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Assurance of learning standards and scaling strategies to enable expansion of experiential learning courses in management education
In today’s dynamic globalized business environment, management educators must develop pedagogies that support students to manage and lead in rapidly changing business contexts. An increasing number of institutions use experiential learning as a component of their curriculum to address this challenge. Initially, a response to industry criticism that graduates were unable effectively apply skills needed to be successful, experiential learning has become a baseline expectation in management education programs. Students increasingly expect opportunities to practice and demonstrate competency in the theories they learn in the classroom by applying them in real-world projects. However, expanding such opportunities for students is limited by a unique set of complex administrative challenges inherent in this approach. To expand opportunities for students, institutions must overcome scalability obstacles resulting from the customized nature of the offerings. Business challenges where student teams work with external partners provide a real world learning experience. But they also pose difficulty in applying a standardized approach to assurance of learning. Course content must be redeveloped each time the course is offered, as external projects must be sourced, leading to input and output variation. Advising, monitoring, and assessing students is resource intensive, because at many schools each team is assigned a different business challenge. This article offers a set of assurance of learning standards that institutions can apply to project-based experiential learning courses and posits that greater cross-departmental integration in sourcing projects and better use of technology can increase the efficacy and efficiency of the courses to address the scalability issue.Educatio
X-ray Emission from the 3C 273 Jet
We present results from four recent Chandra monitoring observations of the
jet in 3C 273 using the ACIS detector, obtained between November 2003 and July
2004. We find that the X-ray emission comes in two components: unresolved knots
that are smaller than the corresponding optically emitting knots and a broad
channel that is about the same width as the optical interknot region. We
compute the jet speed under the assumption that the X-ray emission is due to
inverse Compton scattering of the cosmic microwave background, finding that the
dimming of the jet X-ray emission to the jet termination relative to the radio
emission may be due to bulk deceleration.Comment: 2 pages, 2 figures, to appear in the proceedings of "The X-ray
Universe 2005", San Lorenzo de El Escorial (Spain), 26-30 September 200
The radio-ultraviolet spectral energy distribution of the jet in 3C273
We present deep VLA and HST observations of the large-scale jet in 3C 273
matched to 0.3" resolution. The observed spectra show a significant flattening
in the infrared-ultraviolet wavelength range. The jet's emission cannot
therefore be assumed to arise from a single electron population and requires
the presence of an additional emission component. The observed smooth
variations of the spectral indices along the jet imply that the physical
conditions vary correspondingly smoothly. We determine the maximum particle
energy for the optical jet using synchrotron spectral fits. The slow decline of
the maximum energy along the jet implies particle reacceleration acting along
the entire jet. In addition to the already established global anti-correlation
between maximum particle energy and surface brightness, we find a weak positive
correlation between small-scale variations in maximum particle energy and
surface brightness. The origin of these conflicting global and local
correlations is unclear, but they provide tight constraints for reacceleration
models.Comment: 28 pages, lots of figures, accepted for publication in A&
Spectral Decomposition of Broad-Line AGNs and Host Galaxies
Using an eigenspectrum decomposition technique, we separate the host galaxy
from the broad line active galactic nucleus (AGN) in a set of 4666 spectra from
the Sloan Digital Sky Survey (SDSS), from redshifts near zero up to about 0.75.
The decomposition technique uses separate sets of galaxy and quasar
eigenspectra to efficiently and reliably separate the AGN and host
spectroscopic components. The technique accurately reproduces the host galaxy
spectrum, its contributing fraction, and its classification. We show how the
accuracy of the decomposition depends upon S/N, host galaxy fraction, and the
galaxy class. Based on the eigencoefficients, the sample of SDSS broad-line AGN
host galaxies spans a wide range of spectral types, but the distribution
differs significantly from inactive galaxies. In particular, post-starburst
activity appears to be much more common among AGN host galaxies. The
luminosities of the hosts are much higher than expected for normal early-type
galaxies, and their colors become increasingly bluer than early-type galaxies
with increasing host luminosity. Most of the AGNs with detected hosts are
emitting at between 1% and 10% of their estimated Eddington luminosities, but
the sensitivity of the technique usually does not extend to the Eddington
limit. There are mild correlations among the AGN and host galaxy
eigencoefficients, possibly indicating a link between recent star formation and
the onset of AGN activity. The catalog of spectral reconstruction parameters is
available as an electronic table.Comment: 18 pages; accepted for publication in A
Temporal fluctuations in excimer-like interactions between pi-conjugated chromophores
Inter- or intramolecular coupling processes between chromophores such as
excimer formation or H- and J-aggregation are crucial to describing the
photophysics of closely packed films of conjugated polymers. Such coupling is
highly distance dependent, and should be sensitive to both fluctuations in the
spacing between chromophores as well as the actual position on the chromophore
where the exciton localizes. Single-molecule spectroscopy reveals these
intrinsic fluctuations in well-defined bi-chromophoric model systems of
cofacial oligomers. Signatures of interchromophoric interactions in the excited
state - spectral red-shifting and broadening, and a slowing of
photoluminescence decay - correlate with each other but scatter strongly
between single molecules, implying an extraordinary distribution in coupling
strengths. Furthermore, these excimer-like spectral fingerprints vary with
time, revealing intrinsic dynamics in the coupling strength within one single
dimer molecule, which constitutes the starting point for describing a molecular
solid. Such spectral sensitivity to sub-Angstrom molecular dynamics could prove
complementary to conventional FRET-based molecular rulers
A new quality of life consultation template for patients with venous leg ulceration
OBJECTIVE: Chronic venous leg ulcers (CVLUs) are common and recurrent, however, care for patients predominantly has a focus which overlooks the impact of the condition on quality of life. The aim of this study was to develop a simple, evidence-based consultation template, with patients and practitioners, which focuses consultations on quality of life themes. METHOD: A nominal group was undertaken to develop a new consultation template for patients with CVLUs based on the findings of earlier qualitative study phases. RESULTS: A user-friendly two-sided A4 template was designed to focus nurse-patient consultations on the quality of life challenges posed by CVLUs. CONCLUSION: CVLUs impact negatively on the quality of life of the patient but this receives inadequate attention during current consultations. This new template will help to ensure that key concerns are effectively raised, explored and addressed during each consultation. DECLARATION OF INTEREST: The NHS West Midlands Strategic Health Authority funded this study. The authors have no conflicts of interest to declare.NHS West Midlands Health Authorit
Chandra Discovery of 10 New X-Ray Jets Associated With FR II Radio Core-Selected AGNs in the MOJAVE Sample
The Chandra X-ray observatory has proven to be a vital tool for studying
high-energy emission processes in jets associated with Active Galactic Nuclei
(AGN).We have compiled a sample of 27 AGN selected from the radio flux-limited
MOJAVE (Monitoring of Jets in AGN with VLBA Experiments) sample of highly
relativistically beamed jets to look for correlations between X-ray and radio
emission on kiloparsec scales. The sample consists of all MOJAVE quasars which
have over 100 mJy of extended radio emission at 1.4 GHz and a radio structure
of at least 3" in size. Previous Chandra observations have revealed X-ray jets
in 11 of 14 members of the sample, and we have carried out new observations of
the remaining 13 sources. Of the latter, 10 have Xray jets, bringing the
overall detection rate to ~ 78%. Our selection criteria, which is based on
highly compact, relativistically beamed jet emission and large extended radio
flux, thus provides an effective method of discovering new X-ray jets
associated with AGN. The detected X-ray jet morphologies are generally well
correlated with the radio emission, except for those displaying sharp bends in
the radio band. The X-ray emission mechanism for these powerful FR II
(Fanaroff-Riley type II) jets can be interpreted as inverse Compton scattering
off of cosmic microwave background (IC/CMB) photons by the electrons in the
relativistic jets. We derive viewing angles for the jets, assuming a
non-bending, non-decelerating model, by using superluminal parsec scale speeds
along with parameters derived from the inverse Compton X-ray model. We use
these angles to calculate best fit Doppler and bulk Lorentz factors for the
jets, as well as their possible ranges, which leads to extreme values for the
bulk Lorentz factor in some cases. When both the non-bending and
non-decelerating assumptions are relaxed [abridged]Comment: 38 Pages, 4 Figures, 5 Tables, accepted for publication in Ap
Performance of the GLAS Space Lidar Receiver Through Its Seven-Year Space Mission
NASA s Ice, Cloud, and land Elevation Satellite (ICESat) mission [1,2] carrying the Geoscience Laser Altimeter System (GLAS) Instrument, was launched on January 12, 2003. The three lasers on ICESat have made a total of 1.98 billion laser shot measurements of the Earth s surface and atmosphere during its 17 science data collection campaigns over its seven year operating lifetime. ICESat completed its science mission after the last laser stopped operating in October 2009. The spacecraft was de-orbited on August 30, 2010. The GLAS instrument carried 3 diode-pumped Q-switched Nd:YAG lasers, which emitted 6-nsec wide pulses at 1064 and 532 nm at a 40-Hz rate. There are three lidar receiver channels, a 1064 nm surface altimetry channel, a 1064 nm cloud backscattering lidar channel, and a 532 nm cloud and aerosol backscattering lidar channel. The altimetry and cloud backscatter channels used Si avalanche photodiode (APD) operated in analog mode as in the Mars Global Surveyor s Mars Orbital Laser Altimeter [3,4]. GLAS also utilized a number of new technologies and techniques for space lidar, including passively Q-switched diode-pumped Nd:YAG lasers, a 1-m diameter telescope, a temperature tuned etalon optical bandpass filter, Si APD single photon counting detectors, 1 Gsample/sec waveform digitizers, ultra stable clock oscillators, and digital signal processing and detection algorithms [5]. A global position system (GPS) receiver was used to provide the spacecraft position and epoch times. The ICESat mission provided a unique opportunity to monitor the lidar component performance in the space environment over a multi-year time period. We performed a number of engineering tests periodically to monitor the lidar receiver performance, including receiver sensitivity, timing precision, detector dark noise, etc. A series of engineering tests were also performed after the end of the science mission to evaluate the performance of the spare detector, oscillator, waveform digitizer, and GPS receiver. An experiment was conducted which pointed GLAS to Venus to test the receiver sensitivity to star light and to verify GLAS bore sight with respect to the spacecraft coordinate system. These tests provided unique data to assess the degradation and the rate of change of these key lidar components due to space radiation and aging. They also helped to validate new techniques to operate and calibrate future space lidars
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