.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kaluzny, J.; Rozanska, A.; Rozyczka, M.
2012-05-01
We show that the optical counterpart of the X-ray source CX 1 in M4 is a {approx}20th magnitude star, located in the color-magnitude diagram on (or very close to) the main sequence of the cluster, and exhibiting sinusoidal variations of the flux. We find the X-ray flux to be also periodically variable, with X-ray and optical minima coinciding. Stability of the optical light curve, lack of UV-excess, and unrealistic mean density resulting from period-density relation for semidetached systems speak against the original identification of CX 1 as a cataclysmic variable. We argue that the X-ray active component of this systemmore » is a neutron star (probably a millisecond pulsar).« less
Cultural variations in children's coping behaviour, TV viewing time, and family functioning.
Chen, J-L; Kennedy, C
2005-09-01
To examine children's coping behaviour, TV viewing hours and family functioning in four ethnic groups and factors related to children's coping behaviour. This study was part of two larger research projects investigating children's health behaviours in the United States and Taiwan. Fifty-six White American children of European ancestry, 66 Mexican American children, 68 Chinese American children and 95 native Taiwanese children were included in the analysis. Standardized instruments were used to measure coping strategies, children's TV viewing hours and family functioning. There were significant differences in the types of stressor that children of different ethnicity reported. Similarities and differences were found in the four ethnic groups regarding the top five most frequently used and most effective coping strategies. Multiple regressions identified two variables that contributed significantly to the variance in the frequency of children's coping strategies--ethnicity and poorer behaviour control in the family. Ethnicity was the only variable found to contribute to the variance in coping effectiveness. Significant differences were found in the number of hours children spent watching TV. Findings suggest that children of different ethnicity utilized different types of coping strategies and ethnicity is one of the important factors related to children's coping behaviour. These findings provide evidence for nurses to assess children's coping behaviour and TV viewing and provide children with healthier alternatives.
NASA Astrophysics Data System (ADS)
Andronov, I. L.
The biography of Vladimir Platonovich Tsesevich (11.11.1907 - 28.10.1983), a leader of the astronomy in Odessa from 1944 to 1983, is briefly reviewed, as well as the directions of study, mainly the highlights of the research of variable stars carried out by the members of the scientific school founded by him. The directions of these studies cover a very wide range of variability types - "magnetic" and "non-magnetic" cataclysmic variables, symbiotic, X-Ray and other interacting binaries, classical eclipsers and "extreme direct impactors", pulsating variables from DSct and RR through C and RV to SR and M. Improved algorithms and programs have been elaborated for statistically optimal phenomenological and physical modeling. Initially these studies in Odessa were inspired by ("with a capital letter") Vladimir Platonovich Tsesevich. who was a meticulous Scientist and brilliant Educator, thorough Author and the intelligibly explaining Popularizer, persevering Organizer and cheerful Joker - a true Professor and Teacher. He was the "Poet of the Starry Heavens".
New cataclysmic variables and other exotic binaries in the globular cluster 47 Tucanae*
NASA Astrophysics Data System (ADS)
Rivera Sandoval, L. E.; van den Berg, M.; Heinke, C. O.; Cohn, H. N.; Lugger, P. M.; Anderson, J.; Cool, A. M.; Edmonds, P. D.; Wijnands, R.; Ivanova, N.; Grindlay, J. E.
2018-04-01
We present 22 new (+3 confirmed) cataclysmic variables (CVs) in the non-core-collapsed globular cluster 47 Tucanae (47 Tuc). The total number of CVs in the cluster is now 43, the largest sample in any globular cluster so far. For the identifications we used near-ultraviolet (NUV) and optical images from the Hubble Space Telescope, in combination with X-ray results from the Chandra X-ray Observatory. This allowed us to build the deepest NUV CV luminosity function of the cluster to date. We found that the CVs in 47 Tuc are more concentrated towards the cluster centre than the main-sequence turn-off stars. We compared our results to the CV populations of the core-collapsed globular clusters NGC 6397 and NGC 6752. We found that 47 Tuc has fewer bright CVs per unit mass than those two other clusters. That suggests that dynamical interactions in core-collapsed clusters play a major role creating new CVs. In 47 Tuc, the CV population is probably dominated by primordial and old dynamically formed systems. We estimated that the CVs in 47 Tuc have total masses of ˜1.4 M⊙. We also found that the X-ray luminosity function of the CVs in the three clusters is bimodal. Additionally, we discuss a possible double degenerate system and an intriguing/unclassified object. Finally, we present four systems that could be millisecond pulsar companions given their X-ray and NUV/optical colours. For one of them we present very strong evidence for being an ablated companion. The other three could be CO or He white dwarfs.
EC 10246-2707: an eclipsing subdwarf B + M dwarf binary
NASA Astrophysics Data System (ADS)
Barlow, B. N.; Kilkenny, D.; Drechsel, H.; Dunlap, B. H.; O'Donoghue, D.; Geier, S.; O'Steen, R. G.; Clemens, J. C.; LaCluyze, A. P.; Reichart, D. E.; Haislip, J. B.; Nysewander, M. C.; Ivarsen, K. M.
2013-03-01
We announce the discovery of a new eclipsing hot subdwarf B + M dwarf binary, EC 10246-2707, and present multicolour photometric and spectroscopic observations of this system. Similar to other HW Vir-type binaries, the light curve shows both primary and secondary eclipses, along with a strong reflection effect from the M dwarf; no intrinsic light contribution is detected from the cool companion. The orbital period is 0.118 507 9936 ± 0.000 000 0009 d, or about 3 h. Analysis of our time series spectroscopy reveals a velocity semi-amplitude of K1 = 71.6 ± 1.7 km s-1 for the sdB and best-fitting atmospheric parameters of Teff = 28 900 ± 500 K, log g = 5.64 ± 0.06 and log N(He)/N(H) = -2.5 ± 0.2. Although we cannot claim a unique solution from modelling the light curve, the best-fitting model has an sdB mass of 0.45 M⊙ and a cool companion mass of 0.12 M⊙. These results are roughly consistent with a canonical-mass sdB and M dwarf separated by a ˜ 0.84 R⊙. We find no evidence of pulsations in the light curve and limit the amplitude of rapid photometric oscillations to <0.08 per cent. Using 15 yr of eclipse timings, we construct an observed minus calculated (O - C) diagram but find no statistically significant period changes; we rule out |dot{P}| > 7.2 × 10^{-12}. If EC 10246-2707 evolves into a cataclysmic variable, its period should fall below the famous cataclysmic variable period gap.
Radiative Reverse Shock Laser Experiments Relevant to Accretion Processes in Cataclysmic Variables
NASA Astrophysics Data System (ADS)
Krauland, Christine
2012-10-01
We present results from experiments that explore radiative reverse shock waves and their contribution to the evolving dynamics of the cataclysmic variable (CV) system in which they reside. CVs are close binary star systems containing a white dwarf (WD) that accretes matter from its late-type main sequence companion star. In the process of accretion, a reverse shock forms when the supersonic infalling plasma is impeded. It provides the main source of radiation in the binary systems. In the case of a non-magnetic CV, the impact on an accretion disk produces this ``hot spot,'' where the flow obliquely strikes the rotating accretion disk. This collision region has many ambiguities as a radiation hydrodynamic system, but shock development in the infalling flow can be modeled [1]. We discuss the production of radiative reverse shocks in experiments at the Omega-60 laser facility. The ability of this high-intensity laser to create large energy densities in targets having millimeter-scale volumes makes it feasible to create supersonic plasma flows. Obtaining a radiative reverse shock in the laboratory requires a sufficiently fast flow (> 60 km/s) within a material whose opacity is large enough to produce energetically significant emission from experimentally achievable layers. We will show the radiographic and emission data from three campaigns on Omega-60 with accompanying CRASH [2] simulations, and will discuss the implications in the context of the CV system. [4pt] [1] Armitage, P. J. and Livio, M., ApJ, 493, 898 (1998).[0pt] [2] van der Holst, B., Toth, G., Sokolov, I.V., et al., ApJS, 194, 23 (2011).
New pulsating white dwarfs in cataclysmic variables
NASA Astrophysics Data System (ADS)
Nilsson, R.; Uthas, H.; Ytre-Eide, M.; Solheim, J.-E.; Warner, B.
2006-07-01
The number of discovered non-radially pulsating white dwarfs (WDs) in cataclysmic variables (CVs) is increasing rapidly by the aid of the Sloan Digital Sky Survey (SDSS). We performed photometric observations of two additional objects, SDSS J133941.11+484727.5 (SDSS 1339), independently discovered as a pulsator by Gänsicke et al., and SDSS J151413.72+454911.9, which we identified as a CV/ZZ Ceti hybrid. In this Letter we present the results of the remote observations of these targets performed with the Nordic Optical Telescope (NOT) during the Nordic-Baltic Research School at Molėtai Observatory, and follow-up observations executed by NOT in service mode. We also present three candidates we found to be non-pulsating. The results of our observations show that the main pulsation frequencies agree with those found in previous CV/ZZ Ceti hybrids, but specifically for SDSS 1339 the principal period differs slightly between individual observations and also from the recent independent observation by Gänsicke et al. Analysis of SDSS colour data for the small sample of pulsating and non-pulsating CV/ZZ Ceti hybrids found so far seems to indicate that the r - i colour could be a good marker for the instability strip of this class of pulsating WDs. Based on observations made with the Nordic Optical Telescope, operated on the island of La Palma jointly by Denmark, Finland, Iceland, Norway, and Sweden, in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofisica de Canarias. E-mail: ricky@astro.lu.se
Parental Decision Making about Technology and Quality in Child Care Programs
ERIC Educational Resources Information Center
Rose, Katherine K.; Vittrup, Brigitte; Leveridge, Tinney
2013-01-01
Background: This study investigated parental decision making about non-parental child care programs based on the technological and quality components of the program, both child-focused and parent-focused. Child-focused variables related to children's access to technology such as computers, educational television programming, and the internet.…
Beyond Exposure: A Person-Oriented Approach to Adolescent Media Diets
ERIC Educational Resources Information Center
Schooler, Deborah; Sorsoli, C. Lynn; Kim, Janna L.; Tolman, Deborah L.
2009-01-01
Research on adolescents' use of sexual media has been dominated by a variable-oriented perspective, focusing on incremental effects of media exposure on sexual behavior. The present investigation examines the ways in which adolescents select and organize their television viewing. This study used cluster analysis to identify, validate, and describe…
Association between television, movie, and video game exposure and school performance.
Sharif, Iman; Sargent, James D
2006-10-01
The relationship between media exposure and school performance has not been studied extensively in adolescents. The purpose of this work was to test the relative effects of television, movie, and video game screen time and content on adolescent school performance. We conducted a population-based cross-sectional survey of middle school students (grades 5-8) in the Northeastern United States. We looked at weekday television and video game screen time, weekend television and video game screen time, cable movie channel availability, parental R-rated movie restriction, and television content restriction. The main outcome was self-report of school performance (excellent, good, average, or below average). We used ordinal logistic-regression analysis to test the independent effects of each variable, adjusting for demographics, child personality, and parenting style. There were 4508 students who participated in the study; gender was equally represented, and 95% were white. In multivariate analyses, after adjusting for other covariates, the odds of poorer school performance increased with increasing weekday television screen time and cable movie channel availability and decreased with parental restriction of television content restriction. As compared with children whose parents never allowed them to watch R-rated movies, children who watched R-rated movies once in a while, sometimes, or all of the time had significantly increased cumulative odds of poorer school performance. Weekend screen time and video game use were not associated with school performance. We found that both content exposure and screen time had independent detrimental associations with school performance. These findings support parental enforcement of American Academy of Pediatrics guidelines for media time (particularly weekdays) and content limits to enhance school success.
Martínez-Alarcón, L; Ríos, A; Ramis, G; López-Navas, A; Febrero, B; Ramírez, P; Parrilla, P
2013-01-01
Journalists and the information they disseminate are essential to promote health and organ donation and transplantation (ODT). The attitude of journalism students toward ODT could influence public opinion and help promote this treatment option. The aim of this study was to determine the media through which journalism students receive information on ODT and to analyze the association between the sources of information and psychosocial variables. We surveyed journalism students (n = 129) recruited in compulsory classes. A validated psychosocial questionnaire (self-administered, anonymous) about ODT was used. Student t test and χ(2) test were applied. Questionnaire completion rate was 98% (n = 126). The medium with the greatest incidence on students was television (TV), followed by press and magazines/books. In the factor analysis to determine the impact of the information by its source, the first factor was talks with friends and family; the second was shared by hoardings/publicity posters, health professionals, and college/school; and the third was TV and radio. In the factor analysis between information sources and psychosocial variables, the associations were between information about organ donation transmitted by friends and family and having spoken about ODT with them; by TV, radio, and hoardings and not having spoken in the family; and by TV/radio and the father's and mother's opinion about ODT. The medium with the greatest incidence on students is TV, and the medium with the greatest impact on broadcasting information was conversations with friends, family, and health professionals. This could be useful for society, because they should be provided with clear and concise information. Copyright © 2013 Elsevier Inc. All rights reserved.
Media use, cancer knowledge and lifestyle choices: a cross-sectional analysis.
Nelissen, Sara; Beullens, Kathleen; Lemal, Marijke; Van den Bulck, Jan
2015-10-01
Both media use and cancer knowledge have been identified as important predictors of a healthy lifestyle. However, little is known about the interplay between these two variables, and about differences between cancer diagnosed and non-diagnosed consumers of media and knowledge. This study investigated the relationship between media use (television and internet exposure) and lifestyle choices of cancer diagnosed and non-diagnosed individuals, and looked at the influence of cancer knowledge on this relationship. A cross-sectional, quantitative survey (the Leuven Cancer Information Survey) was administered to 621 cancer diagnosed and 1387 non-diagnosed individuals, aged 16-88 years old in Flanders (Belgium). Bivariate analyses, hierarchical linear regression analyses and advanced moderation and mediation analyses were conducted. Internet exposure was not a predictor of lifestyle choices. Television exposure, however, was a negative predictor of healthy lifestyle choices. Moreover, television exposure was a direct negative predictor of cancer knowledge, which in turn positively predicted lifestyle choices. However, no differences were found in the investigated relationships between the two subsamples. These results indicate that higher levels of television exposure coincide with less cancer knowledge and with less healthy lifestyle choices. It offers a pathway for intervention by suggesting that improving cancer knowledge through television might positively affect lifestyle choices. © The Author 2015. Published by Oxford University Press on behalf of the European Public Health Association. All rights reserved.
Hirpara, Darshna G; Gajera, H P; Hirapara, Jaydeep G; Golakiya, B A
2017-11-01
Trichoderma is one of the most exploited biocontrol agent for the management of plant diseases. Twenty strains of Trichoderma (six of T. harzianum, four of T. viride, three of T. virens, three of T. koningii, each one of T. hamatum, T. reesei, T. parceramosum and Trichoderma spp.) subjected to in vitro antagonism up to 12days after inoculation against Sclerotium rolfsii Sacc. causing stem rot in groundnut. A new concept was developed to determine inhibition coefficient representing pathogen biology and biocontrol related biophysical variables. Results explained differential inhibition coefficient of test pathogen by Trichoderma antagonists. The inhibition coefficient of test pathogen was examined highest (91.13%) by T. virens NBAII Tvs12 followed by T. virens MTCC 794 (89.33%) and T. koningii MTCC 796 (62.39%). Microscopic study confirmed biocontrol mechanism as mycoparasitism for Tvs12 and antibiosis for T. koningii MTCC 796. The sclerotial biogenesis of test pathogen was elevated during weak antagonism and diminished in interactions with strong antagonists. The inhibition coefficient of S. rolfsii was significantly negatively correlated with sclerotia formation and lipid peroxidation during the antagonism. Trichoderma strains were screened for fungicides (carbendazim and tebuconazole, thiram and mancozeb) and abiotic stress (drought and salt) tolerance. Results indicated that T. koningii MTCC 796 efficiently grew better than the other strains with maximum radial growth under adverse conditions. The genetic variability among the Trichoderma was determined using 34 gene specific markers which amplified 146 alleles. The SSR similarities explained substantial diversity (15 to 87%) across Trichoderma strains and pathogen S. rolfsii. Principal coordinates analysis (PCA) were comparable to the cluster analysis and first three most informative PC components explained 64.45% of the total variation. In PCA, potent antagonists appear to be distinct from other strains. Five SSR markers T1F/T1R (311) , TvCTT56f/TvCTT56r (387) , TvGAT18f/TvGAT18r (364) , TvCA39f/TvCA39r (196) and TvAG29f/TvAG29r (418) found to be unique to distinguish best antagonist strain Tvs12. However, MTCC 796 was examined most stress tolerant strain with better inhibition coefficient which might be useful to control the disease under adverse conditions or as a part of integrated pest management. Copyright © 2017. Published by Elsevier B.V.
The Immediate and Delayed Effects of TV: Impacts of Gender and Processed-Food Intake History.
Francis, Heather M; Stevenson, Richard J; Oaten, Megan J; Mahmut, Mehmet K; Yeomans, Martin R
2017-01-01
Eating while watching TV has generally been found to increase both immediate and delayed energy intake. Here we examine two factors - gender and habitual processed-food intake - that may moderate these effects. Participants [ n = 153; 95 women, 58 men; M age = 19.7 ( SD = 2.9); M BMI = 22.4 ( SD = 3.1)] ate an ad libitum snack either with or without TV, followed around 1 h later by lunch. There was an interaction between TV and gender for both meals. Women tended to consume more snack food in the TV condition, with men consuming more in the no-TV condition. Participants who habitually consumed more processed food also ate more snacks, independent of any other variable, including rated liking. At lunch, men who had earlier snacked with TV ate more than men who had snacked without TV, but this effect was not evident in women. On memory recall, all participants underestimated how much snack food they had eaten, and this was a function of how much they had actually consumed, with greater error only predicted by greater consumption. The results indicate that the effects of TV on eating can vary with gender and that processed-food history can predict snack food intake. While previous findings suggest memory of prior-intake may be impaired by eating while watching TV, the current results suggest this is not necessarily because of TV per se , but because people sometimes consume more food under such conditions.
The Immediate and Delayed Effects of TV: Impacts of Gender and Processed-Food Intake History
Francis, Heather M.; Stevenson, Richard J.; Oaten, Megan J.; Mahmut, Mehmet K.; Yeomans, Martin R.
2017-01-01
Eating while watching TV has generally been found to increase both immediate and delayed energy intake. Here we examine two factors – gender and habitual processed-food intake – that may moderate these effects. Participants [n = 153; 95 women, 58 men; Mage = 19.7 (SD = 2.9); MBMI = 22.4 (SD = 3.1)] ate an ad libitum snack either with or without TV, followed around 1 h later by lunch. There was an interaction between TV and gender for both meals. Women tended to consume more snack food in the TV condition, with men consuming more in the no-TV condition. Participants who habitually consumed more processed food also ate more snacks, independent of any other variable, including rated liking. At lunch, men who had earlier snacked with TV ate more than men who had snacked without TV, but this effect was not evident in women. On memory recall, all participants underestimated how much snack food they had eaten, and this was a function of how much they had actually consumed, with greater error only predicted by greater consumption. The results indicate that the effects of TV on eating can vary with gender and that processed-food history can predict snack food intake. While previous findings suggest memory of prior-intake may be impaired by eating while watching TV, the current results suggest this is not necessarily because of TV per se, but because people sometimes consume more food under such conditions. PMID:28979225
Wakefield, Melanie; Bayly, Megan; Durkin, Sarah; Cotter, Trish; Mullin, Sandra; Warne, Charles
2013-01-01
While television advertisements (ads) that communicate the serious harms of smoking are effective in prompting quitting-related thoughts and actions, little research has been conducted among smokers in low- to middle-income countries to guide public education efforts. 2399 smokers aged 18-34 years in 10 low- to middle-income countries (Bangladesh, China, Egypt, India, Indonesia, Mexico, Philippines, Russia, Turkey and Vietnam) viewed and individually rated the same five anti-smoking ads on a standard questionnaire and then engaged in a structured group discussion about each ad. Multivariate logistic regression analysis, with robust SEs to account for the same individual rating multiple ads, was performed to compare outcomes (message acceptance, perceived personalised effectiveness, feel uncomfortable, likelihood of discussing the ad) across ads and countries, adjusting for covariates. Ads by country interactions were examined to assess consistency of ratings across countries. Three ads with graphic imagery performed consistently highly across all countries. Two of these ads showed diseased human tissue or body parts, and a third used a disgust-provoking metaphor to demonstrate tar accumulation in smokers' lungs. A personal testimonial ad performed more variably, as many smokers did not appreciate that the featured woman's lung cancer was due to smoking or that her altered physical appearance was due to chemotherapy. An ad using a visual metaphor for lung disease was also more variable, mostly due to lack of understanding of the term 'emphysema'. Television ads that graphically communicate the serious harms of tobacco use are likely to be effective with smokers in low- to middle-income countries and can be readily translated and adapted for local use. Ads with complex medical terms or metaphors, or those that feature personal testimonials, are more variable and at least require more careful pre-testing and adaptation to maximise their potential.
Neighborhood disorder and screen time among 10-16 year old Canadian youth: A cross-sectional study
2012-01-01
Background Screen time activities (e.g., television, computers, video games) have been linked to several negative health outcomes among young people. In order to develop evidence-based interventions to reduce screen time, the factors that influence the behavior need to be better understood. High neighborhood disorder, which may encourage young people to stay indoors where screen time activities are readily available, is one potential factor to consider. Methods Results are based on 15,917 youth in grades 6-10 (aged 10-16 years old) who participated in the Canadian 2009/10 Health Behaviour in School-aged Children Survey (HBSC). Total hours per week of television, video games, and computer use were reported by the participating students in the HBSC student questionnaire. Ten items of neighborhood disorder including safety, neighbors taking advantage, drugs/drinking in public, ethnic tensions, gangs, crime, conditions of buildings/grounds, abandoned buildings, litter, and graffiti were measured using the HBSC student questionnaire, the HBSC administrator questionnaire, and Geographic Information Systems. Based upon these 10 items, social and physical neighborhood disorder variables were derived using principal component analysis. Multivariate multilevel logistic regression analyses were used to examine the relationship between social and physical neighborhood disorder and individual screen time variables. Results High (top quartile) social neighborhood disorder was associated with approximately 35-45% increased risk of high (top quartile) television, computer, and video game use. Physical neighborhood disorder was not associated with screen time activities after adjusting for social neighborhood disorder. However, high social and physical neighborhood disorder combined was associated with approximately 40-60% increased likelihood of high television, computer, and video game use. Conclusion High neighborhood disorder is one environmental factor that may be important to consider for future public health interventions and strategies aiming to reduce screen time among youth. PMID:22651908
R-rated movies, bedroom televisions, and initiation of smoking by white and black adolescents.
Jackson, Christine; Brown, Jane D; L'Engle, Kelly L
2007-03-01
To test movie exposure and television use as predictors of smoking initiation among white and black adolescents who had never smoked cigarettes. Survey research using audio computer-assisted self-interviews at baseline and at 2-year follow-up (2002-2004). Participants' homes located in central North Carolina. A sample of 735 12- to 14-year-old adolescents drawn from 14 public middle schools. Frequency of exposure to movies rated R, PG-13, PG, or G; frequency, location, and parental oversight of television viewing. Initiation of smoking, indicated by the first occasion of puffing on a cigarette. Among white adolescents, high relative exposure to R-rated movies predicted a significantly greater likelihood of smoking initiation at follow-up, and private access to television during early adolescence, indicated by having a bedroom television, was also a significant independent predictor of smoking initiation at follow-up. No significant associations were observed between any movie-exposure or television-use variables and likelihood of smoking among black adolescents. Indicators of risky media use were associated with a significantly greater likelihood of smoking for white but not for black adolescents. These results diverge strongly from past results, which have indicated that all adolescents, regardless of race or place of residence, have a higher risk of smoking initiation as their exposure to movie smoking increases. Research is needed to identify the antecedents of risky media use and to understand how audience attributes, including race and other factors, moderate the effects of risky media use on health-related behaviors.
Parent and child screen-viewing time and home media environment.
Jago, Russell; Stamatakis, Emmanuel; Gama, Augusta; Carvalhal, Isabel Mourão; Nogueira, Helena; Rosado, Vítor; Padez, Cristina
2012-08-01
Screen-viewing time has been associated with adverse health outcomes. Data on the predictors of youth screen-viewing time is predominately from older children in North America. Parental and home media environment factors that are associated with screen-viewing time could be targeted in interventions. Examine if parental screen-viewing time and electronic media (access to game equipment, TVs, PCs, and laptops) environment factors were associated with Portuguese children's screen-viewing time and if associations differed by child age (<7 vs ≥7 years); gender; or type of screen viewing. Data are reported for 2965 families with children aged 3-10 years. Data were collected in 2009-2010 and analyzed in 2011. Outcomes were child spending ≥2 hours watching TV and ≥1 hour per day playing with combined other media. Exposures were mothers and fathers watching ≥2 hours of TV and electronic media variables. Parental TV-viewing time was strongly associated with child weekday and weekend TV-viewing time across all four gender and age subgroups. Maternal TV-viewing time was a stronger predictor of child TV-viewing time than paternal TV-viewing time. There was very limited evidence that parental TV-viewing time was associated with combined other media time among boys or girls. Access to electronic game equipment increased the likelihood that children spent >1 hour using combined other media on weekdays and weekend days. Parental TV-viewing time was associated with Portuguese children's TV-viewing time. The numbers of TVs in the household and electronic games equipment access were also associated with TV- and combined other media-viewing/usage time. Copyright © 2012 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.
The eclipsing AM Herculis variable H1907 + 690
NASA Technical Reports Server (NTRS)
Remillard, R. A.; Silber, A.; Stroozas, B. A.; Tapia, S.
1991-01-01
The discovery is reported of an eclipsing cataclysmic variable that exhibits up to 10 percent circular polarization at optical wavelengths, securing its classification as an AM Herculis type binary. The object, H1907 + 609, was located with the guidance of X-ray positions from the HEAO 1 survey. Optical CCD photometry exhibits deep eclipses, from which is derived a precise orbital period of 1.743750 hr. The eclipse duration suggests an inclination angle about 80 deg for a main-sequence secondary star. The optical flux has been persistently faint during observations spanning 1987-1990, while the X-ray measurements suggest long-term X-ray variability. The polarization and photometric light curves can be interpreted with a geometric model in which most of the accretion is directed toward a single magnetic pole, with an accretion spot displaced about 17 deg in longitude from the projection of the secondary star on the white dwarf surface.
Discovery of a Wolf-Rayet Star through Detection of Its Photometric Variability
NASA Astrophysics Data System (ADS)
Littlefield, Colin; Garnavich, Peter; Marion, G. H. Howie; Vinkó, József; McClelland, Colin; Rettig, Terrence; Wheeler, J. Craig
2012-06-01
We report the serendipitous discovery of a heavily reddened Wolf-Rayet star that we name WR 142b. While photometrically monitoring a cataclysmic variable, we detected weak variability in a nearby field star. Low-resolution spectroscopy revealed a strong emission line at 7100 Å, suggesting an unusual object and prompting further study. A spectrum taken with the Hobby-Eberly Telescope confirms strong He II emission and an N IV 7112 Å line consistent with a nitrogen-rich Wolf-Rayet star of spectral class WN6. Analysis of the He II line strengths reveals no detectable hydrogen in WR 142b. A blue-sensitive spectrum obtained with the Large Binocular Telescope shows no evidence for a hot companion star. The continuum shape and emission line ratios imply a reddening of E(B - V) = 2.2-2.6 mag. We estimate that the distance to WR 142b is 1.4 ± 0.3 kpc.
ERIC Educational Resources Information Center
Clark, Levina; Tiggemann, Marika
2008-01-01
This study investigated the prospective predictors of body image in 9- to 12-year-old girls. Participants were 150 girls in Grades 4-6 with a mean age of 10.3 years. Girls completed questionnaire measures of media and peer influences (television/magazine exposure, peer appearance conversations), individual psychological variables (appearance…
The Effect of Program Context on Childrens' Learning from a Television News Story.
ERIC Educational Resources Information Center
Drew, Dan; Reeves, Byron
To test the assumptions that children's perceptions of a news program affect their learning and that their perceptions are in turn affected by age and program context, a study was undertaken involving 435 third through seventh graders. The specific independent and perceptual variables examined were: believability, liking the story and program,…
ERIC Educational Resources Information Center
White, Sylvia E.; And Others
In recent years, broadcast advertisers have become concerned with the tendency of video cassette recorder (VCR) owners to "zap"--fast forward delete--commercials. However, research has shown that viewers retain some recall of commercials, even with fast forward zapping, and it is to the benefit of advertisers to discover ways of…
ERIC Educational Resources Information Center
Lubbers, Charles A.
2002-01-01
Examines the value of two alternative tools as supplements for the traditional introduction to public relations course. Considers the usage of a study manual, usage of televised review sessions, year in school and major status. Indicates that all four variables are significantly correlated with class performance, but that the study manual explains…
ERIC Educational Resources Information Center
Bantz, Charles R.
1982-01-01
Results indicate respondents do not identify medium-specific or program-specific uses. Lack of differentiation suggests: (1) additional assessment of the relationship of medium and content is needed and (2) medium and content should be considered related variables in uses and gratification research, and research not incorporating their interaction…
OV Bootis: Forty Nights Of World-Wide Photometry
NASA Astrophysics Data System (ADS)
Patterson, Joseph; de Miguel, Enrique; Barret, Douglas; Brincat, Stephen; Boardman, James, Jr.; Buczynski, Denis; Campbell, Tut; Cejudo, David; Cook, Lew; Cook, Michael J.; Collins, Donald; Cooney, Walt; Dubois, Franky; Dvorak, Shawn; Halpern, Jules P.; Kroes, Anthony J.; Lemay, Damien; Licchelli, Domenico; Mankel, Dylan; Marshall, Matt; Novak, Rudolf; Oksanen, Arto; Roberts, George; Seargeant, Jim; Sears, Huei; Silcox, Austin; Slauson, Douglas; Stone, Geoff; Thorstensen, J. R.; Ulowetz, Joe; Vanmunster, Tonny; Wallgren, John; Wood, Matt
2017-06-01
Among the 1000 known cataclysmic variables, only one appears to belong to the "Galactic halo" - the Population II stars. We report round-the-world photometry of this star (OV Boo) during March-April 2017, when it staged its first certified dwarf-nova outburst. The star is remarkable for its short binary period (66 minutes), high proper motion, metal-poor composition, substellar secondary, sharp white-dwarf eclipses, and nonradial pulsations. Something for everybody...... and it even had the good manners to erupt in northern springtime, when it transits near local midnight. Move over, SS Cyg and WZ Sge; there's a new celebrity in town!
Far Ultraviolet Spectroscopic Explorer Spectroscopy of the Nova-Like Cataclysmic Variable BB Doradus
2008-06-27
which we have best-fit models in the parameter space, we use the infrared magnitudes J, H, and K from the Two Micron All Sky Survey ( 2MASS ) to assess the...in a high state with a visual red magnitude R ¼ 14:60 and a blue magnitude B ¼ 13:90 (whereas B 16:5 in the low state). The 2MASS IR apparent...therefore certainly larger than 300 pc, and most likely in the range of 500 pc. Since BB Dor was observed in a high state (with 2MASS ), it is likely
Optical identification of IGR J18308-1232 as a Cataclysmic Variable
NASA Astrophysics Data System (ADS)
Parisi, P.; Masetti, N.; Jimenez, E.; Chavushyan, V.; Bassani, L.; Bazzano, A.; Bird, A. J.
2008-09-01
We report on a spectroscopic analysis of optical sources inside the error circle of the XMM-Newton slew source XMMLS1 J183049.6-123218 (see Ibarra et al., ATel #1527), associated with the unidentified INTEGRAL source IGR J18308-1232 (Bird et al. 2007, ApJS, 170, 175). The observations were performed on 2008 June 28, starting at 06:37 UT, with the Boller & Chivens spectrograph mounted on the 2.1m telescope of the Observatorio Astronomico Nacional (San Pedro Martir, Baja California, Mexico), for a total exposure time of 7200 s.
Oscillations of Accretion Disks in Cataclysmic Variable Stars
NASA Astrophysics Data System (ADS)
Osaki, Y.
2013-12-01
The disk instability model for the outbursts of dwarf novae is reviewed, with particular attention given to the superoutburst of SU UMa stars. Two intrinsic instabilities in accretion disks of dwarf novae are known; the thermal instability and the tidal instability. The thermal-tidal instability model (abbreviated the TTI model), which combines these two instabilities, was first proposed in 1989 by Osaki (1989) to explain the superoutburst phenomenon of SU UMa stars. Recent Kepler observations of one SU UMa star, V1504 Cyg, have dramatically demonstrated that the superoutburst phenomenon of the SU UMa stars is explained by the thermal-tidal instability model.
SOFIA: A Promising Resource for Future Nova Studies
NASA Astrophysics Data System (ADS)
Helton, L. A.; Sofia Science Team
2014-12-01
The Stratospheric Observatory for Infrared Astronomy (SOFIA) is a 2.5-m telescope carried on board a Boeing 747-SP aircraft. Optimized for observations from infrared through sub-mm wavelengths, SOFIA observes from an altitude of 37,000 - 45,000 feet, above 99% of the atmospheric water vapor. The Observatory's complement of instruments possesses a broad range of capabilities, many of which are especially well suited for observations of classical novae, recurrent novae, and other cataclysmic variables. Here we present a selection of the instruments available on board SOFIA that may prove to be very useful for future novae studies.
MASTER OT J072007.30+451611.6: Cataclysmic Variable with an Extreme Hot Spot
NASA Astrophysics Data System (ADS)
Denisenko, D.
2018-05-01
MASTER team has reported an unusual object MASTER OT J072007.30+451611.6 in ATel #11620 (T. Pogrosheva et al.). The object was observed at 17.0-17.2m during 9 minutes from 22:15:26 to 22:24:30 UT on 2018-04-26, but was below the detection limit (18.8m) 45 minutes before the first positive observation and 43 minutes after the last one. As noted by S. Otero in AAVSO VSX entry, MASTER OT J072007.30+451611.6 has an X-ray counterpart XMMSL2 J072007.4+451615.
On Magnetic Dynamos in Thin Accretion Disks around Compact and Young Stars
NASA Technical Reports Server (NTRS)
Stepinski, T. F.
1993-01-01
A variety of geometrically thin accretion disks commonly associated with such astronomical objects as X-ray binaries, cataclysmic variables, and protostars are likely to be seats of MHD dynamo actions. Thin disk geometry and the particular physical environment make accretion disk dynamos different from stellar, planetary, or even galactic dynamos. We discuss those particular features of disk dynamos with emphasis on the difference between protoplanetary disk dynamos and those associated with compact stars. We then describe normal mode solutions for thin disk dynamos and discuss implications for the dynamical behavior of dynamo-magnetized accretion disks.
Busschaert, Cedric; Scherrens, Anne-Lore; De Bourdeaudhuij, Ilse; Cardon, Greet; Van Cauwenberg, Jelle; De Cocker, Katrien
2016-01-01
Introduction Knowledge about variables associated with context-specific sitting time in older adults is limited. Therefore, this study explored cross-sectional and longitudinal associations of socio-demographic, social-cognitive, physical-environmental and health-related variables with sitting during TV viewing, computer use and motorized transport in older adults. Methods A sample of Belgian older adults completed structured interviews on context-specific sitting time and associated variables using a longitudinal study design. Objective measurements of grip strength and physical performance were also completed. Complete baseline data were available of 258 participants (73.98±6.16 years) of which 229 participants remained in the study at one year follow-up (retention rate: 91.60%). Cross-sectional correlates (baseline data) and longitudinal predictors (change-scores in relation with change in sitting time) were explored through multiple linear regression analyses. Results Per context-specific sitting time, most of the cross-sectional correlates differed from the longitudinal predictors. Increases over time in enjoyment of watching TV (+one unit), encouragement of partner to watch less TV (+one unit) and TV time of partner (+30.0 min/day) were associated with respectively 9.1 min/day (p<0.001), 16.0 min/day (p<0.001) and 12.0 min/day (p<0.001) more sitting during TV viewing at follow-up. Increases over time in enjoyment of using a computer (+one unit), the number of smartphones and tablets (+1) and computer use of the partner (+30.0 min/day) were associated with respectively 5.5 min/day (p < .01), 10.4 min/day (p < .05) and 3.0 min/day (p < .05) more sitting during computer use at follow-up. An increase over time in self-efficacy regarding taking a bicycle or walking was associated with 2.9 min/day (p < .05) less sitting during motorized transport at follow-up. Conclusions The results stressed the importance of looking at separate contexts of sitting. Further, the results highlighted the importance of longitudinal research in order to reveal which changes in particular variables predicted changes in context-specific sitting time. Variables at the social-cognitive level were most frequently related to context-specific sitting. PMID:27997603
Ivory, James D; Magee, Robert G
2009-06-01
Portable media consoles are becoming extremely popular devices for viewing a number of different types of media content, both for entertainment and for educational purposes. Given the increasingly heavy use of portable consoles as an alternative to traditional television-style monitors, it is important to investigate how physiological and psychological effects of portable consoles may differ from those of television-based consoles, because such differences in physiological and psychological responses may precipitate differences in the delivered content's effectiveness. Because portable consoles are popular as a delivery system for multiple types of media content, such as movies and video games, it is also important to investigate whether differences between the effects of portable and television-based consoles are consistent across multiple types of media. This article reports a 2 x 2 (console: portable or television-based x medium: video game or movie) mixed factorial design experiment with physiological arousal and self-reported flow experience as dependent variables, designed to explore whether console type affects media experiences and whether these effects are consistent across different media. Results indicate that portable media consoles evoke lower levels of physiological arousal and flow experience and that this effect is consistent for both video games and movies. These findings suggest that even though portable media consoles are often convenient compared to television-based consoles, the convenience may come at a cost in terms of the user experience.
Harnessing Youth and Young Adult Culture: Improving the Reach and Engagement of the truth® Campaign.
Hair, Elizabeth; Pitzer, Lindsay; Bennett, Morgane; Halenar, Michael; Rath, Jessica; Cantrell, Jennifer; Dorrler, Nicole; Asche, Eric; Vallone, Donna
2017-07-01
The national youth and young adult tobacco prevention mass media campaign, truth®, relaunched in 2014 with the goal of creating "the generation that ends smoking." The objective of this study was to assess whether the strategy of airing truth ads during popular, culturally relevant televised events was associated with higher ad and brand awareness and increases in social media engagement. Awareness of six truth advertisements that aired during popular television events and self-reported social media engagement were assessed via cross-sectional online surveys of youth and young adults aged 15-21 years. Social engagement was also measured using separate Twitter and YouTube metrics. Logistic regression models predicted self-reported social engagement and any ad awareness, and a negative binomial regression predicted the total social media engagement across digital platforms. The study found that viewing a popular televised event was associated with higher odds of ad awareness and social engagement. The results also indicate that levels of social media engagement for an event period are greater than for a nonevent period. The findings demonstrate that premiering advertisements during a popular, culturally relevant televised event is associated with higher awareness of truth ads and increased social engagement related to the campaign, controlling for variables that might also influence the response to campaign messages.
NASA Technical Reports Server (NTRS)
Thorstensen, John R.; Ringwald, F. A.; Wade, Richard A.; Schmidt, Gary D.; Norsworthy, Jane E.
1991-01-01
This paper reports extensive optical observations on the PG0027 + 260 binary, carried out on August 1984 with the 1.3 McGraw-Hill telescope and Mark II spectrometer at Michigan-Dartmouth-MIT Observatory on Kitt Peak. It is shown that this object is an eclipsing novalike variable with an orbital period of 3.51 hr. The PG0027 + 260 displays several unexplained phenomena which are remarkably similar to those of the SW Sex, DW UMa, and V1315 Aql, which are eclipsing novalike stars with periods between 3 and 4 hrs. The eclipse of the PG0027 + 260 is modeled, and it is shown that, while the mean eclipse light curve is easy to match, there is no simple explanation for the variable depth.
A transient radio jet in an erupting dwarf nova.
Körding, Elmar; Rupen, Michael; Knigge, Christian; Fender, Rob; Dhawan, Vivek; Templeton, Matthew; Muxlow, Tom
2008-06-06
Astrophysical jets seem to occur in nearly all types of accreting objects, from supermassive black holes to young stellar objects. On the basis of x-ray binaries, a unified scenario describing the disc/jet coupling has evolved and been extended to many accreting objects. The only major exceptions are thought to be cataclysmic variables: Dwarf novae, weakly accreting white dwarfs, show similar outburst behavior to x-ray binaries, but no jet has yet been detected. Here we present radio observations of a dwarf nova in outburst showing variable flat-spectrum radio emission that is best explained as synchrotron emission originating in a transient jet. Both the inferred jet power and the relation to the outburst cycle are analogous to those seen in x-ray binaries, suggesting that the disc/jet coupling mechanism is ubiquitous.
Qin, Chun-Yan; Zhou, Jin; Cao, Yong; Zhang, Yong; Hughes, Robert M; Wang, Bei-Xin
2014-09-01
Aquatic organisms' tolerance to water pollution is widely used to monitor and assess freshwater ecosystem health. Tolerance values (TVs) estimated based on statistical analyses of species-environment relationships are more objective than those assigned by expert opinion. Region-specific TVs are the basis for developing accurate bioassessment metrics particularly in developing countries, where both aquatic biota and their responses to human disturbances have been poorly documented. We used principal component analysis to derive a synthetic gradient for four stressor variables (total nitrogen, total phosphorus, dissolved oxygen, and % silt) based on 286 sampling sites in the Taihu Lake and Qiantang River basins (Yangtze River Delta), China. We used the scores of taxa on the first principal component (PC1), which explained 49.8% of the variance, to estimate the tolerance values (TV(r)) of 163 macroinvertebrates taxa that were collected from at least 20 sites, 81 of which were not included in the Hilsenhoff TV lists (TV(h)) of 1987. All estimates were scaled into the range of 1-10 as in TV(h). Of all the taxa with different TVs, 46.3% of TV(r) were lower and 52.4% were higher than TV(h). TV(r) were significantly (p < 0.01, Fig. 2), but weakly (r(2) = 0.34), correlated with TVh. Seven biotic metrics based on TVr were more strongly correlated with the main stressors and were more effective at discriminating references sites from impacted sites than those based on TV(h). Our results highlight the importance of developing region-specific TVs for macroinvertebrate-based bioassessment and to facilitate assessment of streams in China, particularly in the Yangtze River Delta.
Multiwavelength study of RX J2015.6+3711: a magnetic cataclysmic variable with a 2-h spin period
NASA Astrophysics Data System (ADS)
Coti Zelati, F.; Rea, N.; Campana, S.; de Martino, D.; Papitto, A.; Safi-Harb, S.; Torres, D. F.
2016-02-01
The X-ray source RX J2015.6+3711 was discovered by ROSAT in 1996 and recently proposed to be a cataclysmic variable (CV). Here, we report on an XMM-Newton observation of RX J2015.6+3711 performed in 2014, where we detected a coherent X-ray modulation at a period of 7196 ± 11 s and discovered other significant (>6σ) small-amplitude periodicities which we interpret as the CV spin period and the sidebands of a possible ˜12-h periodicity, respectively. The 0.3-10 keV spectrum can be described by a power law (Γ = 1.15 ± 0.04) with a complex absorption pattern, a broad emission feature at 6.60 ± 0.01 keV, and an unabsorbed flux of (3.16 ± 0.05) × 10-12 erg cm-2 s-1. We observed a significant spectral variability along the spin phase, which can be ascribed mainly to changes in the density of a partial absorber and the power law normalization. Archival X-ray observations carried out by the Chandra satellite, and two simultaneous X-ray and UV/optical pointings with Swift, revealed a gradual fading of the source in the soft X-rays over the last 13 yr, and a rather stable X-ray-to-optical flux ratio (FX/FV ≈ 1.4-1.7). Based on all these properties, we identify this source with a magnetic CV, most probably of the intermediate polar type. The 2-h spin period makes RX J2015.6+3711, the second slowest rotator of the class, after RX J0524+4244 (`Paloma'; Pspin ˜ 2.3 h). Although we cannot unambiguously establish the true orbital period with these observations, RX J2015.6+3711 appears to be a key system in the evolution of magnetic CVs.
Variable features on Mars - Preliminary Mariner 9 television results.
NASA Technical Reports Server (NTRS)
Sagan, C.; Veverka, J.; Fox, P.; Dubisch, R.; Lederberg, J.; Levinthal, E.; Quam, L.; Tucker, R.; Pollack, J. B.; Smith, B. A.
1972-01-01
Systematic Mariner 9 photography of a range of Martian surface features, observed with all three photometric angles approximately invariant, reveals three general categories of albedo variations: (1) an essentially uniform contrast enhancement due to the dissipation of the dust storm; (2) the appearance of splotches, irregular dark markings at least partially related to topography; and (3) the development of both bright and dark linear streaks, generally emanating from craters. Some splotches and streaks vary on characteristic timescales of about two weeks; they have characteristic dimensions of kilometers to tens of kilometers. The morphology and variability of streaks and splotches, and the resolution of at least one splotch into an extensive dune system, implicate windblown dust as the principal agent of Martian albedo differences and variability.
Wijndaele, Katrien; Brage, Søren; Besson, Hervé; Khaw, Kay-Tee; Sharp, Stephen J.; Luben, Robert; Bhaniani, Amit; Wareham, Nicholas J.; Ekelund, Ulf
2011-01-01
Background Although television viewing time is detrimentally associated with intermediate cardiovascular risk factors, the relationship with incident total (i.e. combined fatal and non-fatal) cardiovascular disease (CVD), non-fatal CVD and coronary heart disease is largely unknown. This study examined whether television viewing time is associated with these three outcomes, independently of physical activity energy expenditure and other confounding variables. Methodology/Principal Findings A population-based cohort of 12,608 men and women (aged 61.4±9.0), free from stroke, myocardial infarction and cancer at baseline in 1998–2000 were followed up until 2007 (6.9±1.9 years). Participants self-reported education, smoking, alcohol use, antihypertensive, lipid lowering and antidepressant medication, disease history, total energy intake, sleep duration, physical activity and television viewing. BMI, waist circumference, blood pressure, triglycerides, HDL cholesterol and glycated haemoglobin (HbA1c) were measured by standardized procedures; a clustered metabolic risk score was constructed. Every one hour/day increase in television viewing was associated with an increased hazard for total (HR = 1.06, 95%CI = 1.03–1.08; 2,620 cases), non-fatal CVD (HR = 1.06, 95%CI = 1.03–1.09; 2,134 cases), and coronary heart disease (HR = 1.08, 95%CI = 1.03–1.13; 940 cases), independent of gender, age, education, smoking, alcohol, medication, diabetes status, CVD family history, sleep duration and physical activity energy expenditure. Energy intake, BMI, waist circumference, blood pressure, triglycerides, HDL cholesterol, HbA1c and the clustered metabolic risk score only partially mediated these associations. Conclusions These results indicate that the most prevalent leisure time (sedentary) behaviour, television viewing, independently contributes to increased CVD risk. Recommendations on reducing television viewing time should be considered. PMID:21647437
Television and music video exposure and adolescent 'alcopop' use.
Van den Bulck, Jan; Beullens, Kathleen; Mulder, Joost
2006-01-01
Alcohol abuse among adolescents is a cause for concern. Around 1995 alcopops (sweetened alcoholic drinks) entered the scene and caused even more concern. Many fear that the sweet taste makes is easier to start drinking for those not yet used to drinking alcohol and the marketing appears aimed at adolescents. Because alcohol use has been linked to television viewing in general and music video viewing in particular this article examined whether a relationship existed between television and music video exposure and the consumption of alcopops. Data were collected with a questionnaire focused on television exposure and alcohol behavior. Respondents were a random sample of 2,546 first- and fourth year schoolchildren of Flanders, the Dutch speaking region of Belgium (60% of the Belgian population). Self reported general TV viewing, music video exposure and drinking of alcopops at home and/or while going out were measured. 68.4% of the respondents watched music videos at least several times a week. The odds of being an alcopop drinker at home increased by 196% for those, who watched music videos at least several times a week (OR = 1.961). For each additional hour of TV viewed per day, the respondents were 17% more likely to be drinkers of altopops at home (OR = 1.169). The odds of being an alcopop drinker, when going out increased by 239% for those who watched music videos at least several times a week (OR = 2.394). For each additional hour of TV viewed per day, the respondents were 19% more likely to be drinkers of alcopops when going out (OR = 1.186). These findings suggest that there is an association between music video exposure and use of alcopops not explained by overall exposure to television. This relationship merits further attention as it is a better predictor of alcopop use, than the control variables and overall TV viewing.
History of the Terminal Cataclysm Concept: A Cataclysm That Never Happened?
NASA Astrophysics Data System (ADS)
Hartmann, William K.
2014-11-01
The “terminal cataclysm” (or “late heavy bombardment”) concept of the last 40 years exhibits curious epistemology, with changing definitions and inconsistent evidence.Pre-Apollo evidence showed that the impact rate prior to ~3.5 Ga ago averaged ~150x the post-mare rate [1]. In 1973-4, Tera et al. [2,3] introduced the term “terminal cataclysm,” widespread metamorphism ~3.9 Ga ago, possibly caused by the Imbrium impact [3, p.15], or more likely by “formation of several major basins [in a] short time interval (less than 0.2AE)” [3, p.18]. In 1990, Ryder [4] reported a strong spike in ages for Apollo impact melt rocks ~3.8-4.0 Ga ago, and proposed this as proof that a Moon-wide cataclysmic bombardment occurred at that time, with no earlier cratering. Three inconsistencies soon appeared. (1) In 2002, Cohen et al. [5, also 2002 & 2005] dated lunar meteorite clasts (aiming at non-Apollo lunar regions) and found no spike or anomaly at 3.9 Ga. (Yet they inferred “support for the lunar cataclysm hypothesis.”) (2) The Nice model in early 2000s predicted many planetesimals scattered from the outer to the inner Solar System [6], with a plausible (unconstrained) date of 3.9 Ga - but asteroidal meteorite impact melt clasts (like lunar meteorites) show no spike at 3.9. (3) Meanwhile, reports of pre-4.0 impact melts have increased among upland breccia clasts. Nice and Grand Tack modelers have introduced “sawteeth” spikes before 4.0 and gradual declines after 3.8 (both had been proposed earlier), thus softening the “cataclysm” spike. A 2014 model by Marchi, Bottke, Morbidelli, Kring, et al. [7] illustrates a curve of impact flux vs. time, 4.4 to 3.5 Ga, showing no spike at 3.9 Ga - signaling a possible demise of the terminal cataclysm hypothesis. [1] Hartmann W.K. 1966. Icarus 5, 406-418[2] Tera F. et al. 1973. LPSC abstract, p. 723[3] Tera F. et al. 1974. EPSK 22, 1-21[4] Ryder G. 1990. EOS 71, 313[5] Cohen B., Swindle T., Kring D. 2000. Science 290, 1754-1756[6] Morbidelli A., Bottke W. 2006. 1st Int’l Conf. on Impact Cratering in the Solar System (Noordwijk: ESTEC), abstract[7] Marchi S. et al. 2014. Nature 511, 578-582
Effect of handling characteristics on minimum time cornering with torque vectoring
NASA Astrophysics Data System (ADS)
Smith, E. N.; Velenis, E.; Tavernini, D.; Cao, D.
2018-02-01
In this paper, the effect of both passive and actively-modified vehicle handling characteristics on minimum time manoeuvring for vehicles with 4-wheel torque vectoring (TV) capability is studied. First, a baseline optimal TV strategy is sought, independent of any causal control law. An optimal control problem (OCP) is initially formulated considering 4 independent wheel torque inputs, together with the steering angle rate, as the control variables. Using this formulation, the performance benefit using TV against an electric drive train with a fixed torque distribution, is demonstrated. The sensitivity of TV-controlled manoeuvre time to the passive understeer gradient of the vehicle is then studied. A second formulation of the OCP is introduced where a closed-loop TV controller is incorporated into the system dynamics of the OCP. This formulation allows the effect of actively modifying a vehicle's handling characteristic via TV on its minimum time cornering performance of the vehicle to be assessed. In particular, the effect of the target understeer gradient as the key tuning parameter of the literature-standard steady-state linear single-track model yaw rate reference is analysed.
Kaub-Wittemer, Dagmar; Steinbüchel, Nicole von; Wasner, Maria; Laier-Groeneveld, Gerhard; Borasio, Gian Domenico
2003-10-01
Non-invasive ventilation (NIV) is an efficient palliative measure for symptoms of chronic hypoventilation in patients with amyotrophic lateral sclerosis (ALS), and can also lengthen survival. A subset of ALS patients undergoes tracheostomy ventilation (TV) for life prolongation. We investigated the quality of life (QOL) and psychosocial situation of 52 home ventilated ALS patients and their caregivers. The battery included sociodemographic, generic, and disease-specific variables, as well as the Profile of Mood States and the Munich Quality of Life Dimensions List. Data were compared between the NIV (n=32) and the TV (n=21) groups. Mean ventilation time was 14 months for NIV and 35 months for TV. Eighty-one percent of TV patients had been tracheotomized without informed consent. The data show a good overall QOL for both NIV and TV patients, but a very high burden of care for TV caregivers, 30% of whom rated their own QOL lower than their patient's QOL. Sexuality was an important issue. Thus, any assessment of QOL in a home palliative care situation should include the primary caregivers.
Metabolic risk and television time in adolescent females.
Machado-Rodrigues, Aristides M; Leite, Neiva; Coelho-e-Silva, Manuel J; Enes, Fernando; Fernandes, Rômulo; Mascarenhas, Luís P G; Boguszewski, Margaret C S; Malina, Robert M
2015-02-01
A sedentary lifestyle is increasingly implicated in a negative metabolic health profile among youth. The present study examined relationships between clustered metabolic risk factors and TV viewing in female adolescents. The sample comprised 262 girls 14-17 years. Height, weight, fasting glucose, insulin, HDL cholesterol, triglycerides, and blood pressure were measured. Body mass index (BMI) was calculated. TV viewing time and moderate-to-vigorous physical activity (MVPA) were estimated from a 3-day diary. Outcome variables were normalized and expressed as Z scores which were summed into a metabolic risk score. Multiple linear regression analysis was used. TV viewing was independently associated with increased prevalence of clustered metabolic risk in girls after adjustment for several confounders (i.e., chronological age, BMI, MVPA, and parental education). The final model also indicated that lower levels of MVPA, higher BMI, and lower mother education were associated with higher metabolic risk. Increased TV viewing had an adverse effect on metabolic health of adolescent girls. The findings highlight the potential importance of preventive actions to ameliorate metabolic risk in youth which target both sedentary and physically active behaviors.
High-speed photometry of Gaia14aae: an eclipsing AM CVn that challenges formation models
NASA Astrophysics Data System (ADS)
Green, M. J.; Marsh, T. R.; Steeghs, D. T. H.; Kupfer, T.; Ashley, R. P.; Bloemen, S.; Breedt, E.; Campbell, H. C.; Chakpor, A.; Copperwheat, C. M.; Dhillon, V. S.; Hallinan, G.; Hardy, L. K.; Hermes, J. J.; Kerry, P.; Littlefair, S. P.; Milburn, J.; Parsons, S. G.; Prasert, N.; van Roestel, J.; Sahman, D. I.; Singh, N.
2018-05-01
AM CVn-type systems are ultracompact, hydrogen-deficient accreting binaries with degenerate or semidegenerate donors. The evolutionary history of these systems can be explored by constraining the properties of their donor stars. We present high-speed photometry of Gaia14aae, an AM CVn with a binary period of 49. 7 min and the first AM CVn in which the central white dwarf is fully eclipsed by the donor star. Modelling of the light curves of this system allows for the most precise measurement to date of the donor mass of an AM CVn, and relies only on geometric and well-tested physical assumptions. We find a mass ratio q = M2/M1 = 0.0287 ± 0.0020 and masses M1 = 0.87 ± 0.02 M⊙ and M2 = 0.0250 ± 0.0013 M⊙. We compare these properties to the three proposed channels for AM CVn formation. Our measured donor mass and radius do not fit with the contraction that is predicted for AM CVn donors descended from white dwarfs or helium stars at long orbital periods. The donor properties we measure fall in a region of parameter space in which systems evolved from hydrogen-dominated cataclysmic variables are expected, but such systems should show spectroscopic hydrogen, which is not seen in Gaia14aae. The evolutionary history of this system is therefore not clear. We consider a helium-burning star or an evolved cataclysmic variable to be the most likely progenitors, but both models require additional processes and/or fine-tuning to fit the data. Additionally, we calculate an updated ephemeris which corrects for an anomalous time measurement in the previously published ephemeris.
Godon, Patrick; Sion, Edward M; Balman, Şölen; Blair, William P
2017-09-01
The standard disk is often inadequate to model disk-dominated cataclysmic variables (CVs) and generates a spectrum that is bluer than the observed UV spectra. X-ray observations of these systems reveal an optically thin boundary layer (BL) expected to appear as an inner hole in the disk. Consequently, we truncate the inner disk. However, instead of removing the inner disk, we impose the no-shear boundary condition at the truncation radius, thereby lowering the disk temperature and generating a spectrum that better fits the UV data. With our modified disk, we analyze the archival UV spectra of three novalikes that cannot be fitted with standard disks. For the VY Scl systems MV Lyr and BZ Cam, we fit a hot inflated white dwarf (WD) with a cold modified disk ( [Formula: see text] ~ a few 10 -9 M ⊙ yr -1 ). For V592 Cas, the slightly modified disk ( [Formula: see text] ~ 6 × 10 -9 M ⊙ yr -1 ) completely dominates the UV. These results are consistent with Swift X-ray observations of these systems, revealing BLs merged with ADAF-like flows and/or hot coronae, where the advection of energy is likely launching an outflow and heating the WD, thereby explaining the high WD temperature in VY Scl systems. This is further supported by the fact that the X-ray hardness ratio increases with the shallowness of the UV slope in a small CV sample we examine. Furthermore, for 105 disk-dominated systems, the International Ultraviolet Explorer spectra UV slope decreases in the same order as the ratio of the X-ray flux to optical/UV flux: from SU UMa's, to U Gem's, Z Cam's, UX UMa's, and VY Scl's.
XMM-Newton studies of the supernova remnant G350.0-2.0
NASA Astrophysics Data System (ADS)
Karpova, A.; Shternin, P.; Zyuzin, D.; Danilenko, A.; Shibanov, Yu.
2016-11-01
We report the results of XMM-Newton observations of the Galactic mixed-morphology supernova remnant G350.0-2.0. Diffuse thermal X-ray emission fills the north-western part of the remnant surrounded by radio shell-like structures. We did not detect any X-ray counterpart of the latter structures, but found several bright blobs within the diffuse emission. The X-ray spectrum of the most part of the remnant can be described by a collisionally ionized plasma model VAPEC with solar abundances and a temperature of ≈0.8 keV. The solar abundances of plasma indicate that the X-ray emission comes from the shocked interstellar material. The overabundance of Fe was found in some of the bright blobs. We also analysed the brightest point-like X-ray source 1RXS J172653.4-382157 projected on the extended emission. Its spectrum is well described by the two-temperature optically thin thermal plasma model MEKAL typical for cataclysmic variable stars. The cataclysmic variable source nature is supported by the presence of a faint (g ≈ 21) optical source with non-stellar spectral energy distribution at the X-ray position of 1RXS J172653.4-382157. It was detected with the XMM-Newton optical/UV monitor in the U filter and was also found in the archival Hα and optical/near-infrared broad-band sky survey images. On the other hand, the X-ray spectrum is also described by the power law plus thermal component model typical for a rotation powered pulsar. Therefore, the pulsar interpretation of the source cannot be excluded. For this source, we derived the upper limit for the pulsed fraction of 27 per cent.
NASA Astrophysics Data System (ADS)
Brown, Shannon; Moon, Dae-Sik; Ni, Yuan Qi; Drout, Maria; Antoniadis, John; Afsariardchi, Niloufar; Cha, Sang-Mok; Lee, Yongseok
2018-06-01
We report multicolor BVI monitoring and spectroscopic classification of the dwarf nova KSP-OT-201503a. The transient was detected by the Korean Microlensing Telescope Network (KMTNet) Supernova Program (KSP) in 2015 March, reached a peak apparent magnitude V ≃ 17.3 mag from a quiescent magnitude V ≃ 22.6 mag, and lasted for approximately 17 days. Our high-cadence sampling allows us to identify distinctive phases consisting of a rapid ascent, a main outburst composed of a flat plateau followed by a gradual dimming, and a quick decline. We observe the sharp transition between the ascent phase and main outburst phase, likely related to the deceleration of the heating front as it passes through the accretion disk. These features in the light curves indicate that the outburst is outside-in. Archival data reveal the outburst history of the source, showing at least three outbursts between 2011 and 2015. These are equally separated by approximately 25 months, though we find a recurrence time as short as 189 days is compatible with the archival data. An optical spectrum obtained 701 days from outburst peak shows prominent Balmer emission lines superimposed on a blue continuum, consistent with a cataclysmic variable in quiescence. The outburst properties of KSP-OT-201503a closely resemble those of U Gem-type dwarf novae usually associated with younger, longer-period systems above the period gap of 2–3 hr observed in cataclysmic variables. This suggests that the source may be a rare U Gem-type dwarf nova with a long recurrence time, though we are unable to rule out the possibility that KSP-OT-201503a lies below the period gap.
EVOLUTION OF CATACLYSMIC VARIABLES AND RELATED BINARIES CONTAINING A WHITE DWARF
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kalomeni, B.; Rappaport, S.; Molnar, M.
We present a binary evolution study of cataclysmic variables (CVs) and related systems with white dwarf (WD) accretors, including for example, AM CVn systems, classical novae, supersoft X-ray sources (SXSs), and systems with giant donor stars. Our approach intentionally avoids the complications associated with population synthesis algorithms, thereby allowing us to present the first truly comprehensive exploration of all of the subsequent binary evolution pathways that zero-age CVs might follow (assuming fully non-conservative, Roche-lobe overflow onto an accreting WD) using the sophisticated binary stellar evolution code MESA. The grid consists of 56,000 initial models, including 14 WD accretor masses, 43more » donor-star masses (0.1–4.7 M {sub ⊙}), and 100 orbital periods. We explore evolution tracks in the orbital period and donor-mass ( P {sub orb}– M {sub don}) plane in terms of evolution dwell times, masses of the WD accretor, accretion rate, and chemical composition of the center and surface of the donor star. We report on the differences among the standard CV tracks, those with giant donor stars, and ultrashort period systems. We show where in parameter space one can expect to find SXSs, present a diagnostic to distinguish among different evolutionary paths to forming AM CVn binaries, quantify how the minimum orbital period in CVs depends on the chemical composition of the donor star, and update the P {sub orb}( M {sub wd}) relation for binaries containing WDs whose progenitors lost their envelopes via stable Roche-lobe overflow. Finally, we indicate where in the P {sub orb}– M {sub don} the accretion disks will tend to be stable against the thermal-viscous instability, and where gravitational radiation signatures may be found with LISA.« less
ORIGIN OF THE GALACTIC DIFFUSE X-RAY EMISSION: IRON K-SHELL LINE DIAGNOSTICS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nobukawa, Masayoshi; Uchiyama, Hideki; Nobukawa, Kumiko K.
This paper reports detailed K-shell line profiles of iron (Fe) and nickel (Ni) of the Galactic Center X-ray Emission (GCXE), Galactic Bulge X-ray Emission (GBXE), Galactic Ridge X-ray Emission (GRXE), magnetic Cataclysmic Variables (mCVs), non-magnetic Cataclysmic Variables (non-mCVs), and coronally Active Binaries (ABs). For the study of the origin of the GCXE, GBXE, and GRXE, the spectral analysis is focused on equivalent widths of the Fe i-K α , Fe xxv-He α , and Fe xxvi-Ly α lines. The global spectrum of the GBXE is reproduced by a combination of the mCVs, non-mCVs, and ABs spectra. On the other hand,more » the GRXE spectrum shows significant data excesses at the Fe i-K α and Fe xxv-He α line energies. This means that additional components other than mCVs, non-mCVs, and ABs are required, which have symbiotic phenomena of cold gas and very high-temperature plasma. The GCXE spectrum shows larger excesses than those found in the GRXE spectrum at all the K-shell lines of iron and nickel. Among them the largest ones are the Fe i-K α , Fe xxv-He α , Fe xxvi-Ly α , and Fe xxvi-Ly β lines. Together with the fact that the scale heights of the Fe i-K α , Fe xxv-He α , and Fe xxvi-Ly α lines are similar to that of the central molecular zone (CMZ), the excess components would be related to high-energy activity in the extreme envelopment of the CMZ.« less
A spectroscopic search for faint secondaries in cataclysmic variables
NASA Astrophysics Data System (ADS)
Vande Putte, D.; Smith, Robert Connon; Hawkins, N. A.; Martin, J. S.
2003-06-01
The secondary in cataclysmic variables (CVs) is usually detected by cross-correlation of the CV spectrum with that of a K or M dwarf template, to produce a radial velocity curve. Although this method has demonstrated its power, it has its limits in the case of noisy spectra, such as are found when the secondary is faint. A method of coadding spectra, called skew mapping, has been proposed in the past. Gradually, examples of its application are being published; none the less, so far no journal article has described the technique in detail. To answer this need, this paper explores in detail the capabilities of skew mapping when determining the amplitude of the radial velocity for faint secondaries. It demonstrates the power of the method over techniques that are more conventional, when the signal-to-noise ratio is poor. The paper suggests an approach to assessing the quality of results. This leads in the case of the investigated objects to a first tier of results, where we find K2= 127 +/- 23 km s-1 for SY Cnc, K2= 144 +/- 18 km s-1 for RW Sex and K2= 262 +/- 14 km s-1 for UX UMa. These we believe to be the first direct determinations of K2 for these objects. Furthermore, we also obtain K2= 263 +/- 30 km s-1 for RW Tri, close to a skew mapping result obtained elsewhere. In the first three cases, we use these results to derive the mass of the white dwarf companion. A second tier of results includes UU Aqr, EX Hya and LX Ser, for which we propose more tentative values of K2. Clear failures of the method are also discussed (EF Eri, VV Pup and SW Sex).
Evolution of Cataclysmic Variables and Related Binaries Containing a White Dwarf
NASA Astrophysics Data System (ADS)
Kalomeni, B.; Nelson, L.; Rappaport, S.; Molnar, M.; Quintin, J.; Yakut, K.
2016-12-01
We present a binary evolution study of cataclysmic variables (CVs) and related systems with white dwarf (WD) accretors, including for example, AM CVn systems, classical novae, supersoft X-ray sources (SXSs), and systems with giant donor stars. Our approach intentionally avoids the complications associated with population synthesis algorithms, thereby allowing us to present the first truly comprehensive exploration of all of the subsequent binary evolution pathways that zero-age CVs might follow (assuming fully non-conservative, Roche-lobe overflow onto an accreting WD) using the sophisticated binary stellar evolution code MESA. The grid consists of 56,000 initial models, including 14 WD accretor masses, 43 donor-star masses (0.1-4.7 M ⊙), and 100 orbital periods. We explore evolution tracks in the orbital period and donor-mass (P orb-M don) plane in terms of evolution dwell times, masses of the WD accretor, accretion rate, and chemical composition of the center and surface of the donor star. We report on the differences among the standard CV tracks, those with giant donor stars, and ultrashort period systems. We show where in parameter space one can expect to find SXSs, present a diagnostic to distinguish among different evolutionary paths to forming AM CVn binaries, quantify how the minimum orbital period in CVs depends on the chemical composition of the donor star, and update the P orb(M wd) relation for binaries containing WDs whose progenitors lost their envelopes via stable Roche-lobe overflow. Finally, we indicate where in the P orb-M don the accretion disks will tend to be stable against the thermal-viscous instability, and where gravitational radiation signatures may be found with LISA.
Analysis of cataclysmic variable GSC02197-00886 evolution
NASA Astrophysics Data System (ADS)
Mitrofanova, A. A.; Borisov, N. V.; Shimansky, V. V.
2014-01-01
We present the spectral analysis of the physical state and evolution of the WZSge-type cataclysmic variable GSC02197-00886. The spectra of the system, covering the total orbital period at the time of the outburst on May 8, 2010, at the late relaxation stage, and in the quiescent state, were obtained at the SAO RAS 6-m BTA telescope in 2010-2012. From the absorption and emission HI, He I, and Fe II lines, we have determined the radial velocities for all the nights of observations and constructed the maps of Doppler tomography for the quiescent state. It was found that during the outburst the spectra of the object were formed in an optically thick accretion disk with an effective temperature of T eff ≈ 45 000 K and in a hotter boundary layer. During the relaxation of the system, the accretion disk gradually became optically thinner in the continuum and in the emission lines. In the quiescent state (July 2012), the continuous spectrum was dominated by the radiation of the cooling white dwarf with T eff = 18 000 K. The emission lines are formed on the surface of the cool star by the X-ray irradiation of the 1RXSJ213807.1+261958 source. We propose a method for determining the parameters of the white dwarf, based on the numerical modeling of the system spectra in the quiescent state and their comparison with the observed spectra. It is shown that the effective temperature of white dwarf has decreased by Δ T eff = 6000 K during the relaxation from August 2010 to July 2012. We have obtained a set of parameters for GSC02197-00886 and shown their good agreement with the average parameters of the W Z Sge-type systems, presented in the literature.
Does alcohol advertising promote adolescent drinking? Results from a longitudinal assessment.
Ellickson, Phyllis L; Collins, Rebecca L; Hambarsoomians, Katrin; McCaffrey, Daniel F
2005-02-01
To examine the relationship between exposure to different forms of alcohol advertising and subsequent drinking among US adolescents and assess whether exposure to an alcohol and drug prevention program mitigates any such relationship. Regression models with multiple control variables examined the relationship between exposure to alcohol advertising in grade 8 and grade 9 drinking for two groups of South Dakotan adolescents: (1) seventh-grade non-drinkers (n = 1206) and (2) seventh-grade drinkers (n = 1905). Interactions between the intervention program and the significant advertising predictors were tested. Forty-one middle schools in South Dakota, USA. A total of 3111 seventh-graders followed through grade 9. Advertising variables were constructed for four types of alcohol advertising-television, in-store displays, magazines and concession stands. Other predictors tested included measures tapping social influences, social bonds, problem behavior, alcohol beliefs, television exposure and demographics. For seventh-grade non-drinkers, exposure to in-store beer displays predicted drinking onset by grade 9; for seventh-grade drinkers, exposure to magazines with alcohol advertisements and to beer concession stands at sports or music events predicted frequency of grade 9 drinking. Although exposure to television beer advertising had a significant bivariate relationship with alcohol use for grade 7 non-drinkers, it was not a significant predictor of drinking for either group in multivariate analyses. Participation in the prevention program, ALERT Plus, reduced future drinking for both groups and counteracted the effect of in-store beer displays. Several forms of alcohol advertising predict adolescent drinking; which sources dominate depends on the child's prior experience with alcohol. Alcohol prevention programs and policies should help children counter alcohol advertising from multiple sources and limit exposure to these sources.
Playing a violent television game affects heart rate variability.
Ivarsson, Malena; Anderson, Martin; Akerstedt, Torbjörn; Lindblad, Frank
2009-01-01
To investigate how playing a violent/nonviolent television game during the evening affects sympathetic and parasympathetic reactions during and after playing as well as sleep quality during the night after playing. In total, 19 boys, 12-15 years of age, played television games on two occasions in their homes and participated once without gaming. Heart rate, heart rate variability (HRV) and physical activity were measured during gaming/participating and the night to follow using a portable combined heart rate and movement sensor. A sleep diary and questionnaires about gaming experiences and session-specific experiences were filled in. Criteria for Selection of Games: Violent game involves/rewards direct physical violence (no handguns) against another person, and nonviolent game involves/rewards no violence; same game design ('third-person game'); conducted in the same manner; no differences concerning motor activity; similar sound and light effects; no sexual content, violence against women or racial overtones. During violent (vs. nonviolent) gaming, there was significantly higher activity of the very low frequency component of the HRV and total power. During the night after playing, very low frequency, low frequency and high frequency components were significantly higher during the violent (vs. nonviolent) condition, just as total power. There were no significant differences between the three conditions (violent/nonviolent/no gaming) with respect to an index reflecting subjectively perceived sleep difficulties. Nor was there any difference between violent and nonviolent condition for any single sleep item. Violent gaming induces different autonomic responses in boys compared to nonviolent gaming--during playing and during the following night--suggesting different emotional responses. Subjectively perceived sleep quality is not influenced after a single gaming experience. Future studies should address the development of the autonomic balance after gaming over longer time than a night, physiological adaptation to frequent gaming and potential gender differences.
Tsiros, Margarita D; Samaras, Michelle G; Coates, Alison M; Olds, Timothy
2017-11-01
To investigate associations between aspects of time use and health-related quality of life (HRQoL) in youth. 239 obese and healthy-weight 10- to 13-year-old Australian children completed the Pediatric Quality of Life Inventory (PedsQL™) quantifying their health-related quality of life. Time use was evaluated over four days using the Multimedia Activity Recall for Children and Adolescents (MARCA), a validated 24 h recall tool. The average number of minutes/day spent in physical activity (divided into sport, active transport and play), screen time (divided into television, videogames and computer use), and sleep were calculated. Percent fat was measured using dual-energy X-ray absorptiometry, Tanner stage by self-report, and household income by parental report. Sex-stratified analysis was conducted using Partial Least Squares regression, with percent fat, Tanner stage, household income, and use-of-time as the independent variables, and PedsQL™ total, physical and psychosocial subscale scores as the dependent variables. For boys, the most important predictors of HRQoL were percent fat (negative), videogames (negative), sport (positive), and Tanner stage (negative). For girls, the significant predictors were percent fat (negative), television (negative), sport (positive), active transport (negative), and household income (positive). While body fat was the most significant correlate of HRQoL, sport was independently associated with better HRQoL, and television and videogames with poorer HRQoL. Thus, parents and clinicians should be mindful that not all physical activity and screen-based behaviours have equivocal relationships with children's HRQoL. Prospective research is needed to confirm causation and to inform current activity guidelines.
EMG normalization to study muscle activation in cycling.
Rouffet, David M; Hautier, Christophe A
2008-10-01
The value of electromyography (EMG) is sensitive to many physiological and non-physiological factors. The purpose of the present study was to determine if the torque-velocity test (T-V) can be used to normalize EMG signals into a framework of biological significance. Peak EMG amplitude of gluteus maximus (GMAX), vastus lateralis (VL), rectus femoris (RF), biceps femoris long head (BF), gastrocnemius medialis (GAS) and soleus (SOL) was calculated for nine subjects during isometric maximal voluntary contractions (IMVC) and torque-velocity bicycling tests (T-V). Then, the reference EMG signals obtained from IMVC and T-V bicycling tests were used to normalize the amplitude of the EMG signals collected for 15 different submaximal pedaling conditions. The results of this study showed that the repeatability of the measurements between IMVC (from 10% to 23%) and T-V (from 8% to 20%) was comparable. The amplitude of the peak EMG of VL was 99+/-43% higher (p<0.001) when measured during T-V. Moreover, the inter-individual variability of the EMG patterns calculated for submaximal cycling exercises differed significantly when using T-V bicycling normalization method (GMAX: 0.33+/-0.16 vs. 1.09+/-0.04, VL: 0.07+/-0.02 vs. 0.64+/-0.14, SOL: 0.07+/-0.03 vs. 1.00+/-0.07, RF: 1.21+/-0.20 vs. 0.92+/-0.13, BF: 1.47+/-0.47 vs. 0.84+/-0.11). It was concluded that T-V bicycling test offers the advantage to be less time and energy-consuming and to be as repeatable as IMVC tests to measure peak EMG amplitude. Furthermore, this normalization method avoids the impact of non-physiological factors on the amplitude of the EMG signals so that it allows quantifying better the activation level of lower limb muscles and the variability of the EMG patterns during submaximal bicycling exercises.
ERIC Educational Resources Information Center
Hendon, Donald W.; And Others
To learn if differences in age, intelligence, and sex account for differences in children's recall of TV commercials and in the degree of insistence with which they request that the advertised product be purchased, 54 gifted, 71 normal, and 53 educable mentally retarded children of both sexes were questioned after viewing commercials for breakfast…
Little, Matthew; Humphries, Sally; Patel, Kirit; Dewey, Cate
2016-01-01
Overweight, obesity, and related chronic diseases are becoming serious public health concerns in rural areas of India. Compounded with the existing issue of underweight, such concerns expose the double burden of disease and may put stress on rural healthcare. The purpose of this article was to present the prevalence and factors associated with underweight, overweight, and obesity in an area of rural south India. During 2013 and 2014, a random sample of adults aged 20-80 years were selected for participation in a cross-sectional study that collected information on diet (using a food frequency questionnaire), physical activity (using the Global Physical Activity Questionnaire), socioeconomic position (using a wealth index), rurality (using the MSU rurality index), education, and a variety of descriptive factors. BMI was measured using standard techniques. Using a multivariate linear regression analysis and multivariate logistic regression analyses, we examined associations between BMI, overweight, obesity, and underweight, and all potential risk factors included in the survey. Age and sex-adjusted prevalence of overweight, obesity class I, and obesity class II were 14.9, 16.1, and 3.3 % respectively. Prevalence of underweight was 22.7 %. The following variables were associated with higher BMI and/or increased odds of overweight, obesity class I, and/or obesity class II: Low physical activity, high wealth index, no livestock, low animal fat consumption, high n-6 polyunsaturated fat consumption, television ownership, time spent watching television, low rurality index, and high caste. The following variables were associated with increased odds of underweight: low wealth index, high rurality index, and low intake of n-6 PUFAs. Underweight, overweight, and obesity are prevalent in rural regions of southern India, indicating a village-level dual burden. A variety of variables are associated with these conditions, including physical activity, socioeconomic position, rurality, television use, and diet. To address the both underweight and obesity, policymakers must simultaneously focus on encouraging positive behaviour through education and addressing society-level risk factors that inhibit individuals from achieving optimal health.
Color visualization for fluid flow prediction
NASA Technical Reports Server (NTRS)
Smith, R. E.; Speray, D. E.
1982-01-01
High-resolution raster scan color graphics allow variables to be presented as a continuum, in a color-coded picture that is referenced to a geometry such as a flow field grid or a boundary surface. Software is used to map a scalar variable such as pressure or temperature, defined on a two-dimensional slice of a flow field. The geometric shape is preserved in the resulting picture, and the relative magnitude of the variable is color-coded onto the geometric shape. The primary numerical process for color coding is an efficient search along a raster scan line to locate the quadrilteral block in the grid that bounds each pixel on the line. Tension spline interpolation is performed relative to the grid for specific values of the scalar variable, which is then color coded. When all pixels for the field of view are color-defined, a picture is played back from a memory device onto a television screen.
Associations between parenting, media use, cumulative risk, and children's executive functioning.
Linebarger, Deborah L; Barr, Rachel; Lapierre, Matthew A; Piotrowski, Jessica T
2014-01-01
This study was designed to examine how parenting style, media exposure, and cumulative risk were associated with executive functioning (EF) during early childhood. A nationally representative group of US parents/caregivers (N = 1156) with 1 child between 2 and 8 years participated in a telephone survey. Parents were asked to report on their child's exposure to television, music, and book reading through a 24-hour time diary. Parents also reported a host of demographic and parenting variables as well as questions on their child's EF. Separate multiple regressions for preschool (2-5 years) and school-aged (6-8 years) children grouped by cumulative risk were conducted. Parenting style moderated the risks of exposure to background television on EF for high-risk preschool-age children. Educational TV exposure served as a buffer for high-risk school-aged children. Cumulative risk, age, and parenting quality interacted with a number of the exposure effects. The study showed a complex pattern of associations between cumulative risk, parenting, and media exposure with EF during early childhood. Consistent with the American Academy of Pediatrics, these findings support the recommendation that background television should be turned off when a child is in the room and suggest that exposure to high-quality content across multiple media platforms may be beneficial.
OV Bootis: Forty Nights of World-Wide Photometry (Abstract)
NASA Astrophysics Data System (ADS)
Patterson, J.; de Miguel, E.; Barret, D.; Brincat, S.; Boardman, J., Jr.; Buczynski, D.; Campbell, T.; Cejudo, D.; Cook, L.; Cook, M. J.; Collins, D.; Cooney, W.; Dubois, F.; Dvorak, S.; Halpern, J. P.; Kroes, A. J.; Lemay, D.; Licchelli, D.; Mankel, D.; Marshall, M.; Novak, R.; Oksanen, A.; Roberts, G.; Seargeant, J.; Sears, H.; Silcox, A.; Slauson, D.; Stone, G.; Thorstensen, J. R.; Ulowetz, J.; Vanmunster, T.; Wallgren, J.; Wood, M.
2017-12-01
(Abstract only) Among the 1000 known cataclysmic variables, only one appears to belong to the "Galactic halo"-the Population II stars. We report round-the-world photometry of this star (OV Boo) during March-April 2017, when it staged its first certified dwarf-nova outburst. The star is remarkable for its short binary period (66 minutes), high proper motion, metal-poor composition, substellar secondary, sharp white-dwarf eclipses, and nonradial pulsations. Something for everybody - and it even had the good manners to erupt in northern springtime, when it transits near local midnight. Move over, SS Cyg and WZ Sge; there's a new celebrity in town!
1RXS J184542.4+483134 is a new eclipsing polar
NASA Astrophysics Data System (ADS)
Pavlenko, E.; Sokolovsky, K.; Baklanov, A.; Antonyuk, K.; Antonyuk, O.; Denisenko, D.
2011-06-01
We present time-resolved ground-based optical and space-based Swift UV and X-ray observations of the cataclysmic variable 1RXS J184542.4+483134 (USNO-B1.0 1385-0291789 18:45:42.622 +48:31:30.84, J2000; Monet et al. 2003 AJ, 125, 984) recently identified by Denisenko & Sokolovsky (2011 AstL, 37, 91) and Denisenko & Smirnov (2011 PZP, 11, 10). Photometry with the 2.6-m Shajn and 1.25-m AZT-11 telescopes of the Crimean astrophysical observatory was conducted on 2011 April 30, May 02, 03 and April 25, 26, respectively, for the total duration of about 14.6 hrs.
XMM-Newton discovery of pulsations from IGR J21237+4218=V2069 Cyg
NASA Astrophysics Data System (ADS)
de Martino, D.; Bonnet-Bidaud, J. M.; Falanga, M.; Mouchet, M.; Motch, C.
2009-06-01
We report on a preliminary analysis of a XMM-Newton observation of the INTEGRAL source IGR J21237+4218 identified as the cataclysmic variable RXJ2123.7+4217=V2069 Cyg (Motch et al. 1996 A&A 307, 459; Barlow et al. 2006, MNRAS 372, 224). This observation was performed on April 30, 2009 (Start time: 2009-04-30T10:45:58.000) for a total of 28ksec (Observation ID: 0601270101). The source is detected in the EPIC cameras at an average net countrate of 1.05 cts/sec (EPIC-pn) and 0.65cts/sec (EPIC-MOS).
How to Model Super-Soft X-ray Sources?
NASA Astrophysics Data System (ADS)
Rauch, Thomas
2012-07-01
During outbursts, the surface temperatures of white dwarfs in cataclysmic variables exceed by far half a million Kelvin. In this phase, they may become the brightest super-soft sources (SSS) in the sky. Time-series of high-resolution, high S/N X-ray spectra taken during rise, maximum, and decline of their X-ray luminosity provide insights into the processes following such outbursts as well as in the surface composition of the white dwarf. Their analysis requires adequate NLTE model atmospheres. The Tuebingen Non-LTE Model-Atmosphere Package (TMAP) is a powerful tool for their calculation. We present the application of TMAP models to SSS spectra and discuss their validity.
Shafer, Paul R; Davis, Kevin C; Patel, Deesha; Rodes, Robert; Beistle, Diane
2016-02-17
In 2012, the US Centers for Disease Control and Prevention (CDC) launched Tips From Former Smokers (Tips), the first federally funded national tobacco education campaign. In 2013, a follow-up Tips campaign aired on national cable television networks, radio, and other channels, with supporting digital advertising to drive traffic to the Tips campaign website. The objective of this study was to use geographic and temporal variability in 2013 Tips campaign television media doses and ad tagging to evaluate changes in traffic to the campaign website in response to specific doses of campaign media. Linear regression models were used to estimate the dose-response relationship between weekly market-level television gross rating points (GRPs) and weekly Web traffic to the Tips campaign website. This relationship was measured using unique visitors, total visits, and page views as outcomes. Ad GRP effects were estimated separately for ads tagged with the Tips campaign website URL and 1-800-QUIT-NOW. In the average media market, an increase of 100 television GRPs per week for ads tagged with the Tips campaign website URL was associated with an increase of 650 unique visitors (P<.001), 769 total visits (P<.001), and 1255 total page views (P<.001) per week. The associations between GRPs for ads tagged with 1-800-QUIT-NOW and each Web traffic measure were also statistically significant (P<.001), but smaller in magnitude. Based on these findings, we estimate that the 16-week 2013 Tips television campaign generated approximately 660,000 unique visitors, 900,000 total visits, and 1,390,000 page views for the Tips campaign website. These findings can help campaign planners forecast the likely impact of targeted advertising efforts on consumers' use of campaign-specific websites.
The relationship between LH and thyroid volume in patients with PCOS
2012-01-01
Background Thyroid volume (TV) has been found to be associated with age, anthropometry, smoking, iodine status and hyperinsulinemia. Hyperinsulinemia is frequent finding in patients with PCOS and has associations with TV. However, the TV has been evaluated only a few studies in patients with PCOS. Therefore, the aim of this study was to evaluate the biochemical and hormonal variables in patients with PCOS comparing with the controls and their relationships between TV. Methods This was a case–control study conducted in a training and research hospital. The study population consisted of 47 reproductive-age PCOS women and 30 control subjects. We evaluated anthropometric, biochemical and hormonal parameters as well as thyroid volume in PCOS patients and controls. Insulin resistance was calculated using the homeostasis model assessment insulin resistance index (HOMA-IR). Results Mean age, BMI, thyroid stimulant hormone (TSH) levels and TV were similar between groups (p<0.05). The HOMA-IR and free T4 levels were higher in patients with PCOS. However, hyperinsulinemia and insulin resistance were not found to be associated with TV. Thyroid volume was positively correlated with the LH and anti TPO levels. The participants were divided into 2 groups according to HOMA-IR levels. The mean TV measurement was higher in group with higher HOMA-IR levels, but the difference was not significant in young age PCOS patients. Conclusion In early age PCOS patients it was observed that insulin resistance had no effect on TV. In this case, anti TPO and LH have dominant effect on TV. Chronic stimulation with LH and insulin may lead to increase in TV in later stages of the PCOS diseases. PMID:23231775
ERIC Educational Resources Information Center
Van Mierlo, Jan; Van den Bulck, Jan
2004-01-01
This study found significant relationships between first- and second-order cultivation measures and TV viewing, but found a relationship with video game play for only two variables in a sample of 322 Flemish 3rd and 6th year secondary school children. This suggests that the absence of a relationship with video game play is not the result of the…
Urban and Rural Differences in Sedentary Behavior among American and Canadian Youth
Carson, Valerie; Iannotti, Ronald J.; Pickett, William; Janssen, Ian
2011-01-01
We examined relationships between urban-rural status and three screen time behaviors (television, computer, video games), and the potential mediating effect of parent and peer support on these relationships. Findings are based on American (n=8563) and Canadian (n=8990) youth in grades 6–10 from the 2005/06 Health Behaviour in School-Aged Children Survey. Weekly hours of individual screen time behaviors were calculated. Urban-rural status was defined using the Beale coding system. Parent and peer support variables were derived from principal component analysis. In comparison to the referent group (non-metro adjacent), American youth in the most rural areas were more likely to be high television users and less likely to be high computer users. Conversely, Canadian youth in medium and large metropolitan areas were less likely to be high television users and more likely to be high computer users. Parent and peer support did not strongly mediate the relationships between urban-rural status and screen time. These findings suggest that interventions aiming to reduce screen time may be most effective if they consider residential location and the specific screen time behavior. PMID:21565545
Dong, Zhichao; Cheng, Haobo; Tam, Hon-Yuen
2015-02-10
The velocity-varying regime used in deterministic subaperture polishing employs a time-invariant tool influence function (TIF) to figure localized surface errors by varying the transverse velocities of polishing tools. Desired transverse velocities have to be truncated if they exceed the maximal velocity of computer numerical control (CNC) machines, which induces excessive material removal and reduces figuring efficiency (FE). A time-variant (TV) TIF regime is presented, in which a TIF serves as a variable to compensate for excessive material removal when the transverse velocities are truncated. Compared with other methods, the TV-TIF regime exhibits better performance in terms of convergence rate, FE, and versatility; its operability can also be strengthened by a TIF library. Comparative experiments were conducted on a magnetorheological finishing machine to validate the effectiveness of the TV-TIF regime. Without a TV-TIF, the tool made an unwished dent (depth of 76 nm) at the center because of the velocity truncation problem. Through compensation with a TV-TIF, the dent was completely removed by the second figuring process, and a TV-TIF improved the FE from 0.029 to 0.066 mm(3)/h.
Urban and rural differences in sedentary behavior among American and Canadian youth.
Carson, Valerie; Iannotti, Ronald J; Pickett, William; Janssen, Ian
2011-07-01
We examined relationships between urban-rural status and three screen time behaviors (television, computer, video games), and the potential mediating effect of parent and peer support on these relationships. Findings are based on American (n = 8563) and Canadian (n = 8990) youth in grades 6-10 from the 2005/06 Health Behavior in School-Aged Children Survey. Weekly hours of individual screen time behaviors were calculated. Urban-rural status was defined using the Beale coding system. Parent and peer support variables were derived from principal component analysis. In comparison to the referent group (non-metro adjacent), American youth in the most rural areas were more likely to be high television users and less likely to be high computer users. Conversely, Canadian youth in medium and large metropolitan areas were less likely to be high television users and more likely to be high computer users. Parent and peer support did not strongly mediate the relationships between urban-rural status and screen time. These findings suggest that interventions aiming to reduce screen time may be most effective if they consider residential location and the specific screen time behavior. Copyright © 2011 Elsevier Ltd. All rights reserved.
Schrempft, Stephanie; van Jaarsveld, Cornelia H M; Fisher, Abigail; Wardle, Jane
2015-01-01
The home environment is thought to play a key role in early weight trajectories, although direct evidence is limited. There is general agreement that multiple factors exert small individual effects on weight-related outcomes, so use of composite measures could demonstrate stronger effects. This study therefore examined whether composite measures reflecting the 'obesogenic' home environment are associated with diet, physical activity, TV viewing, and BMI in preschool children. Families from the Gemini cohort (n = 1096) completed a telephone interview (Home Environment Interview; HEI) when their children were 4 years old. Diet, physical activity, and TV viewing were reported at interview. Child height and weight measurements were taken by the parents (using standard scales and height charts) and reported at interview. Responses to the HEI were standardized and summed to create four composite scores representing the food (sum of 21 variables), activity (sum of 6 variables), media (sum of 5 variables), and overall (food composite/21 + activity composite/6 + media composite/5) home environments. These were categorized into 'obesogenic risk' tertiles. Children in 'higher-risk' food environments consumed less fruit (OR; 95% CI = 0.39; 0.27-0.57) and vegetables (0.47; 0.34-0.64), and more energy-dense snacks (3.48; 2.16-5.62) and sweetened drinks (3.49; 2.10-5.81) than children in 'lower-risk' food environments. Children in 'higher-risk' activity environments were less physically active (0.43; 0.32-0.59) than children in 'lower-risk' activity environments. Children in 'higher-risk' media environments watched more TV (3.51; 2.48-4.96) than children in 'lower-risk' media environments. Neither the individual nor the overall composite measures were associated with BMI. Composite measures of the obesogenic home environment were associated as expected with diet, physical activity, and TV viewing. Associations with BMI were not apparent at this age.
Allom, Vanessa; Jongenelis, Michelle; Slevin, Terry; Keightley, Stacey; Phillips, Fiona; Beasley, Sarah; Pettigrew, Simone
2018-01-01
Reflecting the increasing prevalence of online media, many mass media health campaigns are now delivered using both television (TV) and online media formats. The aim of this study was to evaluate a smoking cessation mass media campaign according to the cost-effectiveness of the various combinations of TV and online media formats to inform future media buying decisions. A quasi-experimental interrupted time series approach was employed. The campaign was delivered in seven 1-week bursts using TV, online video (OV), or online display (OD) (e.g., banner ads) formats in isolation and in various combinations over a 13-week period. Campaign bursts were separated by "off-weeks" in which no campaign materials were delivered. Assessed outcomes were the number of campaign response "events" recorded (campaign web page views, calls to a smoking cessation telephone service, and registrations for smoking cessation services). The cost-effectiveness of each individual and combined media format condition in terms of these outcome variables was calculated using attributed production and broadcasting costs. Overall, OD alone was found to be the most cost-effective means of achieving the nominated campaign outcomes, followed by a combination of OV and OD and a combination of TV and OV. The use of TV in isolation was the least cost-effective. The results of this evaluation indicate that online media constitute a promising means of enhancing the cost-effectiveness of smoking cessation campaigns. Future research assessing a broader range of outcomes, especially smoking cessation, is needed to provide a more comprehensive account of the cost-effectiveness of various campaign media.
Effectiveness of a Television Advertisement Campaign on Giving Cigarettes in a Chinese Population
Qin, Yu; Su, Jian; Xiang, Quanyong; Hu, Yihe; Xu, Guanqun; Ma, Jiuhua; Shi, Zumin
2014-01-01
Background Anti-tobacco television advertisement campaigns may convey messages on smoking-related health consequences and create norms against giving cigarettes. Methods Altogether, 156 and 112 slots of a television advertisement “Giving cigarettes is giving harm” were aired on Suzhou and Yizheng, respectively, over one month in 2010. Participants were recruited from 15 locations in Suzhou and 8 locations in Yizheng using a street intercept method. Overall 2306 residents aged 18–45 years completed questionnaires, including 1142 before the campaign and 1164 after, with respective response rates of 79.1% and 79.7%. Chi square tests were used to compare the difference between categorical variables. Results After the campaign, 36.0% of subjects recalled that they had seen the advertisement. Residents of Suzhou had a higher recall rate than those of Yizheng (47.6% vs. 20.6%, P < 0.001). The rate of not giving cigarettes dropped from 32.1% before the campaign to 28.5% after (P = 0.05). In the post-campaign evaluation, participants who reported seeing the advertisement were more likely not to give cigarettes in the future than those who reported not seeing the advertisement (38.7% vs. 27.5%, P < 0.001). Conclusions Our study showed that an anti-tobacco television advertisements helped change societal norms and improve health behavior. Continuous and adequate funding of anti-tobacco media campaigns targeted at different levels of the general population is needed, in conjunction with a comprehensive tobacco control effort. PMID:25196169
Effectiveness of a television advertisement campaign on giving cigarettes in a chinese population.
Qin, Yu; Su, Jian; Xiang, Quanyong; Hu, Yihe; Xu, Guanqun; Ma, Jiuhua; Shi, Zumin
2014-01-01
Anti-tobacco television advertisement campaigns may convey messages on smoking-related health consequences and create norms against giving cigarettes. Altogether, 156 and 112 slots of a television advertisement "Giving cigarettes is giving harm" were aired on Suzhou and Yizheng, respectively, over one month in 2010. Participants were recruited from 15 locations in Suzhou and 8 locations in Yizheng using a street intercept method. Overall 2306 residents aged 18-45 years completed questionnaires, including 1142 before the campaign and 1164 after, with respective response rates of 79.1% and 79.7%. Chi square tests were used to compare the difference between categorical variables. After the campaign, 36.0% of subjects recalled that they had seen the advertisement. Residents of Suzhou had a higher recall rate than those of Yizheng (47.6% vs. 20.6%, P < 0.001). The rate of not giving cigarettes dropped from 32.1% before the campaign to 28.5% after (P = 0.05). In the post-campaign evaluation, participants who reported seeing the advertisement were more likely not to give cigarettes in the future than those who reported not seeing the advertisement (38.7% vs. 27.5%, P < 0.001). Our study showed that an anti-tobacco television advertisements helped change societal norms and improve health behavior. Continuous and adequate funding of anti-tobacco media campaigns targeted at different levels of the general population is needed, in conjunction with a comprehensive tobacco control effort.
Yepes, Maryam; Maurer, Jürgen; Viswanathan, Barathi; Gedeon, Jude; Bovet, Pascal
2016-05-20
Public radio and television announcements have a long tradition in public health education. With the global rise of computer and mobile device ownership, short message service (SMS) and email-based health services (mHealth) are promising new tools for health promotion. Our objectives were to examine 1) self-reported exposure to programs related to noncommunicable diseases (NCDs) on national public television and radio during the 12 months preceding the survey (2013-2014), 2) current ownership of a mobile phone, smartphone, computer, or tablet, and use of the Internet, and 3) willingness of individuals to receive SMS or emails with information on health, with a focus on distribution of these variables across different demographic, socioeconomic status (SES), and NCD risk groups. We obtained data in a population survey of 1240 participants aged 25-64 years conducted in 2013-2014 in the Seychelles, a rapidly developing small island state in the African region. We administered a structured questionnaire and measured NCD risk factors. Univariate and multivariate analyses explored the relationships between outcomes and sociodemographic variables. Of 1240 participants, 1037 (83.62%) reported exposure to NCD-related programs on public television, while a lower proportion of 740 adults (59.67%), reported exposure via public radio (P<.001). Exposure to NCD-related programs on public television was associated with older age (P<.001) and female sex (P<.001), but not with SES, while exposure to NCD-related programs on public radio was associated with older age (P<.001) and lower SES (P<.001). A total of 1156 (93.22%) owned a mobile phone and ownership was positively associated with female sex (P<.001), younger age (P<.001), and higher SES (P<.001). Only 396 adults (31.93%) owned a smartphone and 244 adults (19.67%) used their smartphone to access the Internet. A total of 1048 adults (84.51%) reported willingness to receive health-related SMS, which was positively associated with female sex (P<.001), younger age (P<.001), and higher SES (P<.001). Controlling for SES, exposure to NCD-related programs on public television or radio and willingness to receive health-related SMS were not independently associated with a person's NCD risk. Broadcasting health programs through traditional mass media (national public radio and television) reached the majority of the population under study, including older adults and those in lower socioeconomic groups. With a high penetration of mobile phones and willingness to receive health-related SMS, mHealth presents an opportunity for health programs, especially when targeted SMS messages are intended for younger adults and those in higher socioeconomic groups. By contrast, due to reduced Internet access, email-based programs had a more limited reach for health promotion programs. These findings emphasize the different reach of interventions using SMS or email versus traditional mass media, according to demographic and socioeconomic categories, for health education programs in a developing country.
IPHAS J025827.88+635234.9 and IPHAS J051814.33+294113.0: Two probable eclipsing intermediate polars
NASA Astrophysics Data System (ADS)
Joshi, Arti; Pandey, Jeewan Chandra
2018-04-01
We present photometry in the R-band and linear polarimetry of two cataclysmic variables, namely IPHAS J025827.88 + 635234.9 and IPHAS J051814.33 + 294113.0. The data were obtained from 1-m class tele-scopes of the Aryabhatta Research Institute of Observational Sciences (ARIES; Nainital, India). In addition to the deep eclipse, strong short-period oscillations are also found. We derived a pulse period of (1203 ± 25) s for IPHAS J025827.88 + 635234.9 and (3277 ± 81) s for IPHAS J051814.33 + 294113.0. The presence of both orbital and spin modulations in these systems indicate that they belong to a class of intermediate polars. The full width at half depth of the eclipse is also found to be variable from epoch to epoch for IPHAS J025827.88 + 635234.9. The presence of a variable linear polarization of high value in these two sources indicates that these systems possess a strong magnetic field.
On the Accretion Rates of SW Sextantis Nova-like Variables
NASA Astrophysics Data System (ADS)
Ballouz, Ronald-Louis; Sion, Edward M.
2009-06-01
We present accretion rates for selected samples of nova-like variables having IUE archival spectra and distances uniformly determined using an infrared method by Knigge. A comparison with accretion rates derived independently with a multiparametric optimization modeling approach by Puebla et al. is carried out. The accretion rates of SW Sextantis nova-like systems are compared with the accretion rates of non-SW Sextantis systems in the Puebla et al. sample and in our sample, which was selected in the orbital period range of three to four and a half hours, with all systems having distances using the method of Knigge. Based upon the two independent modeling approaches, we find no significant difference between the accretion rates of SW Sextantis systems and non-SW Sextantis nova-like systems insofar as optically thick disk models are appropriate. We find little evidence to suggest that the SW Sex stars have higher accretion rates than other nova-like cataclysmic variables (CVs) above the period gap within the same range of orbital periods.
DISCOVERY OF A WOLF-RAYET STAR THROUGH DETECTION OF ITS PHOTOMETRIC VARIABILITY
DOE Office of Scientific and Technical Information (OSTI.GOV)
Littlefield, Colin; Garnavich, Peter; McClelland, Colin
We report the serendipitous discovery of a heavily reddened Wolf-Rayet star that we name WR 142b. While photometrically monitoring a cataclysmic variable, we detected weak variability in a nearby field star. Low-resolution spectroscopy revealed a strong emission line at 7100 A, suggesting an unusual object and prompting further study. A spectrum taken with the Hobby-Eberly Telescope confirms strong He II emission and an N IV 7112 A line consistent with a nitrogen-rich Wolf-Rayet star of spectral class WN6. Analysis of the He II line strengths reveals no detectable hydrogen in WR 142b. A blue-sensitive spectrum obtained with the Large Binocularmore » Telescope shows no evidence for a hot companion star. The continuum shape and emission line ratios imply a reddening of E(B - V) = 2.2-2.6 mag. We estimate that the distance to WR 142b is 1.4 {+-} 0.3 kpc.« less
MONET, HET and SALT and asteroseismological observations and theory in Göttingen
NASA Astrophysics Data System (ADS)
Schuh, S.; Hessman, F. V.; Dreizler, S.; Kollatschny, W.; Glatzel, W.
2007-06-01
The Göttingen stellar astrophysics group, headed by Stefan Dreizler, conducts research on extrasolar planets and their host stars, on lower-main sequence stars, and on evolved compact objects, in particular hot white dwarfs (including PG 1159 objects, magnetic WDs and cataclysmic variables), and subdwarf B stars. In addition to sophisticated NLTE spectral analyses of these stars, which draw on the extensive stellar atmosphere modelling experience of the group, we actively develop and apply a variety of photometric monitoring and time-resolved spectroscopic techniques to address time-dependent phenomena. With the new instrumentational developments described below, we plan to continue the study of variable white dwarfs (GW Vir, DB and ZZ Ceti variables) and in particular sdB EC 14026 and PG 1617 pulsators which already constitute a main focus, partly within the Whole Earth Telescope (WET/DARC), http://www.physics.udel.edu/~jlp/darc/) collaboration, on a new level. Additional interest is directed towards strange mode instabilities in Wolf Rayet stars.
Models for Predicting the Biomass of Cunninghamialanceolata Trees and Stands in Southeastern China
Saeed, Sajjad
2017-01-01
Using existing equations to estimate the biomass of a single tree or a forest stand still involves large uncertainties. In this study, we developed individual-tree biomass models for Chinese Fir (Cunninghamia lanceolata.) stands in Fujian Province, southeast China, by using 74 previously established models that have been most commonly used to estimate tree biomass. We selected the best fit models and modified them. The results showed that the published model ln(B(Biomass)) = a + b * ln(D) + c * (ln(H))2 + d * (ln(H))3 + e * ln(WD) had the best fit for estimating the tree biomass of Chinese Fir stands. Furthermore, we observed that variables D(diameter at breast height), H (height), and WD(wood density)were significantly correlated with the total tree biomass estimation model. As a result, a natural logarithm structure gave the best estimates for the tree biomass structure. Finally, when a multi-step improvement on tree biomass model was performed, the tree biomass model with Tree volume(TV), WD and biomass wood density conversion factor (BECF),achieved the highest simulation accuracy, expressed as ln(TB) = −0.0703 + 0.9780 * ln(TV) + 0.0213 * ln(WD) + 1.0166 * ln(BECF). Therefore, when TV, WD and BECF were combined with tree biomass volume coefficient bi for Chinese Fir, the stand biomass (SB)model included both volume(SV) and coefficient bi variables of the stand as follows: bi = Exp(−0.0703+0.9780*ln(TV)+0.0213 * ln(WD)+1.0166*ln(BECF)). The stand biomass model is SB = SV/TV * bi. PMID:28095512
Models for Predicting the Biomass of Cunninghamialanceolata Trees and Stands in Southeastern China.
Guangyi, Mei; Yujun, Sun; Saeed, Sajjad
2017-01-01
Using existing equations to estimate the biomass of a single tree or a forest stand still involves large uncertainties. In this study, we developed individual-tree biomass models for Chinese Fir (Cunninghamia lanceolata.) stands in Fujian Province, southeast China, by using 74 previously established models that have been most commonly used to estimate tree biomass. We selected the best fit models and modified them. The results showed that the published model ln(B(Biomass)) = a + b * ln(D) + c * (ln(H))2 + d * (ln(H))3 + e * ln(WD) had the best fit for estimating the tree biomass of Chinese Fir stands. Furthermore, we observed that variables D(diameter at breast height), H (height), and WD(wood density)were significantly correlated with the total tree biomass estimation model. As a result, a natural logarithm structure gave the best estimates for the tree biomass structure. Finally, when a multi-step improvement on tree biomass model was performed, the tree biomass model with Tree volume(TV), WD and biomass wood density conversion factor (BECF),achieved the highest simulation accuracy, expressed as ln(TB) = -0.0703 + 0.9780 * ln(TV) + 0.0213 * ln(WD) + 1.0166 * ln(BECF). Therefore, when TV, WD and BECF were combined with tree biomass volume coefficient bi for Chinese Fir, the stand biomass (SB)model included both volume(SV) and coefficient bi variables of the stand as follows: bi = Exp(-0.0703+0.9780*ln(TV)+0.0213 * ln(WD)+1.0166*ln(BECF)). The stand biomass model is SB = SV/TV * bi.
Physical activity, stress, and metabolic risk score in 8- to 18-year-old boys.
Holmes, Megan E; Eisenmann, Joey C; Ekkekakis, Panteleimon; Gentile, Douglas
2008-03-01
We examined whether physical activity modifies the relationship between stress and the metabolic risk score in 8- to 18-year-old males (n = 37). Physical activity (PA) and television (TV)/videogame (VG) use were assessed via accelerometer and questionnaire, respectively. Stress was determined from self-report measures. A metabolic risk score (MRS) was created by summing age-standardized residuals for waist circumference, mean arterial pressure, glycosylated hemoglobin, and high-density lipoprotein cholesterol. Correlations between PA and MRS were low (r < -.13), and TV and VG were moderately associated with MRS (r = .39 and .43, respectively). Correlations between stress-related variables and MRS ranged from r = .19 to .64. After partitioning by PA, significant correlations were observed in the low PA group between school- and sports-related self-esteem and anxiety with the MRS. The results provide suggestive evidence that PA might modify the relationship between stress and MRS in male adolescents.
Television experiment for Mariner Mars 1971
Masursky, H.; Batson, R.; Borgeson, W.; Carr, M.; McCauley, J.; Milton, D.; Wildey, R.; Wilhelms, D.; Murray, B.; Horowitz, N.; Leighton, R.; Sharp, R.; Thompson, W.; Briggs, G.; Chandeysson, P.; Shipley, E.; Sagan, C.; Pollack, J.; Lederberg, J.; Levinthal, E.; Hartmann, W.; McCord, T.; Smith, B.; Davies, M.; De Vaucouleurs, G.; Leovy, C.
1970-01-01
The Television Experiment objectives are to provide imaging data which will complement previously gathered data and extend our knowledge of Mars. The two types of investigations will be fixed-feature (for mapping) and variable-feature (for surface and atmospheric changes). Two cameras with a factor-of-ten difference in resolution will be used on each spacecraft for medium- and high-resolution imagery. Mapping of 70% of the planet's surface will be provided by medium-resolution imagery. Spot coverage of about 5% of the surface will be possible with the high-resolution imagery. The experiment's 5 Principal Investigators and 21 Co-Investigators are organized into a team. Scientific disciplines and technical task groups have been formed to provide the formulation of experiment requirements for mission planning and instrument development. It is expected that the team concept will continue through the operational and reporting phases of the Mariner Mars 1971 Project. ?? 1970.
Solid state electro-optic color filter and iris
NASA Technical Reports Server (NTRS)
1974-01-01
The electro-optic properties of lanthanum-modified lead zirconate titanate (PLZT) ferroelectric ceramic material are evaluated when utilized as a variable density and/or spectral filter in conjunction with a television scanning system. Emphasis was placed on the development of techniques and procedures for processing the PLZT disks and for applying efficient electrode structures. A number of samples were processed using different combinations of cleaning, electrode material, and deposition process. Best overall performance resulted from the direct evaporation of gold over chrome electrodes. A ruggedized mounting holder assembly was designed, fabricated, and tested. The assembly provides electrical contacts, high voltage protection, and support for the fragile PLZT disk, and permits mounting and optical alignment of the associated polarizers. Operational measurements of a PLZT sample mounted in the holder assembly were performed in conjunction with a television camera and the associated drive circuits. The data verified achievement of the elimination of the observed white-line effect.
The Onset of the Cataclysm: In Situ Dating of the Nectaris Basin Impact Melt Sheet
NASA Technical Reports Server (NTRS)
Cohen, B. A.
2017-01-01
The impact history of the Moon has significant implications beyond simply excavating the surface of our nearest neighbor. The age distribution of lunar impact breccias inspired the idea of a catastrophic influx of asteroids and comets about 4 billion years ago and motivated new models of planetary dynamics. An epoch of heavy bombardment after planets had atmospheres and continents would have influenced the course of biologic evolution. The story of a cataclysmic bombardment, written in the rocks of the Moon, has far-reaching consequences.
The Effect of Interactive Simulations on Exercise Adherence with Overweight and Obese Adults
2011-03-01
bicycle: one while watching television and the other one while playing video games . Related variables tested were exercise motivation and self-efficacy in...overweight and obese adults. Unique software was written to integrate the exercise equipment/ video game components, and to capture and transfer...Start Letter was received on Dec 20, 2010 and recruitment of participants commenced in Feb 2011. Prototype exercise bicycle with video gaming console
Alborzi, Saeed; Rasekhi, Alireza; Shomali, Zahra; Madadi, Gooya; Alborzi, Mahshid; Kazemi, Mahboobeh; Hosseini Nohandani, Azam
2018-01-01
Abstract To determine the diagnostic accuracy of pelvic magnetic resonance imaging (MRI), transvaginal sonography (TVS), and transrectal sonography (TRS) in diagnosis of deep infiltrating endometriosis (DIE). This diagnostic accuracy study was conducted during a 2-year period including a total number of 317 patients with signs and symptoms of endometriosis. All the patients were evaluated by pelvic MRI, TVS, and TRS in the same center. The criterion standard was considered to be the laparoscopy and histopathologic examination. Of 317 patients being included in the present study, 252 tested positive for DIE. The sensitivity, specificity, positive predictive value, and negative predictive value of TVS was found to be 83.3%, 46.1%, 85.7%, and 41.6%, respectively. These variables were 80.5%, 18.6%, 79.3%, and 19.7% for TRS and 90.4%, 66.1%, 91.2%, and 64.1% for MRI, respectively. MRI had the highest accuracy (85.4%) when compared to TVS (75.7%) and TRS (67.8%). The sensitivity of TRS, TVS, and MRI in uterosacral ligament DIE was 82.8%, 70.9%, and 63.6%, respectively. On the contrary, specificity had a reverse trend, favoring MRI (93.9%, 92.8%, and 89.8% for TVS and TRS, respectively). The results of the present study demonstrated that TVS and TRS have appropriate diagnostic accuracy in diagnosis of DIE comparable to MRI. PMID:29465552
Chang, Feng-Hsun; Lawrence, Justin E; Rios-Touma, Blanca; Resh, Vincent H
2014-04-01
Tolerance values (TVs) based on benthic macroinvertebrates are one of the most widely used tools for monitoring the biological impacts of water pollution, particularly in streams and rivers. We compiled TVs of benthic macroinvertebrates from 29 regions around the world to test 11 basic assumptions about pollution tolerance, that: (1) Arthropoda are < tolerant than non-Arthropoda; (2) Insecta < non-Insecta; (3) non-Oligochaeta < Oligochaeta; (4) other macroinvertebrates < Oligochaeta + Chironomidae; (5) other macroinvertebrate taxa < Isopoda + Gastropoda + Hirudinea; (6) Ephemeroptera + Plecoptera + Trichoptera (EPT) < Odonata + Coleoptera + Heteroptera (OCH); (7) EPT < non-EPT insects; (8) Diptera < Insecta; (9) Bivalvia < Gastropoda; (10) Baetidae < other Ephemeroptera; and (11) Hydropsychidae < other Trichoptera. We found that the first eight of these 11 assumptions were supported despite regional variability. In addition, we examined the effect of Best Professional Judgment (BPJ) and non-independence of TVs among countries by performing all analyses using subsets of the original dataset. These subsets included a group based on those systems using TVs that were derived from techniques other than BPJ, and groups based on methods used for TV assignment. The results obtained from these subsets and the entire dataset are similar. We also made seven a priori hypotheses about the regional similarity of TVs based on geography. Only one of these was supported. Development of TVs and the reporting of how they are assigned need to be more rigorous and be better described.
Rousseau, Ann; Gamble, Hilary; Eggermont, Steven
2017-10-01
Individuals who are more strongly invested in their appearance, appearance schematics, have a tendency to engage in appearance-related comparison. Appearance schematicity consists of two components. The self-evaluative component concerns the degree to which appearance is central to self-worth, referred to as dysfunctional appearance beliefs. Motivational salience refers to the engagement in behaviors designed to enhance appearance, such as body surveillance. Based on a three-wave panel survey of 973 Flemish preadolescents (M age = 11.15, SD = 1.13) we found that the motivational and self-evaluative components had a different impact on media internalization. For preadolescents who engaged in more body surveillance, watching television resulted in more media internalization. For preadolescents who had fewer dysfunctional appearance beliefs, watching television resulted in more media internalization. These findings suggest that appearance schematicity is an important susceptibility variable in the relationship between TV-exposure and media internalization, and emphasize the importance of investigating individual dispositions beyond gender differences. Copyright © 2017 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.
Correlates of adiposity among Latino preschool children.
Mendoza, Jason A; McLeod, Jessica; Chen, Tzu-An; Nicklas, Theresa A; Baranowski, Tom
2014-01-01
Childhood obesity is at record high levels in the US and disproportionately affects Latino children; however, studies examining Latino preschool children's obesity-related risk factors are sparse. This study determined correlates of Latino preschoolers' (ages 3-5 years) adiposity to inform future obesity interventions and policies. Latino preschoolers (n = 96) from 4 Head Start centers in Houston, Texas were recruited. Parents reported acculturation and neighborhood safety. Children's and parents' height and weight were measured. Children's television (TV) viewing was measured by TV diaries and physical activity by accelerometers. Linear regression was used with body mass index (BMI) z-score as the dependent variable and covariates sequentially added and retained in 4 blocks: 1) child age, gender, parent education, and BMI; 2) neighborhood safety and parent and child acculturation; 3) TV viewing; and 4) moderate-to-vigorous physical activity (MVPA). In the final model (n = 96), only neighborhood disorder (β = 0.30, P = .005) and MVPA (β = -0.21, P = .049) were significantly associated with BMI z-score. Among Latino preschoolers, higher neighborhood disorder and lower MVPA were associated with greater children's BMI z-scores.
NASA Astrophysics Data System (ADS)
Bai, Bing
2012-03-01
There has been a lot of work on total variation (TV) regularized tomographic image reconstruction recently. Many of them use gradient-based optimization algorithms with a differentiable approximation of the TV functional. In this paper we apply TV regularization in Positron Emission Tomography (PET) image reconstruction. We reconstruct the PET image in a Bayesian framework, using Poisson noise model and TV prior functional. The original optimization problem is transformed to an equivalent problem with inequality constraints by adding auxiliary variables. Then we use an interior point method with logarithmic barrier functions to solve the constrained optimization problem. In this method, a series of points approaching the solution from inside the feasible region are found by solving a sequence of subproblems characterized by an increasing positive parameter. We use preconditioned conjugate gradient (PCG) algorithm to solve the subproblems directly. The nonnegativity constraint is enforced by bend line search. The exact expression of the TV functional is used in our calculations. Simulation results show that the algorithm converges fast and the convergence is insensitive to the values of the regularization and reconstruction parameters.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Szkody, Paula; Mukadam, Anjum S.; Toloza, Odette
2017-03-01
Time-tag ultraviolet data obtained on the Hubble Space Telescope in 2013 reveal interesting variability related to the white dwarf spin in the two cataclysmic variables RZ Leo and CC Scl. RZ Leo shows a period at 220 s and its harmonic at 110 s, thus identifying it as a likely Intermediate Polar (IP). The spin signal is not visible in a short single night of ground-based data in 2016, but the shorter exposures in that data set indicate a possible partial eclipse. The much larger UV amplitude of the spin signal in the known IP CC Scl allows the spinmore » of 389 s, previously only seen at outburst, to be visible at quiescence. Spectra created from the peaks and troughs of the spin times indicate a hotter temperature of several thousand degrees during the peak phases, with multiple components contributing to the UV light.« less
On the origin of the peculiar cataclysmic variable AE Aquarii
NASA Astrophysics Data System (ADS)
Beskrovnaya, N. G.; Ikhsanov, N. R.
2015-02-01
The nova-like variable AE Aquarii is a close binary system containing a red dwarf and a magnetized white dwarf rotating with the period of 33 s. A short spin period of the white dwarf is caused by an intensive mass exchange between the system components during a previous epoch. We show that a high rate of disk accretion onto the white dwarf surface resulted in temporary screening of its magnetic field and spin-up of the white dwarf to its present spin period. Transition of the white dwarf to the ejector state occurred at a final stage of the spin-up epoch after its magnetic field had emerged from the accreted plasma due to diffusion. In the frame of this scenario AE Aqr represents a missing link in the chain of Polars evolution and the white dwarf resembles a recycled pulsar.
Clark, Levina; Tiggemann, Marika
2008-07-01
This study investigated the prospective predictors of body image in 9- to 12-year-old girls. Participants were 150 girls in Grades 4-6 with a mean age of 10.3 years. Girls completed questionnaire measures of media and peer influences (television/magazine exposure, peer appearance conversations), individual psychological variables (appearance schemas, internalization of appearance ideals, autonomy), and body image (figure discrepancy and body esteem) at Time 1 and 1 year later at Time 2. Linear panel analyses showed that after controlling for Time 1 levels of body image, none of the Time 1 sociocultural variables predicted body image variables at Time 2. Body mass index (BMI; a biological variable) and psychological variables, however, did offer significant prospective prediction. Specifically, higher BMI, higher appearance schemas, higher internalization of appearance ideals, and lower autonomy predicted worsening body image 1 year later. Thus, higher weight and certain psychological characteristics were temporally antecedent to body image concerns. It was concluded that both biological and individual psychological variables play a role in the development of body image in children. Individual psychological variables, in particular, may provide useful targets in prevention and intervention programs addressing body image in 9- to 12-year-old girls.
Al Sabbah, H; Vereecken, C; Abdeen, Z; Coats, E; Maes, L
2009-02-01
Overweight and obesity as well as weight dissatisfaction have been increasing in prevalence worldwide. Body weight dissatisfaction and fear of fatness are potential contributors to disordered eating. The present study aimed to investigate the prevalence of self-reported overweight and weight dissatisfaction along with associations with socio-demographic characteristics, body image, health complaints, risk behaviours, physical activity and television viewing in adolescents in Palestine. The 2003/04 Palestinian Health Behaviour in School-aged Children (HBSC) is a cross-sectional survey of 17,817 adolescents from 405 randomly selected schools. Students from a representative sample of grades 6, 8, 10 and 12 (aged 12-18 years) self-completed a modified version of the international World Health Organization collaborative Health Behaviour in School-aged Children (HBSC-2002) questionnaire. Although 16.5% of the adolescents were overweight, almost twice that number (32.1%) were dissatisfied with their weight (i.e. dieting or perceiving a need to diet). Of those adolescents, two-thirds were not actually overweight (56.4% boys; 73.5% girls). One-fifth of the total number of adolescents (16.0% boys; 24.0% girls) were not overweight but were dissatisfied with their weight. Boys reporting overweight or weight dissatisfaction were more likely to have mothers with higher education or to be from more affluent families. Among both genders, but especially among girls, weight dissatisfaction was positively associated with most of the outcome variables (body image, health complaints, risk behaviours, and television viewing) regardless of weight status, whereas weight status was associated with only a few of the outcome variables. Weight dissatisfaction, independent of weight status, is associated with body image, health complaints, risk behaviours and television viewing, and represents a potential health risk factor for adolescents. Preventive interventions should focus not only on weight status, but also on body weight dissatisfaction.
TV Viewing and BMI by Race/Ethnicity and Socio-Economic Status
Shuval, Kerem; Gabriel, Kelley Pettee; Leonard, Tammy
2013-01-01
Objective To assess the association between TV viewing and obesity by race/ethnicity and socio-economic status. Design Cross-sectional analysis of 5,087 respondents to the Health Information National Trends Survey (HINTS), a nationally representative sample of US adults. Multivariate regression models were computed to assess the association between quartiles of TV viewing and BMI, stratified by race/ethnicity, educational attainment, employment and health insurance status. Results Findings indicate that increased TV viewing was associated with higher odds for being overweight/obese in the entire sample, while adjusting for physical activity and other confounders. After stratification by race/ethnicity, increased odds for overweight/obesity in the 3rd and 4th quartiles of TV viewing (e.g., 3rd quartile- cumulative OR = 1.43, 95%CI 1.07–1.92) was observed in non-Hispanic whites, with statistical significance. In non-Hispanic blacks and Hispanics, the odds were similar to whites, but did not reach statistical significance. Significant relations between greater TV viewing and increased BMI were observed in college graduates and non-graduates, those with health insurance and the employed. Conclusions This study extends previous research by examining potential inconsistencies in this association between various racial/ethnic groups and some socio-economic variables, which primarily were not found. PMID:23691070
Kuntsche, Emmanuel N
2004-03-01
To determine what kind of violence-related behavior or opinion is directly related to excessive media use among adolescents in Switzerland. A national representative sample of 4222 schoolchildren (7th- and 8th-graders; mean age 13.9 years) answered questions on the frequency of television-viewing, electronic game-playing, feeling unsafe at school, bullying others, hitting others, and fighting with others, as part of the Health Behaviour in School-Aged Children (HBSC) international collaborative study protocol. The Chi-square tests and multiple logistic regression analyses were applied to high-risk groups of adolescents. For the total sample, all bivariate relationships between television-viewing/electronic game-playing and each violence-related variable are significant. In the multivariate comparison, physical violence among boys ceases to be significant. For girls, only television-viewing is linked to indirect violence. Against the hypothesis, females' electronic game-playing only had a bearing on hitting others. Experimental designs are needed that take into account gender, different forms of media, and violence to answer the question of whether excessive media use leads to violent behavior. With the exception of excessive electronic game-playing among girls, this study found that electronic media are not thought to lead directly to real-life violence but to hostility and indirect violence.
Portrayals of Reproductive and Sexual Health on Primetime Television
Pariera, Katrina L.; Hether, Heather J.; Murphy, Sheila T.; de Castro Buffington, Sandra; Baezconde-Garbanati, Lourdes
2013-01-01
Primetime broadcast television provides health information and establishes norms for millions of people in the United States (Beck, 2004; Brodie, et al., 2001; Murphy & Cody, 2003; Rideout, 2008). To understand what people may be learning about reproductive and sexual health, a content analysis was conducted of storylines from the 10 most popular primetime television programs in 2009, 2010 and 2011. Variables that were measured included the frequency of reproductive and sexual health issues, the level of health information, the type of information portrayed, the gain and loss frames, the presence of stigma, the tone, and the type of role model portrayed. Eighty-seven of the 589 health storylines dealt with reproductive and sexual health, and the most common issues were pre- and post-term pregnancy complications. The majority of these storylines had a moderate or weak level of information and included specifics about treatment and symptoms but not prevention. Just over half of the issues were framed in terms of losses, meaning non-adoption of a behavior change will result in negative outcomes. Twenty-four percent of reproductive and sexual health storylines involved stigma -- usually those related to sexually transmitted infections (STIs). Most storylines were portrayed as serious and the majority of issues happened to positive role models. The implications of these portrayals for the viewing public are discussed. PMID:24156468
Media violence exposure and physical aggression in fifth-grade children.
Coker, Tumaini R; Elliott, Marc N; Schwebel, David C; Windle, Michael; Toomey, Sara L; Tortolero, Susan R; Hertz, Marci F; Peskin, Melissa F; Schuster, Mark A
2015-01-01
To examine the association of media violence exposure and physical aggression in fifth graders across 3 media types. We analyzed data from a population-based, cross-sectional survey of 5,147 fifth graders and their parents in 3 US metropolitan areas. We used multivariable linear regression and report partial correlation coefficients to examine associations between children's exposure to violence in television/film, video games, and music (reported time spent consuming media and reported frequency of violent content: physical fighting, hurting, shooting, or killing) and the Problem Behavior Frequency Scale. Child-reported media violence exposure was associated with physical aggression after multivariable adjustment for sociodemographics, family and community violence, and child mental health symptoms (partial correlation coefficients: TV, 0.17; video games, 0.15; music, 0.14). This association was significant and independent for television, video games, and music violence exposure in a model including all 3 media types (partial correlation coefficients: TV, 0.11; video games, 0.09; music, 0.09). There was a significant positive interaction between media time and media violence for video games and music but not for television. Effect sizes for the association of media violence exposure and physical aggression were greater in magnitude than for most of the other examined variables. The association between physical aggression and media violence exposure is robust and persistent; the strength of this association of media violence may be at least as important as that of other factors with physical aggression in children, such as neighborhood violence, home violence, child mental health, and male gender. Copyright © 2015 Academic Pediatric Association. All rights reserved.
Associations between television viewing and love styles: an interpretation using cultivation theory.
Hetsroni, Amir
2012-02-01
This study evaluated the associations between television viewing and love styles. The Love Attitudes Scale (LAS), based on Lee's love style taxonomy, was administered to a sample of 338 unmarried Israeli students along with questions about TV viewing habits, current involvement in a serious romantic relationship, and marital intentions. A confirmatory factor analysis of the LAS indicated that the expected six-factor solution adequately fit the data. Correlations between individual love styles and TV viewing were small to moderate, ranging from .12 to .29. Scores for Ludus love style correlated positively with viewing of news and general programming. Those for Pragma love style correlated positively with news viewing and negatively with viewing genres frequently including love themes such as soap operas and family drama, while scores for Eros love style positively correlated with watching these love abundant genres. No significant association was found for TV viewing with Storge, Mania, and Agape love styles. Hierarchical regression using demographic variables, love status, and viewing habits mirrored these results, with the unique R2 for Ludus, Pragma, and Eros ranging from 1.8% to 8%, while the total variance accounted for by the models ranged from 12% to 21%. The findings can be interpreted as support for a weak cultivation effect, in which habits in long-term TV viewing among young adults correspond to small to moderate tendencies for particular love styles that thematically relate them. However, because they are correlational, the findings could equally be interpreted in terms of tendencies that exist due to modeling within families and socialization during development.
A Content Analysis of Television Ads: Does Current Practice Maximize Cognitive Processing?
2008-12-11
ads with arousing content such as sexual imagery and fatty/sweet food imagery have the potential to stress the cognitive processing system. When the...to examine differences in content arousal , this study included variables shown to elicit arousal —loved brands, sexual images, and fatty/sweet food...loved brands as well as ads with sexual and fatty/food images are not all the same—they are not likely to be equally arousing . Initially, brands were
Neighbourhood Influences on Children's Weight-related Behaviours and Body Mass Index.
Jenkin, Gabrielle L; Pearson, Amber L; Bentham, Graham; Day, Peter; Kingham, Simon
2015-01-01
Neighbourhood contextual factors such as accessibility of food shops and green spaces are associated with adult bodyweight but not necessarily weight-related behaviours. Whether these associations are replicated amongst children is unknown. To understand which aspects of childrens' neighbourhoods are associated with unhealthy weight and weight-related behaviours. Individual-level data for children from the 2006/7 New Zealand Health Survey (of Body Mass Index (BMI), dietary indicators and socioeconomic variables) were linked with geographic level data on neighbourhood deprivation, rural/urban status, percentage of community engaged in active travel, access to green space, food shops and sports/leisure facilities. Logistic regression models were fitted for measures of BMI and weight-related behaviours; sugar sweetened beverage (SSB) consumption; fast-food consumption; and television viewing. Increased community engagement in active transport was, counterintuitively, the only neighbourhood contextual factor associated with unhealthy weight amongst children. After adjustment for socioeconomic and environmental variables, greater access to green space appeared to have a protective effect on SSB consumption and neighbourhood deprivation was associated with all three unhealthy weight-related behaviours (SSB and fast-food consumption and television viewing). Although further research is needed, evidence from the current study suggests that a repertoire of health promotion interventions and policies to change unhealthy weight-related behaviours in high deprivation neighbourhoods may be required to address childhood obesity.
The Impact History Of The Moon
NASA Technical Reports Server (NTRS)
Cohen, B. A.
2010-01-01
The bombardment history of the Earth-Moon system has been debated since the first recognition that the circular features on the Moon may be impact craters. Because the lunar impact record is the only planetary impact record to be calibrated with absolute ages, it underpins our understanding of geologic ages on every other terrestrial planet. One of the more remarkable results to come out of lunar sample analyses is the hypothesis that a large number of impact events occurred on the Moon during a narrow window in time approximately 3.8 to 4.1 billion years ago (the lunar cataclysm ). Subsequent work on the lunar and martian meteorite suites; remote sensing of the Moon, Mars, asteroids, and icy satellites; improved dynamical modeling; and investigation of terrestrial zircons extend the cataclysm hypothesis to the Earth, other terrestrial planets, and possibly the entire solar system. Renewed US and international interest in exploring the Moon offers new potential to constrain the Earth-Moon bombardment history. This paper will review the lunar bombardment record, timing and mechanisms for cataclysmic bombardment, and questions that may be answered in a new age of exploration.
Real-time demonstration hardware for enhanced DPCM video compression algorithm
NASA Technical Reports Server (NTRS)
Bizon, Thomas P.; Whyte, Wayne A., Jr.; Marcopoli, Vincent R.
1992-01-01
The lack of available wideband digital links as well as the complexity of implementation of bandwidth efficient digital video CODECs (encoder/decoder) has worked to keep the cost of digital television transmission too high to compete with analog methods. Terrestrial and satellite video service providers, however, are now recognizing the potential gains that digital video compression offers and are proposing to incorporate compression systems to increase the number of available program channels. NASA is similarly recognizing the benefits of and trend toward digital video compression techniques for transmission of high quality video from space and therefore, has developed a digital television bandwidth compression algorithm to process standard National Television Systems Committee (NTSC) composite color television signals. The algorithm is based on differential pulse code modulation (DPCM), but additionally utilizes a non-adaptive predictor, non-uniform quantizer and multilevel Huffman coder to reduce the data rate substantially below that achievable with straight DPCM. The non-adaptive predictor and multilevel Huffman coder combine to set this technique apart from other DPCM encoding algorithms. All processing is done on a intra-field basis to prevent motion degradation and minimize hardware complexity. Computer simulations have shown the algorithm will produce broadcast quality reconstructed video at an average transmission rate of 1.8 bits/pixel. Hardware implementation of the DPCM circuit, non-adaptive predictor and non-uniform quantizer has been completed, providing realtime demonstration of the image quality at full video rates. Video sampling/reconstruction circuits have also been constructed to accomplish the analog video processing necessary for the real-time demonstration. Performance results for the completed hardware compare favorably with simulation results. Hardware implementation of the multilevel Huffman encoder/decoder is currently under development along with implementation of a buffer control algorithm to accommodate the variable data rate output of the multilevel Huffman encoder. A video CODEC of this type could be used to compress NTSC color television signals where high quality reconstruction is desirable (e.g., Space Station video transmission, transmission direct-to-the-home via direct broadcast satellite systems or cable television distribution to system headends and direct-to-the-home).
Edwards, Jane U; Mauch, Lois; Winkelman, Mark R
2011-02-01
To support curriculum and policy, a midwest city school district assessed the association of selected categories of nutrition and physical activity (NUTR/PA) behaviors, fitness measures, and body mass index (BMI) with academic performance (AP) for 800 sixth graders. Students completed an adapted Youth Risk Behavior Surveillance Survey (NUTR/PA behaviors), fitness assessments (mile run, curl-ups, push-ups, height, and weight) with results matched to standardized scores (Measures of Academic Progress [MAP]), meal price status, and gender. Differences in mean MAP scores (math and reading) were compared by selected categories of each variable utilizing 1-way analysis of variance. Associations were determined by stepwise multiple regression utilizing mean MAP scores (for math and for reading) as the dependent variable and NUTR/PA behaviors, fitness, and BMI categories as independent variables. Significance was set at α = 0.05. Higher MAP math scores were associated with NUTR (more milk and breakfast; less 100% fruit juice and sweetened beverages [SB]) and PA (increased vigorous PA and sports teams; reduced television), and fitness (higher mile run performance). Higher MAP reading scores were associated with NUTR (fewer SB) and PA (increased vigorous PA, reduced television). Regression analysis indicated about 11.1% of the variation in the mean MAP math scores and 6.7% of the mean MAP reading scores could be accounted for by selected NUTR/PA behaviors, fitness, meal price status, and gender. Many positive NUTR/PA behaviors and fitness measures were associated with higher MAP scores supporting the school district focus on healthy lifestyles. Additional factors, including meal price status and gender, contribute to AP. © 2011, Fargo Public School.
Morais, Jorge E; Silva, António J; Garrido, Nuno D; Marinho, Daniel A; Barbosa, Tiago M
2018-03-24
The purpose of this study was to learn the interplay between dry-land strength and conditioning, and stroke biomechanics in young swimmers, during a 34-week training programme. Twenty-seven swimmers (overall: 13.33 ± 0.85 years old; 11 boys: 13.5 ± 0.75 years old; 16 girls: 13.2 ± 0.92 years old) competing at regional- and national-level competitions were evaluated. The swimmers were submitted to a specific in-water and dry-land strength training over 34 weeks (and evaluated at three time points: pre-, mid-, and post-test; M1, M2, and M3, respectively). The 100-m freestyle performance was chosen as the main outcome (i.e. dependent variable). The arm span (AS; anthropometrics), throwing velocity (TV; strength), stroke length (SL), and stroke frequency (SF; kinematics) were selected as independent variables. There was a performance enhancement over time (M1 vs. M3: 68.72 ± 5.57 s, 66.23 ± 5.23 s; Δ = -3.77%; 95% CI: -3.98;-3.56) and an overall improvement of the remaining variables. At M1 and M2, all links between variables presented significant effects (p < .001), except the TV-SL and the TV-SF path. At M3, all links between variables presented significant effects (p ≤ .05). Between M1 and M3, the direct effect of the TV to the stroke biomechanics parameters (SL and SF) increased. The model predicted 89%, 88%, and 92% of the performance at M1, M2, and M3, respectively, with a reasonable adjustment (i.e. goodness-of-fit M1: χ 2 /df = 3.82; M2: χ 2 /df = 3.08; M3: χ 2 /df = 4.94). These findings show that strength and conditioning parameters have a direct effect on the stroke biomechanics, and the latter one on the swimming performance.
Study of shock waves and related phenomena motivated by astrophysics
DOE Office of Scientific and Technical Information (OSTI.GOV)
Drake, R. P.; Keiter, P. A.; Kuranz, C. C.
This study discusses the recent research in High-Energy-Density Physics at our Center. Our work in complex hydrodynamics is now focused on mode coupling in the Richtmyer-Meshkov process and on the supersonic Kelvin-Helmholtz instability. These processes are believed to occur in a wide range of astrophysical circumstances. In radiation hydrodynamics, we are studying radiative reverse shocks relevant to cataclysmic variable stars. Our work on magnetized flows seeks to produce magnetized jets and study their interactions. We build the targets for all these experiments, and simulate them using our CRASH code. We also conduct diagnostic research, focused primarily on imaging x-ray spectroscopymore » and its applications to scattering and fluorescence.« less
An X-ray survey of nine historical novae. [HEAO 2 observations
NASA Technical Reports Server (NTRS)
Becker, R. H.; Marshall, F. E.
1980-01-01
The Einstein Observatory imaging proportional counter was used to search for X-ray emission from nine nearby historical novae. Six of the novae were detected with estimated X-ray intensities between .1 to 4 keV of 10 to the -13th power to 10 to the -11th power ergs/sq cm-s, comparable to the intensities of previously detected cataclysmic variables. The X-ray intensity of one of the novae, V603 Aql, varies over times of several hundred seconds. The data suggest a correlation between the decay rate of the historical outburst and the current X-ray luminosity. Alternatively, the X-ray luminosity may be related to the inclination of the binary system.
The large outbursts studied by small telescopes - the case of RS Oph
NASA Astrophysics Data System (ADS)
Kundra, E.; Hric, L.
2014-03-01
Cataclysmic variables (CVs) are one of the dominant part in astronomical research. Small telescopes are widely used to search for the sudden brightening of such stars. We present our experience with observations of the RS Ophiuchi (RS Oph) and analyses of the light curves. RS Oph is a binary system with 6 recorded outbursts classified as a recurrent nova (RN). We used the telescopes of AI SAS to measure the brightness of RS Oph after its last outburst occurred on February 12, 2006. The new observations indicate the ongoing mass transfer. % and the estimation of the mass transfer rate allow to make a prediction of the %next outburst of this RN.
Roche tomography of cataclysmic variables - VIII. The irradiated and spotted dwarf nova, SS Cygni
NASA Astrophysics Data System (ADS)
Hill, C. A.; Smith, Robert Connon; Hebb, L.; Szkody, P.
2017-12-01
We present the results of our spectroscopic study of the dwarf nova SS Cyg, using Roche tomography to map the stellar surface and derive the system parameters. Given that this technique takes into account the inhomogeneous brightness distribution on the surface of the secondary star, our derived parameters are (in principle) the most robust yet found for this system. Furthermore, our surface maps reveal that the secondary star is highly spotted, with strongly asymmetric irradiation on the inner hemisphere. Moreover, by constructing Doppler tomograms of several Balmer emission lines, we find strong asymmetric emission from the irradiated secondary star, and an asymmetric accretion disc that exhibits spiral structures.
Study of shock waves and related phenomena motivated by astrophysics
Drake, R. P.; Keiter, P. A.; Kuranz, C. C.; ...
2016-04-01
This study discusses the recent research in High-Energy-Density Physics at our Center. Our work in complex hydrodynamics is now focused on mode coupling in the Richtmyer-Meshkov process and on the supersonic Kelvin-Helmholtz instability. These processes are believed to occur in a wide range of astrophysical circumstances. In radiation hydrodynamics, we are studying radiative reverse shocks relevant to cataclysmic variable stars. Our work on magnetized flows seeks to produce magnetized jets and study their interactions. We build the targets for all these experiments, and simulate them using our CRASH code. We also conduct diagnostic research, focused primarily on imaging x-ray spectroscopymore » and its applications to scattering and fluorescence.« less
New Results on RZ Leo and CC Scl
NASA Astrophysics Data System (ADS)
Szkody, Paula; Mukadam, Anjum S.; Gaensicke, Boris T.; Toloza, Odette; Dai, Zhibin; HST GO12870 Team
2017-01-01
Using HST COS ultraviolet spectra in time-tag mode and a long K2 observation, we have determined a spin period for the white in RZ Leo of 220 seconds, thus confirming this cataclysmic variable as a new member of the Intermediate Polar class of systems. The ultraviolet light curve of CC Scl at quiescence created from its COS spectral observations is dominated by its spin period of 195 seconds (that has only been previously observed during one of its outbursts). Spectra formed from the high and low sections of its light curve shows a temperature difference of several thousand degrees.PS and ASM acknowledge support from NASA grant HST-GO13807 and from NSF grant AST-1514737.
SW Sextantis in an excited, low state
NASA Astrophysics Data System (ADS)
Groot, P. J.; Rutten, R. G. M.; van Paradijs, J.
2001-03-01
We present low-resolution spectrophotometric optical observations of the eclipsing nova-like cataclysmic variable SW Sex, the prototype of the SW Sex stars. We observed the system when it was in an unusual low state. The spectrum is characterized by the presence of strong Heii and Civ emission lines as well as the normal single peaked Balmer emission lines. The radial temperature profile of the disk follows the expected T~ R-3/4 only in the outer parts and flattens off inside 0.5 times the white dwarf Roche lobe radius. The single peaked emission lines originate in a region above the plane of the disk, at the position of the hot spot.
Probing the nature of cataclysmic variables via photometric studies on multiple timescales
NASA Astrophysics Data System (ADS)
Armstrong, Eve
I examine the structure and evolution of hydrogen- and helium-rich cataclysmic variables (CVs), via their periodic variability captured by long-term time series photometry. Studies to be discussed address one of two sets of question. One set pertains to helium CVs, which are poorly understood relative to their hydrogen-rich counterparts: What is the long-term evolution - in terms of orbital period (Porb) - of He CVs, and what does this imply about the nature of their secondaries? Two methods of investigation are employed: i) using systems with positive superhump and orbital period detections (Chapter 3) in order to chart the distribution of Porb versus time for He CVs (Chapter 4); ii) direct pulse timing of Porb in one system, via an 18-year baseline of photometry (Chapter 5). Results of the first study indicate that helium CVs are evolving toward longer Porb and have secondaries that are well described as degenerate objects. The pulse timing of one object (and the same measurement in two other He CVs) shows no evidence for Porb lengthening, and is consistent with Porb shortening driven by angular momentum loss via gravitational wave radiation. Technically, the two results are not inconsistent, as AM CVn is the only point on the distribution with a Porb timing. The apparent contradiction, however, illuminates our poor understanding of this class of CV: their routes to birth and the range of paths that a star can take following core hydrogen burning. The second set of studies pertains to signals associated with the accretion disc: Can a CV's accretion disc tilt with respect to the orbital plane? And what is the geometry and behavior of matter at various annuli in a tilted disc? To this end, I examine orbital sideband signals in AM CVn (Chapter 6) and simultaneous orbital sidebands and superorbital signals in two hydrogen CVs (Chapter 7). I also tabulate, from the literature, ten additional CVs with reliable detections of these signals (Chapter 7). All results indicate that the mechanism of tilt is at work in these objects.
Davis, Kevin C; Patel, Deesha; Rodes, Robert; Beistle, Diane
2016-01-01
Background In 2012, the US Centers for Disease Control and Prevention (CDC) launched Tips From Former Smokers (Tips), the first federally funded national tobacco education campaign. In 2013, a follow-up Tips campaign aired on national cable television networks, radio, and other channels, with supporting digital advertising to drive traffic to the Tips campaign website. Objective The objective of this study was to use geographic and temporal variability in 2013 Tips campaign television media doses and ad tagging to evaluate changes in traffic to the campaign website in response to specific doses of campaign media. Methods Linear regression models were used to estimate the dose-response relationship between weekly market-level television gross rating points (GRPs) and weekly Web traffic to the Tips campaign website. This relationship was measured using unique visitors, total visits, and page views as outcomes. Ad GRP effects were estimated separately for ads tagged with the Tips campaign website URL and 1-800-QUIT-NOW. Results In the average media market, an increase of 100 television GRPs per week for ads tagged with the Tips campaign website URL was associated with an increase of 650 unique visitors (P<.001), 769 total visits (P<.001), and 1255 total page views (P<.001) per week. The associations between GRPs for ads tagged with 1-800-QUIT-NOW and each Web traffic measure were also statistically significant (P<.001), but smaller in magnitude. Conclusions Based on these findings, we estimate that the 16-week 2013 Tips television campaign generated approximately 660,000 unique visitors, 900,000 total visits, and 1,390,000 page views for the Tips campaign website. These findings can help campaign planners forecast the likely impact of targeted advertising efforts on consumers’ use of campaign-specific websites. PMID:26887959
Parent health literacy and "obesogenic" feeding and physical activity-related infant care behaviors.
Yin, H Shonna; Sanders, Lee M; Rothman, Russell L; Shustak, Rachel; Eden, Svetlana K; Shintani, Ayumi; Cerra, Maria E; Cruzatte, Evelyn F; Perrin, Eliana M
2014-03-01
To examine the relationship between parent health literacy and "obesogenic" infant care behaviors. Cross-sectional analysis of baseline data from a cluster randomized controlled trial of a primary care-based early childhood obesity prevention program (Greenlight). English- and Spanish-speaking parents of 2-month-old children were enrolled (n = 844). The primary predictor variable was parent health literacy (Short Test of Functional Health Literacy in Adults; adequate ≥ 23; low <23). Primary outcome variables involving self-reported obesogenic behaviors were: (1) feeding content (more formula than breast milk, sweet drinks, early solid food introduction), and feeding style-related behaviors (pressuring to finish, laissez-faire bottle propping/television [TV] watching while feeding, nonresponsiveness in letting child decide amount to eat); and (2) physical activity (tummy time, TV). Multivariate logistic regression analyses (binary, proportional odds models) performed adjusting for child sex, out-of-home care, Women, Infants, and Children program status, parent age, race/ethnicity, language, number of adults/children in home, income, and site. Eleven percent of parents were categorized as having low health literacy. Low health literacy significantly increased the odds of a parent reporting that they feed more formula than breast milk, (aOR = 2.0 [95% CI: 1.2-3.5]), immediately feed when their child cries (aOR = 1.8 [1.1-2.8]), bottle prop (aOR = 1.8 [1.002-3.1]), any infant TV watching (aOR = 1.8 [1.1-3.0]), and inadequate tummy time (<30 min/d), (aOR = 3.0 [1.5-5.8]). Low parent health literacy is associated with certain obesogenic infant care behaviors. These behaviors may be modifiable targets for low health literacy-focused interventions to help reduce childhood obesity. Copyright © 2014 Mosby, Inc. All rights reserved.
Mota, Jorge; Gomes, Helena; Almeida, Mariana; Ribeiro, José Carlos; Santos, Maria Paula
2007-08-01
This study analyzes the relationships between leisure time physical activity (LTPA), sedentary behaviors, socioeconomic status, and perceived environmental variables. The sample comprised 815 girls and 746 boys. In girls, non-LTPA participants reported significantly more screen time. Girls with safety concerns were more likely to be in the non-LTPA group (OR = 0.60) and those who agreed with the importance of aesthetics were more likely to be in the active-LTPA group (OR = 1.59). In girls, an increase of 1 hr of TV watching was a significant predictor of non-LTPA (OR = 0.38). LTPA for girls, but not for boys, seems to be influenced by certain modifiable factors of the built environment, as well as by time watching TV.
Points of view: where do we look when we watch TV?
Brasel, S Adam; Gips, James
2008-01-01
How is our gaze dispersed across the screen when watching television? An exploratory eyetracker study with a custom-designed show indicated a very strong center-of-screen bias with gaze points following a roughly normal distribution peaked near screen center. Examining the show across time revealed that people were rarely all looking at the same location, and the amount of gaze dispersion within frames was highly variable. Different forms of programming yielded different levels of dispersion: static network 'bumpers' created the tightest visual groupings, and gaze dispersion for frames with show content was less than the dispersion for commercials. Advertising frames with brand logos generated higher dispersion than the non-branded advertisement portions, and repeated advertisements generated higher dispersion than their first-run counterparts.
[Smoking initiation and watching television, video, DVD among adolescents in Poland].
Kowalewska, Anna; Mazur, Joanna
2012-01-01
The aim of the study was to analyse the relationship between smoking initiation and the time spent watching TV, video, DVD by adolescents 11, 13, and 15-year-old in Poland. The research was conducted in 2010 as a part of Health Behaviour in School-aged Children: A WHO Collaborative Cross-national Study (HBSC) in a sample of 4751 students, using a standard, international HBSC questionnaire. It was found that there is a relationship between smoking attempts made by the young people and time spent watching TV during weekdays. In the analyzes using logistic regression combined variable relating to the time to watch TV on weekdays and weekends was used. Nearly a quarter of respondents (24.3%) were qualified to the group of adolescents spending too much time in front of the screen. Age was the strongest predictor of smoking onset. Between 11 and 13 years of age the risk of taking the first cigarette increased three times, and between 11 and 15 years of age more than seven times. Relative risk of smoking attempts related to gender and frequency of watching television, video or DVD was both equal to 1.5. In smoking prevention focused on adolescents it is should be better to pay more attention on constructive leisure time activities, and the role of parents in shaping pro-health attitudes. This is particularly important in the initial stages of schooling, when to develop and enhance the psychosocial competences as a the protective factor of risk taking behaviors among adolescents.
Schrempft, Stephanie; van Jaarsveld, Cornelia H. M.; Fisher, Abigail; Wardle, Jane
2015-01-01
Objectives The home environment is thought to play a key role in early weight trajectories, although direct evidence is limited. There is general agreement that multiple factors exert small individual effects on weight-related outcomes, so use of composite measures could demonstrate stronger effects. This study therefore examined whether composite measures reflecting the ‘obesogenic’ home environment are associated with diet, physical activity, TV viewing, and BMI in preschool children. Methods Families from the Gemini cohort (n = 1096) completed a telephone interview (Home Environment Interview; HEI) when their children were 4 years old. Diet, physical activity, and TV viewing were reported at interview. Child height and weight measurements were taken by the parents (using standard scales and height charts) and reported at interview. Responses to the HEI were standardized and summed to create four composite scores representing the food (sum of 21 variables), activity (sum of 6 variables), media (sum of 5 variables), and overall (food composite/21 + activity composite/6 + media composite/5) home environments. These were categorized into ‘obesogenic risk’ tertiles. Results Children in ‘higher-risk’ food environments consumed less fruit (OR; 95% CI = 0.39; 0.27–0.57) and vegetables (0.47; 0.34–0.64), and more energy-dense snacks (3.48; 2.16–5.62) and sweetened drinks (3.49; 2.10–5.81) than children in ‘lower-risk’ food environments. Children in ‘higher-risk’ activity environments were less physically active (0.43; 0.32–0.59) than children in ‘lower-risk’ activity environments. Children in ‘higher-risk’ media environments watched more TV (3.51; 2.48–4.96) than children in ‘lower-risk’ media environments. Neither the individual nor the overall composite measures were associated with BMI. Conclusions Composite measures of the obesogenic home environment were associated as expected with diet, physical activity, and TV viewing. Associations with BMI were not apparent at this age. PMID:26248313
NASA Astrophysics Data System (ADS)
Xie, Lei; Ma, Junhai
2016-09-01
In these days, as the recycling of household appliances becomes increasingly popular, the recycling network tends to be perfect in television industry. This paper focuses on the game among two recyclers and a processor in a Duopoly market of color TV recycling. We find that if the adjustment coefficients of the decision variables are changed abruptly, the system will fall into chaotic state. In order to avoid hazard of falling into a chaotic state, we adopt the method of delay control, providing the manufacturers with effective measures about chaos control. This paper analyzes the system's reactions to government decision, finding that when the parameters become beneficial for manufacturers, consumers and the environment, the system will fall into chaos and system's regional stability will reduce. Resulting from our analysis, this paper gives advice on the improvement of the environment and enhance in social welfare. Tested through the data we collected, this study is practical in both its theory and its applicability.
Allen, Mark S; Laborde, Sylvain; Walter, Emma E
2017-03-01
This prospective study explored the potential mediating role of health-related behavior (alcohol involvement, diet, television viewing, and physical activity) in the association between personality and change in memory performance over 2 years. A nationally representative sample of 8,376 U.K. participants aged 55 years and older (4,572 women, 3,804 men) completed self-report measures of personality and health-related behavior in 2010, and completed a memory performance task in 2010 and 2012. After removing variance associated with potential confounding variables, neuroticism and agreeableness had negative associations, and openness and conscientiousness positive associations with change in memory performance. There were no moderation effects by age, sex, education level, or ethnicity. Multiple mediator models demonstrated that physical activity, television viewing, and alcohol intake mediated associations between personality and change in memory performance. These findings provide evidence that the association between personality and memory performance in older adults can be explained, in part, through health-related behavior.
IUE observations of two late-type stars Bx Mon (M + pec) and TV Gem (M1 Iab)
NASA Technical Reports Server (NTRS)
Michalitsianos, A. G.; Hobbs, R. W.; Kafatos, M.
1981-01-01
The IUE observations of two late type stars BX Mon and TV Gem that reveal the emission properties in the ultraviolet of subluminous companions are discussed. Analysis of the continuum emission observed from BX Mon suggests the companion, is a middle A III star. High excitation emission lines observed between 1200 A and 2000 A that generally do not typify emission observed in either late M type variables or A type stars are also detected. It is suggested that these strong high excitation lines arise in a large volume of gas heated by nonradiation processes that could be the result of tidal interaction and mass exchange in the binary system. In contrast to stars such as BX Mon, the luminous M1 supergiant TV Gem shows unexpected intense UV continuum throughout the sensitivity range of IUE. The UV spectrum of TV Gem is characterized by intense continuum with broad absorption features detected in the short wavelength range. The analysis shows that the companion could be a B9 or A1 III-IV star. Alternate suggestions are presented for explaining the UV continuum in terms of an accretion disk in association with TV Gem.
Farrelly, Matthew C; Davis, Kevin C; Nonnemaker, James M; Kamyab, Kian; Jackson, Christine
2011-07-01
To understand the relative effectiveness of television advertisements that differ in their thematic focus and portrayals of negative emotions and/or graphic images in promoting calls to a smokers' quitline. Regression analysis is used to explain variation in quarterly media market-level per smoker calls to the New York State Smokers' Quitline from 2001 to 2009. The primary independent variable is quarterly market-level delivery of television advertisements measured by target audience rating points (TARPs). Advertisements were characterised by their overall objective--promoting cessation, highlighting the dangers of secondhand smoke (SHS) or other--and by their portrayals of strong negative emotions and graphic images. Per smoker call volume is positively correlated with total TARPs (p<0.001), and cessation advertisements are more effective than SHS advertisements in promoting quitline call volume. Advertisements with graphic images only or neither strong negative emotions nor graphic images are associated with higher call volume with similar effect sizes. Call volume was not significantly associated with the number of TARPs for advertisements with strong negative emotions only (p=0.71) or with both graphic images and strong emotions (p=0.09). Exposure to television advertisements is strongly associated with quitline call volume, and both cessation and SHS advertisements can be effective. The use of strong negative emotions in advertisements may be effective in promoting smoking cessation in the population but does not appear to influence quitline call volume. Further research is needed to understand the role of negative emotions in promoting calls to quitlines and cessation more broadly among the majority of smokers who do not call quitlines.
VizieR Online Data Catalog: Radial velocities of 35 cataclysmic variables (Thorstensen+, 2016)
NASA Astrophysics Data System (ADS)
Thorstensen, J. R.; Alper, E. H.; Weil, K. E.
2017-02-01
We present spectroscopic follow-up observations of 35 newly discovered cataclysmic variables (CVs), 32 of which were found by the Catalina Real Time Transient Surveys (CRTS; Drake et al. 2009, Cat. J/ApJ/696/870; Drake et al. 2014, Cat. J/MNRAS/441/1186; Breedt et al. 2014, Cat. J/MNRAS/443/3174), ASAS-SN (Shappee et al. 2014ApJ...788...48S), and/or MASTER (Lipunov et al. 2010AdAst2010E..30L). All our observations are from Michigan-Dartmouth-MIT (MDM) Observatory on Kitt Peak, Arizona. For nearly all the spectra, we used the "modspec" spectrograph (a description of the modspec can be found at http://mdm.kpno.noao.edu/Manuals/ModSpec/modspec_man.html) with a 600line/mm grating. We mostly used a SITe 20482 CCD detector, which yielded 2Å/pixel from 4210 to 7500Å, with declining throughput toward the ends of the spectral range. When this detector was unavailable, we used a very similar 10242 SITe detector ("Templeton"), which covered 4660 to 6730Å. The modspec was mounted mostly on the 2.4m Hiltner telescope, but for some of the brighter objects, we used the 1.3m McGraw-Hill telescope. For a few of the 1.3m spectra, we used the Mark III grism spectrograph, which covered 4580 to 6850Å at 2.3Å/pixel. On both telescopes and with both spectrographs, we used an Andor Ikon camera to view the reflective slit jaws through a microscope and guided the telescope with a separate off-axis guider. With this arrangement we could place any object that was bright enough for a usable spectrum in the slit and track it accurately even if the portion of the light spilling onto the slit jaws was invisible. Our emission-line radial velocities are almost entirely of Hα, since it almost always gives the best signal-to-noise ratio with our instrument. (3 data files).
Si, Jian-min; Luo, A-li; Wu, Fu-zhao; Wu, Yi-hong
2015-03-01
There are many valuable rare and unusual objects in spectra dataset of Sloan Digital Sky Survey (SDSS) Data Release eight (DR8), such as special white dwarfs (DZ, DQ, DC), carbon stars, white dwarf main-sequence binaries (WDMS), cataclysmic variable (CV) stars and so on, so it is extremely significant to search for rare and unusual celestial objects from massive spectra dataset. A novel algorithm based on Kernel dense estimation and K-nearest neighborhoods (KNN) has been presented, and applied to search for rare and unusual celestial objects from 546 383 stellar spectra of SDSS DR8. Their densities are estimated using Gaussian kernel density estimation, the top 5 000 spectra in descend order by their densities are selected as rare objects, and the top 300 000 spectra in ascend order by their densities are selected as normal objects. Then, KNN were used to classify the rest objects, and simultaneously K nearest neighbors of the 5 000 rare spectra are also selected as rare objects. As a result, there are totally 21 193 spectra selected as initial rare spectra, which include error spectra caused by deletion, redden, bad calibration, spectra consisting of different physically irrelevant components, planetary nebulas, QSOs, special white dwarfs (DZ, DQ, DC), carbon stars, white dwarf main-sequence binaries (WDMS), cataclysmic variable (CV) stars and so on. By cross identification with SIMBAD, NED, ADS and major literature, it is found that three DZ white dwarfs, one WDMS, two CVs with company of G-type star, three CVs candidates, six DC white dwarfs, one DC white dwarf candidate and one BL Lacertae (BL lac) candidate are our new findings. We also have found one special DA white dwarf with emission lines of Ca II triple and Mg I, and one unknown object whose spectrum looks like a late M star with emission lines and its image looks like a galaxy or nebula.
NASA Astrophysics Data System (ADS)
Godon, Patrick; Sion, Edward M.; Balman, Şölen; Blair, William P.
2017-09-01
The standard disk is often inadequate to model disk-dominated cataclysmic variables (CVs) and generates a spectrum that is bluer than the observed UV spectra. X-ray observations of these systems reveal an optically thin boundary layer (BL) expected to appear as an inner hole in the disk. Consequently, we truncate the inner disk. However, instead of removing the inner disk, we impose the no-shear boundary condition at the truncation radius, thereby lowering the disk temperature and generating a spectrum that better fits the UV data. With our modified disk, we analyze the archival UV spectra of three novalikes that cannot be fitted with standard disks. For the VY Scl systems MV Lyr and BZ Cam, we fit a hot inflated white dwarf (WD) with a cold modified disk (\\dot{M} ˜ a few 10-9 M ⊙ yr-1). For V592 Cas, the slightly modified disk (\\dot{M}˜ 6× {10}-9 {M}⊙ {{yr}}-1) completely dominates the UV. These results are consistent with Swift X-ray observations of these systems, revealing BLs merged with ADAF-like flows and/or hot coronae, where the advection of energy is likely launching an outflow and heating the WD, thereby explaining the high WD temperature in VY Scl systems. This is further supported by the fact that the X-ray hardness ratio increases with the shallowness of the UV slope in a small CV sample we examine. Furthermore, for 105 disk-dominated systems, the International Ultraviolet Explorer spectra UV slope decreases in the same order as the ratio of the X-ray flux to optical/UV flux: from SU UMa’s, to U Gem’s, Z Cam’s, UX UMa’s, and VY Scl’s.
X-ray reflection from cold white dwarfs in magnetic cataclysmic variables
NASA Astrophysics Data System (ADS)
Hayashi, Takayuki; Kitaguchi, Takao; Ishida, Manabu
2018-02-01
We model X-ray reflection from white dwarfs (WDs) in magnetic cataclysmic variables (mCVs) using a Monte Carlo simulation. A point source with a power-law spectrum or a realistic post-shock accretion column (PSAC) source irradiates a cool and spherical WD. The PSAC source emits thermal spectra of various temperatures stratified along the column according to the PSAC model. In the point-source simulation, we confirm the following: a source harder and nearer to the WD enhances the reflection; higher iron abundance enhances the equivalent widths (EWs) of fluorescent iron Kα1, 2 lines and their Compton shoulder, and increases the cut-off energy of a Compton hump; significant reflection appears from an area that is more than 90° apart from the position right under the point X-ray source because of the WD curvature. The PSAC simulation reveals the following: a more massive WD basically enhances the intensities of the fluorescent iron Kα1, 2 lines and the Compton hump, except for some specific accretion rate, because the more massive WD makes a hotter PSAC from which higher-energy X-rays are preferentially emitted; a larger specific accretion rate monotonically enhances the reflection because it makes a hotter and shorter PSAC; the intrinsic thermal component hardens by occultation of the cool base of the PSAC by the WD. We quantitatively estimate the influences of the parameters on the EWs and the Compton hump with both types of source. We also calculate X-ray modulation profiles brought about by the WD spin. These depend on the angles of the spin axis from the line of sight and from the PSAC, and on whether the two PSACs can be seen. The reflection spectral model and the modulation model involve the fluorescent lines and the Compton hump and can directly be compared to the data, which allows us to estimate these geometrical parameters with unprecedented accuracy.
NASA Astrophysics Data System (ADS)
Butters, O. W.; Katajainen, S.; Norton, A. J.; Lehto, H. J.; Piirola, V.
2009-03-01
Context: The origin, evolution, and ultimate fate of magnetic cataclysmic variables are poorly understood. It is largely the nature of the magnetic fields in these systems that leads to this poor understanding. Fundamental properties, such as the field strength and the axis alignment, are unknown in a majority of these systems. Aims: We undertake to put all the previous circular polarization measurements into context and systematically survey intermediate polars for signs of circular polarization, hence to get an indication of their true magnetic field strengths and try to understand the evolution of magnetic cataclysmic variables. Methods: We used the TurPol instrument at the Nordic Optical Telescope to obtain simultaneous UBVRI photo-polarimetric observations of a set of intermediate polars, during the epoch 2006 July 31-August 2. Results: Of this set of eight systems two (1RXS J213344.1+510725 and 1RXS J173021.5-055933) were found to show significant levels of circular polarization, varying with spin phase. Five others (V2306 Cyg, AO Psc, DQ Her, FO Aqr, and V1223 Sgr) show some evidence for circular polarization and variation of this with spin phase, whilst AE Aqr shows little evidence for polarized emission. We also report the first simultaneous UBVRI photometry of the newly identified intermediate polar 1RXS J173021.5-055933. Conclusions: Circular polarization may be ubiquitous in intermediate polars, albeit at a low level of one or two percent or less. It is stronger at longer wavelengths in the visible spectrum. Our results lend further support to the possible link between the presence of soft X-ray components and the detectability of circular polarization in intermediate polars. Based on observations obtained at the Nordic Optical Telescope at the Roque de los Muchachos Observatory in La Palma.
Malt Beverage Brand Popularity Among Youth and Youth-Appealing Advertising Content.
Xuan, Ziming; DeJong, William; Siegel, Michael; Babor, Thomas F
2017-11-01
This study examined whether alcohol brands more popular among youth are more likely to have aired television advertisements that violated the alcohol industry's voluntary code by including youth-appealing content. We obtained a complete list of 288 brand-specific beer advertisements broadcast during the National Collegiate Athletic Association (NCAA) men's and women's basketball tournaments from 1999 to 2008. All ads were rated by a panel of health professionals using a modified Delphi method to assess the presence of youth-appealing content in violation of the alcohol industry's voluntary code. The ads represented 23 alcohol brands. The popularity of these brands was operationalized as the brand-specific popularity of youth alcohol consumption in the past 30 days, as determined by a 2011 to 2012 national survey of underage drinkers. Brand-level popularity was used as the exposure variable to predict the odds of having advertisements with youth-appealing content violations. Accounting for other covariates and the clustering of advertisements within brands, increased brand popularity among underage youth was associated with significantly increased odds of having youth-appeal content violations in ads televised during the NCAA basketball tournament games (adjusted odds ratio = 1.70, 95% CI: 1.38, 2.09). Alcohol brands popular among underage drinkers are more likely to air television advertising that violates the industry's voluntary code which proscribes youth-appealing content. Copyright © 2017 by the Research Society on Alcoholism.
Grosso, Giuseppe; Marventano, Stefano; Nolfo, Francesca; Rametta, Stefania; Bandini, Lorenzo; Ferranti, Roberta; Bonomo, Maria Concetta; Matalone, Margherita; Galvano, Fabio; Mistretta, Antonio
2013-01-01
Lifestyle habits and parental modeling have been reported to influence adolescents food choices, such as for fruit and vegetable consumption. The aim of this study was to investigate the association be-tween personal eating (i. e. breakfast and snacking behavior), lifestyle (sedentary and physical activity), and family-related (i. e. consuming meals with parents, family rules, and television use) habits and fruit and vegetable consumption among adolescents living in Sicily, southern Italy. A cross-sectional survey was conducted across 14 schools in urban and rural areas, including 1,135 adolescents (12 - 14 years old). Validated instruments were used to assess possible relationships between the study variables and daily fruit and vegetable consumption. Higher parental education, occupation, and rural environment were positively associated with adolescents daily consumption of fruits and vegetables. Both types of food consumption were negatively associated with an increased frequency of between-meal and out-of-home eating, and positively with having meals with parents and higher parental influence in adolescents food choices. Television viewing habits were not related with adolescents vegetable consumption, whereas having a television in their room and commercial advertisings were negatively associated with daily intake of fruits. Although socioeconomic and cultural status may influence fruit and vegetable consumption, personal eating and family-related behaviors may be targeted for implementing recommendations.
Portrayals of reproductive and sexual health on prime-time television.
Pariera, Katrina L; Hether, Heather J; Murphy, Sheila T; Buffington, Sandra de Castro; Baezconde-Garbanati, Lourdes
2014-01-01
Prime-time broadcast television provides health information and establishes norms for millions of people in the United States (Beck, 2004; Brodie et al., 2001; Murphy & Cody, 2003; Rideout, 2008). To understand what people may be learning about reproductive and sexual health, a content analysis was conducted of story lines from the 10 most popular prime-time television programs in 2009, 2010, and 2011. Variables that were measured included the frequency of reproductive and sexual health issues, the level of health information, the type of information portrayed, the gain and loss frames, the presence of stigma, the tone, and the type of role model portrayed. Eighty-seven of the 589 health story lines dealt with reproductive and sexual health, and the most common issues were pre- and postterm pregnancy complications. The majority of these story lines had a moderate or weak level of information and included specifics about treatment and symptoms but not prevention. Just over half of the issues were framed in terms of losses, meaning nonadoption of a behavior change will result in negative outcomes. Twenty-four percent of reproductive and sexual health story lines involved stigma-usually stigma related to sexually transmitted infections (STIs). Most story lines were portrayed as serious and the majority of issues happened to positive role models. The implications of these portrayals for the viewing public are discussed.
Ceschini, Fabio L; Andrade, Douglas R; Oliveira, Luis C; Araújo Júnior, Jorge F; Matsudo, Victor K R
2009-01-01
To describe the prevalence of physical inactivity and associated factors among high school students from state's public schools in the city of São Paulo, state of São Paulo, Brazil. Sixteen state's public schools were randomly selected according to the geographic areas of the city (North, South, East, and West). The sample consisted of 3,845 high school students in 2006. Physical inactivity was measured using the International Physical Activity Questionnaire (short IPAQ) and was defined as practicing moderate and/or vigorous physical activity for a period of less than 300 minutes per week. The independent variables analyzed were: gender, age, socioeconomic level, geographic area of the city, awareness of the Agita São Paulo program, participation in physical education classes, smoking, alcohol intake and time spent per day watching television. Three-level Poisson regression was used for assessing the variables, with a significance level of p < 0.05. The general prevalence of physical inactivity among adolescents in São Paulo was 62.5% (95%CI 60.5-64.1). The factors associated with physical inactivity were gender, age, socioeconomic level, geographic area of the city, awareness of the Agita São Paulo program, non-participation in physical education classes, smoking, alcohol intake and time spent per day watching television. It was concluded that the prevalence of physical inactivity among adolescents in São Paulo was high in all the geographic areas evaluated, and that sociodemographic and behavioral factors contributed significantly to physical inactivity.
SKYLAB (SL)-3 - ASTRONAUT GARRIOTT, OWEN
1973-08-09
S73-32113 (9 Aug. 1973) --- Scientist-astronaut Owen K. Garriott, Skylab 3 science pilot, serves as test subject for the Skylab ?Human Vestibular Function? M131 Experiment, as seen in this photographic reproduction taken from a television transmission made by a color TV camera aboard the Skylab space station in Earth orbit. The objectives of the Skylab M131 experiment are to obtain data pertinent to establishing the validity of measurements of specific behavioral/physiological responses influenced by vestibular activity under one-g and zero-g conditions; to determine man?s adaptability to unusual vestibular conditions and predict habitability of future spacecraft conditions involving reduced gravity and Coriollis forces; and to measure the accuracy and variability in man?s judgment of spatial coordinates based on atypical gravity receptor cues and inadequate visual cues. Photo credit: NASA
Hargrave, Catriona; Deegan, Timothy; Bednarz, Tomasz; Poulsen, Michael; Harden, Fiona; Mengersen, Kerrie
2018-05-17
To describe a Bayesian network (BN) and complementary visualization tool that aim to support decision-making during online cone-beam computed tomography (CBCT)-based image-guided radiotherapy (IGRT) for prostate cancer patients. The BN was created to represent relationships between observed prostate, proximal seminal vesicle (PSV), bladder and rectum volume variations, an image feature alignment score (FAS TV _ OAR ), delivered dose, and treatment plan compliance (TPC). Variables influencing tumor volume (TV) targeting accuracy such as intrafraction motion, and contouring and couch shift errors were also represented. A score of overall TPC (FAS global ) and factors such as image quality were used to inform the BN output node providing advice about proceeding with treatment. The BN was quantified using conditional probabilities generated from published studies, FAS TV _ OAR /global modeling, and a survey of IGRT decision-making practices. A new IGRT visualization tool (IGRT REV ), in the form of Mollweide projection plots, was developed to provide a global summary of residual errors after online CBCT-planning CT registration. Sensitivity and scenario analyses were undertaken to evaluate the performance of the BN and the relative influence of the network variables on TPC and the decision to proceed with treatment. The IGRT REV plots were evaluated in conjunction with the BN scenario testing, using additional test data generated from retrospective CBCT-planning CT soft-tissue registrations for 13/36 patients whose data were used in the FAS TV _ OAR /global modeling. Modeling of the TV targeting errors resulted in a very low probability of corrected distances between the CBCT and planning CT prostate or PSV volumes being within their thresholds. Strength of influence evaluation with and without the BN TV targeting error nodes indicated that rectum- and bladder-related network variables had the highest relative importance. When the TV targeting error nodes were excluded from the BN, TPC was sensitive to observed PSV and rectum variations while the decision to treat was sensitive to observed prostate and PSV variations. When root nodes were set so the PSV and rectum variations exceeded thresholds, the probability of low TPC increased to 40%. Prostate and PSV variations exceeding thresholds increased the likelihood of repositioning or repeating patient preparation to 43%. Scenario testing using the test data from 13 patients, demonstrated two cases where the BN provided increased high TPC probabilities, despite some of the prostate and PSV volume variation metrics not being within tolerance. The IGRT REV tool was effective in highlighting and quantifying where TV and OAR variations occurred, supporting the BN recommendation to reposition the patient or repeat their bladder and bowel preparation. In another case, the IGRT REV tool was also effective in highlighting where PSV volume variation significantly exceeded tolerance when the BN had indicated to proceed with treatment. This study has demonstrated that both the BN and IGRT REV plots are effective tools for inclusion in a decision support system for online CBCT-based IGRT for prostate cancer patients. Alternate approaches to modeling TV targeting errors need to be explored as well as extension of the BN to support offline IGRT decisions related to adaptive radiotherapy. © 2018 American Association of Physicists in Medicine.
Sedentary behaviours and obesity in adults: the Cardiovascular Risk in Young Finns Study
Heinonen, I; Helajärvi, H; Pahkala, K; Heinonen, O J; Hirvensalo, M; Pälve, K; Tammelin, T; Yang, X; Juonala, M; Mikkilä, V; Kähönen, M; Lehtimäki, T; Viikari, J; Raitakari, O T
2013-01-01
Objective Sedentary behaviour may contribute to the development of obesity. We investigated the relations between different types of sedentary behaviour and adiposity markers in a well-characterised adult population after controlling for a wide range of potential confounders. Design Cross-sectional study. Setting The Cardiovascular Risk in Young Finns Multicenter Study. Participants Sedentary time (TV viewing, computer time, reading, music/radio listening and other relaxation) was assessed with a questionnaire for 1084 women and 909 men aged 30–45 years. Other study variables included occupational and leisure-time physical activity, sleep duration, socioeconomic status, smoking, alcohol consumption, energy intake, adherence to the recommended diet, multiple individual food items, age and genetic variants associated with body mass index (BMI). Primary outcome measures BMI in kg/m2 and waist circumference (WC in cm). Results Of the different sedentary behaviour types, TV viewing was most consistently related to higher BMI and WC, both in men and women. One additional daily TV hour was associated with a 1.81±0.44 cm larger WC in women and 2 cm±0.44 cm in men (both p<0.0001). The association with TV was diluted, but remained highly significant after adjustments with all measured covariates, including several potentially obesogenic food items associated with TV viewing. The intakes of food items such as sausage, beer and soft drinks were directly associated with TV viewing, while the intakes of oat and barley, fish, and fruits and berries were associated indirectly. After these adjustments, non-TV sedentary behaviour remained associated with adiposity indices only in women. Conclusions Out of the different types of sedentary behaviour, TV viewing was most consistently associated with adiposity markers in adults. Partial dilution of these associations after adjustments for covariates suggests that the obesogenic effects of TV viewing are partly mediated by other lifestyle factors. PMID:23794543
V1327 Aquilae: A New RR Lyrae variable with an extremely high radial velocity
NASA Astrophysics Data System (ADS)
Galeev, A. I.; Bikmaev, I. F.; Borisov, N. V.; Zhuchkov, R. Ya.; Shimanskii, V. V.; Khabibullina, M. L.; Sakhibullin, N. A.
2008-07-01
We have carried out photometry and spectroscopy of the star V1327 Aql ( R = 16 m ) as part of our program of observations of poorly studied cataclysmic variables using the 1.5-m optical Russian—Turkish telescope (RTT-150, Turkey) and the 6-m telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences. After analyzing our photometry, we have re-classified the variable as an RR Lyrae star. Our BV R photometry during 10 nights reveals brightness variations with the period 12h49m, with the B, V, and R amplitudes being 1.36 m , 1.13 m , and 1.11 m , respectively. We derived the first estimates of the star’s atmospheric parameters from our moderate-resolution spectra: T eff = 6280 K, log g = 3.3, [M/H] = -1.05. The extremely high radial velocity of the star’s motion ( V R = -470 km/s) and the star’s large distances to the Galactic center (13.1 kpc) and disk (4.2 kpc) testify to a probable extragalactic origin of this object.
Fahim, Germin; Toscani, Michael; Barone, Joseph A; Wang, Chris; Gandhi, Shivani
2018-01-01
The FDA's Presenting Risk Information draft guidance from May 2009 states that the time of risk versus benefit is a factor taken into consideration when evaluating audio and video direct-to-consumer (DTC) broadcasts. The objective of the study is to evaluate the proportion of risk narration on television (TV) advertisements in comparison to the actual proportion of serious adverse effects findings across select therapeutic areas. The study reviews prescription drug TV advertisements between the years 2010 and 2015 separated by therapeutic class. Indicators to assess risk versus benefit are as follows: total benefit time, total risk time, total ad time, percentage proportion of risk, and number of serious adverse effects (SAEs) listed in the package insert. The objective is establishing proportion of risk-to-benefit narration across therapeutic areas and the proportion of risk narration compared to the number of SAEs in the package insert. These outcomes will reflect whether TV advertisements abide by the "fair balance" rule and if the time spent on risk narrations is proportional to the number of SAEs across therapeutic areas. An analysis of risk versus benefit showed that there was a vast range of percentage differences in risk versus benefit narration across the products selected. The majority of the products narrated showed a 40% to 60% risk-to-benefit ratio. Six out of the 10 products evaluated communicated applicable black box warnings. There was variability among the SAE percentages presented between products. Lack of consistency exists between risks versus benefit proportions among different drug products.
Movahhed, Taraneh; Seifi, Safoura; Rashed Mohassel, Anousheh; Dorri, Mojtaba; Khorakian, Fateme; Mohammadzadeh, Zahra
2014-01-01
Today, electronic mass media such as television (TV), influence behavioral patterns of their audiences. This study aimed to evaluate what messages on food advertisements related to oral health were transmitted (appeals) and how they were transferred (performance methods & artistic techniques) in Islamic Republic of Iran Broadcasting (IRIB). In this cross sectional study, broadcasted advertisements on 4 important channels of Iran TV were recorded for a week from 8 am to 12 pm in 2012. The content and volume of food advertisements were investigated using a researcher-made check list. Advertisement group (food, non-food), food group (non-cariogenic, cariogenic), advertisement appeals (rational, emotional, and humor content), advertisement performance methods (hard-sell, soft-sell, presenting confirmation of Ministry of Health and Medical Education), and artistic technique were assessed. For variable comparison in groups a chi squared test and t-tests were used via SPSS software. Frequency of food advertisements (14.9%) were less than non-food advertising. Non-cariogenic food advertisements had higher frequency (12.09% (compared to cariogenic food (2.8%(. Rational appeal in advertising of non-cariogenic food had the most frequency (64.9%). In contrast emotional appeal for cariogenic food was used more frequently (85.5%). For cariogenic foods, a soft-sell approach was used more frequently (95.5%). The most common artistic technique used in food advertising was music. Chemical and mechanical dental plaque control materials had a very low frequency (0.2%). Advertising of cariogenic foods in Iran TV has low frequency.
Cataclysm No More: New Views on the Timing and Delivery of Lunar Impactors.
Zellner, Nicolle E B
2017-09-01
If properly interpreted, the impact record of the Moon, Earth's nearest neighbour, can be used to gain insights into how the Earth has been influenced by impacting events since its formation ~4.5 billion years (Ga) ago. However, the nature and timing of the lunar impactors - and indeed the lunar impact record itself - are not well understood. Of particular interest are the ages of lunar impact basins and what they tell us about the proposed "lunar cataclysm" and/or the late heavy bombardment (LHB), and how this impact episode may have affected early life on Earth or other planets. Investigations of the lunar impactor population over time have been undertaken and include analyses of orbital data and images; lunar, terrestrial, and other planetary sample data; and dynamical modelling. Here, the existing information regarding the nature of the lunar impact record is reviewed and new interpretations are presented. Importantly, it is demonstrated that most evidence supports a prolonged lunar (and thus, terrestrial) bombardment from ~4.2 to 3.4 Ga and not a cataclysmic spike at ~3.9 Ga. Implications for the conditions required for the origin of life are addressed.
Spectral types for objects in the Kiso survey. IV - Data for 81 stars
NASA Technical Reports Server (NTRS)
Wegner, Gary; Mcmahan, Robert K.
1988-01-01
Spectroscopy and spectral types for 81 ultraviolet-excess objects found in the Kiso Schmidt-camera survey are reported. The data were secured with the McGraw-Hill 1.3 m telescope at 8-A resolution covering the wavelength interval 4000 -7200 A using the Mark II spectrograph. Descriptions of the spectra of some of the more peculiar objects found in this sample are given and include 14 sub-dwarfs, 23 definite DA white dwarfs, including a magnetic one, and one DQ whie dwarf, eight quasars and emission-line objects, and a new composite DA + dM system. More spectroscopy of the new cataclysmic variable KUV 01584-0939 and a possibly related object is also described.
On the SW Sex-type eclipsing cataclysmic variable SDSS0756+0858
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tovmassian, Gagik; Hernandez, Mercedes Stephania; González-Buitrago, Diego
We conducted a spectroscopic and photometric study of SDSS J075653.11+085831. X-ray observations were also attempted. We determined the orbital period of this binary system to be 3.29 hr. It is a deep eclipsing system, whose spectra show mostly single-peaked, Balmer emission lines and a rather intense He II line. There is also the presence of faint (often double-peaked) He I emission lines as well as several absorption lines, Mg I being the most prominent. All of these features point toward the affiliation of this object with the growing number of SW Sex-type objects. We developed a phenomenological model of anmore » SW Sex system to reproduce the observed photometric and spectral features.« less
Optical spectrophotometry of oscillations and flickering in AE Aquarii
NASA Technical Reports Server (NTRS)
Welsh, William F.; Horne, Keith; Oke, J. B.
1993-01-01
We observed rapid variations in the nova-like cataclysmic variable AE Aquarii for 1.7 hr with 4.3 s time resolution using the 30-channel (3227-10494 A) spectrophotometer on the Hale 5 m telescope. The 16.5 and 33.0 s oscillations show a featureless blue spectrum that can be represented by a blackbody with temperature and area much smaller than the accretion disk. Models consisting of the sum of a K star spectrum and a hydrogen slab in LTE at T = 6000-10,000 K can fit the spectrum of AE Aquarii reasonably well. The spectrum of a flare indicates optically thin gas with T = 8000-12,000 K. The energy released by the flare is large compared to typical stellar flares.
Combined ultraviolet studies of astronomical source
NASA Technical Reports Server (NTRS)
Dupress, A. K.; Baliunas, S. L.; Blair, W. P.; Hartmann, L. W.; Huchra, J. P.; Raymond, J. C.; Smith, G. H.; Soderblom, D. R.
1985-01-01
As part of its Ultraviolet Studies of Astronomical Sources the Smithsonian Astrophysical Observatory for the period 1 Feb. 1985 to 31 July 1985 observed the following: the Cygnus Loop; oxygen-rich supernova remnants in 1E0102-72; the Large Magellanic Cloud supernova remnants; P Cygni profiles in dwarf novae; soft X-ray photoionization of interstellar gas; spectral variations in AM Her stars; the mass of Feige 24; atmospheric inhomogeneities in Lambda Andromedae and FF Aquarii; photometric and spectroscopic observation of Capella; Alpha Orionis; metal deficient giant stars; M 67 giants; high-velocity winds from giant stars; accretion disk parameters in cataclysmic variables; chromospheric emission of late-type dwarfs in visual binaries; chromospheres and transient regions of stars in the Ursa Major group; and low-metallicity blue galaxies.
Gebremariam, Mekdes K; Chinapaw, Mai J; Bringolf-Isler, Bettina; Bere, Elling; Kovacs, Eva; Verloigne, Maïté; Stok, F Marijn; Manios, Yannis; Brug, Johannes; Lien, Nanna
2017-01-01
The aim of the present study was to explore if children who spend more time on screen-based sedentary behaviors (i.e.TV viewing and computer use) drink more sugar-sweetened soft drinks. The study also assessed whether these associations were independent of individual and home environmental correlates of soft drink consumption and whether they were moderated by parental education. Data were collected from 7886 children participating in the EuropeaN Energy balance Research to prevent excessive weight Gain among Youth (ENERGY) survey conducted in eight European countries. Self-report questionnaires were used. Multilevel linear regression analyses with soft drink consumption as dependent variable, TV viewing and computer use as independent variables and age, gender, parental education, attitude towards soft drinks, self-efficacy, parental modelling, parental rules and home availability of soft drinks as covariates were conducted. Further interactions were tested to explore if these associations were moderated by parental education. Country-specific analyses were conducted. In six of the eight included countries, a significant positive association was observed between TV viewing (min/day) and soft drink consumption (ml/day), independent of individual and home environmental correlates of soft drink consumption (B = 0.46 (0.26-0.66) in Greece, B = 0.77 (0.36-1.17) in Norway, B = 0.82 (0.12-1.51) in Hungary, B = 1.06 (0.67-1.46) in Spain, B = 1.21 (0.67-1.74) in Belgium and B = 1.49 (0.72-2.27) in Switzerland). There was no significant association between computer use and soft drink consumption in six of the eight included countries in the final models. Moderation effects of parental education in the association between TV viewing and soft drink consumption were found in Norway and Hungary, the association being stronger among those with low parental education. TV viewing appears to be independently associated with soft drink consumption and this association was moderated by parental education in two countries only. Reducing TV time might therefore favorably impact soft drink consumption.
Gebremariam, Mekdes K.; Chinapaw, Mai J.; Bringolf-Isler, Bettina; Bere, Elling; Kovacs, Eva; Verloigne, Maïté; Stok, F. Marijn; Manios, Yannis; Brug, Johannes; Lien, Nanna
2017-01-01
Aim The aim of the present study was to explore if children who spend more time on screen-based sedentary behaviors (i.e.TV viewing and computer use) drink more sugar-sweetened soft drinks. The study also assessed whether these associations were independent of individual and home environmental correlates of soft drink consumption and whether they were moderated by parental education. Methods Data were collected from 7886 children participating in the EuropeaN Energy balance Research to prevent excessive weight Gain among Youth (ENERGY) survey conducted in eight European countries. Self-report questionnaires were used. Multilevel linear regression analyses with soft drink consumption as dependent variable, TV viewing and computer use as independent variables and age, gender, parental education, attitude towards soft drinks, self-efficacy, parental modelling, parental rules and home availability of soft drinks as covariates were conducted. Further interactions were tested to explore if these associations were moderated by parental education. Country-specific analyses were conducted. Results In six of the eight included countries, a significant positive association was observed between TV viewing (min/day) and soft drink consumption (ml/day), independent of individual and home environmental correlates of soft drink consumption (B = 0.46 (0.26–0.66) in Greece, B = 0.77 (0.36–1.17) in Norway, B = 0.82 (0.12–1.51) in Hungary, B = 1.06 (0.67–1.46) in Spain, B = 1.21 (0.67–1.74) in Belgium and B = 1.49 (0.72–2.27) in Switzerland). There was no significant association between computer use and soft drink consumption in six of the eight included countries in the final models. Moderation effects of parental education in the association between TV viewing and soft drink consumption were found in Norway and Hungary, the association being stronger among those with low parental education. Conclusions TV viewing appears to be independently associated with soft drink consumption and this association was moderated by parental education in two countries only. Reducing TV time might therefore favorably impact soft drink consumption. PMID:28182671
Nguyen, Hoang Thuy Linh; Seino, Kaoruko; Vo, Van Thang
2017-01-01
Background The rapid and widespread development of mass media sources including the Internet is occurring worldwide. Users are being confronted with a flood of health information through a wide availability of sources. Studies on how the availability of health information has triggered users’ interest in utilizing health care services remain limited within the Vietnamese population. Objective This study examined the associations between the wider availability of sources for health information and health care utilization in Vietnam after adjusting for potential confounding variables. Methods The data for this study were drawn from a cross-sectional study conducted over a 6-month period in Hue, a city in central Vietnam. The participants were 993 randomly selected adults aged between 18 and 60 years. Information was collected through face-to-face interviews on the types of information sources that were consulted, including traditional media (television), Internet, and health education courses, as well as the impact of such information on health care use (emergency department visits, hospitalizations, doctor visits). Multivariable logistic regression analyses were performed at a 95% confidence level. Results The prevalence of watching television, using the Internet, and attending health education courses to obtain health information were 50.9% (505/993), 32.9% (327/993), and 8.7% (86/993), respectively. After further adjustments for self-reported health status, the presence of health insurance, and monthly income, respondents who watched television and used the Internet to obtain health information were 1.7 times more likely to visit a doctor (television: adjusted odds ratio [AOR] 1.69, 95% CI 1.30-2.19; Internet: AOR 1.64, 95% CI 1.23-2.19), and also significantly associated with inpatient hospitalization (P=.003). Conclusions The use of widely available mass media sources (eg, television and the Internet) to obtain health information was associated with higher health care utilization. How this interest in health-related information can be used so that it will have a beneficial effect on care-seeking behavior should be a topic of concern to further health promotion in developing countries. PMID:29254911
Totland, Torunn H; Bjelland, Mona; Lien, Nanna; Bergh, Ingunn H; Gebremariam, Mekdes K; Grydeland, May; Ommundsen, Yngvar; Andersen, Lene F
2013-07-06
The present study investigated associations in gender dyads of parents' and adolescents' time spent on television and video viewing (TV/DVD), and computer and electronic game use (PC/games) at the ages of 11 and 13 years. Possible mediating effects of parental modelling and parental regulation in the relationship between parental education and adolescents' prospective TV/DVD and PC/game time were further examined. A total of 908 adolescents, participating at both ages 11 and 13 years in the Norwegian HEalth In Adolescents (HEIA) cohort study (2007-2009), were included in the analyses. Data on adolescents', mothers' and fathers' self reported time spent on TV/DVD and PC/games were measured at both time points by questionnaires. Correlation coefficients were used to examine gender dyads of parents' and adolescents' reports. Mediation analyses using linear regression investigated possible mediation effects of parental modelling and parental regulation in the prospective relationship between parental education and adolescents' time spent on TV/DVD and PC/games between the ages of 11 and 13 years. Correlations of screen time behaviours in gender dyads of parents and adolescents showed significant associations in time spent on TV/DVD at the age of 11 and 13 years. Associations between mothers and sons and between fathers and daughters were also observed in time spent on PC/games at the age of 11 years. Maternal and paternal modelling was further found to mediate the relationship between parental education and adolescents' prospective TV/DVD time between the ages of 11 and 13 years. No mediation effect was observed for parental regulation, however a decrease in both maternal and paternal regulation at the age of 11 years significantly predicted more TV/DVD time among adolescents at the age of 13 years. Cross-sectional and longitudinal relationships were observed in gender dyads of parents' and adolescents' screen time behaviours at the ages of 11 and 13 years, and further studies including both parents and their children should be emphasized. Moreover, maternal and paternal modelling were found to be important target variables in interventions aiming to reduce social differences by parental education in adolescents' prospective time spent on TV/DVD.
NASA Technical Reports Server (NTRS)
Mitchell, J. K.; Carrier, W. D., III; Houston, W. N.; Scott, R. F.; Bromwell, L. G.; Durgunoglu, H. T.; Hovland, H. J.; Treadwell, D. D.; Costes, N. C.
1972-01-01
Preliminary results are presented of an investigation of the physical and mechanical properties of lunar soil on the Descartes slopes, and the Cayley Plains in the vicinity of the LM for Apollo 16. The soil mechanics data were derived form (1) crew commentary and debriefings, (2) television, (3) lunar surface photography, (4) performance data and observations of interactions between soil and lunar roving vehicle, (5) drive-tube and deep drill samples, (6) sample characteristics, and (7) measurements using the SRP. The general characteristics, stratigraphy and variability are described along with the core samples, penetrometer test results, density, porosity and strength.
Musaiger, Abdulrahman O; Al-Mannai, Mariam
2014-03-01
Mass media play an important role in changing body image. This study aimed to determine the role of media (magazines and television) in body weight concern among university females in five Arab countries. A total sample of 1134 female university students was selected at convenience from universities in five Arab countries: Bahrain, Egypt, Jordan, Oman and Syria. The females' ages ranged from 17 to 32. A pre-tested questionnaire was used to assess the exposure to mass media regarding weight concerns. For the variables on exposure to mass media, girls were divided into two groups: infrequently exposed and frequently exposed. In general, the females who were exposed to mass media had a greater risk of having dieted to lose weight and changing their ideas of a perfect body shape than those who were not exposed or infrequently exposed. The association of exposure to magazines with having dieted to lose weight was only significant among females in Bahrain (p<0.044), Egypt (p<0.001) and Jordan (p<0.001). Exposure to television had a weaker association than exposure to magazines with body weight concerns of females. The association of exposure to television with females' idea of a perfect body shape was only statistically significant in females in Egypt (p<0.019) and Oman (p<0.019). The pressure from mass media on the body weight concern of female university students may lead these women to practise unhealthy weight control diets.
RW Sextantis, a disk with a hot, high-velocity wind
NASA Astrophysics Data System (ADS)
Greenstein, J. L.; Oke, J. B.
1982-07-01
The continuum spectrum of the flickering blue variable RW Sex was observed from 10,000 to 1150 A. The star is a cataclysmic variable currently stabilized at maximum, and the spectrum is dominated by an accretion disk, with flat spectrum in the ultraviolet, except at more than 5000 A, where a blackbody near 7000 K is seen. A distance of 400 pc is derived, if the latter arises from an F type main sequence star. The accretion rate required is near 10 to the -8th solar masses per year. Only weak emission is seen, except for Lyman alpha; strong, broad UV absorption lines are seen with centers displaced up to -3000 km/s, with terminal velocities up to -4500 km/s, the velocity of escape from a white dwarf. The low X-ray flux may arise from absorption within an unusually dense, hot wind from the innermost portions of the disk. The estimated mass loss rate is nearly 10 to the -12th solar masses per year.
RW Sextantis, a disk with a hot, high-velocity wind
NASA Technical Reports Server (NTRS)
Greenstein, J. L.; Oke, J. B.
1982-01-01
The continuum spectrum of the flickering blue variable RW Sex was observed from 10,000 to 1150 A. The star is a cataclysmic variable currently stabilized at maximum, and the spectrum is dominated by an accretion disk, with flat spectrum in the ultraviolet, except at more than 5000 A, where a blackbody near 7000 K is seen. A distance of 400 pc is derived, if the latter arises from an F type main sequence star. The accretion rate required is near 10 to the -8th solar masses per year. Only weak emission is seen, except for Lyman alpha; strong, broad UV absorption lines are seen with centers displaced up to -3000 km/s, with terminal velocities up to -4500 km/s, the velocity of escape from a white dwarf. The low X-ray flux may arise from absorption within an unusually dense, hot wind from the innermost portions of the disk. The estimated mass loss rate is nearly 10 to the -12th solar masses per year.
Reconstruction of the accretion disk in six cataclysmic variable stars
NASA Astrophysics Data System (ADS)
Rutten, R. G. M.; van Paradijs, J.; Tinbergen, J.
1992-07-01
The maximum-entropy eclipse-mapping algorithm is used to reconstruct images of the accretion disks of the novalike variable stars RW Tri, UX UMa, SW Sex, LX Ser, V 1315 Aql, and V363 Aur. The 2D disk intensity maps deduced from the light curves reveal the size of the disk and its radial intensity dependence. Black-body temperature maps deduced from the intensity maps at different wavelengths show that the disks in RW Tri, UX UMa, and V363 Aur have a radial temperature dependence which closely matches the fundamental theoretical run of the effective temperature with radial distance from disk center: T(eff) varies as R exp -3/4. The system V1315 Aql and SW Sex exhibit a much flatter run of T(R) in the inner region of the disk, while LX Ser appears to hold a position in between these two extremes. The consequences of these results for accretion disk models are also discussed.
Increasing Learning from TV News.
ERIC Educational Resources Information Center
Perloff, Richard M.; And Others
1982-01-01
Describes an experiment that manipulated two variables, repetition and pausing for viewer "digestion" of information in a news telecast. Concludes that the use of repetition increased viewers' retention of information, but that pauses did not. (FL)
Sex differences in facial emotion perception ability across the lifespan.
Olderbak, Sally; Wilhelm, Oliver; Hildebrandt, Andrea; Quoidbach, Jordi
2018-03-22
Perception of emotion in the face is a key component of human social cognition and is considered vital for many domains of life; however, little is known about how this ability differs across the lifespan for men and women. We addressed this question with a large community sample (N = 100,257) of persons ranging from younger than 15 to older than 60 years of age. Participants were viewers of the television show "Tout le Monde Joue", and the task was presented on television, with participants responding via their mobile devices. Applying latent variable modeling, and establishing measurement invariance between males and females and across age, we found that, for both males and females, emotion perception abilities peak between the ages of 15 and 30, with poorer performance by younger adults and declining performance after the age of 30. In addition, we show a consistent advantage by females across the lifespan, which decreases in magnitude with increasing age. This large scale study with a wide range of people and testing environments suggests these effects are largely robust. Implications are discussed.
Association Between Adolescent Viewership and Alcohol Advertising on Cable Television
Garfield, Craig F.; Elliott, Marc N.; Ostroff, Joshua; Ross, Craig; Jernigan, David H.; Vestal, Katherine D.; Schuster, Mark A.
2010-01-01
Objectives. We examined whether alcohol advertising on cable television is associated with adolescent viewership. Methods. Using Nielsen data for every national cable alcohol advertisement from 2001 to 2006 (608 591 ads), we examined whether ad incidence in a given advertising time slot was associated with adolescent viewership (i.e., the percentage of the audience that was aged 12–20 years) after we controlled for other demographic variables. Results. Almost all alcohol ads appeared in time slots with audiences made up of 30% or fewer underage viewers. In these time slots (standardized by duration and number of viewers), each 1-percentage-point increase in adolescent viewership was associated with more beer (7%), spirits (15%), and alcopop (or low-alcohol refresher; 22%) ads, but fewer wine (−8%) ads (P < .001 for all). For spirits and alcopops, associations were stronger among adolescent girls than among adolescent boys (P < .001 for each). Conclusions. Ad placements for beer, spirits, and alcopops increased as adolescent viewership rose from 0% to 30%, especially for female viewers. Alcohol advertising practices should be modified to limit exposure of underage viewers. PMID:19696391
Association between adolescent viewership and alcohol advertising on cable television.
Chung, Paul J; Garfield, Craig F; Elliott, Marc N; Ostroff, Joshua; Ross, Craig; Jernigan, David H; Vestal, Katherine D; Schuster, Mark A
2010-03-01
We examined whether alcohol advertising on cable television is associated with adolescent viewership. Using Nielsen data for every national cable alcohol advertisement from 2001 to 2006 (608 591 ads), we examined whether ad incidence in a given advertising time slot was associated with adolescent viewership (i.e., the percentage of the audience that was aged 12-20 years) after we controlled for other demographic variables. Almost all alcohol ads appeared in time slots with audiences made up of 30% or fewer underage viewers. In these time slots (standardized by duration and number of viewers), each 1-percentage-point increase in adolescent viewership was associated with more beer (7%), spirits (15%), and alcopop (or low-alcohol refresher; 22%) ads, but fewer wine (-8%) ads (P < .001 for all). For spirits and alcopops, associations were stronger among adolescent girls than among adolescent boys (P < .001 for each). Ad placements for beer, spirits, and alcopops increased as adolescent viewership rose from 0% to 30%, especially for female viewers. Alcohol advertising practices should be modified to limit exposure of underage viewers.
Religious practices and alcoholism in a southern adult population.
Koenig, H G; George, L K; Meador, K G; Blazer, D G; Ford, S M
1994-03-01
The study examined associations between religious variables and alcohol abuse and dependence among 2,969 North Carolina residents aged 18 to 97 who participated in the 1983-1984 National Institute of Mental Health Epidemiologic Catchment Area survey at its Piedmont location. Six-month and lifetime prevalence of alcohol disorders were compared among participants reporting varying levels of religious activity. Data were collected on frequency of Bible reading, prayer, and church attendance; time spent watching or listening to religious programming on television or radio; importance of religion; religious denomination; and identification as "born-again" Christians. Recent and lifetime alcohol disorders were less common among weekly churchgoers and those who considered themselves born again. Recent, but not lifetime, alcohol disorders were also less common among respondents who frequently read the Bible or prayed privately. Alcohol disorders were more common among those who frequently watched or listened to religious television and radio. Lifetime, but not recent, alcohol disorders were more prevalent among members of Pentecostal denominations. Longitudinal study is necessary to further clarify and explain these relationships between religious practices and alcohol disorders.
Television and eating: repetition enhances food intake
Mathur, Utsa; Stevenson, Richard J.
2015-01-01
Some studies find that eating with TV increases food intake while others do not. Some of this variability may reflect the engagingness of what is being watched (i.e., content). To test this we varied engagingness by manipulating content familiarity. Female participants undertook two sessions. In the “Different” session they watched two different episodes of the comedy Friends, with snack food presented during the second episode. In the “Same” session they viewed another episode of Friends twice in succession, with snack food presented during the second repeat showing. The three episodes of Friends used here were fully counterbalanced, so overall the only difference between the “Same” and “Different” sessions was whether the content of the second show was familiar or novel. As expected, 14% less was eaten in the “Different” session, suggesting that novel and presumably more engaging content can reduce intake relative to watching familiar and presumably less engaging content. These findings are consistent with the idea that the engagingness of TV can differentially affect food intake, although boredom or irritability resulting from repeat viewing might also explain this effect. PMID:26579040
Sims, Michelle; Salway, Ruth; Langley, Tessa; Lewis, Sarah; McNeill, Ann; Szatkowski, Lisa; Gilmore, Anna B
2014-06-01
To examine whether government-funded tobacco control television advertising shown in England between 2002 and 2010 reduced adult smoking prevalence and cigarette consumption. Analysis of monthly cross-sectional surveys using generalised additive models. England. More than 80 000 adults aged 18 years or over living in England and interviewed in the Opinions and Lifestyle Survey. Current smoking status, smokers' daily cigarette consumption, tobacco control gross rating points (GRPs-a measure of per capita advertising exposure combining reach and frequency), cigarette costliness, tobacco control activity, socio-demographic variables. After adjusting for other tobacco control policies, cigarette costliness and individual characteristics, we found that a 400-point increase in tobacco control GRPs per month, equivalent to all adults in the population seeing four advertisements per month (although actual individual-level exposure varies according to TV exposure), was associated with 3% lower odds of smoking 2 months later [odds ratio (OR) = 0.97, 95% confidence interval (CI) = 0.95, 0.999] and accounted for 13.5% of the decline in smoking prevalence seen over this period. In smokers, a 400-point increase in GRPs was associated with a 1.80% (95%CI = 0.47, 3.11) reduction in average cigarette consumption in the following month and accounted for 11.2% of the total decline in consumption over the period 2002-09. Government-funded tobacco control television advertising shown in England between 2002 and 2010 was associated with reductions in smoking prevalence and smokers' cigarette consumption. © 2014 The Authors. Addiction published by John Wiley & Sons Ltd on behalf of Society for the Study of Addiction.
Multi-Modal Glioblastoma Segmentation: Man versus Machine
Pica, Alessia; Schucht, Philippe; Beck, Jürgen; Verma, Rajeev Kumar; Slotboom, Johannes; Reyes, Mauricio; Wiest, Roland
2014-01-01
Background and Purpose Reproducible segmentation of brain tumors on magnetic resonance images is an important clinical need. This study was designed to evaluate the reliability of a novel fully automated segmentation tool for brain tumor image analysis in comparison to manually defined tumor segmentations. Methods We prospectively evaluated preoperative MR Images from 25 glioblastoma patients. Two independent expert raters performed manual segmentations. Automatic segmentations were performed using the Brain Tumor Image Analysis software (BraTumIA). In order to study the different tumor compartments, the complete tumor volume TV (enhancing part plus non-enhancing part plus necrotic core of the tumor), the TV+ (TV plus edema) and the contrast enhancing tumor volume CETV were identified. We quantified the overlap between manual and automated segmentation by calculation of diameter measurements as well as the Dice coefficients, the positive predictive values, sensitivity, relative volume error and absolute volume error. Results Comparison of automated versus manual extraction of 2-dimensional diameter measurements showed no significant difference (p = 0.29). Comparison of automated versus manual segmentation of volumetric segmentations showed significant differences for TV+ and TV (p<0.05) but no significant differences for CETV (p>0.05) with regard to the Dice overlap coefficients. Spearman's rank correlation coefficients (ρ) of TV+, TV and CETV showed highly significant correlations between automatic and manual segmentations. Tumor localization did not influence the accuracy of segmentation. Conclusions In summary, we demonstrated that BraTumIA supports radiologists and clinicians by providing accurate measures of cross-sectional diameter-based tumor extensions. The automated volume measurements were comparable to manual tumor delineation for CETV tumor volumes, and outperformed inter-rater variability for overlap and sensitivity. PMID:24804720
Correlates of screen time among 8-19-year-old students in China.
Ye, Sunyue; Chen, Lijian; Wang, Qineng; Li, Qinggong
2018-04-10
Previous studies have shown that prolonged time spent on screen-based sedentary behavior was significantly associated with lower health status in children, independent of physical activity levels. The study aimed to explore the individual and environmental correlates of screen time (ST) among 8-19-year-old students in China. The study surveyed ST using a self-administered questionnaire in Chinese students aged 8-19 years; 1063 participants were included in the final analysis. Individual and environmental correlates of ST were assessed using a mixed-effects model (for continuous outcome variables) and multiple logistic regression model (for binary outcome variables). Prolonged ST was observed in 14.7% of boys and 8.9% of girls. Of the ST, weekend and mobile phone/tablet use represented 80% and 40%, respectively. A positive relationship was observed between media accessibility and ST in both boys and girls (p < 0.05), whereas the presence of parents/others while using screens was a negative factor for longer ST (p < 0.05). Among the assessed correlates, access to a television (TV) in students' bedrooms was associated with prolonged total and weekend ST (p < 0.05 and p < 0.001, respectively). However, spending time on a mobile phone/tablet or a computer rather than viewing a TV, along with increased media accessibility, increased ST. These results indicate that greater media accessibility was positively associated and the presence of parents/others was negatively associated with prolonged ST in both Chinese boys and girls. Development of new and effective strategies against prolonged ST are required, especially for small screen device-based ST on weekends.
2012-01-01
Background Global obesity prevalence is increasing and population health programs are required to support changes to modifiable lifestyle risk factors. Such interventions benefit from mass-communications to promote their use. The Get Healthy Information and Coaching Service ® (GHS) utilised mass-reach media advertising to recruit participants to an Australian state-wide program. Methods A stand alone population survey collected awareness, knowledge and behavioural variables before the first advertising phase, (n = 1,544; August -September 2010), during (n = 1,500; February - March 2011) and after the advertising period (n = 1,500; June-July 2011). GHS usage data (n = 6,375) was collated during July 2010 – June 2011. Results The results showed that television-lead mass-media significantly increased unprompted awareness (0% to 31.8%, p < 0.001); prompted awareness (2.5% to 23.7%, p < 0.001); and understanding (10.2% to 32.2%, p < 0.001). Mass-media (television, print and mail out information) was more often cited as the source of referral by males, those aged 18 – 49 years, employed, and from the lowest socio-economic groups. During the weeks when mass-media advertising was present, 4 and 2.5 times more information and coaching participants respectively registered than when there was no advertising present. Participants who cited television and print were less likely to enrol in GHS coaching, but this was not the case for mail out information and secondary referral sources. Conclusions GHS mass-communications campaigns are effective at increasing awareness and usage of the GHS, especially among hard-to-reach population groups. Television advertising provides universal reach, but should be supplemented by health professional referrals and targeted mail-out information to recruit participants to the intensive GHS coaching program. PMID:22967230
Untersuchung der Mira-Sterne RT Boo, TV Peg und VX Aur
NASA Astrophysics Data System (ADS)
Raetz, Kerstin; Berthold, Thomas
2015-02-01
The light-change of the Mira stars RT Boo, TV Peg and VX Aur was analyzed on three ways for a long time. In the first period I estimated the brightness of the variables on sky monitoring photo plates (red spectral range) from Sonneberg Observatory with Argelander¥s Method, in the last years I measured scanned photo plates with a photometry program and in addition I used visual observations from A.A.V.S.O. for the analysis. The behavior of the periods of the tree stars from 1965 to 2013 is described here.
Küster, M
2004-06-01
Back pain and posture deficits get more common in childhood and adolescents. Lack of movement, insufficient physical education and high amounts of TV and PC are known as risk factors for chronic low back pain in later life. In a cross-sectional study, trunk muscle strength, posture and spinal flexibility were assessed in 200 untrained schoolchildren (117 girls, 83 boys). Independent variables, collected by a standardized questionnaire: age, height, weight, gender, weekly scope of TV, PC and sports (conditional, conditional-coordinative, coordinative). spinal parameter, tested by the Zebris CMS-System and IPN Back Check. PC and TV-consumption had negative effects on the spinal parameter, whereas esp. conditional-coordinative sports correlated positively. For general health and preventive reasons, children need a daily minimum of 30 minutes of movement. Conditional-coordinative sports are suited best because of their multifactorial load.
A radial velocity study of CTCV J1300-3052
NASA Astrophysics Data System (ADS)
Savoury, C. D. J.; Littlefair, S. P.; Marsh, T. R.; Dhillon, V. S.; Parsons, S. G.; Copperwheat, C. M.; Steeghs, D.
2012-05-01
We present time-resolved spectroscopy of the eclipsing, short-period cataclysmic variable CTCV J1300-3052. Using absorption features from the secondary star, we determine the radial velocity semi-amplitude of the secondary star to be K2= 378 ± 6 km s-1, and its projected rotational velocity to be v sin i= 125 ± 7 km s-1. Using these parameters and Monte Carlo techniques, we obtain masses of M1= 0.79 ± 0.05 M⊙ for the white dwarf primary and M2= 0.198 ± 0.029 M⊙ for the M-type secondary star. These parameters are found to be in good agreement with previous mass determinations found via photometric fitting techniques, supporting the accuracy and validity of photometric mass determinations in short-period CVs.
Discovery of an old nova shell surrounding the cataclysmic variable V1315 Aql
NASA Astrophysics Data System (ADS)
Sahman, D. I.; Dhillon, V. S.; Littlefair, S. P.; Hallinan, G.
2018-04-01
Following our tentative discovery of a faint shell around V1315 Aql reported in Sahman et al. (2015), we undertook deep Hα imaging and intermediate-resolution spectroscopy of the shell. We find that the shell has its geometric centre located on V1315 Aql. The mass, spectral features and density of the shell are consistent with other nova shells, rather than planetary nebulae or supernova remnants. The radial velocity of the shell is consistent with the systemic velocity of V1315 Aql. We believe this evidence strongly suggests that the shell originates from an earlier nova event. This is the first nova shell discovered around a novalike, and supports the theory of nova-induced cycles in mass transfer rates (hibernation theory) first proposed by Shara et al. (1986).
Discovery of an old nova shell surrounding the cataclysmic variable V1315 Aql
NASA Astrophysics Data System (ADS)
Sahman, D. I.; Dhillon, V. S.; Littlefair, S. P.; Hallinan, G.
2018-07-01
Following our tentative discovery of a faint shell around V1315 Aql reported in Sahman et al., we undertook deep Hα imaging and intermediate-resolution spectroscopy of the shell. We find that the shell has its geometric centre located on V1315 Aql. The mass, spectral features, and density of the shell are consistent with other nova shells, rather than planetary nebulae or supernova remnants. The radial velocity of the shell is consistent with the systemic velocity of V1315 Aql. We believe this evidence strongly suggests that the shell originates from an earlier nova event. This is the first nova shell discovered around a nova-like and supports the theory of nova-induced cycles in mass transfer rates (hibernation theory) first proposed by Shara et al.
Restablished Accretion in Post-outburst Classical Novae Revealed by X-rays
NASA Astrophysics Data System (ADS)
Hernanz, Margarita; Ferri, Carlo; Sala, Glòria
2009-05-01
Classical novae are explosions on accreting white dwarfs (hereinafter WDs) in cataclysmic variables (hereinafter CVs) a hydrogen thermonuclear runaway on top of the WD is responsible for the outburst. X-rays provide a unique way to study the turn-off of H-burning, because super soft X-rays reveal the hot WD photosphere, but also to understand how accretion is established again in the binary system. Observations with XMM-Newton of some post-outburst novae have revealed such a process, but a coverage up to larger energies -as Simbol-X will provide- is fundamental to well understand the characteristics of the binary system and of the nova ejecta. We present a brief summary of our results up to now and prospects for the Simbol-X mission.
Expected scientific performance of the three spectrometers on the extreme ultraviolet explorer
NASA Technical Reports Server (NTRS)
Vallerga, J. V.; Jelinsky, P.; Vedder, P. W.; Malina, R. F.
1990-01-01
The expected in-orbit performance of the three spectrometers included on the Extreme Ultraviolet Explorer astronomical satellite is presented. Recent calibrations of the gratings, mirrors and detectors using monochromatic and continuum EUV light sources allow the calculation of the spectral resolution and throughput of the instrument. An effective area range of 0.2 to 2.8 sq cm is achieved over the wavelength range 70-600 A with a peak spectral resolution (FWHM) of 360 assuming a spacecraft pointing knowledge of 10 arc seconds (FWHM). For a 40,000 sec observation, the average 3 sigma sensitivity to a monochromatic line source is 0.003 photons/sq cm s. Simulated observations of known classes of EUV sources, such as hot white dwarfs, and cataclysmic variables are also presented.
Nguyen, Hoang Thuy Linh; Nakamura, Keiko; Seino, Kaoruko; Vo, Van Thang
2017-12-18
The rapid and widespread development of mass media sources including the Internet is occurring worldwide. Users are being confronted with a flood of health information through a wide availability of sources. Studies on how the availability of health information has triggered users' interest in utilizing health care services remain limited within the Vietnamese population. This study examined the associations between the wider availability of sources for health information and health care utilization in Vietnam after adjusting for potential confounding variables. The data for this study were drawn from a cross-sectional study conducted over a 6-month period in Hue, a city in central Vietnam. The participants were 993 randomly selected adults aged between 18 and 60 years. Information was collected through face-to-face interviews on the types of information sources that were consulted, including traditional media (television), Internet, and health education courses, as well as the impact of such information on health care use (emergency department visits, hospitalizations, doctor visits). Multivariable logistic regression analyses were performed at a 95% confidence level. The prevalence of watching television, using the Internet, and attending health education courses to obtain health information were 50.9% (505/993), 32.9% (327/993), and 8.7% (86/993), respectively. After further adjustments for self-reported health status, the presence of health insurance, and monthly income, respondents who watched television and used the Internet to obtain health information were 1.7 times more likely to visit a doctor (television: adjusted odds ratio [AOR] 1.69, 95% CI 1.30-2.19; Internet: AOR 1.64, 95% CI 1.23-2.19), and also significantly associated with inpatient hospitalization (P=.003). The use of widely available mass media sources (eg, television and the Internet) to obtain health information was associated with higher health care utilization. How this interest in health-related information can be used so that it will have a beneficial effect on care-seeking behavior should be a topic of concern to further health promotion in developing countries. ©Hoang Thuy Linh Nguyen, Keiko Nakamura, Kaoruko Seino, Van Thang Vo. Originally published in the Journal of Medical Internet Research (http://www.jmir.org), 18.12.2017.
2014-01-01
Background Studies in youth highlight that moderate-to-vigorous physical activity (MVPA) and screen-time behaviours such as television viewing and PC use are associated with a range of health outcomes. However, little is known about recent trends in these behaviours in adolescents. This paper presents time trends in German adolescents’ television time, non-gaming PC use as well as MVPA from 2002 to 2010. Methods Data were derived from the cross-sectional German Health Behaviour in School-aged Children (HBSC) study in 2002, 2006 and 2010. Analyses were based on 16,918 11-to 15-year olds boys (49.1%) and girls. Outcome variables were time spent in TV viewing and using a PC (weekday and weekend day) as well as the number of days achieving 60 minutes of MVPA. Changes in both screen-time behaviours and MVPA over time were analysed using sex-specific linear regression, controlling for age and family affluence. Results TV viewing on weekdays, but not at weekends, declined steadily over time with a difference between 2002 and 2010 of 12.4 min/day in girls and 18.3 min/day in boys (p for trend < .01). We found a strong increase in PC use for non-gaming purposes over time for girls only, with a difference between 2002 and 2010 of 54.1 min/weekday and 68.8 min/weekend day (p < .001). For MVPA we found a slight statistically significant increase in terms of meeting PA guidelines as well as days/week in MVPA for boys and girls (p < .001). In 2010 14.0% of girls and 19.9% of boys met PA guideline. Conclusion Although MVPA increased from 2002 to 2010 in German adolescents, the time spent in MVPA was still low. Despite the observed decrease in TV viewing, there was no overall decline in the observed screen-based behaviours, especially for girls. This is mainly due to a marked increase in use of a PC for chatting on-line, internet, emailing, homework etc. among girls during the last ten years which outweighs the corresponding decrease in TV viewing. The findings highlight a need for strategies and interventions aimed at reducing screen-time behaviours and promoting MVPA. PMID:24725269
2013-01-01
Background The present study investigated associations in gender dyads of parents’ and adolescents’ time spent on television and video viewing (TV/DVD), and computer and electronic game use (PC/games) at the ages of 11 and 13 years. Possible mediating effects of parental modelling and parental regulation in the relationship between parental education and adolescents’ prospective TV/DVD and PC/game time were further examined. Methods A total of 908 adolescents, participating at both ages 11 and 13 years in the Norwegian HEalth In Adolescents (HEIA) cohort study (2007–2009), were included in the analyses. Data on adolescents’, mothers’ and fathers’ self reported time spent on TV/DVD and PC/games were measured at both time points by questionnaires. Correlation coefficients were used to examine gender dyads of parents’ and adolescents’ reports. Mediation analyses using linear regression investigated possible mediation effects of parental modelling and parental regulation in the prospective relationship between parental education and adolescents’ time spent on TV/DVD and PC/games between the ages of 11 and 13 years. Results Correlations of screen time behaviours in gender dyads of parents and adolescents showed significant associations in time spent on TV/DVD at the age of 11 and 13 years. Associations between mothers and sons and between fathers and daughters were also observed in time spent on PC/games at the age of 11 years. Maternal and paternal modelling was further found to mediate the relationship between parental education and adolescents’ prospective TV/DVD time between the ages of 11 and 13 years. No mediation effect was observed for parental regulation, however a decrease in both maternal and paternal regulation at the age of 11 years significantly predicted more TV/DVD time among adolescents at the age of 13 years. Conclusion Cross-sectional and longitudinal relationships were observed in gender dyads of parents’ and adolescents’ screen time behaviours at the ages of 11 and 13 years, and further studies including both parents and their children should be emphasized. Moreover, maternal and paternal modelling were found to be important target variables in interventions aiming to reduce social differences by parental education in adolescents’ prospective time spent on TV/DVD. PMID:23829607
Wang, An-Li; Ruparel, Kosha; Loughead, James W.; Strasser, Andrew A.; Blady, Shira J.; Lynch, Kevin G.; Romer, Dan; Cappella, Joseph N.; Lerman, Caryn; Langleben, Daniel D.
2013-01-01
Public service announcements (PSAs) are televised ads that are a key component of public health campaigns against smoking. Understanding the neurophysiological correlates of anti-tobacco ads is an important step towards novel objective methods of their evaluation and design. In the present study, we used Functional Magnetic Resonance Imaging (fMRI) to investigate the brain and behavioral effects of the interaction between content (“argument strength”) and format (“message sensation value”) of anti-smoking ads in human. Seventy-one non-treatment seeking smokers viewed a sequence of sixteen high or 16 low argument strength ads during a fMRI scan. Dependent variables were brain fMRI signal, the immediate recall of the ads, immediate change in Intentions to Quit Smoking and the urine levels of a major nicotine metabolite cotinine at a one-month follow-up. Whole brain ANOVA revealed that argument strength and message sensation value interacted in the inferior frontal, inferior parietal and fusiform gyri, the precuneus and the dorsomedial prefrontal cortex (dMPFC). Regression analysis showed that the activation in the dMPFC predicted lower cotinine levels a month later. These results characterize the key brain regions engaged in the processing of persuasive communications and suggest that brain fMRI response to anti-smoking ads could predict subsequent smoking severity in non-treatment seeking smokers. Our findings demonstrate the importance of the quality of ad content for objective ad outcomes and suggest that fMRI investigation may aid the pre-release evaluation of televised public health announcements. PMID:23616548
Slater, M D; Rouner, D; Murphy, K; Beauvais, F; Van Leuven, J; Rodríguez, M D
1996-07-01
This study examines white male adolescent responses to TV beer advertisements with and without sports content and to nonbeer ads when embedded in sports and entertainment programming. A total of 72 advertisements and 24 television program excerpts were randomly sampled from national television programming. White male adolescents (N = 157) recruited in a public school system each viewed six ads (one of each of three types of ad embedded in each of two types of programming) comprising the 2 x 2 x 3 factorial, within-subjects, mixed-model (random and fixed effects) experimental design along with an age-level blocking factor and random factors for commercial and program stimuli. Cognitive responses to each ad were content-analyzed. Individual difference variables including alcohol use behavior, sensation-seeking, masculinity and sports involvement were also measured. Subjects showed a consistent preference for beer ads with sports content. A significant three-way interaction between ad type, programming type and junior versus senior high-school age level also indicated that sports programming had an inconsistent effect on responses to beer ads but that nonbeer ads were responded to more positively during sports than during entertainment programming. Other analyses showed that subjects were more cognitively resistant to beer ads than to nonbeer ads. These results support public and official concerns that sports content in beer ads increase the ads appeal to underage youth. They do not support hypothesized concerns that sports programming might prime adolescents to be more receptive to beer ads. Implications for alcohol education efforts are discussed.
The relationship between self-report of depression and media usage
Block, Martin; Stern, Daniel B.; Raman, Kalyan; Lee, Sang; Carey, Jim; Humphreys, Ashlee A.; Mulhern, Frank; Calder, Bobby; Schultz, Don; Rudick, Charles N.; Blood, Anne J.; Breiter, Hans C.
2014-01-01
Depression is a debilitating condition that adversely affects many aspects of a person's life and general health. Earlier work has supported the idea that there may be a relationship between the use of certain media and depression. In this study, we tested if self-report of depression (SRD), which is not a clinically based diagnosis, was associated with increased internet, television, and social media usage by using data collected in the Media Behavior and Influence Study (MBIS) database (N = 19,776 subjects). We further assessed the relationship of demographic variables to this association. These analyses found that SRD rates were in the range of published rates of clinically diagnosed major depression. It found that those who tended to use more media also tended to be more depressed, and that segmentation of SRD subjects was weighted toward internet and television usage, which was not the case with non-SRD subjects, who were segmented along social media use. This study found that those who have suffered either economic or physical life setbacks are orders of magnitude more likely to be depressed, even without disproportionately high levels of media use. However, among those that have suffered major life setbacks, high media users—particularly television watchers—were even more likely to report experiencing depression, which suggests that these effects were not just due to individuals having more time for media consumption. These findings provide an example of how Big Data can be used for medical and mental health research, helping to elucidate issues not traditionally tested in the fields of psychiatry or experimental psychology. PMID:25309388
The relationship between self-report of depression and media usage.
Block, Martin; Stern, Daniel B; Raman, Kalyan; Lee, Sang; Carey, Jim; Humphreys, Ashlee A; Mulhern, Frank; Calder, Bobby; Schultz, Don; Rudick, Charles N; Blood, Anne J; Breiter, Hans C
2014-01-01
Depression is a debilitating condition that adversely affects many aspects of a person's life and general health. Earlier work has supported the idea that there may be a relationship between the use of certain media and depression. In this study, we tested if self-report of depression (SRD), which is not a clinically based diagnosis, was associated with increased internet, television, and social media usage by using data collected in the Media Behavior and Influence Study (MBIS) database (N = 19,776 subjects). We further assessed the relationship of demographic variables to this association. These analyses found that SRD rates were in the range of published rates of clinically diagnosed major depression. It found that those who tended to use more media also tended to be more depressed, and that segmentation of SRD subjects was weighted toward internet and television usage, which was not the case with non-SRD subjects, who were segmented along social media use. This study found that those who have suffered either economic or physical life setbacks are orders of magnitude more likely to be depressed, even without disproportionately high levels of media use. However, among those that have suffered major life setbacks, high media users-particularly television watchers-were even more likely to report experiencing depression, which suggests that these effects were not just due to individuals having more time for media consumption. These findings provide an example of how Big Data can be used for medical and mental health research, helping to elucidate issues not traditionally tested in the fields of psychiatry or experimental psychology.
Borzekowski, Dina L G; Robinson, Thomas N
2005-07-01
Media can influence aspects of a child's physical, social, and cognitive development; however, the associations between a child's household media environment, media use, and academic achievement have yet to be determined. To examine relationships among a child's household media environment, media use, and academic achievement. During a single academic year, data were collected through classroom surveys and telephone interviews from an ethnically diverse sample of third grade students and their parents from 6 northern California public elementary schools. The majority of our analyses derive from spring 2000 data, including academic achievement assessed through the mathematics, reading, and language arts sections of the Stanford Achievement Test. We fit linear regression models to determine the associations between variations in household media and performance on the standardized tests, adjusting for demographic and media use variables. The household media environment is significantly associated with students' performance on the standardized tests. It was found that having a bedroom television set was significantly and negatively associated with students' test scores, while home computer access and use were positively associated with the scores. Regression models significantly predicted up to 24% of the variation in the scores. Absence of a bedroom television combined with access to a home computer was consistently associated with the highest standardized test scores. This study adds to the growing literature reporting that having a bedroom television set may be detrimental to young elementary school children. It also suggests that having and using a home computer may be associated with better academic achievement.
Marketing strategy determinants in rural hospitals.
Smith, H L; Haley, D; Piland, N F
1993-01-01
Rural hospitals confront an inauspicious environment due to changes in patient reimbursement and medical practice. Facing a situation of declining revenues, marketing presents an option for rural hospitals to adapt to the growing constraints. This paper analyzes the determinants of marketing strategy emphasis in rural hospitals. The conceptual model adopted in this study predicts that prior performance and contextual variables explain marketing strategy emphasis. The relationships are examined in a case study of rural New Mexico hospitals. Results suggest that prior performance and several contextual variables explain variations in marketing strategy emphasis. In particular, higher gross patient revenues are associated with more emphasis on television and radio advertising. Furthermore, rural New Mexico hospitals with high numbers of licensed beds and medical staff members, or that are affiliated with a chain organization, place greater emphasis on market research and market planning. The implications for marketing practice in rural hospitals are discussed.
Alcohol warnings in TV beer advertisements.
Slater, M D; Domenech, M M
1995-05-01
Mandated warnings are among the few steps Congress has taken to influence the use of legal substances such as alcohol. The usefulness of such warnings in discouraging abuse of alcohol is, however, controversial. This study examines the impact of televised warnings on probable antecedents of belief change not examined in previous research: confidence in beliefs about beer risks or benefits, and cognitive responses to the advertisements. The present study (N = 75 male and female college students) tests four of the warnings recommended in Senate Bill 674 (1993--the "Thurmond bill") edited into randomly sampled television beer advertisements, using a between-subjects treatment-and-control experimental design. The four advertisements or advertisement/warning pairs were counterbalanced and analyzed as a repeated measures factor. The study indicated, as hypothesized, that subjects exposed to warnings tended to have less confidence in their generally skeptical assessments of beer risks--a likely precursor to belief change in resistant populations. Repeated exposure to the advertisements alone also appeared to lead to increased confidence in generally positive assessments of beer benefits, whereas repeated exposure to warnings led to decreased confidence in such assessments. Repeated exposure to warnings also may have primed negative reactions to subsequent beer advertisements. These results suggest mechanisms by which alcohol warnings may over time influence beliefs. Measures used here may serve as useful criterion variables in future studies on warnings. Further attention to optimizing warning content and presentation is recommended.
The sample of FBS cataclysmic variables
NASA Astrophysics Data System (ADS)
Mickaelian, Areg M.; Sinamyan, Parandzem K.
2013-02-01
abstract-type="normal"> The First Byurakan Survey (FBS) was conducted by Markarian et al. (1989) to reveal UV-excess galaxies. However, many other interesting objects were possible to detect based on its low-dispersion spectra, and the Second part of the FBS (Mickaelian 2008) was carried out later to reveal UV-excess stellar (point-like) objects, such as white dwarfs (WD), hot subdwarfs, cataclysmic variables (CV), HBB stars, as well as QSOs and Seyfert galaxies. In addition, the FBS plates were digitized (DFBS, Digitized First Byurakan Survey; Mickaelian et al. 2007) and the extraction and reduction of spectra allowed selection of objects with higher confidence and to fainter magnitudes. Spectroscopic observations have been carried out with three telescopes (Byurakan Astrophysical Observatory BAO-2.6m, Russian Special Astrophysical Observatory SAO-6m and Observatoire de Haute Provence OHP-1.93m) (Sinamyan & Mickaelian 2009) for classification of objects. The spectral features of CVs are narrow emission lines (Balmer series, HeI and HeII lines and Bowen band at 4640A) (Fig. 1). In addition, we use the NSVS database (Wozniak et al. 2004) for revealing variability and our method of comparison of POSS1 and POSS2 epoch photometric data (Mickaelian et al. 2011) based on accurate calculations of weighted average POSS1 and POSS2 magnitudes. 27 objects are present in the NSVS and light curves are available (Fig 2.). X-ray data may serve as an additional criterion to detect CVs among the FBS blue stellar objects (Voges et al. 1999; 2000). The subsample of FBS WDs has already been published (Sinamyan & Mickaelian 2011), where some CVs are also present. The subsample of FBS CVs consists of 38 objects, including the following types: dwarf novae (DN; UG and SU subtypes; 7 objects), nova-like variables (NL; SH, AC, VY subtypes; 11 objects), as well as there is a DQ Her type object (FBS 1140+719), a Helium CV (HeCV; FBS 1232+379), and a Low-mass X-ray Binary (LMXB; FBS 1656+354). Other objects do not have accurate classification because of the lack of photometric data. The Periods are in the range of 0.012 to 0.343 days. To make a complete study of these objects possible, multiwavelength (MW) data were retrieved for these 38 objects, including X-ray (ROSAT BSC and FSC), UV (GALEX), optical (APM, MAPS, USNO-B1.0, GSC 2.3.2, SDSS), and IR (2MASS, WISE, IRAS, AKARI) and MW SEDs were built. For CVs, MW SEDs have some disadvantage as their variability does not allow to have their accurate energy distribution. Diagrams with relations between MW data-points and some other physical parameters were also built.
XMM Astronomy Abundances Ages AGN Associations Asteroseismology Atomic_Data Binaries:cataclysmic astronomy) CDS cross-match service : fast cross-identification between any 2 tables, including VizieR
Theoretical size distribution of fossil taxa: analysis of a null model.
Reed, William J; Hughes, Barry D
2007-03-22
This article deals with the theoretical size distribution (of number of sub-taxa) of a fossil taxon arising from a simple null model of macroevolution. New species arise through speciations occurring independently and at random at a fixed probability rate, while extinctions either occur independently and at random (background extinctions) or cataclysmically. In addition new genera are assumed to arise through speciations of a very radical nature, again assumed to occur independently and at random at a fixed probability rate. The size distributions of the pioneering genus (following a cataclysm) and of derived genera are determined. Also the distribution of the number of genera is considered along with a comparison of the probability of a monospecific genus with that of a monogeneric family.
Parallaxes and Distance Estimates for Eleven Cataclysmic Binary Stars
NASA Astrophysics Data System (ADS)
Thorstensen, John R.; Lepine, S.; Shara, M.; Peters, C. S.
2007-12-01
We will present new distance estimates for eleven cataclysmic binary stars, based on trigonometric parallaxes measured with the 2.4m Hiltner telescope at MDM Observatory. The MDM parallaxes have typical uncertainties of 1 mas. A Bayesian formalism is used to find the most likely distance given the parallax, proper motion, and prior information. Results will be reported for the eclipsing dwarf nova HT Cas, for which our parallax favors a relatively short distance; KT Per, which proves to have a K-dwarf physical companion; the 65-minute double-degenerate system V396 Hya (CE 315); and the low accretion rate-polar MQ Dra (SDSS 1553). We gratefully acknowledge funding from the NSF through grants AST-9987334, AST-0307413, and AST-0708810.
Theory of magnetic cataclysmic binary X-ray sources
NASA Technical Reports Server (NTRS)
Lamb, Don Q.
1988-01-01
The theory of magnetic cataclysmic binary X-ray sources is reviewed. The physics of the accretion torque for disk and for stream accretion is described, and the magnetic field strengths of DQ Her stars inferred from their spin behavior and of AM Her stars from direct measurement are discussed. The implications of disk and stream accretion for the geometry of the emission region and for the X-ray pulse profiles are considered. The physicl properties of the X-ray emission region and the expected infrared, optical, soft X-ray, and hard X-ray spectra are described. The orientations of the magnetic moment in AM Her stars inferred from the circular and linear polarization of the optical light and the optical light curve are commented on.
The Palomar-Quest Synoptic Sky Survey
NASA Astrophysics Data System (ADS)
Mahabal, A.; Djorgovski, S. G.; Graham, M.; Williams, R.; Granett, B.; Bogosavljevic, M.; Baltay, C.; Rabinowitz, D.; Bauer, A.; Andrews, P.; Morgan, N.; Snyder, J.; Ellman, N.; Brunner, R.; Rengstorf, A. W.; Musser, J.; Gebhard, M.; Mufson, S.
2003-12-01
Exploration of the time domain is rapidly becoming one of the most exciting areas of astronomy. The Palomar-Quest synoptic sky survey has recently started producing a steady stream of data. In driftscan mode the survey covers Declination strips 4.6 deg wide, between -25 and +30 deg, at least twice in each of the two filter sets, one Johnson-Cousin's UBRI and one SDSS r'i'z'z', at a rate of about 500 square degrees per night. The scans are separated by time baselines of days to months, and we anticipate that they will extend to multi-year time scales over the next 3 to 5 years or beyond. The unprecedented amount of data makes this the largest synoptic survey of its kind both in terms of area covered and depth. We would search for both variable and transient objects, including supernovae, variable AGN, GRB orphan afterglows, cataclysmic variables, interesting stellar flares, novae, other types of variable stars, and possibly even entirely new types of objects or phenomena. We are in the process of designing a real-time data reduction pipeline which would enable a rapid discovery and spectroscopic follow-up of transients and other intersting objects. This survey can be seen as a precursor for the even larger synoptic sky surveys with LSST and PanSTARRS.
Gautam, Ramraj; Saito, Tami; Kai, Ichiro
2007-01-01
Background Involvement in activities has been found to be beneficial for improving quality of life and successful aging for older adults. Little is known, however, about the involvement in activities and depression of older adults in Asian developing countries. This study explores whether participation in leisure social and religious activities are related to depression and satisfaction with life in older adults of Nepal. Gender differences are also explored. Methods The study sample was derived from a survey which aimed to determine the intergenerational relationships between older adults and their married sons. A cross-sectional quantitative study of older adults sixty years and over in Nepal was conducted with face-to-face interviews using structured instruments. A convenience sample of 489 community dwelling older adults, 247 men and 242 women, were included in the study. The dependent variables, depression and satisfaction with life, were measured by the Geriatric Depression Scale (GDS) and Satisfaction With Life Scale (SWLS) respectively. Age, gender, marital status, education, perceived health, financial satisfaction, social support received and provided by older adults, and social activity were independent variables in the study. Results Saying prayers (B = -2.75; p < 0.005), watching television and listening to the radio (B = -1.88; p < 0.05), and participating in physical activity (B = -1.05; p < 0.05) correlated to lower depression for older men, but only watching television and listening to the radio (B = -2.68; p < 0.005) related to lower rates of depression for women. Socializing with others (B = 1.22; p < 0.05) was related to higher satisfaction with life for men, but for women visiting friends (B = 1.29; p < 0.05), socializing with others (B = 1.45; p < 0.005), and watching television and listening to the radio (B = 0.92; p < 0.05) related to improved satisfaction with life. Activity engagement significantly improved mental health in older adults. Conclusion Specific activity participation was a significant correlate of lower levels of depression and higher levels of satisfaction with life among older adults in Nepal. The findings explore the need for further research on activity participation in developing countries so that it can be useful for health care practioners and those involved with the activities of aged populations in developing countries. PMID:17953749
New Eclipsing Contact Binary System in Auriga
NASA Astrophysics Data System (ADS)
Austin, S. J.; Robertson, J. W.; Justice, C.; Campbell, R. T.; Hoskins, J.
2004-05-01
We present data on a newly discovered eclipsing binary system. The serendipitous discovery of this variable star was made by J.W. Robertson analyzing inhomogeneous ensemble photometry of stars in the field of the cataclysmic variable FS Aurigae from Indiana University RoboScope data. We obtained differential time-series BVR photometry during 2003 of this field variable using an ensemble of telescopes including the university observatories at ATU, UCA and joint ventures with amateur observatories in the state of Arkansas (Whispering Pines Observatory and Nubbin Ridge Observatory). The orbital period of this eclipsing system is 0.2508 days. The B-V light curve indicates colors of 1.2 around quadrature, to nearly 1.4 at primary eclipse. Binary star light curve models that best fit the BVR differential photometry suggest that the system is a contact binary overfilling the inner Roche Lobe by 12%, a primary component with a temperature of 4350K, a secondary component with a temperature of 3500K, a mass ratio of 0.37, and an inclination of 83 degrees. We present BVR light curves, an ephemeris, and best fit model parameters for the physical characteristics of this new eclipsing binary system.
Atlantis, Evan; Salmon, Jo; Bauman, Adrian
2008-11-01
The acute decision prompting effects of social marketing via television (TV) advertisements promoting physical activity to children are unknown. This pilot study aimed to determine the acute effects of an Australian government-sponsored TV advertisement (called 'Get Moving'), promoting more physical activity and less sedentary behaviour, on children's choices, preferences, and ratings of liking for physical activities and sedentary behaviours. Thirty-one children aged 10-12 years were recruited from a single public school, and randomised to one of two treatment groups or two control groups (Solomon four-group design). Treatment participants watched an episode of The Simpsons embedded every 10min with three 30s Get Moving advertisements plus standard advertisements. Control participants watched the same episode plus standard advertisements, but without the Get Moving advertisements. The following dependent variables were assessed immediately before and/or after exposure: activity preference (participants selected either verbally or by pointing to one of eight picture cards depicting four physical activities and four sedentary behaviours); ratings of liking (participants rated how much they liked or disliked each of these activities/behaviours either verbally or by pointing to one of nine values with an adjacent smile or frown on a Likert-type scale); and time spent in physical activities was assessed by direct observation during a 10min free-time session. No significant effects or trends were seen for any of the dependent variables. Further research is needed to determine whether different content and/or higher doses of exposure to physical activity promoting advertisements are needed to influence children's activity choices.
Effect of visual media use on school performance: a prospective study.
Sharif, Iman; Wills, Thomas A; Sargent, James D
2010-01-01
To identify mechanisms for the impact of visual media use on adolescents' school performance. We conducted a 24-month, four-wave longitudinal telephone study of a national sample of 6,486 youth aged 10 to 14 years. Exposure measures: latent construct for screen exposure time (weekday time spent viewing television/playing videogames, presence of television in bedroom) and variables for movie content (proportion of PG-13 and R movies viewed). self- and parent reports of grades in school. Effects of media exposures on change in school performance between baseline and 24 months were assessed using structural equation modeling. Information about hypothesized mediators (substance use, sensation seeking, and school problem behavior) was obtained at baseline and at the 16-month follow-up. Adjusted for baseline school performance, baseline levels of mediators, and a range of covariates, both screen exposure time and media content had adverse effects on change in school performance. Screen exposure had an indirect effect on poor school performance through increased sensation seeking. Viewing more PG-13 and R-rated movies had indirect effects on poor school performance mediated through increases in substance use and sensation seeking. R-rated viewing also had an indirect effect on poor school performance through increased school behavior problems. The effect sizes of exposure time and content on the intermediate variables and ultimately on school performance were similar to those for previously recognized determinants of these mediators, including household income, parenting style, and adolescents' self-control. These aspects of visual media use adversely affect school performance by increasing sensation seeking, substance use, and school problem behavior. Copyright 2010 Society for Adolescent Medicine. Published by Elsevier Inc. All rights reserved.
Effect of Visual Media Use on School Performance: A Prospective Study1
Sharif, Iman; Wills, Thomas A.; Sargent, James D.
2009-01-01
Purpose To identify mechanisms for the impact of visual media use on adolescents' school performance. Methods We conducted a 24-month, four-wave longitudinal telephone study of a national sample of 6,486 youth aged 10-14 years. Exposure Measures: Latent construct for screen exposure time (weekday time spent viewing television/playing videogames, presence of television in bedroom) and variables for movie content (proportion of PG13 and R movies viewed). Outcome Measure: Self and parent reports of grades in school. Effects of media exposures on change in school performance between baseline and 24 months were assessed using structural equation modeling. Information about hypothesized mediators (substance use, sensation-seeking, and school problem behavior) was obtained at baseline and at the16-month follow-up. Results Adjusted for baseline school performance, baseline levels of mediators, and a range of covariates, both screen exposure time and media content had adverse effects on change in school performance. Screen exposure had an indirect effect on poor school performance through increased sensation-seeking. Viewing more PG-13 and R-rated movies had indirect effects on poor school performance mediated through increases in substance use and sensation-seeking. R-rated viewing also had an indirect effect on poor school performance through increased school behavior problems. The effect sizes of exposure time and content on the intermediate variables and ultimately on school performance were similar to those for previously recognized determinants of these mediators – including household income, parenting style, and adolescents' self-control. Conclusions These aspects of visual media use adversely affect school performance by increasing sensation-seeking, substance use and school problem behavior. PMID:20123258
Kim, Sunny Jung; Niederdeppe, Jeff
2014-01-01
The authors conducted an experiment among U.S. college students (N = 115) to assess the effects of anger- and sadness-framed television antismoking advertisements on viewers' emotional response, impressions of the speaker, source likability, and empathy toward the speaker. The study was based on the fundamental assumptions of discrete emotions and was operationalized using the principles of universal facial expressions. The authors also constructed a path model to investigate how these variables predicted one's attitude toward smoking, attitude toward the tobacco industry, and intentions to smoke. Supporting study hypotheses, the anger-framed message increased the perceived dominance of the speaker relative to the other conditions. Perceived dominance, in turn, was negatively associated with smoking attitudes and, indirectly, smoking intentions. Contrary to study hypotheses, the sadness-framed message did not increase sad emotional responses, source likability, or empathy relative to the no emotion-framed message. The anger-framed message unexpectedly appeared to decrease these outcomes. Empathy and source likability were associated with positive attitudes toward the tobacco industry, but these attitudes did not predict intentions to smoke. The authors discuss the implications of these findings.
Leisure time activities of elementary school children.
Harrell, J S; Gansky, S A; Bradley, C B; McMurray, R G
1997-01-01
The three most common leisure time activities of 2,200 third and fourth grade children (mean age 8.8 + 0.8; 50.7% girls) and the association of the intensity levels of those activities with demographic variables and risk factors for cardiovascular disease are reported. Activities reported most often by boys were playing video games (33%), playing football (32%), bicycling (31%), watching television (28%), and playing basketball (26%). The girls reported doing homework (39%), bicycling (31%), watching television (30%), dancing (27%), and reading (23%). Overall, the children, especially girls, reported fairly sedentary activities, with an average metabolic equivalent level of 4.2 for girls and 4.8 for boys. Among boys, African Americans reported more vigorous activities than Whites, but the activities reported by White girls were somewhat more vigorous than those reported by non-White girls. Children from a higher socioeconomic status (SES), especially boys, reported a greater proportion of sedentary activities than lower SES children. The risk factors of cholesterol, blood pressure, skinfold thickness, and body mass index were not significantly associated with total activity score. However, significantly more nonobese than obese children reported a vigorous (high-intensity) activity as one of their top three activities.
Vecchiato, Giovanni; Maglione, Anton Giulio; Cherubino, Patrizia; Wasikowska, Barbara; Wawrzyniak, Agata; Latuszynska, Anna; Latuszynska, Malgorzata; Nermend, Kesra; Graziani, Ilenia; Leucci, Maria Rita; Trettel, Arianna; Babiloni, Fabio
2014-01-01
Neuromarketing is a multidisciplinary field of research whose aim is to investigate the consumers' reaction to advertisements from a neuroscientific perspective. In particular, the neuroscience field is thought to be able to reveal information about consumer preferences which are unobtainable through conventional methods, including submitting questionnaires to large samples of consumers or performing psychological personal or group interviews. In this scenario, we performed an experiment in order to investigate cognitive and emotional changes of cerebral activity evaluated by neurophysiologic indices during the observation of TV commercials. In particular, we recorded the electroencephalographic (EEG), galvanic skin response (GSR), and heart rate (HR) in a group of 28 healthy subjects during the observation of a series of TV advertisements that have been grouped by commercial categories. Comparisons of cerebral indices have been performed to highlight gender differences between commercial categories and scenes of interest of two specific commercials. Findings show how EEG methodologies, along with the measurements of autonomic variables, could be used to obtain hidden information to marketers not obtainable otherwise. Most importantly, it was suggested how these tools could help to analyse the perception of TV advertisements and differentiate their production according to the consumer's gender.
Maglione, Anton Giulio; Wasikowska, Barbara; Wawrzyniak, Agata; Graziani, Ilenia; Trettel, Arianna
2014-01-01
Neuromarketing is a multidisciplinary field of research whose aim is to investigate the consumers' reaction to advertisements from a neuroscientific perspective. In particular, the neuroscience field is thought to be able to reveal information about consumer preferences which are unobtainable through conventional methods, including submitting questionnaires to large samples of consumers or performing psychological personal or group interviews. In this scenario, we performed an experiment in order to investigate cognitive and emotional changes of cerebral activity evaluated by neurophysiologic indices during the observation of TV commercials. In particular, we recorded the electroencephalographic (EEG), galvanic skin response (GSR), and heart rate (HR) in a group of 28 healthy subjects during the observation of a series of TV advertisements that have been grouped by commercial categories. Comparisons of cerebral indices have been performed to highlight gender differences between commercial categories and scenes of interest of two specific commercials. Findings show how EEG methodologies, along with the measurements of autonomic variables, could be used to obtain hidden information to marketers not obtainable otherwise. Most importantly, it was suggested how these tools could help to analyse the perception of TV advertisements and differentiate their production according to the consumer's gender. PMID:25147579
Investigation of mechanisms linking media exposure to smoking in high school students.
Carson, Nicholas J; Rodriguez, Daniel; Audrain-McGovern, Janet
2005-08-01
Media exposure has been found to impact adolescent smoking, although the mechanisms of this relationship have not been thoroughly investigated. Drive for thinness and tobacco advertising receptivity, both shown to be associated with smoking, are two potential mediators. 967 twelfth grade students completed a self-report survey as part of a longitudinal study of biobehavioral predictors of smoking. Exposure to magazines and television, drive for thinness, tobacco advertisement receptivity, and twelfth grade smoking level were the primary variables of interest. Effects of gender, race, BMI, smoking exposure, and perceived physical appearance were controlled for in the model. Exposure to fashion, entertainment, and gossip magazines had indirect effects on smoking via drive for thinness and tobacco advertisement receptivity. There was a direct effect of health, fitness, and sports magazine reading on smoking. Television watching had no significant effects on smoking. Adolescents who read fashion, entertainment, and gossip magazines may be more likely to smoke, in part, because of a higher drive for thinness and greater receptivity to cigarette advertisements. Conversely, adolescents reading Health and Fitness magazines may be less likely to smoke. Drive for thinness and tobacco advertising receptivity are thus potential targets for adolescent smoking intervention.
The first search for variable stars in the open cluster NGC 6253 and its surrounding field
NASA Astrophysics Data System (ADS)
de Marchi, F.; Poretti, E.; Montalto, M.; Desidera, S.; Piotto, G.
2010-01-01
Aims: This work presents the first high-precision variability survey in the field of the intermediate-age, metal-rich open cluster NGC 6253. Clusters of this type are benchmarks for stellar evolution models. Methods: Continuous photometric monitoring of the cluster and its surrounding field was performed over a time span of ten nights using the Wide Field Imager mounted at the ESO-MPI 2.2 m telescope. High-quality timeseries, each composed of about 800 datapoints, were obtained for 250 000 stars using ISIS and DAOPHOT packages. Candidate members were selected by using the colour-magnitude diagrams and period-luminosity-colour relations. Membership probabilities based on the proper motions were also used. The membership of all the variables discovered within a radius of 8´ from the centre is discussed by comparing the incidence of the classes in the cluster direction and in the surrounding field. Results: We discovered 595 variables and we also characterized most of them providing their variability classes, periods, and amplitudes. The sample is complete for short periods: we classified 20 pulsating variables, 225 contact systems, 99 eclipsing systems (22 β Lyr type, 59 β Per type, 18 RS CVn type), and 77 rotational variables. The time-baseline hampered the precise characterization of 173 variables with periods longer than 4-5 days. Moreover, we found a cataclysmic system undergoing an outburst of about 2.5 mag. We propose a list of 35 variable stars as probable members of NGC 6253. ARRAY(0x383c870)
Mind the Gap when Data Mining the Ritter-Kolb Cataclysmic Variable Catalogue
NASA Astrophysics Data System (ADS)
Sparks, Warren M.; Sion, Edward M.
2017-01-01
The cataclysmic variable (CV) binary consists of a white dwarf primary and a low-mass secondary which overflows its Roche lobe. The Ritter-Kolb catalogue (2003, A&A, 404, 301) is a collection (~1000) of CV binaries and related objects. We have mined this catalogue for CVs with unevolved secondaries whose mass ratio (secondary/primary) is known (~130). A plot of the secondary mass verses the log of the orbital period exhibits the well-known period gap at 2-3 hrs. In addition, this plot shows that the secondary masses just above the period gap are collectively much larger than those just below. The average of the first ten secondary masses above the period is 180% larger than the average below the gap.The disrupted magnetic braking hypothesis (Howell, Nelson, and Rappaport 2001, ApJ, 550, 897 [HNR]) predicts that when the secondary becomes fully convective, the magnetic braking, which has driven the secondary out of thermal equilibrium, stops. In adjusting to thermal equilibrium the secondary shrinks below its Roche lobe and no longer loses mass. The binary system ceases to appear as a CV until gravitational radiation loss brings the secondary back in contact with its Roche lobe. This scenario is at odds with the apparent secondary mass loss across the period gap. Either the secondary continues to lose mass while crossing the period gap or the secondary masses are miscalculated!Magnetic braking causes the secondary to expand or inflate larger than its single star counterpart. Any orbital parameter calculation which assumes a radius-mass relationship based on single main-sequence stars will overestimate the mass of the secondary. We can approximate this mass overestimation from calculations by HNR which take into account the thermal heating from magnetic braking. Using this approximation as a first-order correction to the secondary mass, we replot the deflated secondary mass versus the binary period. The deflated masses immediately above and below the period gap are similar and do not indicate secondary mass loss across the gap. Thus, magnetic braking not only explains the period gap but the apparent secondary mass shift across it. Orbital parameters must be based upon actual secondary mass-radius observations.
1H 1752 + 081: An eclipsing cataclysmic variable with a small accretion disk
NASA Technical Reports Server (NTRS)
Silber, Andrew D.; Remillard, Ronald A.; Horne, Keith; Bradt, Hale V.
1994-01-01
We announce the discovery of an eclipsing nova-like cataclysmic variable (CV) as the optical counterpart to the HEAO 1 X-ray source 1H1752 + 081. This CV has an orbital period of 1.882801 hr, a high equivalent width of H-beta, and an average m(sub v) of 16.4 out of the eclipse. A geometric model is constructed from observations of the eclipse ingress and egress in many optical bandpasses. The broad-band emission originates primarily in two regions; the disk/accretion stream 'hot spot' and a compact central component, which may be a spot on the white dwarf surface, the entire white dwarf surface or the boundary layer between the accretion disk and the white dwarf surface. Based on the durations and offsets of the two eclipses we determined the mass ratio q = 2.5 +/- 0.6 and the angle of inclination i = 77 deg +/- 2 deg. If the central component is the entire white dwarf surface the masses of the stars are M(sub 1) = 0.80 +/- 0.06 solar masses and M(sub 2) = 0.32 +/- 0.06 solar masses. The disk is faint and small (R(sub D) = 0.25 +/- 0.05 r(sub L1), where r(sub L1) is the distance from the primary to the L(sub 1) point), compared to other eclipsing CVs. The small disk may result from the removal of angular momentum from the accretion disk by the magnetic field of the white dwarf; this CV may be a DQ Her type with a slowly rotating white dwarf. The emission-line velocities do not show the 'Z-wave' expected from the eclipse of a Keplerian accretion disk, nor do they have the correct phasing to originate near the white dwarf. The most likely origin of the line emission is the hot spot. The secondary star is visible at wavelengths greater than or equal to 6000 A during eclipse. We estimate a spectral type approximately M6 which, together with the observed m(sub 1) = 16.94 during eclipse, results in a distance estimate of 150 +/- 27 pc.
Broad-band characteristics of seven new hard X-ray selected cataclysmic variables
NASA Astrophysics Data System (ADS)
Bernardini, F.; de Martino, D.; Mukai, K.; Russell, D. M.; Falanga, M.; Masetti, N.; Ferrigno, C.; Israel, G.
2017-10-01
We present timing and spectral analysis of a sample of seven hard X-ray selected cataclysmic variable candidates based on simultaneous X-ray and optical observations collected with XMM-Newton, complemented with Swift/BAT and INTEGRAL /IBIS hard X-ray data and ground-based optical photometry. For six sources, X-ray pulsations are detected for the first time in the range of ˜296-6098 s, identifying them as members of the magnetic class. Swift J0927.7-6945, Swift J0958.0-4208, Swift J1701.3-4304, Swift J2113.5+5422 and possibly PBC J0801.2-4625 are intermediate polars (IPs), while Swift J0706.8+0325 is a short (1.7 h) orbital period polar, the 11th hard X-ray-selected identified so far. X-ray orbital modulation is also observed in Swift J0927.7-6945 (5.2 h) and Swift J2113.5+5422 (4.1 h). Swift J1701.3-4304 is discovered as the longest orbital period (12.8 h) deep eclipsing IP. The spectra of the magnetic systems reveal optically thin multitemperature emission between 0.2 and 60 keV. Energy-dependent spin pulses and the orbital modulation in Swift J0927.7-6945 and Swift J2113.5+5422 are due to intervening local high-density absorbing material (NH ˜ 1022 - 23 cm-2). In Swift J0958.0-4208 and Swift J1701.3-4304, a soft X-ray blackbody (kT ˜ 50 and ˜80 eV) is detected, adding them to the growing group of `soft' IPs. White dwarf masses are determined in the range of ˜ 0.58-1.18 M⊙, indicating massive accreting primaries in five of them. Most sources accrete at rates lower than the expected secular value for their orbital period. Formerly proposed as a long-period (9.4 h) nova-like CV, Swift J0746.3-1608 shows peculiar spectrum and light curves suggesting either an atypical low-luminosity CV or a low-mass X-ray binary.
The awakening of a classical nova from hibernation.
Mróz, Przemek; Udalski, Andrzej; Pietrukowicz, Paweł; Szymański, Michał K; Soszyński, Igor; Wyrzykowski, Łukasz; Poleski, Radosław; Kozłowski, Szymon; Skowron, Jan; Ulaczyk, Krzysztof; Skowron, Dorota; Pawlak, Michał
2016-09-29
Cataclysmic variable stars-novae, dwarf novae, and nova-likes-are close binary systems consisting of a white dwarf star (the primary) that is accreting matter from a low-mass companion star (the secondary). From time to time such systems undergo large-amplitude brightenings. The most spectacular eruptions, with a ten-thousandfold increase in brightness, occur in classical novae and are caused by a thermonuclear runaway on the surface of the white dwarf. Such eruptions are thought to recur on timescales of ten thousand to a million years. In between, the system's properties depend primarily on the mass-transfer rate: if it is lower than a billionth of a solar mass per year, the accretion becomes unstable and the matter is dumped onto the white dwarf during quasi-periodic dwarf nova outbursts. The hibernation hypothesis predicts that nova eruptions strongly affect the mass-transfer rate in the binary, keeping it high for centuries after the event. Subsequently, the mass-transfer rate should significantly decrease for a thousand to a million years, starting the hibernation phase. After that the nova awakes again-with accretion returning to the pre-eruption level and leading to a new nova explosion. The hibernation model predicts cyclical evolution of cataclysmic variables through phases of high and low mass-transfer. The theory gained some support from the discovery of ancient nova shells around the dwarf novae Z Camelopardalis and AT Cancri, but direct evidence for considerable mass-transfer changes prior, during and after nova eruptions has not hitherto been found. Here we report long-term observations of the classical nova V1213 Cen (Nova Centauri 2009) covering its pre- and post-eruption phases and precisely documenting its evolution. Within the six years before the explosion, the system revealed dwarf nova outbursts indicative of a low mass-transfer rate. The post-nova is two orders of magnitude brighter than the pre-nova at minimum light with no trace of dwarf nova behaviour, implying that the mass-transfer rate increased considerably as a result of the nova explosion.
The cataclysmic variables from the Palomar-Green survey
NASA Astrophysics Data System (ADS)
Ringwald, F. A.
1993-09-01
This thesis explores the cataclysmic variables (CVs) found by the Palomar-Green (PG) survey. This is the first compilation of a statistically complete sample of CVs found by ultraviolet color excess, and not outburst behavior. Blue and red follow-up spectrophotometry suggests that 22 of 68 objects classified originally as CVs are hot subdwarfs. Cool companions may be mimicking CVs' flat energy distributions, although the possibility remains that some are face-on CVs. Spectra taken with the International Ultraviolet Explorer satellite prove useful for distinguishing difficult cases. With the CV sample defined, the orbital periods for eleven systems are investigated with radial velocity studies. At 16th magnitude, CV number counts increase by 2.3 mag-1, although this may level off. The luminosity function is examined for the first time, and a trend toward higher space density at low luminosity is suspected. Outburst properties are compiled, and low-luminosity dwarf novae inflate the total space density to 6 x 10-6 pc-3. I describe all the PG CVs and candidate objects, and show spectra for most. This sample should be useful for population studies, such as measuring the space density with trigonometric parallaxes, or finding the fraction of eclipsing CVs. A new class of nova-likes, the SW Sextantis stars, is characterized by absorption events of the emission lines at spectroscopic phase 0.5, accompanied by large phase lags between the lightcurves and the radial velocity curves and strong high-excitation emission. There are at least six such CVs in this sample of 33, so this mysterious behavior must be common and not peculiar, as previously thought. Five of these six objects eclipse. Serendipitous results for individual CVs include finding low-frequency quasi-periodic variations in the radial velocity curve of the dwarf nova BZ Ursae Majoris. While erratic from epoch to epoch, these are too coherent to be pure noise. Another dwarf nova, HX Pegasi, is caught with time-resolved spectrophotometry on the rise to outburst. This is the second-ever such observation, and the first with red spectra. HX Pegasi is also confirmed as having a novel subdwarf-K red star.
VizieR Online Data Catalog: Cataclysmic Binaries, LMXBs, and related objects (Ritter+, 2003)
NASA Astrophysics Data System (ADS)
Ritter, H.; Kolb, U.
2004-03-01
Cataclysmic Binaries are semi-detached binaries consisting of a white dwarf or a white dwarf precursor primary and a low-mass secondary which is filling its critical Roche lobe. The secondary is not necessarily unevolved, it may even be a highly evolved star as for example in the case of the AM CVn-type stars. Low-Mass X-Ray Binaries are semi-detached binaries consisting of either a neutron star or a black hole primary, and a low-mass secondary which is filling its critical Roche lobe. Related Objects are detached binaries consisting of either a white dwarf or a white dwarf precursor primary and of a low-mass secondary. The secondary may also be a highly evolved star. The catalogue lists coordinates, apparent magnitudes, orbital parameters, stellar parameters of the components and other characteristic properties of 522 cataclysmic binaries, 75 low-mass X-ray binaries and 117 related objects with known or suspected orbital periods together with a comprehensive selection of the relevant recent literature. In addition the catalogue contains a list of references to published finding charts for 695 of the 714 objects. A cross-reference list of alias object designations concludes the catalogue. Literature published before 31 December 2003 has, as far as possible, been taken into account. This catalogue supersedes the 5th edition (catalogue ) and the updated lists by Ritter and Kolb (1995; catalogue ) (1998; catalogue ). (10 data files).
VizieR Online Data Catalog: Cataclysmic Binaries, LMXBs, and related objects (Ritter+, 2003)
NASA Astrophysics Data System (ADS)
Ritter, H.; Kolb, U.
2005-03-01
Cataclysmic Binaries are semi-detached binaries consisting of a white dwarf or a white dwarf precursor primary and a low-mass secondary which is filling its critical Roche lobe. The secondary is not necessarily unevolved, it may even be a highly evolved star as for example in the case of the AM CVn-type stars. Low-Mass X-Ray Binaries are semi-detached binaries consisting of either a neutron star or a black hole primary, and a low-mass secondary which is filling its critical Roche lobe. Related Objects are detached binaries consisting of either a white dwarf or a white dwarf precursor primary and of a low-mass secondary. The secondary may also be a highly evolved star. The catalogue lists coordinates, apparent magnitudes, orbital parameters, stellar parameters of the components and other characteristic properties of 572 cataclysmic binaries, 80 low-mass X-ray binaries and 142 related objects with known or suspected orbital periods together with a comprehensive selection of the relevant recent literature. In addition the catalogue contains a list of references to published finding charts for 761 of the 794 objects. A cross-reference list of alias object designations concludes the catalogue. Literature published before 31 December 2004 has, as far as possible, been taken into account. This catalogue supersedes the 5th edition (catalogue ) and the updated lists by Ritter and Kolb (1995; catalogue ) (1998; catalogue ). (10 data files).
NASA Technical Reports Server (NTRS)
Wilson, Robert M.
1999-01-01
During the contemporaneous interval of 1796-1882 a number of significant decreases in temperature are found in the records of Central England and Northern Ireland. These decreases appear to be related to the occurrences of El Nino and/or cataclysmic volcanic eruptions. For example, a composite of residual temperatures of the Central England dataset, centering temperatures on the yearly onsets of 20 El Nino of moderate to stronger strength, shows that, on average, the change in temperature varied by about +/- 0.3 C from normal being warmer during the boreal fall-winter leading up to the El Nino year and cooler during the spring-summer of the El Nino year. Also, the influence of El Nino on Central England temperatures appears to last about 1-2 years. Similarly, a composite of residual temperatures of the Central England dataset, centering temperatures on the month of eruption for 26 cataclysmic volcanic eruptions, shows that, on average, the change in temperature decreased by about 0.1 - 0.2 C, typically, 1-2 years after the eruption, although for specific events, like Tambora, the decrease was considerably greater. Additionally, tropical eruptions appear to produce greater changes in temperature than extratropical eruptions, and eruptions occurring in boreal spring-summer appear to produce greater changes in temperature than those occurring in fall-winter.
NASA Technical Reports Server (NTRS)
Wilson, Robert M.
2001-01-01
Since 1750, the number of cataclysmic volcanic eruptions (volcanic explosivity index (VEI)>=4) per decade spans 2-11, with 96 percent located in the tropics and extra-tropical Northern Hemisphere. A two-point moving average of the volcanic time series has higher values since the 1860's than before, being 8.00 in the 1910's (the highest value) and 6.50 in the 1980's, the highest since the 1910's peak. Because of the usual behavior of the first difference of the two-point moving averages, one infers that its value for the 1990's will measure approximately 6.50 +/- 1, implying that approximately 7 +/- 4 cataclysmic volcanic eruptions should be expected during the present decade (2000-2009). Because cataclysmic volcanic eruptions (especially those having VEI>=5) nearly always have been associated with short-term episodes of global cooling, the occurrence of even one might confuse our ability to assess the effects of global warming. Poisson probability distributions reveal that the probability of one or more events with a VEI>=4 within the next ten years is >99 percent. It is approximately 49 percent for an event with a VEI>=5, and 18 percent for an event with a VEI>=6. Hence, the likelihood that a climatically significant volcanic eruption will occur within the next ten years appears reasonably high.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-11-28
...] Digital Low Power Television, Television Translator, and Television Booster Stations and To Amend Rules... for Digital Low Power Television, Television Translator, and Television Booster Stations and to Amend... television, TV translator, and Class A television station DTV licensees''). The Commission has also revised...
Orbital design strategy for domestic communication satellite systems.
NASA Technical Reports Server (NTRS)
Ramji, S.; Sawitz, P.
1973-01-01
Review of some of the considerations pertinent to efficient orbit utilization in the design of domestic communications satellite systems. A strategy is developed to efficiently locate a heterogeneous system of satellites within the available arc and provide room for future growth. A practical design is illustrated, using a computer simulation model, for the placement of 25 satellites within 73% of the available arc employing frequency and polarization coordination techniques. A number of widely variable factors that influence satellite spacing are examined. These factors include such critical system elements as telephony and television interference noise limits, frequency plan coordination, polarization plan coordination, ground antenna diameter, signal protection ratio, and satellite station keeping.
Sociocultural influences and body image in 9- to 12-year-old girls: the role of appearance schemas.
Clark, Levina; Tiggemann, Marika
2007-03-01
This study tested whether an individual's beliefs about the importance of appearance in their life is a mediator of sociocultural influences on body dissatisfaction in young girls. Participants were 265 girls in Grades 4 to 7 (M age = 10.71 years) from 5 private primary schools in metropolitan Adelaide, South Australia. Girls completed questionnaire measures of appearance television and magazine exposure, peer appearance conversations, autonomy, appearance schemas, and body dissatisfaction. Appearance media exposure and peer appearance conversations were negatively related to body esteem, and autonomy positively predicted body esteem. Most important, appearance schemas mediated between all sociocultural variables and body dissatisfaction.
Code of Federal Regulations, 2013 CFR
2013-10-01
... television, television translators and television booster stations. 73.3521 Section 73.3521 Telecommunication..., television translators and television booster stations. When there is a pending application for a new low power television, television translator, or television booster station, or for major changes in an...
Code of Federal Regulations, 2012 CFR
2012-10-01
... television, television translators and television booster stations. 73.3521 Section 73.3521 Telecommunication..., television translators and television booster stations. When there is a pending application for a new low power television, television translator, or television booster station, or for major changes in an...
Code of Federal Regulations, 2011 CFR
2011-10-01
... television, television translators and television booster stations. 73.3521 Section 73.3521 Telecommunication..., television translators and television booster stations. When there is a pending application for a new low power television, television translator, or television booster station, or for major changes in an...
Code of Federal Regulations, 2014 CFR
2014-10-01
... television, television translators and television booster stations. 73.3521 Section 73.3521 Telecommunication..., television translators and television booster stations. When there is a pending application for a new low power television, television translator, or television booster station, or for major changes in an...
Code of Federal Regulations, 2010 CFR
2010-10-01
... television, television translators and television booster stations. 73.3521 Section 73.3521 Telecommunication..., television translators and television booster stations. When there is a pending application for a new low power television, television translator, or television booster station, or for major changes in an...
Abbas, Ozan Luay; Karadavut, Ufuk
2017-12-01
Cosmetic surgery is no longer just for females. More men are opting for cosmetic procedures, with marked increases seen in both minimally invasive and surgical options over the last decade. Compared to females, relatively little work has specifically focused on factors predicting males' attitudes toward cosmetic surgery. Therefore, we evaluated a number of variables that may predict some facet of men's attitudes toward cosmetic surgery according to evidence reported in the literature METHODS: A total of 151 male patients who applied for a surgical or minimally invasive cosmetic surgery procedure (patient group) and 151 healthy male volunteers who do not desire any type of cosmetic procedure (control group) were asked to fill out questionnaires about measures of body image, media exposure (television and magazine), social network site use, masculine gender role stress and religious attitudes. Our findings showed that lower ratings of body image satisfaction, increased time spent watching television, more frequent social network site use and higher degrees of masculine gender role stress were all significant predictors of attitudes toward cosmetic surgery among males. The current study confirmed the importance of body image dissatisfaction as a predictor of the choice to undergo cosmetic procedure. More importantly, a new predictor of cosmetic procedure attitudes was identified, namely masculine gender role stress. Finally, we demonstrated the effects television exposure and social network site use in promoting acceptance of surgical and nonsurgical routes to appearance enhancement. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .
Hakala, Paula T; Rimpelä, Arja H; Saarni, Lea A; Salminen, Jouko J
2006-10-01
Neck-shoulder pain (NSP) and low back pain (LBP) increased among adolescents in the 1990s and the beginning of 2000. A potential risk factor for this increase is the use of information and communication technology. We studied how the use of computers, the Internet, and mobile phones, playing digital games and viewing television are related to NSP and LBP in adolescents. Mailed survey with nationally representative samples of 14-, 16-, and 18-year-old Finns in 2003 (n = 6003, response rate 68%). The outcome variables were weekly NSP and LBP. NSP was perceived by 26% and LBP by 12%. When compared with non-users, the risk of NSP was 1.3 (adjusted odds ratios) when using computers > 2-3 h/day, and 1.8 when using 4-5 h/day; 2.5 when using computers > or = 42 h/week, and 1.7 when using the Internet > or = 42 h/week. Compared with non-users, the risk of LBP was 2.0 when using computers > 5 h/day, 1.7 when using > or = 42 h/week, 1.8 when using the Internet > or = 42 h/week, and 2.0 when playing digital games > 5 h/day. Times spent on digital gaming, viewing television, and using mobile phones were not associated with NSP, nor were use of mobile phones and viewing television with LBP after adjusting for confounding factors. Frequent computer-related activities are an independent risk factor for NSP and LBP. Daily use of computers exceeding 2-3 h seems to be a threshold for NSP and exceeding 5 h for LBP. Computer-related activities may explain the increase of NSP and LBP in the 1990s and the beginning of 2000.
Managing Risks? Early Warning Systems for Climate Change
NASA Astrophysics Data System (ADS)
Sitati, A. M.; Zommers, Z. A.; Habilov, M.
2014-12-01
Early warning systems are a tool with which to minimize risks posed by climate related hazards. Although great strides have been made in developing early warning systems most deal with one hazard, only provide short-term warnings and do not reach the most vulnerable. This presentation will review research results of the United Nations Environment Programme's CLIM-WARN project. The project seeks to identify how governments can better communicate risks by designing multi-hazard early warning systems that deliver actionable warnings across timescales. Household surveys and focus group discussions were conducted in 36 communities in Kenya, Ghana and Burkina Faso in order to identify relevant climate related hazards, current response strategies and early warning needs. Preliminary results show significant variability in both risks and needs within and between countries. For instance, floods are more frequent in rural western parts of Kenya. Droughts are frequent in the north while populations in urban areas face a range of hazards - floods, droughts, disease outbreaks - that sometimes occur simultaneously. The majority of the rural population, especially women, the disabled and the elderly, do not have access to modern media such as radio, television, or internet. While 55% of rural populace never watches television, 64% of urban respondents watch television on a daily basis. Communities have different concepts of how to design warning systems. It will be a challenge for national governments to create systems that accommodate such diversity yet provide standard quality of service to all. There is a need for flexible and forward-looking early warning systems that deliver broader information about risks. Information disseminated through the system could not only include details of hazards, but also long-term adaptation options, general education, and health information, thus increasingly both capabilities and response options.