746 research outputs found
Emotions and Digital Well-being. The rationalistic bias of social media design in online deliberations
In this chapter we argue that emotions are mediated in an incomplete way in online social media because of the heavy reliance on textual messages which fosters a rationalistic bias and an inclination towards less nuanced emotional expressions. This incompleteness can happen either by obscuring emotions, showing less than the original intensity, misinterpreting emotions, or eliciting emotions without feedback and context. Online interactions and deliberations tend to contribute rather than overcome stalemates and informational bubbles, partially due to prevalence of anti-social emotions. It is tempting to see emotions as being the cause of the problem of online verbal aggression and bullying. However, we argue that social media are actually designed in a predominantly rationalistic way, because of the reliance on text-based communication, thereby filtering out social emotions and leaving space for easily expressed antisocial emotions. Based on research on emotions that sees these as key ingredients to moral interaction and deliberation, as well as on research on text-based versus non-verbal communication, we propose a richer understanding of emotions, requiring different designs of online deliberation platforms. We propose that such designs should move from text-centred designs and should find ways to incorporate the complete expression of the full range of human emotions so that these can play a constructive role in online deliberations
Relationship of sleep quality and health-related quality of life in adolescents according to self- and proxy ratings: a questionnaire survey
Roeser K, Eichholz R, Schwerdtle B, Schlarb A, Kübler A. Relationship of sleep quality and health-related quality of life in adolescents according to self- and proxy ratings: a questionnaire survey. Front Psychiatry. 2012;3:76:76.Introduction: Sleep disturbances are common in adolescents and adversely affect performance, social contact, and susceptibility to stress. We investigated the hypothesis of a relationship between sleep and health-related quality of life (HRQoL), and applied self- and proxy ratings. Materials and Methods: The sample comprised 92 adolescents aged 11–17 years. All participants and their parents completed a HRQoL measure and the Sleep Disturbance Scale for Children (SDSC). Children with SDSC T-scores above the normal range (above 60) were classified as poor sleepers. Results: According to self- and proxy ratings, good sleepers reported significantly higher HRQoL than poor sleepers. Sleep disturbances were significantly higher and HRQoL significantly lower in self- as compared to parental ratings. Parent-child agreement was higher for subscales measuring observable aspects. Girls experienced significantly stronger sleep disturbances and lower self-rated HRQoL than boys. Discussion: Our findings support the positive relationship of sleep and HRQoL. Furthermore, parents significantly underestimate sleep disturbances and overestimate HRQoL in their children
A Photometric Study of the Young Stellar Population Throughout the lambda Orionis Star-Forming Region
We present VRI photometry of 320,917 stars with 11 < R < 18 throughout the
lambda Orionis star-forming region. We statistically remove the field stars and
identify a representative PMS population throughout the interior of the
molecular ring. The spatial distribution of this population shows a
concentration of PMS stars around lambda Ori and in front of the B35 dark
cloud. Few PMS stars are found outside these pockets of high stellar density,
suggesting that star formation was concentrated in an elongated cloud extending
from B35 through lambda Ori to the B30 cloud. We find a lower limit for the
global stellar mass of about 500 Mo. We find that the global ratio of low- to
high-mass stars is similar to that predicted by the field initial mass
function, but this ratio varies strongly as a function of position in the
star-forming region. Locally, the star-formation process does not produce a
universal initial mass function. We construct a history of the star-forming
complex. This history incorporates a recent supernova to explain the
distribution of stars and gas today.Comment: 42 pages, 11 figures; to appear in the Astronomical Journa
Brorfelde Schmidt CCD Catalog (BSCC)
The Brorfelde Schmidt CCD Catalog (BSCC) contains about 13.7 million stars,
north of +49 deg Declination with precise positions and V, R photometry. The
catalog has been constructed from the reductions of 18,667 CCD frames observed
with the Brorfelde Schmidt Telescope between 2000 and 2007. The Tycho-2 catalog
was used for astrometric and photometric reference stars. Errors of individual
positions are about 20 to 200 mas for stars in the R = 10 to 18 mag range.
External comparisons with 2MASS and SDSS reveal possible small systematic
errors in the BSCC of up to about 30 mas. The catalog is supplemented with J,
H, and K_s magnitudes from the 2MASS catalog. The catalog data file (about 550
MB ASCII, compressed) will be made available at the Strasbourg Data Center
(CDS).Comment: 16 pages, 22 figures, 2 tables, accepted by A
Precision Astrometry of a Sample of Speckle Binaries and Multiples with the Adaptive Optics Facilities at the Hale and Keck II Telescopes
Using the adaptive optics facilities at the 200-in Hale and 10-m Keck II, we
observed in the near infrared a sample of 12 binary and multiple stars and one
open cluster. We used the near diffraction limited images of these systems to
measure the relative separations and position angles between their components.
In this paper, we investigate and correct for the influence of the differential
chromatic refraction and chip distortions on our relative astrometric
measurements. Over one night, we achieve an astrometric precision typically
well below 1 miliarcsecond and occasionally as small as 40 microarcseconds.
Such a precision is in principle sufficient to astrometrically detect planetary
mass objects around the components of nearby binary and multiple stars. Since
we have not had sufficiently large data sets for the observed sample of stars
to detect planets, we provide the limits to planetary mass objects based on the
obtained astrometric precision.Comment: 18 pages, 8 figures, 9 tables, to appear in MNRA
A catalogue of bright (K <9) M dwarfs
Using the Position and Proper Motion Extended-L (PPMXL) catalogue, we have used optical and near-infrared colour cuts together with a reduced proper motion cut to find bright M dwarfs for future exoplanet transit studies. PPMXL's low proper motion uncertainties allow us to probe down to smaller proper motions than previous similar studies. We have combined unique objects found with this method to that of previous work to produce 8479 K <9 M dwarfs. Low-resolution spectroscopy was obtained of a sample of the objects found using this selection method to gain statistics on their spectral type and physical properties. Results show a spectral-type range of K7-M4V. This catalogue is the most complete collection of K <9 M dwarfs currently available and is made available here.Peer reviewe
HN Peg B: A Test of Models of the L to T Dwarf Transition
Luhman and collaborators recently discovered an early-T dwarf companion to
the G0 dwarf star HN Peg, using Spitzer Infrared Array Camera (IRAC) images.
Companionship was established on the basis of the common proper motion inferred
from 1998 Two Micron All Sky Survey images and the 2004 IRAC images. In this
paper we present new near-infrared imaging data which confirms the common
proper motion of the system. We also present new 3 - 4 um spectroscopy of HN
Peg B, which provides tighter constraints on both the bolometric luminosity
determination and the comparison to synthetic spectra. New adaptive optics
imaging data are also presented, which shows the T dwarf to be unresolved,
providing limits on the multiplicity of the object. We use the age, distance
and luminosity of the solar-metallicity T dwarf to determine its effective
temperature and gravity, and compare synthetic spectra with these values, and a
range of grain properties and vertical mixing, to the observed 0.8 - 4.0 um
spectra and mid-infrared photometry. We find that models with temperature and
gravity appropriate for the older end of the age range of the system (0.5 Gyr)
can do a reasonable job of fitting the data, but only if the photospheric
condensate cloud deck is thin, and if there is significant vertical mixing in
the atmosphere. Dwarfs such as HN Peg B, with well-determined metallicity,
radius, gravity and temperature will allow development of dynamical atmosphere
models, leading to the solution of the puzzle of the L to T dwarf transition.Comment: 22 pages including 2 Tables and 5 Figures, accepted for publication
by the Astrophysical Journal, April 8 200
A Catalog of Chandra X-ray Sources in the Carina Nebula
We present a catalog of ~14,000 X-ray sources observed by the ACIS instrument
on the Chandra X-ray Observatory within a 1.42 square degree survey of the
Great Nebula in Carina, known as the Chandra Carina Complex Project (CCCP).
This study appears in a Special Issue of the ApJS devoted to the CCCP. Here, we
describe the data reduction and analysis procedures performed on the X-ray
observations, including calibration and cleaning of the X-ray event data, point
source detection, and source extraction. The catalog appears to be complete
across most of the field to an absorption-corrected total-band luminosity of
~10^{30.7} erg/s for a typical low-mass pre-main sequence star. Counterparts to
the X-ray sources are identified in a variety of visual, near-infrared, and
mid-infrared surveys. The X-ray and infrared source properties presented here
form the basis of many CCCP studies of the young stellar populations in Carina.Comment: Accepted for the ApJS Special Issue on the Chandra Carina Complex
Project (CCCP), scheduled for publication in May 2011. All 16 CCCP Special
Issue papers are available at
http://cochise.astro.psu.edu/Carina_public/special_issue.html through 2011 at
least. 29 pages, 11 figure
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