915 research outputs found
Collaboration in the Midst of Change: Growing Librarian-Archivist Partnerships for Engaging New Students and Faculty
Collaboration between librarians and archivists is a valuable way to share expertise and effort when instructing first-year English students on research skills they will need to succeed in college. It is also vital to orienting new faculty to library and archive resources for their scholarship and teaching, as well as encouraging students to value the library and archives resources and knowledge. The unique first-year English program at the Georgia Institute of Technology (Georgia Tech) provides a constantly renewing pool of both new students and faculty members. This article identifies common themes in library and archive instruction and key elements of engaging first-year faculty and their students in becoming long-term patrons, in the midst of Georgia Tech’s Library Next initiative, a re-imagining of the twenty-first century library and a major renovation of physical spaces
A Period and a Prediction for the Of?p Spectrum Alternator HD 191612
The observational picture of the enigmatic O-type spectrum variable HD191612
has been sharpened substantially. A symmetrical, low-amplitude light curve with
a period near 540 d has recently been reported from Hipparcos photometry. This
period satisfies all of the spectroscopy since at least 1982, including
extensive new observations during 2003 and 2004, and it has predicted the next
transition during September--October 2004. Measurements of the H alpha
equivalent width reveal a sharp emission peak in the phase diagram, in contrast
to the apparently sinusoidal light curve. The He II absorption-line strength is
essentially constant, while He I varies strongly, possibly filled in by
emission in the O6 state, thus producing the apparent spectral-type variations.
The O8 state appears to be the "normal" one. Two intermediate O7 observations
have been obtained, which fall at the expected phases, but these are the only
modern observations of the transitions so far. The period is too long for
rotation or pulsation; although there is no direct evidence as yet for a
companion, a model in which tidally induced oscillations drive an enhanced wind
near periastron of an eccentric orbit appears promising. Further observations
during the now predictable transitions may provide a critical test. Ultraviolet
and X-ray observations during both states will likely also prove illuminating.Comment: 7 pages, 3 figures, 1 table; scheduled for the 2004 December 10 issue
of ApJL, Vol. 617, No. 1. ApJ
High dispersion spectroscopy of two A supergiant systems in the Small Magellanic Cloud with novel properties
We present the results of a spectroscopic investigation of two novel variable
bright blue stars in the SMC, OGLE004336.91-732637.7 (SMC-SC3) and the
periodically occulted star OGLE004633.76-731204.3 (SMC-SC4), whose photometric
properties were reported by Mennickent et al. (2010). High-resolution spectra
in the optical and far-UV show that both objects are actually A + B type
binaries. Three spectra of SMC-SC4 show radial velocity variations, consistent
with the photometric period of 184.26 days found in Mennickent et al. 2010. The
optical spectra of the metallic lines in both systems show combined absorption
and emission components that imply that they are formed in a flattened
envelope. A comparison of the radial velocity variations in SMC-SC4 and the
separation of the V and R emission components in the Halpha emission profile
indicate that this envelope, and probably also the envelope around SMC-SC3, is
a circumbinary disk with a characteristic orbital radius some three times the
radius of the binary system. The optical spectra of SMC-SC3 and SMC-SC4 show,
respectively, HeI emission lines and discrete Blue Absorption Components (BACs)
in metallic lines. The high excitations of the HeI lines in the SMC-SC3
spectrum and the complicated variations of FeII emission and absorption
components with orbital phase in the spectrum of SMC-SC4 suggests that shocks
occur between the winds and various static regions of the stars' co-rotating
binary-disk complexes. We suggest that BACs arise from wind shocks from the A
star impacting the circumbinary disk and a stream of former wind-efflux from
the B star accreting onto the A star. We dub these objects prototype of a small
group of Magellanic Cloud wind-interacting A + B binaries.Comment: To be published in MNRA
Update on leukodystrophies and developing trials
Leukodystrophies are a heterogeneous group of rare genetic disorders primarily affecting the white matter of the central nervous system. These conditions can present a diagnostic challenge, requiring a comprehensive approach that combines clinical evaluation, neuroimaging, metabolic testing, and genetic testing. While MRI is the main tool for diagnosis, advances in molecular diagnostics, particularly whole-exome sequencing, have significantly improved the diagnostic yield. Timely and accurate diagnosis is crucial to guide symptomatic treatment and assess eligibility to participate in clinical trials. Despite no specific cure being available for most leukodystrophies, gene therapy is emerging as a potential treatment avenue, rapidly advancing the therapeutic prospects in leukodystrophies. This review will explore diagnostic and therapeutic strategies for leukodystrophies, with particular emphasis on new trials
A Motivational Perspective on the Personalization of Gamification
The gamification of information systems has seen success in a variety of contexts. However, research has shown that the degree to which gamification is successful varies between individuals. The current paper evaluates the effectiveness of personalized gamification in a warehouse management context. Additionally, this paper explores why personalized gamification can be more successful than non-personalized gamification. Twenty-six subjects participated in a within-subject laboratory experiment in which goal setting and feedback game elements were integrated into a wearable management information system to examine their effect on user performance in a warehouse picking task. The effectiveness of personalized gamification was evaluated by categorizing participants into user types using the HEXAD model and examining performance across conditions and user types. Results show that user type significantly affects the relationship between game elements and user performance. This paper takes a step forward in exploring the motivational mechanisms that explain the efficacy of personalized gamification
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