1,017 research outputs found
Fourteen Years of Education and Public Outreach for the Swift Gamma-ray Burst Explorer Mission
The Sonoma State University (SSU) Education and Public Outreach (E/PO) group
leads the Swift Education and Public Outreach program. For Swift, we have
previously implemented broad efforts that have contributed to NASA's Science
Mission Directorate E/PO portfolio across many outcome areas. Our current focus
is on highly-leveraged and demonstrably successful activities, including the
wide-reaching Astrophysics Educator Ambassador program, and our popular
websites: Epo's Chronicles and the Gamma-ray Burst (GRB) Skymap. We also make
major contributions working collaboratively through the Astrophysics Science
Education and Public Outreach Forum (SEPOF) on activities such as the on-line
educator professional development course NASA's Multiwavelength Universe. Past
activities have included the development of many successful education units
including the GEMS Invisible Universe guide, the Gamma-ray Burst Educator's
guide, and the Newton's Laws Poster set; informal activities including support
for the International Year of Astronomy, the development of a toolkit about
supernovae for the amateur astronomers in the Night Sky Network, and the Swift
paper instrument and glider models.Comment: 7th Huntsville Gamma-Ray Burst Symposium, GRB 2013: paper 42 in eConf
Proceedings C130414
EFTA: CONDEMNED TO LIVE. An analysis of the recent political and economic events in Europe which have contributed to the unexpected longevity of the European Free Trade Association. Some thoughts on it's potential as an alternative to the Common Market. American Universities Field Staff. West Europe Series Vol. IV No. 1, 1969
Using the Big Ideas in Cosmology to Teach College Students
Recent advances in our understanding of the Universe have revolutionized our
view of its structure, composition and evolution. However, these new ideas have
not necessarily been used to improve the teaching of introductory astronomy
students. In this project, we have conducted research into student
understanding of cosmological ideas so as to develop effective web-based tools
to teach basic concepts important to modern cosmology. The tools are intended
for use at the introductory college level. Our research uses several
instruments, including open-ended and multiple choice surveys conducted at
multiple institutions, as well as interviews and course artifacts at one
institution, to ascertain what students know regarding modern cosmological
ideas, what common misunderstandings and misconceptions they entertain, and
what sorts of materials can most effectively overcome student difficulties in
learning this material. These data are being used to create a suite of
interactive, web-based tutorials that address the major ideas in cosmology
using real data. Having students engage with real data is a powerful means to
help students overcome certain misconceptions. Students master the scientific
concepts and reasoning processes that lead to our current understanding of the
universe through interactive tasks, prediction and reflection, experimentation,
and model building.Comment: 2012 Fermi Symposium proceedings - eConf C12102
Ammonia toxicity to the brain
Hyperammonemia can be caused by various acquired or inherited disorders such as urea cycle defects. The brain is much more susceptible to the deleterious effects of ammonium in childhood than in adulthood. Hyperammonemia provokes irreversible damage to the developing central nervous system: cortical atrophy, ventricular enlargement and demyelination lead to cognitive impairment, seizures and cerebral palsy. The mechanisms leading to these severe brain lesions are still not well understood, but recent studies show that ammonium exposure alters several amino acid pathways and neurotransmitter systems, cerebral energy metabolism, nitric oxide synthesis, oxidative stress and signal transduction pathways. All in all, at the cellular level, these are associated with alterations in neuronal differentiation and patterns of cell death. Recent advances in imaging techniques are increasing our understanding of these processes through detailed in vivo longitudinal analysis of neurobiochemical changes associated with hyperammonemia. Further, several potential neuroprotective strategies have been put forward recently, including the use of NMDA receptor antagonists, nitric oxide inhibitors, creatine, acetyl-L-carnitine, CNTF or inhibitors of MAPKs and glutamine synthetase. Magnetic resonance imaging and spectroscopy will ultimately be a powerful tool to measure the effects of these neuroprotective approache
A Direct Detection of Gas Accretion: The Lyman Limit System in 3C 232
The gas added and removed from galaxies over cosmic time greatly affects
their stellar populations and star formation rates. QSO absorption studies in
close QSO/galaxy pairs create a unique opportunity to study the physical
conditions and kinematics of this gas. Here we present new Hubble Space
Telescope (HST) images of the QSO/galaxy pair 3C 232/NGC 3067. The quasar
spectrum contains a Lyman-limit absorption system (LLS) due to NGC 3067 at cz =
1421 km/s that is associated with the nearby SAB galaxy NGC 3067. Previous work
identifies this absorber as a high-velocity cloud (HVC) in NGC 3067 but the
kinematics of the absorbing gas, infalling or outflowing, were uncertain. The
HST images presented here establish the orientation of NGC 3067 and so
establish that the LLS/HVC is infalling. Using this system as a prototype, we
extend these results to higher-z Mg II/LLS to suggest that Mg II/LLSs are a
sight line sampling of the so-called "cold mode accretion" (CMA) infalling onto
luminous galaxies. But to match the observed Mg II absorber statistics, the CMA
must be more highly ionized at higher redshifts. The key observations needed to
further the study of low-z LLSs is HST/UV spectroscopy, for which a new
instrument, the Cosmic Origins Spectrograph, has just been installed greatly
enhancing our observational capabilities.Comment: 9 pages, 5 figures, accepted by PAS
Going … Going … Public? Taking a United States Professional Sports League Public
The four major American professional sports leagues—the MLB, NBA, NHL, and NFL—are wildly popular, but the leagues fail to capitalize fully on their success because they are organized in a largely inefficient manner. By organizing as unincorporated non-profits, leagues forgo their ability to raise capital via investors, forcing taxpayers to bear the burden of league investments such as new stadium construction. Further, the current organizational model creates a collective action problem, as self-interested team owners focus their support on actions that benefit their own franchise and leave ineffective commissioners in power.
A solution to these problems is for a professional sports league to incorporate and organize as a publicly traded company. The application of the corporate model to the sports world is not a new concept—several individual franchises have “gone public” over the years. But, because of concerns arising from the fiduciary duties of care and loyalty, the corporate model is much more viable for an entire league rather than an individual team
The Local Lyman-Alpha Forest: Absorbers in Galaxy Voids
We have conducted pointed redshift surveys for galaxies in the direction of
bright AGN whose HST far-UV spectra contain nearby (cz <~ 30,000 kms), low
column density (12.5 <= log N_{HI} (cm s^{-2}) <= 14.5) Ly-alpha forest
absorption systems. Here we present results for four lines-of-sight which
contain nearby (cz <~ 3000 kms) Ly-alpha absorbers in galaxy voids. Although
our data go quite deep (-13 <= M_{B}(limit) <= -14) out to impact parameters of
100-250 h_{70}^{-1} kpc, these absorbers remain isolated and thus appear to be
truly intergalactic, rather than part of galaxies or their halos. Since we and
others have discovered no galaxies in voids, the only baryons detected in the
voids are in the Ly-alpha ``clouds''. Using a photoionization model for these
clouds, the total baryonic content of the voids is 4.5% +/- 1.5% of the mean
baryon density.Comment: 5 pages, 1 figure, accepted for publication in Astrophysical Journal
Letter
Dark halos acting as chaos controllers in asymmetric triaxial galaxy models
We study the regular or chaotic character of orbits in a 3D dynamical model,
describing a triaxial galaxy surrounded by a spherical dark halo component. Our
numerical experiments suggest that the percentage of chaotic orbits decreases
exponentially as the mass of the dark halo increases. A linear increase of the
percentage of the chaotic orbits was observed as the scale length of the halo
component increases. In order to distinguish between regular and chaotic
motion, we chose to use the total angular momentum Ltot of the 3D orbits as a
new indicator. Comparison with other, previously used, dynamical indicators,
such as the Lyapunov Characteristic Exponent or the P(f) spectral method, shows
that the Ltot indicator gives very fast and reliable results for characterizing
the nature of orbits in galactic dynamical models.Comment: Published in Research in Astronomy and Astrophysics (RAA) journa
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