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Project report: Evaluation of two post-graduate pre-registration nursing modules âFinding the Blendâ: An evaluation of the balance between online and face to face learning and teaching in a blended curriculum
In the School of Health Sciences we have adopted a blended learning approach for the delivery of the current nursing curriculum. It is intended to enhance and extend the learning opportunities for students.
This approach makes full use of available learning technologies whilst recognising the value of face to face interaction and facilitation. It fosters supportive and collaborative learning networks amongst students and encourages deep learning by engaging students in incremental learning tasks and, student directed learning. It also enables students to self- pace their learning.
As our nursing programme is being implemented we have engaged both academics and students in a systematic and iterative evaluation of the blended aspects of the programme.
Our aims were to:
a) Investigate how students experience the current balance between their classroom and online activities
b) Evaluate the effectiveness of the range of activities, both online and face to face
c) Identify points of good practice based on project evaluation and available literature.
In this paper we share the results of our evaluation and highlight key messages for further development and improvement of designing the âblendâ. Our recommendations may be beneficial for design teams who may need to engage in similar projects in the future
The Evolution of the Stellar Hosts of Radio Galaxies
We present new near-infrared images of z>0.8 radio galaxies from the
flux-limited 7C-III sample of radio sources for which we have recently obtained
almost complete spectroscopic redshifts. The 7C objects have radio luminosities
about 20 times fainter than 3C radio galaxies at a given redshift. The absolute
magnitudes of the underlying host galaxies and their scale sizes are only
weakly dependent on radio luminosity. Radio galaxy hosts at z~2 are
significantly brighter than the hosts of radio-quiet quasars at similar
redshifts and the model AGN hosts of Kauffmann & Haehnelt (2000). There is no
evidence for strong evolution in scale size, which shows a large scatter at all
redshifts. The hosts brighten significantly with redshift, consistent with the
passive evolution of a stellar population that formed at z>~3. This scenario is
consistent with studies of host galaxy morphology and submillimeter continuum
emission, both of which show strong evolution at z>~2.5. The lack of a strong
``redshift cutoff'' in the radio luminosity function to z>4 suggests that the
formation epoch of the radio galaxy host population lasts >~1Gyr from z>~5 to
z~3. We suggest these facts are best explained by models in which the most
massive galaxies and their associated AGN form early due to high baryon
densities in the centres of their dark matter haloes.Comment: To appear in A
A submillimetre survey of the star-formation history of radio galaxies
We present the results of the first major systematic submillimetre survey of
radio galaxies spanning the redshift range 1 < z < 5. The primary aim of this
work is to elucidate the star-formation history of this sub-class of elliptical
galaxies by tracing the cosmological evolution of dust mass. Using SCUBA on the
JCMT we have obtained 850-micron photometry of 47 radio galaxies to a
consistent rms depth of 1 mJy, and have detected dust emission in 14 cases. The
radio galaxy targets have been selected from a series of low-frequency radio
surveys of increasing depth (3CRR, 6CE, etc), in order to allow us to separate
the effects of increasing redshift and increasing radio power on submillimetre
luminosity. Although the dynamic range of our study is inevitably small, we
find clear evidence that the typical submillimetre luminosity (and hence dust
mass) of a powerful radio galaxy is a strongly increasing function of redshift;
the detection rate rises from 15 per cent at z 2.5,
and the average submillimetre luminosity rises as (1+z)^3 out to z~4. Moreover
our extensive sample allows us to argue that this behaviour is not driven by
underlying correlations with other radio galaxy properties such as radio power,
radio spectral index, or radio source size/age. Although radio selection may
introduce other more subtle biases, the redshift distribution of our detected
objects is in fact consistent with the most recent estimates of the redshift
distribution of comparably bright submillimetre sources discovered in blank
field surveys. The evolution of submillimetre luminosity found here for radio
galaxies may thus be representative of massive ellipticals in general.Comment: 31 pages - 10 figures in main text, 3 pages of figures in appendix.
This revised version has been re-structured, but the analysis and conclusions
have not changed. Accepted for publication in MNRA
HST and UKIRT imaging observations of z ~ 1 6C radio galaxies - I. The data
The results of Hubble Space Telescope and UKIRT imaging observations are
presented for a sample of 11 6C radio galaxies with redshifts 0.85 < z < 1.5.
The observations of the 6C sources reveal a variety of different features,
similar to those observed around the higher luminosity of the aligned emission
appears less extreme in the case of the 6C radio galaxies. For both samples,
the aligned emission clearly cannot be explained by a single emission
mechanism; line emission and related nebular continuum emission, however, often
provide a significant contribution to the aligned emission.Comment: 17 pages, 11 figures (figs 3,6,11 low resolution - full resolution
images can be obtained from http://www.mrao.cam.ac.uk/~kji/ImagingFigs/).
Accepted for publication in MNRA
Deep spectroscopy of z~1 6C radio galaxies - II. Breaking the redshift-radio power degeneracy
The results of a spectroscopic analysis of 3CR and 6C radio galaxies at
redshift z~1 are contrasted with the properties of lower redshift radio
galaxies, chosen to be matched in radio luminosity to the 6C sources studied at
z~1, thus enabling the P-z degeneracy to be broken. Partial rank correlations
and principal component analysis have been used to determine which of z and P
are the critical parameters underlying the observed variation of the ionization
state andd kinematics of the emission line gas. [OII]/H-beta is shown to be a
useful ionization mechanism diagnostic. Statistical analysis of the data shows
that the ionization state of the emission line gas is strongly correlated with
radio power, once the effects of other parameters are removed. No dependence of
ionization state on z is observed, implying that the ionization state of the
emission line gas is solely a function of the AGN properties rather than the
hostt galaxy and/or environment. Statistical analysis of the kinematic
properties of the emission line gas shows that these are strongly correlated
independently withh both P and z. The correlation with redshift is the stronger
of the two, suggesting that host galaxy composition or environment may play a
role in producing the less extreme gas kinematics observed in the emission line
regions of low redshift galaxies. For both the ionization and kinematic
properties of thee galaxies, the independent correlations observed with radio
size are strongest. Radio source age is a determining factor for the extended
emission line regions.Comment: 10 pages, 5 figures, accepted for publication in MNRA
MEROPS: the database of proteolytic enzymes, their substrates and inhibitors
Peptidases, their substrates and inhibitors are of great relevance to biology, medicine and biotechnology. The MEROPS database (http://merops.sanger.ac.uk) aims to fulfil the need for an integrated source of information about these. The database has hierarchical classifications in which homologous sets of peptidases and protein inhibitors are grouped into protein species, which are grouped into families, which are in turn grouped into clans. The database has been expanded to include proteolytic enzymes other than peptidases. Special identifiers for peptidases from a variety of model organisms have been established so that orthologues can be detected in other species. A table of predicted active-site residue and metal ligand positions and the residue ranges of the peptidase domains in orthologues has been added to each peptidase summary. New displays of tertiary structures, which can be rotated or have the surfaces displayed, have been added to the structure pages. New indexes for gene names and peptidase substrates have been made available. Among the enhancements to existing features are the inclusion of small-molecule inhibitors in the tables of peptidaseâinhibitor interactions, a table of known cleavage sites for each protein substrate, and tables showing the substrate-binding preferences of peptidases derived from combinatorial peptide substrate libraries
The importance of radio sources in accounting for the highest mass black holes
The most massive black holes lie in the most massive elliptical galaxies, and
at low-z all radio-loud AGNs lie in giant ellipticals. This strongly suggests a
link between radio-loudness and black hole mass. We argue that the increase in
the radio-loud fraction with AGN luminosity in optically-selected quasar
samples is consistent with this picture. We also use the ratio of black holes
today to quasars at z~2 to conclude that the most bolometrically-luminous AGN,
either radio-loud or radio quiet, are constrained to have lifetimes <~10^8 yr.
If radio sources are associated with black holes of >~10^9 M_sun at all
redshifts, then the same lifetime constraint applies to all radio sources with
luminosities above L_5GHz ~ 10^24 W/Hz/sr.Comment: 6 pages, 2 figures. To appear in "Lifecycles of Radio Galaxies", ed
J. Biretta et al., New Astronomy Review
On Star Formation and the Non-Existence of Dark Galaxies
We investigate whether a baryonic dark galaxy or `galaxy without stars' could
persist indefinitely in the local universe, while remaining stable against star
formation. To this end, a simple model has been constructed to determine the
equilibrium distribution and composition of a gaseous protogalactic disk.
Specifically, we determine the amount of gas that will transit to a Toomre
unstable cold phase via the H2 cooling channel in the presence of a UV--X-ray
cosmic background radiation field.
All but one of the models are predicted to become unstable to star formation.
Moreover, we find that all our model objects would be detectable via HI line
emission, even in the case that star formation is potentially avoided. These
results are consistent with the non-detection of isolated extragalactic HI
clouds with no optical counterpart (galaxies without stars) by HIPASS.
Additionally, where star formation is predicted to occur, we determine the
minimum interstellar radiation field required to restore gravothermal
stability, which we then relate to a minimum global star formation rate. This
leads to the prediction of a previously undocumented relation between HI mass
and star formation rate that is observed for a wide variety of dwarf galaxies
in the HI mass range 10^8--10^10 M_sun. The existence of such a relation
strongly supports the notion that the well observed population of dwarf
galaxies represent the minimum rates of self-regulating star formation in the
universe. (Barely abridged)Comment: 19 pages, 8 figures, TeX using emulateapj.cls, v2 accepted for
publication in ApJ (16/8/5) with one figure deleted and a number of minor
clarifying revision
Molecular Clouds as Ensembles of Transient Cores
We construct models of molecular clouds that are considered as ensembles of
transient cores. Each core is assumed to develop in the background gas of the
cloud, grow to high density and decay into the background. The chemistry in
each core responds to the dynamical state of the gas and to the gas-dust
interaction. Ices are deposited on the dust grains in the core's dense phase,
and this material is returned to the gas as the core expands to low density.
The cores of the ensemble number typically one thousand and are placed randomly
in position within the cloud, and are assigned a random evolutionary phase.
The models are used to generate molecular line contour maps of a typical dark
cloud. These maps are found to represent extremely well the characteristic
features of observed maps of the dark cloud L673, which has been observed at
both low and high resolutions. The computed maps are found to exhibit the
general morphology of the observed maps, and to generate similar sizes of
emitting regions, molecular column densities, and the separations between peaks
of emissions of various molecular species. The models give insight into the
nature of molecular clouds and the dynamical processes occurring within them,
and significantly constrain dynamical and chemical processes in the
interstellar medium.Comment: 29 pages, 8 figures. Accepted for publication in Ap
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