1,877 research outputs found
Coping strategies for staff involved in assessment of laboratory write-ups
Laboratory-based practical exercises, which are an important and time-consuming part of many science degree courses, may be directed towards a variety of learning objectives. Some of these have traditionally been assessed by staff marking the student's written account of the laboratory experiment (the laboratory write-up) but increasing student numbers, which may have doubled or quadrupled on some modules, have made it difficult to sustain this approach. In addition, there is evidence that the formative element of the assessment (i.e. the comments written by staff on the laboratory write-up) is not fully utilized by students who are often only interested in the mark given. This paper reports on experience with the various strategies which may be used to cope with the increased marking load while maintaining or improving the learning gain from the formative element of the assessment. The adoption of a balanced mixture of strategies may present the best solution to the problem but must be tailored to local circumstances
The Findings of an Assessment Audit: an NTFS Project Report
An Assessment Audit is described consisting of 47 questions, each being scored 0 to 4, by the module team depending on the extent to which the audit point was satisfied. Scores of 2 or less indicated unsatisfactory provision. Audits were carried out on 14 bioscience- or medicine- based modules in 13 universities.
There was great variability between modules in the hours spent by:
• teachers in direct contact with students (12 to 914);
• teachers involved in the process of assessment (2 to 372);
• students actually being assessed (2 to 60 hours per student);
• students in the teaching and learning process (35 to 300).
The highest scoring module obtained 133 out of 188 (71%) with 11 out of 47 items scored at 2 or less while the lowest scoring module obtained 47% with 27 items scoring 2 or less. Features consistently poorly addressed were:
• consideration of learning objectives/assessment in other modules taken by the student;
• consideration of consistency among multiple markers;
• use of known mark sets to validate data processing;
• availability of exemplar answers;
• feedback on end-of-module assessments.
A common issue concerns the isolation of modules and module teams. This suggests the need for a strengthening of the course thread and emphasis on the totality of the student learning experience rather than the individual module. The audit provides a framework within which course teams can reflect on and improve the quality of the assessment in their module
Seamless Online Distribution of Amundsen Multibeam Data
Since 2003, all underway multibeam and sub-bottom data from the Canadian Coast Guard Ship Amundsen has been posted online within approximately six months of the end of each cruise. A custom interface allowing the user to access 15\u27 latitude by 30\u27 longitude mapsheets was implemented in 2006, allowing the user to download the bathymetric and backscatter data at 10 metre resolution. While this interface matched the underlying data management scheme implemented at the University of New Brunswick, the zoom and pan capability was at a fixed scale with limited contextual data. In the past few years, with the introduction of web-based geographic information systems (GIS) (e.g. Google Maps, Yahoo Maps, Bing Maps), there have been thousands of maps published online. These online GIS programs are a suitable platform to display the seven years of Amundsen coverage within the context of the GIS-served satellite imagery and allow the user to freely browse all data in a familiar interface. The challenge, however, for serving up third party data through these map engines is to efficiently cope with the multiple zoom levels and changing resolutions. Custom tiling software was developed to take all the raw data from the seven years of Amundsen (and others\u27) multibeam coverage and convert it into multiple scale resolution images suitable for interpretation by Google Maps. The images were stored in a pyramid structure utilizing Google\u27s map projection and uniquely named to reflect their georeferencing and resolution. This image pyramid is then accessed by Google Maps according to the user\u27s current zoom level to optimize visualization. This multi-resolution data is served up on demand from the University of New Brunswick for dynamic overlay on Google\u27s satellite data. This web interface allows any interested parties to easily view multibeam and sub-bottom data from the Pacific Ocean through the Canadian Arctic Archipelago and into the Atlantic Ocean. The broad overview helps to understand regional trends and then focus on areas of interest at high resolutions to see particular features. The web interface also provides a link to the 15\u27 by 30\u27 mapsheet model with full source traceability
Changes in use of technological methods of teaching and learning in undergraduate pharmacology in UK higher education
A survey of methods of teaching and learning used in pharmacology in UK Higher Education was conducted in 1996 (Markham et al. 1998). A further survey involving 342 UK pharmacologists has now (2001) been conducted, and with respect to 1996, the findings were as follows:
a. there has been a large drop (78% to 33%) in the utilisation of chalk and talk lectures and there is high use of PowerPoint presentations (60%);
b. there has been a large increase in the more than occasional utilisation (23% to 62%) of CAL materials;
c. utilisation of video material has increased markedly (13% to 28%);
d. there has been a small increase in the utilisation of problem based learning;
e. self- and peer assessment by students is not used extensively and use is little changed since 1996;
f. there has been a small improvement in the encouragement/support/recognition provided by institutions for teaching; and
g. the adequacy of IT hardware/support/resources for teaching has improved from 1996 when resources were viewed as inadequate.
Teaching staff have increased use of technology-based teaching and are now much more positive about its availability and use. This may reflect the operation of a variety of programs, aimed at increasing technology-based teaching, operating during the period
Probing the Relation Between X-ray-Derived and Weak-Lensing-Derived Masses for Shear-Selected Galaxy Clusters: I. A781
We compare X-ray and weak-lensing masses for four galaxy clusters that
comprise the top-ranked shear-selected cluster system in the Deep Lens Survey.
The weak-lensing observations of this system, which is associated with A781,
are from the Kitt Peak Mayall 4-m telescope, and the X-ray observations are
from both Chandra and XMM-Newton. For a faithful comparison of masses, we adopt
the same matter density profile for each method, which we choose to be an NFW
profile. Since neither the X-ray nor weak-lensing data are deep enough to well
constrain both the NFW scale radius and central density, we estimate the scale
radius using a fitting function for the concentration derived from cosmological
hydrodynamic simulations and an X-ray estimate of the mass assuming
isothermality. We keep this scale radius in common for both X-ray and
weak-lensing profiles, and fit for the central density, which scales linearly
with mass. We find that for three of these clusters, there is agreement between
X-ray and weak-lensing NFW central densities, and thus masses. For the other
cluster, the X-ray central density is higher than that from weak-lensing by 2
sigma. X-ray images suggest that this cluster may be undergoing a merger with a
smaller cluster. This work serves as an additional step towards understanding
the possible biases in X-ray and weak-lensing cluster mass estimation methods.
Such understanding is vital to efforts to constrain cosmology using X-ray or
weak-lensing cluster surveys to trace the growth of structure over cosmic time.Comment: 14 pages, 7 figures, matches version in Ap
Submillimeter Continuum Properties of Cold Dust in the Inner Disk and Outflows of M82
Deep submillimeter (submm) continuum imaging observations of the starburst
galaxy M82 are presented at 350, 450, 750 and 850 micron wavelengths, that were
undertaken with the Submillimetre Common-User Bolometer Array (SCUBA) on the
James Clerk Maxwell Telescope in Hawaii. The presented maps include a
co-addition of submm data mined from the SCUBA Data Archive. The co-added data
produce the deepest submm continuum maps yet of M82, in which low-level 850
micron continuum has been detected out to 1.5kpc, at least 10% farther in
radius than any previously published submm detections of this galaxy. The
overall submm morphology and spatial spectral energy distribution of M82 have a
general north-south asymmetry consistent with H-alpha and X-ray winds,
supporting the association of the extended continuum with outflows of dust
grains from the disk into the halo. The new data raise interesting points about
the origin and structure of the submm emission in the inner disk of M82. In
particular, SCUBA short wavelength evidence of submm continuum peaks that are
asymmetrically distributed along the galactic disk suggests the inner-disk
emission is re-radiation from dust concentrations along a bar (or perhaps a
spiral) rather than edges of a dust torus, as is commonly assumed. Higher
resolution submm interferometery data from the Smithsonian Submillimeter Array
and later Atacama Large Millimeter Array should spatially resolve and further
constrain the reported dust emission structures in M82.Comment: Accepted by the Astronomical Journal -- 28 pages and 14 figure
Neurophysiological signatures of Alzheimer's disease and frontotemporal lobar degeneration : pathology versus phenotype
The disruption of brain networks is characteristic of neurodegenerative dementias. However, it is controversial whether changes in connectivity reflect only the functional anatomy of disease, with selective vulnerability of brain networks, or the specific neurophysiological consequences of different neuropathologies within brain networks. We proposed that the oscillatory dynamics of cortical circuits reflect the tuning of local neural interactions, such that different pathologies are selective in their impact on the frequency spectrum of oscillations, whereas clinical syndromes reflect the anatomical distribution of pathology and physiological change. To test this hypothesis, we used magnetoencephalography from five patient groups, representing dissociated pathological subtypes and distributions across frontal, parietal and temporal lobes: amnestic Alzheimer's disease, posterior cortical atrophy, and three syndromes associated with frontotemporal lobar degeneration. We measured effective connectivity with graph theory-based measures of local efficiency, using partial directed coherence between sensors. As expected, each disease caused large-scale changes of neurophysiological brain networks, with reductions in local efficiency compared to controls. Critically however, the frequency range of altered connectivity was consistent across clinical syndromes that shared a likely underlying pathology, whilst the localization of changes differed between clinical syndromes. Multivariate pattern analysis of the frequency-specific topographies of local efficiency separated the disorders from each other and from controls (accuracy 62% to 100%, according to the groups' differences in likely pathology and clinical syndrome). The data indicate that magnetoencephalography has the potential to reveal specific changes in neurophysiology resulting from neurodegenerative disease. Our findings confirm that while clinical syndromes have characteristic anatomical patterns of abnormal connectivity that may be identified with other methods like structural brain imaging, the different mechanisms of neurodegeneration also cause characteristic spectral signatures of physiological coupling that are not accessible with structural imaging nor confounded by the neurovascular signalling of functional MRI. We suggest that these spectral characteristics of altered connectivity are the result of differential disruption of neuronal microstructure and synaptic physiology by Alzheimer's disease versus frontotemporal lobar degeneration.Peer reviewe
Effect of N2, Ne and Ar seeding on Alcator C-Mod H-mode confinement
The mitigation of divertor heat fluxes is an active topic of investigation on existing tokamaks. One approach uses radiation, both inside and outside the last closed flux surface (LCFS), to convert plasma thermal energy, usually directed towards dedicated plasma facing components, to soft X-ray and ultraviolet radiation, spread over a much larger surface area. Recent enhanced D-α H-mode experiments on Alcator C-Mod varied the ICRF input power and radiative power losses via impurity seeding to demonstrate that normalized energy confinement depends strongly on the difference between input power and the radiated power inside the LCFS. These investigations also show that when seeded with either Ne or N2, a factor of two and higher reduction in outer divertor heat flux is achieved while maintaining H[subscript 98,y2] ∼ 1.0. Conversely, when seeding with Ar, confinement is limited to H[subscript 98,y2] ∼ 0.8 for a similar level of exhaust power.United States. Dept. of Energy (DOE Contract Number DEFC0299ER54512
Punctured polygons and polyominoes on the square lattice
We use the finite lattice method to count the number of punctured staircase
and self-avoiding polygons with up to three holes on the square lattice. New or
radically extended series have been derived for both the perimeter and area
generating functions. We show that the critical point is unchanged by a finite
number of punctures, and that the critical exponent increases by a fixed amount
for each puncture. The increase is 1.5 per puncture when enumerating by
perimeter and 1.0 when enumerating by area. A refined estimate of the
connective constant for polygons by area is given. A similar set of results is
obtained for finitely punctured polyominoes. The exponent increase is proved to
be 1.0 per puncture for polyominoes.Comment: 36 pages, 11 figure
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