23,452 research outputs found
Extravehicular tunnel suit system Patent
Design and development of flexible tunnel for use by spacecrews in performing extravehicular activitie
Detections and Constraints on White Dwarf Variability from Time-Series GALEX Observations
We search for photometric variability in more than 23,000 known and candidate
white dwarfs, the largest ultraviolet survey compiled for a single study of
white dwarfs. We use gPhoton, a publicly available calibration/reduction
pipeline, to generate time-series photometry of white dwarfs observed by GALEX.
By implementing a system of weighted metrics, we select sources with
variability due to pulsations and eclipses. Although GALEX observations have
short baselines (< 30 min), we identify intrinsic variability in sources as
faint as Gaia G = 20 mag. With our ranking algorithm, we identify 49 new
variable white dwarfs (WDs) in archival GALEX observations. We detect 41 new
pulsators: 37 have hydrogen-dominated atmospheres (DAVs), including one
possible massive DAV, and four are helium-dominated pulsators (DBVs). We also
detect eight new eclipsing systems; five are new discoveries, and three were
previously known spectroscopic binaries. We perform synthetic injections of the
light curve of WD 1145+017, a system with known transiting debris, to test our
ability to recover similar systems. We find that the 3{\sigma} maximum
occurrence rate of WD 1145+017-like transiting objects is < 0.5%.Comment: 17 pages, 13 figure
Exceptional covers and bijections on rational points
We show that if f: X --> Y is a finite, separable morphism of smooth curves
defined over a finite field F_q, where q is larger than an explicit constant
depending only on the degree of f and the genus of X, then f maps X(F_q)
surjectively onto Y(F_q) if and only if f maps X(F_q) injectively into Y(F_q).
Surprisingly, the bounds on q for these two implications have different orders
of magnitude. The main tools used in our proof are the Chebotarev density
theorem for covers of curves over finite fields, the Castelnuovo genus
inequality, and ideas from Galois theory.Comment: 19 pages; various minor changes to previous version. To appear in
International Mathematics Research Notice
The effects of label design characteristics on perceptions of genetically modified food
Objective. To explore the effects on perceptions of labelling food for genetically modified content. Background: there is increasing public pressure for the compulsory labelling of genetically modified food content on all food products, and yet little is known about how the design and content of such food labels will influence product perceptions. The current research draws upon warning label research - a field in which the effect of label design manipulations on perceptions of, and responses to, potential or perceived risks is well documented. Method. Two experiments are reported that investigate how label design features influence the perception of genetically modified foods. The effects of label colour (red, blue and green), wording style (definitive vs. probabilistic and explicit vs. non-explicit) and information source (government agency, consumer group and manufacturer) on hazard perceptions and purchase intentions were measured. Results. Hazard perceptions and purchase intentions were both influenced by label design characteristics in predictable ways. Any reference to genetic modification, even if the label is stating that the product is free of genetically modified ingredients, increased hazard perception, and decreased purchase intentions, relative to a no-label condition. Conclusion. Label design effects generalise from warning label research to influence the perception of genetically modified foods in predictable ways. Application. The design of genetically modified food labels. Ā© 2012 Copyright Taylor and Francis Group, LLC
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