98 research outputs found
Near infrared spectroscopy of the type IIn SN 2010jl: evidence for high velocity ejecta
The Type IIn supernova SN 2010jl was relatively nearby and luminous, allowing
detailed studies of the near-infrared (NIR) emission. We present 1 - 2.4 micron
spectroscopy over the age range of 36 - 565 days from the earliest detection of
the supernova. On day 36, the H lines show an unresolved narrow emission
component along with a symmetric broad component that can be modeled as the
result of electron scattering by a thermal distribution of electrons. Over the
next hundreds of days, the broad components of the H lines shift to the blue by
700 km/s, as is also observed in optical lines. The narrow lines do not show a
shift, indicating they originate in a different region. He I 1.0830 and 2.0587
micron lines both show an asymmetric broad emission component, with a shoulder
on the blue side that varies in prominence and velocity from -5500 km/s on day
108 to -4000 km/s on day 219. This component may be associated with the higher
velocity flow indicated by X-ray observations of the supernova. The absence of
the feature in the H lines suggests that this is from a He rich ejecta flow.
The He I 1.0830 micron feature has a narrow P Cygni line, with absorption
extending to ~100 km/s and strengthening over the first 200 days, and an
emission component which weakens with time. At day 403, the continuum emission
becomes dominated by a blackbody spectrum with a temperature of ~1900 K,
suggestive of dust emission.Comment: 17 pages, 18 figure
The Future of Textiles: Disruption and Collaboration
The textile field, while not “local” in the geographic sense, is a community: a group of people with a shared language, history, and practices that date back thousands of years. As deeply-rooted as those materials and practices are, textiles is also an area that has historically experienced enormous disruptions due to changing technology and globalization. In the 21st century, we are undergoing something like a second Industrial Revolution. Advances in digital and robotic technologies and shifting labor markets are driving a revolution in where and how things are made. Global climate change, lack of food security for much of the world’s population, and concern about overwhelming quantities of waste and toxic pollution are altering our priorities for land and resource management. These challenges are bringing together the formerly opposed approaches of handcraft and high-tech, organic and artificial in new and unexpected ways. Venturing into the field of textiles today is taking a bold step into a constellation of disciplines that, on the surface, may not appear to have much in common with the history of cloth. But the future of textiles will rely on cross-collaborations in areas of science, medicine, engineering, technology, agriculture, waste management, and other specialties, as well as an understanding of the balance required for environmentally and economically sustainable textile production. The panel will discuss the changes that are taking place in the textile field and will present new and burgeoning areas in the textile industry including commercially viable smart textiles, non-petroleum synthesized fibers, waterless dyeing, alternative manufacturing strategies, and sustainable practices. It will celebrate positive disruptions and cross-disciplinary collaborations that will enlarge and enrich the textile community, and demonstrate once again the resiliency of its social fabric
Performance of Three LED-Based Fluorescence Microscopy Systems for Detection of Tuberculosis in Uganda
BACKGROUND: Direct smear microscopy using Ziehl-Neelsen (ZN) staining is the mainstay of tuberculosis (TB) diagnosis in most high burden countries, but is limited by low sensitivity in routine practice, particularly in high human immunodeficiency virus (HIV) prevalence settings. METHODS: We compared the performance of three commercial light emitting diode (LED)-based microscopy systems (Primostar™ iLED, Lumin™ and AFTER®) for fluorescent detection of Mycobacterium tuberculosis with ZN microscopy on slides prepared from sputum of TB suspects. Examination time for LED-based fluorescent microscopy (LED FM) and ZN slides was also compared, and a qualitative user appraisal of the LED FM systems was carried out. RESULTS: LED FM was between 5.6 and 9.4% more sensitive than ZN microscopy, although the difference was not statistically significant. There was no significant difference in the sensitivity or specificity of the three LED FM systems, although the specificity of Fraen AFTER was somewhat lower than the other LED FM methods. Examination time for LED FM was 2 and 4 times less than for ZN microscopy. LED FM was highly acceptable to Ugandan technologists, although differences in operational performance of the three systems were reported. CONCLUSIONS: LED FM compares favourably with ZN microscopy, with equivalent specificity and a modest increase in sensitivity. Screening of slides was substantially quicker using LED FM than ZN, and LED FM was rated highly by laboratory technologists. Available commercial systems have different operational characteristics which should be considered prior to programmatic implementation
Determinants of social media adoption by B2B organizations
This study contributes to the current dearth of knowledge on the potential of social media as a marketing tool in industrial settings, by focusing on factors that determine social media adoption by B2B organizations. A conceptual model, which draws on the technology acceptance model and resource-based theory, is developed and tested using quantitative data from B2B organizations in the UK. Findings suggest that perceived usefulness of social media within B2B organizational contexts is determined by image, perceived ease of use and perceived barriers. Additionally, the results show that adoption of social media is significantly affected by organizational innovativeness and perceived usefulness. The moderating role of organizational innovativeness is also tested but no support is found. The findings of the study are further validated via nine qualitative interviews with B2B senior managers, yielding additional interesting and in-depth insights into the drivers of social media adoption by B2B organizations
SDSS-III: Massive Spectroscopic Surveys of the Distant Universe, the Milky Way Galaxy, and Extra-Solar Planetary Systems
Building on the legacy of the Sloan Digital Sky Survey (SDSS-I and II),
SDSS-III is a program of four spectroscopic surveys on three scientific themes:
dark energy and cosmological parameters, the history and structure of the Milky
Way, and the population of giant planets around other stars. In keeping with
SDSS tradition, SDSS-III will provide regular public releases of all its data,
beginning with SDSS DR8 (which occurred in Jan 2011). This paper presents an
overview of the four SDSS-III surveys. BOSS will measure redshifts of 1.5
million massive galaxies and Lya forest spectra of 150,000 quasars, using the
BAO feature of large scale structure to obtain percent-level determinations of
the distance scale and Hubble expansion rate at z<0.7 and at z~2.5. SEGUE-2,
which is now completed, measured medium-resolution (R=1800) optical spectra of
118,000 stars in a variety of target categories, probing chemical evolution,
stellar kinematics and substructure, and the mass profile of the dark matter
halo from the solar neighborhood to distances of 100 kpc. APOGEE will obtain
high-resolution (R~30,000), high signal-to-noise (S/N>100 per resolution
element), H-band (1.51-1.70 micron) spectra of 10^5 evolved, late-type stars,
measuring separate abundances for ~15 elements per star and creating the first
high-precision spectroscopic survey of all Galactic stellar populations (bulge,
bar, disks, halo) with a uniform set of stellar tracers and spectral
diagnostics. MARVELS will monitor radial velocities of more than 8000 FGK stars
with the sensitivity and cadence (10-40 m/s, ~24 visits per star) needed to
detect giant planets with periods up to two years, providing an unprecedented
data set for understanding the formation and dynamical evolution of giant
planet systems. (Abridged)Comment: Revised to version published in The Astronomical Journa
Reflections on the Study of Transformational Leadership
Streaming audio requires RealPlayer.The University Archives has determined that this item is of continuing value to OSU's history.Ohio State University. Mershon Center for International Security StudiesStreaming audio, phot
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WHAT MADE BERKELEY GREAT? The Sources of Berkeley's Sustained Academic Excellence
UC Berkeley’s chief academic officer explores the historical sources of Berkeley’s academic excellence. He identifies five key factors: (1) wealth from many sources; (2) supportive and skilled governors; (3) leadership from key UC presidents; (4) the pioneering ethos within the State of California; and (5) a process of continuous devolution of authority within the State and the University. He then addresses the extent to which these factors continue as causal drivers today. He concludes by identifying optimistic and pessimistic scenarios, based on contrasting assumptions about the strength of those causal drivers, and ends with a call for the State and the UC system not to inhibit efforts by UCB’s leaders to do what is needed to sustain Berkeley’s academic excellence
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