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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
Short-type PB-cadherin promotes survival of gonocytes and activates JAK-STAT signalling
AbstractNeonatal development of the rat testis involves a number of critical events including re-entry of gonocytes into the cell cycle and eventual loss of many of these cells and their progeny via apoptosis. Since surviving gonocytes give rise to subsequent generations of germ cells, regulation of their fate is critical for adult testicular function. Here, we have identified a role for short-type PB-cadherin (STPB-C) in promoting survival of gonocytes in neonatal rats and we have linked its expression to the JAK-STAT signaling pathway. These findings were obtained with varied approaches including use of transgenic rats overexpressing STPB-C which were studied with protein microarrays and other techniques, direct examination of germ cell apoptosis and survival in gonocyte–Sertoli cell co-cultures, and direct study of the JAK-STAT pathway in these models and in L cells transfected with STPB-C. These data provide new information on the regulation of gonocyte fate and exciting new evidence supporting a link between the JAK-STAT pathway and cadherin-based cell–cell interactions
Orthopedic management of the extremities in patients with Morquio A syndrome.
BackgroundMusculoskeletal involvement in Morquio A syndrome (mucopolysaccharidosis IVA; MPS IVA) contributes significantly to morbidity and mortality. While the spinal manifestations of the disorder have received considerable attention in the literature, there have been few reported studies to date to guide the management of the orthopedic problems associated with the lower and upper extremities.PurposeThe objective was to develop recommendations for the management of the extremities in patients with Morquio A syndrome.MethodsA group of specialists in orthopedics, pediatrics and genetics with experience in the management of Morquio A patients convened to review and discuss current clinical practices and to develop preliminary recommendations. Evidence from the literature was retrieved. Recommendations were further refined until consensus was reached.Results and conclusionsThis present article provides a detailed review and discussion of the lower and upper extremity deformities in Morquio A syndrome and presents recommendations for the assessment and treatment of these complications. Key issues, including the importance of early diagnosis and the implications of medical therapy, are also addressed. The recommendations herein represent an attempt to develop a uniform and practical approach to managing patients with Morquio A syndrome and improving their outcomes
An Investigation of Three Approaches to Vocabulary Learning in High School Spanish Classes
Three vocabulary learning approaches -- rote memorization; Cover, Copy, Compare (CCC); and Cover, Copy, Compare Adapted with picture (CCCA) – were examined for effectiveness in promoting long-term memory retention for productive vocabulary in foreign language learning. Pretest, posttest, and delayed posttest data were collected using Conjuguemos, an on-line Spanish program. Results indicated a significant increase in mean scores with each assessment for all treatments; however, there was no significant difference in recall among the three learning approaches. Students were also surveyed about their preferences in approaches. Although survey responses indicated a preference for CCC, most students reported abandoning use of this method after six months
A simple test for the existence of two accretion modes in Active Galactic Nuclei
By analogy to the different accretion states observed in black-hole X-ray
binaries (BHXBs), it appears plausible that accretion disks in active galactic
nuclei (AGN) undergo a state transition between a radiatively efficient and
inefficient accretion flow. If the radiative efficiency changes at some
critical accretion rate, there will be a change in the distribution of black
hole masses and bolometric luminosities at the corresponding transition
luminosity. To test this prediction, I consider the joint distribution of AGN
black hole masses and bolometric luminosities for a sample taken from the
literature. The small number of objects with low Eddington-scaled accretion
rates mdot < 0.01 and black hole masses Mbh < 10^9 Msun constitutes tentative
evidence for the existence of such a transition in AGN. Selection effects, in
particular those associated with flux-limited samples, systematically exclude
objects in particular regions of the black hole mass-luminosity plane.
Therefore, they require particular attention in the analysis of distributions
of black hole mass, bolometric luminosity, and derived quantities like the
accretion rate. I suggest further observational tests of the BHXB-AGN
unification scheme which are based on the jet domination of the energy output
of BHXBs in the hard state, and on the possible equivalence of BHXB in the very
high (or "steep power-law") state showing ejections and efficiently accreting
quasars and radio galaxies with powerful radio jets.Comment: Accepted by ApJ; 14 pages, 4 figures, uses emulateap
Particle acceleration in rotating and shearing jets from AGN
We model the acceleration of energetic particles due to shear and centrifugal
effects in rotating astrophysical jets. The appropriate equation describing the
diffusive transport of energetic particles in a collisionless, rotating
background flow is derived and analytical steady state solutions are discussed.
In particular, by considering velocity profiles from rigid, over flat to
Keplerian rotation, the effects of centrifugal and shear acceleration of
particles scattered by magnetic inhomogeneities are distinguished. In the case
where shear acceleration dominates, it is confirmed that power law particle
momentum solutions exist, if the mean scattering
time is an increasing function of momentum. We show
that for a more complex interplay between shear and centrifugal acceleration,
the recovered power law momentum spectra might be significantly steeper but
flatten with increasing azimuthal velocity due to the increasing centrifugal
effects. The possible relevance of shear and centrifugal acceleration for the
observed extended emission in AGN is demonstrated for the case of the jet in
the quasar 3C273.Comment: 15 pages (including 8 pages Appendix), 4 figures; accepted for
publication in A&
High Energy Radiation Generated at Boundary Shear Layers of Relativistic Jets
A simple model of cosmic ray electron acceleration at the jet boundary
(Ostrowski 2000) yields a power-law particle energy distribution of
ultrarelativistic electrons with an energy cut-off growing with time and
finally, a growing particle bump at the energy, where energy gains equal
radiation losses. For such electron distribution, in tens-of-kpc scale jets, we
derived the observed time varying spectra of synchrotron and inverse-Compton
radiation, including comptonization of synchrotron and cosmic microwave
background photons. Slowly varying spectral index along the jet in the
`low-frequency' spectral range is a natural consequence of boundary layer
acceleration. Variations of the high energy bump of the electron distribution
can give rise to anomalous behaviour in X-ray band in comparison to the lower
frequencies.Comment: 7 pages, 1 figure included, accepted for publication by PASA Volume
19, Number 1: Special Issue on AGN Variability Across the Electromagnetic
Spectru
Observation Of Light Diffusion And Correlation Transport In Nematic Liquid Crystals
Light diffusion and temporal correlation transport are studied in an orientationally ordered multiply scattering medium. In particular, we experimentally demonstrate the anisotropic diffusion of light through a turbid nematic liquid crystal, and we measure the temporal correlations of these diffused speckle fields for the first time. The measurements are shown to provide useful information about this material, specifically the average rotational viscosity of the director. Computer simulations corroborate both the experimental observations and a more rigorous analytic theoretical formulation of this problem
Polarimetry and the High-Energy Emission Mechanisms in Quasar Jets
The emission mechanisms in extragalactic jets include synchrotron and various
inverse-Compton processes. At low (radio through infrared) energies, it is
widely agreed that synchrotron emission dominates in both low-power (FR I) and
high-power (FR II and quasar) jets, because of the power-law nature of the
spectra observed and high polarizations. However, at higher energies, the
emission mechanism for high-power jets at kpc scales is hotly debated. Two
mechanisms have been proposed: either inverse-Compton of cosmic microwave
background photons or synchrotron emission from a second, high-energy
population of electrons. Here we discuss optical polarimetry as a method for
diagnosing the mechanism for the high-energy emission in quasar jets, as well
as revealing the jet's three-dimensional energetic and magnetic field
structure. We then discuss high-energy emission mechanisms for powerful jets in
the light of the HST polarimetry of PKS 1136-135.Comment: 4 pages, 1 figure. To appear in proceedings of "The Monster's Fiery
Breath: Feedback in galaxies, groups, and clusters" meeting, June 1-5, 2009
held in Madison, WI, US
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