466 research outputs found
Academic freedom and changing focus on student assessment in Dutch higher education
The paper addresses this issue of academic freedom by exploring how the new regulation regarding student assessment procedures has been implemented in Dutch higher education institutions. We endeavour to understand how teaching staff have responded to the new rules and to what extent decision-making processes have included teaching staff. To answer our research question, we would like to concentrate on two issues: the role of the Examination Board and the design of the assessment procedures. Our working hypothesis is that new institutional arrangements of student assessments reduce academic freedom. Previous research has showed that academics largely engage in symbolic compliance with the imperatives of management requirements while keeping their academic freedom intact (Leisyte and Dee 2012). Universities in their turn, are increasingly acting as strategic actors in not only complying but also shaping their institutional environments (Meyer and Rowan 1977, Greenwood and Hinnings 1996, KrĂŒcken 2011). The responses to established norms and beliefs range from passivity to increasingly active resistance (Oliver 1991). We will discuss if the impingement on academic freedom is offset by increased assurance of quality for students, and explore how to balance the two values of freedom and quality. Methods used are document analysis and interviews with teachers, university administrators and during Fall 2011 in the frame of the Identifying Barriers in promoting European Standards and Guidelines for Quality Assurance (IBAR) project
Correlation of CAG repeat length between the maternal and paternal allele of the Huntingtin gene: evidence for assortative mating
Triplet repeats contribute to normal variation in behavioral traits and when expanded, cause brain disorders. While Huntington's Disease is known to be caused by a CAG triplet repeat in the gene Huntingtin, the effect of CAG repeats on brain function below disease threshold has not been studied. The current study shows a significant correlation between the CAG repeat length of the maternal and paternal allele in the Huntingtin gene among healthy subjects, suggesting assortative mating
Observation of the spin-orbit gap in bilayer graphene by one-dimensional ballistic transport
We report on measurements of quantized conductance in gate-defined quantum
point contacts in bilayer graphene that allow the observation of subband
splittings due to spin-orbit coupling. The size of this splitting can be tuned
from 40 to 80 eV by the displacement field. We assign this gate-tunable
subband-splitting to a gap induced by spin-orbit coupling of Kane-Mele type,
enhanced by proximity effects due to the substrate. We show that this
spin-orbit coupling gives rise to a complex pattern in low perpendicular
magnetic fields, increasing the Zeeman splitting in one valley and suppressing
it in the other one. In addition, we observe the existence of a spin-polarized
channel of 6 e/h at high in-plane magnetic field and of signatures of
interaction effects at the crossings of spin-split subbands of opposite spins
at finite magnetic field.Comment: 5 pages, 4 figures, Supplement 6 figure
Dielectric screening of the Kohn anomaly of graphene on hexagonal boron nitride
Kohn anomalies in three-dimensional metallic crystals are dips in the phonon dispersion that are caused by abrupt changes in the screening of the ion cores by the surrounding electron gas. These anomalies are also present at the high-symmetry points Î and K in the phonon dispersion of two-dimensional graphene, where the phonon wave vector connects two points on the Fermi surface. The linear slope around the kinks in the highest optical branch is proportional to the electron-phonon coupling. Here, we present a combined theoretical and experimental study of the influence of the dielectric substrate on the vibrational properties of graphene. We show that screening by the dielectric substrate reduces the electron-phonon coupling at the high-symmetry point K and leads to an upshift of the Raman 2D line. This results in the observation of a Kohn anomaly that can be tuned by screening. The exact position of the 2D line can thus be taken also as a signature for changes in the (electron-phonon limited) conductivity of graphene
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