400 results on '"Gunn, K."'
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2. X-ray spectra of sources in the 13H XMM-Newton / Chandra deep field
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Page, M. J., Loaring, N. S., Dwelly, T., Mason, K. O., McHardy, I., Gunn, K., Moss, D., Sasseen, T., Cordova, F., Kennea, J., and Seymour, N.
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Astrophysics - Abstract
We present the X-ray spectra of 86 optically-identified sources in the 13H XMM-Newton/Chandra deep field which have >70 X-ray counts. The sample consists of 50 broad line AGN, 25 narrow emission line galaxies, 6 absorption line galaxies, and 5 Galactic stars. The majority (42/50) of the broad line AGN have X-ray spectra which are consistent with a power law shape. They have a mean photon index of Gamma = 2.0 +- 0.1 and an intrinsic dispersion sigma = 0.4 +- 0.1. Five BLAGN show a deficit of soft X-rays, indicating absorption. Significant absorption is more common in the narrow emission line galaxies (13/25) and absorption line galaxies (2/6) than in the broad line AGN (5/50), but is not universal in any of these classes of object. The majority of the 20 absorbed sources have X-ray spectra consistent with a simple cold photoelectric absorber, but 6/20 require more complex models with either an additional component of soft X-ray emitting plasma, or an ionised absorber. Of the 16 galaxies which do not show evidence for X-ray absorption, only 2 objects are likely to be powered by star formation, and both have 2-10 keV X-ray luminosities of <= 10^40 cgs. The X-ray emission in the other 14 unabsorbed NELGs and galaxies is most likely powered by AGN, which are not detected in the optical because they are outshone by their luminous host galaxies. The Galactic stars show multi-temperature thermal spectra which peak between 0.5 and 1 keV. Star/AGN discrimination is possible for 4 of the 5 stars solely from their X-ray spectra., Comment: Accepted for publication in MNRAS
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- 2006
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3. XMM-Newton 13H Deep field - I. X-ray sources
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Loaring, N. S., Dwelly, T., Page, M. J., Mason, K., McHardy, I., Gunn, K., Moss, D., Seymour, N., Newsam, A. M., Takata, T., Sekguchi, K., Sasseen, T., and Cordova, F.
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Astrophysics - Abstract
We present the results of a deep X-ray survey conducted with XMM-Newton, centred on the UK ROSAT 13H deep field area. This region covers 0.18 deg^2 and is the first of two areas covered with XMM-Newton as part of an extensive multi-wavelength survey designed to study the nature and evolution of the faint X-ray source population. We have produced detailed Monte-Carlo simulations to obtain a quantitative characterisation of the source detection procedure and to assess the reliability of the resultant sourcelist. We use the simulations to establish a likelihood threshold above which we expect less than 7 (3%) of our sources to be spurious. We present the final catalogue of 225 sources. Within the central 9 arcmin, 68 per cent of source positions are accurate to 2 arcsec, making optical follow-up relatively straightforward. We construct the N(>S) relation in four energy bands: 0.2-0.5 keV, 0.5-2 keV, 2-5 keV and 5-10 keV. In all but our highest energy band we find that the source counts can be represented by a double powerlaw with a bright end slope consistent with the Euclidean case and a break around 10^-14 cgs. Below this flux the counts exhibit a flattening. Our source counts reach densities of 700, 1300, 900 and 300 deg^-2 at fluxes of 4.1x10^-16, 4.5x10^-16, 1.1x10^-15 and 5.3x10^-15 cgs in the 0.2-0.5, 0.5-2, 2-5 and 5-10 keV energy bands respectively. We have compared our source counts with those in the two Chandra deep fields and Lockman hole and find our source counts to be amongst the highest of these fields in all energy bands. We resolve >51% (>50%) of the X-ray background emission in the 1-2 keV (2-5 keV) energy bands., Comment: 27 pages, 18 figures, MNRAS accepted
- Published
- 2005
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4. Constraints on the distribution of absorption in the X-ray selected AGN population found in the 13H XMM-Newton/Chandra deep field
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Dwelly, T., Page, M. J., Loaring, N. S., Mason, K. O., McHardy, I., Gunn, K., and Sasseen, T.
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Astrophysics - Abstract
We present an analysis of the X-ray properties of sources detected in the 13H XMM-Newton deep (200ks) field. In order to constrain the absorbed AGN population, we use extensive Monte Carlo simulations to directly compare the X-ray colours of observed sources with those predicted by several model distributions. We have tested the simplest form of the AGN unified scheme, whereby the intrinsic XLF of absorbed AGN is set to be the same as that of their unabsorbed brethren, coupled with various model distributions of absorption. The best fitting of these models sets the fraction of AGN with absorbing column NH, proportional to (logNH)^8. We have also tested two extensions to the unified scheme: an evolving absorption scenario, and a luminosity dependent model distribution. Both of these provide poorer matches to the observed X-ray colour distributions than the best fitting simple unified model. We find that a luminosity dependent density evolution XLF reproduces poorly the 0.5-2 keV source counts seen in the 13H field. Field to field variations could be the cause of this disparity. Computing the simulated X-ray colours with a simple absorbed power-law + reflection spectral model is found to over-predict, by a factor of two, the fraction of hard sources that are completely absorbed below 0.5 keV, implying that an additional source of soft-band flux must be present for a number of the absorbed sources. Finally, we show that around 40% of the 13H sample are expected to be AGN with NH>10^22 cm^-2., Comment: 13 pages, 9 figures, Accepted for publication in MNRAS
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- 2005
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5. MCG-6-30-15: Long Timescale X-Ray Variability, Black Hole Mass and AGN High States
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McHardy, I M, Gunn, K F, Uttley, P, and Goad, M R
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Astrophysics - Abstract
We present a detailed study of the long-timescale X-ray variability of the Narrow Line Seyfert 1 (NLS1) Galaxy MCG-6-30-15, based on 8 years of frequent observations with the Rossi X-ray Timing Explorer. Combined with short timescale XMM-Newton observations, we derive the powerspectral density (PSD) covering 6 decades from ~10^{-8} to ~10^{-2} Hz. As with NGC4051, another NLS1, the PSD of MCG-6-30-15 is a close analogue of the PSD of a Galactic Black Hole X-ray binary system (GBH) in a `high' rather than a `low' state. Like high state GBHs, its PSD is better fitted by a smoothly bending rather than sharply breaking powerlaw model and the break frequency is 7.6^{+10}_{-3} x 10^{-5} Hz. Assuming linear scaling of break frequency with mass, we estimate the black hole (BH) mass in MCG-6-30-15 to be ~2.9^{+1.8}_{-1.6} X 10^{6} solar masses. We also derive the BH mass using a variety of new optical observations and find a value between 3.6 and 6 x 10^{6} solar masses, consistent with the mass derived from the PSD. Combining these data with revised reverberation masses for other AGN we update the BH mass/break timescale diagram. The observations are consistent with NLS1s having shorter break timescales, for a given mass, than broad line AGN, probably reflecting a higher accretion rate. However the data are also consistent with all of the X-ray bright AGN being high state objects. This result may simply be a selection effect, based on their selection from X-ray all sky catalogues, and their consequent typically high X-ray/radio ratios, which indicate high state systems., Comment: 13 pages, 14 figures. Accepted for publication in Mon. Not. R. astron. Soc
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- 2005
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6. Radio Observations of the 13hr XMM/ROSAT Deep X-ray Survey Area
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Seymour, N., McHardy, I. M., and Gunn, K. F.
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Astrophysics - Abstract
In order to determine the relationship between the faint X-ray and faint radio source populations, and hence to help understand the X-ray and radio emission mechanisms in those faint source populations, we have made a deep 1.4GHz Very Large Array radio survey of the 13h +38deg XMM/ROSAT X-ray Survey Area. From a combined data set of 10hours B configuration data and 14hours A configuration data, maps with 3.35'' resolution and a noise limit of 7.5uJy were constructed. A complete sample of 449 sources was detected within a 30' diameter region above a 4sigma detection limit of 30uJy, at the map centre, making this one of the deepest radio surveys at this frequency. The differential source count shows a significant upturn at sub-milliJansky flux densities, similar to that seen in other deep surveys at 1.4GHz (eg the Phoenix survey), but larger than that seen in the HDF which may have been selected to be under-dense. This upturn is well modelled by the emergence of a population of medium redshift starforming galaxies which dominate at faint flux densities. The brighter source counts are well modelled by AGNs., Comment: 13 pages, 5 figures (one only available from http://www2.iap.fr/users/seymour/ due to size), 2 tables, accepted for publication in MNRAS
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- 2004
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7. Consistency between the radio and MIR faint source counts using the radio-MIR correlation
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Seymour, N., McHardy, I. M., and Gunn, K.
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Astrophysics - Abstract
We show from the recent extrapolation of the radio-FIR correlation to the MIR that the 20 cm and 15 um differential source counts are likely to come from the same parent population., Comment: 2 pages, 2 figures, to appear in proceedings of 'Multi-wavelength AGN surveys', Cozumel, 2003
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- 2004
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8. A medium deep Chandra and Subaru survey of the 13hr XMM/ROSAT deep survey area
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McHardy, I. M., Gunn, K. F., Newsam, A. M., Mason, K. O., Page, M. J., Takata, T., Sekiguchi, K., Sasseen, T., Cordova, F., Jones, L. R., and Loaring, N.
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Astrophysics - Abstract
We present the results of a Chandra ACIS-I survey of a high latitude region at 13h +38 which was earlier observed with ROSAT (McHardy et al. 1998) and which has recently been observed by XMM-Newton for 200ksec. XMM-Newton will provide good quality X-ray spectra for over 200 sources with fluxes around the knee of the logN/logS, which are responsible for the bulk of the X-ray background (XRB). The main aim of the Chandra observations is to provide arcsecond, or better, positions, and hence reliable identifications, for the XMM-Newton sources. The ACIS-I observations were arranged in a mosaic of four 30ksec pointings, covering almost all of the 15' radius XMM-Newton/ROSAT field. We detect 214 Chandra sources above 5 sigma significance, to a limiting flux of \~1.3e-15 erg/cm2/s (0.5-7 keV). Optical counterparts are derived from a Subaru SuprimeCam image reaching to R~27. The very large majority of the Chandra sources have an optical counterpart, with the distribution peaking at 23
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- 2003
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9. X-ray and optical properties of X-ray sources in the 13hr XMM-Newton/Chandra deep survey
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Page, M. J., McHardy, I. M., Gunn, K. F., Loaring, N. S., Mason, K. O., Sasseen, T., Newsam, A., Ware, A., Kennea, J., Sekiguchi, K., and Takata, T.
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Astrophysics - Abstract
The 13hr XMM-Newton/Chandra deep survey is the first of two extremely deep XMM-Newton fields observed by the XMM-OM consortium. A 120 ks Chandra mosaic, covering 0.2 square degrees, provides sensitive, confusion-free point source detection with sub-arcsecond positions, while the 200 ks XMM-Newton observation provides high quality X-ray spectroscopy over the same sky area. We have optical spectroscopic identifications for 70 X-ray sources. Of these, 42 are broad emission-line AGN with a wide range of redshifts. The optical counterparts of a further 23 sources are narrow emission line galaxies and absorption line galaxies. These 23 sources all lie at z < 1 and typically have lower X-ray luminosities than the broad-line AGN. About half of them show significant X-ray absorption and are almost certainly intrinsically absorbed AGN. However some of them have unabsorbed, AGN-like, power-law components in their X-ray spectra, but do not show broad emission lines in their optical spectra. These sources may be weak, unobscured AGN in bright galaxies and their existence at low redshifts could be a consequence of the strong cosmological evolution of AGN characteristic luminosities., Comment: Proceedings of the "X-ray surveys, in the light of the new observatories" workshop, Astronomische Nachrichten, in press (4 pages, 4 figures)
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- 2002
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10. Radio observations of the XMM-Newton/Chandra 13hr deep survey field
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Gunn, K. F., McHardy, I. M., Seymour, N., Newsam, A. M., Page, M. J., Mason, K. O., Loaring, N., Jones, L. R., Muxlow, T., Takata, T., Sekiguchi, K., and Sasseen, T.
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Astrophysics - Abstract
Our VLA observations of the XMM-Newton/Chandra 13hr deep survey field (see Page et al., this proceedings) result in one of the two deepest 1.4GHz radio maps ever made. Within the 15' radius field covered by the deep X-ray data (0.19 sq deg), a total of 556 radio sources are detected, down to a 4 sigma flux limit of 28uJy. Of the 214 Chandra sources, 55 have radio counterparts. The sub-arcsecond accuracy of the VLA and Chandra positions enable us to determine with high confidence the sources common to both surveys. Here we present the relationship between the X-ray and radio source populations at the faintest radio flux limits yet probed by such a study. We discuss how the X-ray/radio relationship differs as a function of optical morphology, ie between unresolved `stellar' objects and well resolved galaxies. We then discuss the origin of the X-ray and radio emission, ie AGN, starburst or a mixture of both, in these two classes of object., Comment: Astronomische Nachrichten, in press (Feb 2003). Proceedings of "X-ray Surveys, in the Light of New Observatories", 4-6 September, Santander, Spain
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- 2002
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11. Soft X-ray properties of a high redshift sample of QSOs observed with ROSAT
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Dewangan, G. C., Singh, K. P., Gunn, K. F., Newsam, A. M., McHardy, I. M., and Jones, L. R.
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Astrophysics - Abstract
In order to study systematically the soft X-ray emission of Active Galactic Nuclei (AGNs) at medium to high redshifts, we have analyzed ROSAT PSPC and HRI data of QSOs at 0.26
3.0), one of which is a narrow-line QSO - a high luminosity version of narrow-line Seyfert 1 galaxies. The average photon index ( ) is 2.40+/-0.09 (with a dispersion of 0.57) in the 0.1-2 keV band. The average QSO spectra in four redshift bins flatten from an average photon index of ~ 2.53 at 0.25 < z < 1 to ~ 2 at 2 < z < 3.4. The flattening of the average photon index can be understood in terms of the redshift effect of the mean intrinsic QSO spectrum consisting of two components - a soft X-ray excess and a power-law component. We have also studied optical spectra of 12 of the 22 QSOs., Comment: 22 pages, uses mn2e.cls, To appear in MNRAS - Published
- 2002
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12. GRB 011121: A Massive Star Progenitor
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Price, P. A., Berger, E., Reichart, D. E., Kulkarni, S. R., Subrahmanyan, R., Wark, R. M., Wieringa, M. H., Frail, D. A., Bailey, J., Boyle, B., Corbett, E., Gunn, K., Ryder, S. D., Seymour, N., Koviak, K., McCarthy, P., Phillips, M., Axelrod, T. S., Bloom, J. S., Djorgovski, S. G., Fox, D. W., Galama, T. J., Harrison, F. A., Hurley, K., Sari, R., Schmidt, B. P., Yost, S. A., Brown, M. J. I., Cline, T., Frontera, F., Guidorzi, C., and Montanari, E.
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Astrophysics - Abstract
Of the cosmological gamma-ray bursts, GRB 011121 has the lowest redshift, z=0.36. More importantly, the multi-color excess in the afterglow detected in the Hubble Space Telescope (HST) light curves is compelling observational evidence for an underlying supernova. Here we present near-infrared and radio observations of the afterglow. We undertake a comprehensive modeling of these observations and those reported in the literature and find good evidence favoring a wind-fed circumburst medium. In detail, we infer the progenitor had a mass loss rate of Mdot ~ 10^-7 / v_w3 Mo/yr where v_w3 is the speed of the wind from the progenitor in units of 10^3 km/s. This mass loss rate is similar to that inferred for the progenitor of SN 1998bw which has been associated with GRB 980425. Our data, taken in conjunction with the HST results of Bloom et al. (2002), provide a consistent picture: the long duration GRB 011121 had a massive star progenitor which exploded as a supernova at about the same time as the GRB event., Comment: 17 pages, 3 figures. Submitted to ApJ Letters
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- 2002
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13. An Outbreak of Escherichia coli O157 Gastroenteritis in a Care Home for the Elderly
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Afza, M., Hawker, J., Thurston, H., Gunn, K., and Orendi, J.
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- 2006
14. Starburst activity in a ROSAT Narrow Emission-Line Galaxy
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Gunn, K. F., McHardy, I. M., Almaini, O., Shanks, T., Sumner, T. J., Muxlow, T. W. B., Efstathiou, A., Jones, L. R., Croom, S. M., Manners, J. C., Newsam, A. M., Mason, K. O., Serjeant, S. B. G., and Rowan-Robinson, M.
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Astrophysics - Abstract
We present multiwaveband photometric and optical spectropolarimetric observations of the R=15.9 narrow emission line galaxy R117_A which lies on the edge of the error circle of the ROSAT X-ray source R117 (from McHardy et al 1998). The overall spectral energy distribution of the galaxy is well modelled by a combination of a normal spiral galaxy and a moderate-strength burst of star formation. The far infra-red and radio emission is extended along the major axis of the galaxy, indicating an extended starburst. On positional grounds, the galaxy is a good candidate for the identification of R117 and the observed X-ray flux is very close to what would be expected from a starburst of the observed far infra-red and radio fluxes. Although an obscured high redshift QSO cannot be entirely ruled out as contributing some fraction of the X-ray flux, we find no candidates to K=20.8 within the X-ray errorbox and so conclude that R117_A is responsible for a large fraction, if not all, of the X-ray emission from R117. Searches for indicators of an obscured AGN in R117_A have so far proven negative; deep spectropolarimetric observations show no signs of broad lines to a limit of one per cent and, for the observed far infra-red and radio emission, we would expect a ten times greater X-ray flux if the overall emission were powered by an AGN. We therefore conclude that the X-ray emission from R117 is dominated by starburst emission from the galaxy R117_A., Comment: 8 pages, 9 figures, MNRAS accepted
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- 2000
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15. Yeast-Derived Sigma C Protein-Induced Immunity against Avian Reovirus
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Wu, H., Williams, Y., Gunn, K. S., Singh, N. K., Locy, R. D., and Giambrone, J. J.
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- 2005
16. X-ray variability in a deep, flux limited sample of QSOs
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Almaini, O., Lawrence, A., Shanks, T., Edge, A., Boyle, B. J., Georgantopoulos, I., Gunn, K. F., Stewart, G. C., and Griffiths, R. E.
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Astrophysics - Abstract
We present an analysis of X-ray variability in a flux limited sample of QSOs. Selected from our deep ROSAT survey, these QSOs span a wide range in redshift ($0.1
0.5$) do not show the anti-correlation with luminosity seen in local AGN. We speculate on the implications of these results for physical models of AGN and their evolution. Finally, we find evidence for X-ray variability in an object classified as a narrow emission-line galaxy, suggesting the presence of an AGN., Comment: Accepted for publication in MNRAS. 11 pages, 12 encapsulated figures. Final proof version, with corrections to Equation A5, Figure 10 and references. Also available at http://www.roe.ac.uk/~omar/astro.html - Published
- 1999
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17. Implications of an Obscured AGN Model for the X-ray Background at Sub-mm and Far Infra-Red Wavelengths
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Gunn, K. F. and Shanks, T.
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Astrophysics - Abstract
Models invoking large populations of obscured AGN are known to provide good fits to the spectrum of the X-ray background and the observed soft and hard X-ray number counts. An important consequence of these models is that significant quantities of dust are required in order to provide the obscuring medium, which will be heated by the nuclear radiation from the AGN, and will radiate in the thermal infra-red. We therefore model the properties of the dust, and predict the contribution of obscured AGN to the intensity of the far infra-red background and the sub-mm source counts and redshift distribution, in order to ascertain whether our models are constrained further by the data available at these wavelengths. Our conservative models predict a contribution of between 5 and 15 per cent of the far infra-red background intensity, whereas if we use more extreme values for several parameters, this value may reach 33 per cent. This suggests that AGN may only form a significant minority of sub-mm sources, in agreement with the results of spectroscopic follow-up. Our models thus show that there is no inconsistency between obscured AGN models for the X-ray background and either sub-mm source counts or the intensity of the far infra-red background. We further propose that obscured AGN may explain the sub-mm emission associated with Extremely Red Objects (EROs). Finally, we make predictions for the redshift distribution of AGN sources detected in faint sub-mm surveys, which should allow future tests of this obscured AGN model., Comment: 13 pages, 16 figures, uses astrobib.sty. Submitted to MNRAS
- Published
- 1999
18. Immunization of Chickens with VP2 Protein of Infectious Bursal Disease Virus Expressed in Arabidopsis thaliana
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Wu, H., Singh, Narendra K., Locy, Robert D., Scissum-Gunn, K., and Giambrone, Joseph J.
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- 2004
19. Distributed optimal control and congestion management in the universal smart energy framework.
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D. Bao Nguyen, Jacquelien M. A. Scherpen, Frits Bliek, Wouter Kramer, and Gunn K. H. Larsen
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- 2016
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20. ASCA observations of deep ROSAT fields IV.IR and hard X-ray observations of an obscured high-redshift QSO
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Georgantopoulos, I., Almaini, O., Shanks, T., Stewart, G. C., Griffiths, R. E., Boyle, B. J., and Gunn, K. F.
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Astrophysics - Abstract
We use UKIRT and ASCA observations to determine the nature of a high redshift (z=2.35) narrow-line AGN, previously discovered by Almaini et al. (1995). The UKIRT observations show a broad Halpha line while no Hbeta line is detected. This together with the red colour (B-K=5.4) suggest that our object is a moderately obscured QSO (Av>3), in optical wavelengths. The ASCA data suggest a hard spectrum, probably due to a large obscuring column, with a photon index of 1.93 (+0.62, -0.46), NH~10^23. The combined ASCA and ROSAT data again suggest a heavily obscured spectrum (NH~10^23 or Av~100). In this picture, the ROSAT soft X-ray emission may arise from electron scattering, in a similar fashion to local Seyfert 1.9. Then, there is a large discrepancy between the moderate reddening witnessed by the IR and the large X-ray absorbing column. This could be possibly explained on the basis of e.g. high gas metallicities or assuming that the X-ray absorbing column is inside the dust sublimation radius. An alternative explanation can be obtained when we allow for variability between the ROSAT and ASCA observations. Then the best fit spectrum is still flat, 1.35 (+0.16, -0.14), but with low intrinsic absorption in better agreement with the IR data, while the ROSAT normalization is a factor of two below the ASCA normalization. This object may be one of the bright examples of a type-II QSO population at high redshift, previously undetected in optical surveys. The hard X-ray spectrum of this object suggests that such a population could make a substantial contribution to the X-ray background., Comment: 7 pages, to appear in MNRAS
- Published
- 1998
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21. ASCA observations of Deep ROSAT fields - III. The Discovery of an Obscured Type 2 AGN at z=0.67
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Boyle, B. J., Almaini, O., Georgantopoulos, I., Blair, A. J., Stewart, G. C., Griffiths, R. E., Shanks, T., and Gunn, K. F.
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Astrophysics - Abstract
We report on the discovery of a narrow-emission-line object at z=0.672 detected in a deep ASCA survey. The object, AXJ0341.4-4453, has a flux in the 2--10keV band of 1.1+/-0.27 E-13 erg/s/cm**2, corresponding to a luminosity of 1.8E44 erg/s (q0=0.5, $H0 = 50km/s/Mpc. It is also marginally detected in the ROSAT 0.5-2keV band with a flux 5.8E-15 erg/s/cm**2. Both the ASCA data alone and the combined ROSAT/ASCA data show a very hard X-ray spectrum, consistent with either a flat power law (alpha < 0.1) or photoelectric absorption with a column of nH > 4E22 cm**-2 (alpha = 1). The optical spectrum shows the high-ionisation, narrow emission lines typical of a Seyfert 2 galaxy. We suggest that this object may be typical of the hard sources required to explain the remainder of the X-ray background at hard energies., Comment: MNRAS accepted, 5 pages, 2 figures
- Published
- 1998
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22. Faint galaxies and the X-ray background
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Almaini, O., Shanks, T., Boyle, B. J., Georgantopoulos, I., Griffiths, R. E., Stewart, G. C., Gunn, K. F., and Blair, A. J.
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Astrophysics - Abstract
We summarise our recent work on the faint galaxy contribution to the cosmic X-ray background (XRB). At bright X-ray fluxes (in the ROSAT pass band), broad line QSOs dominate the X-ray source population, but at fainter fluxes there is evidence for a significant contribution from emission-line galaxies. Here we present statistical evidence that these galaxies can account for a large fraction of the XRB. We also demonstrate that these galaxies have significantly harder X-ray spectra than QSOs. Finally we present preliminary findings from infra-red spectroscopy on the nature of this X-ray emitting galaxy population. We conclude that a hybrid explanation consisting of obscured/Type 2 AGN surrounded by starburst activity can explain the properties of these galaxies and perhaps the origin of the entire XRB., Comment: Proceedings of the X-ray Surveys Workshop. To appear in Astron Nachr., 4 pages, 7 encapsulated figures, uses xsurv_article macro (included). Revised version with correct figure annotation, plus other minor changes. Also available from http://www.ast.cam.ac.uk/~omar/astro.html
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- 1997
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23. ASCA observations of Deep ROSAT fields - II. The 2-10keV AGN luminosity function
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Boyle, B. J., Georgantopoulos, I., Blair, A. J., Stewart, G. C., Griffiths, R. E., Shanks, T., Gunn, K. F., and Almaini, O.
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Astrophysics - Abstract
We present additional optical spectroscopic identifications of sources identified in three deep ASCA GIS fields which also form part of a deep ROSAT survey. In total, 26 ASCA sources have been detected down to a 2-10keV flux limit of S = 5e-14 erg/cm/s. LDSS observations have increased the spectroscopic completeness of the survey to between 65 and 85 per cent, with identifications for up to 13 QSOs with broad emission lines and 6 objects with narrow emission lines. Combining these objects with the AGN identified in the LMA/HEAO-1 sample by Grossan, we find evidence for significant cosmological evolution in the 2-10keV band (
=0.63+/-0.03), fit by a pure luminosity evolution model; L \propto (1+z)^k, k=2.04^{+0.16}_{-0.22}$. The present-epoch 2-10keV AGN X-ray luminosity function, \Phi(L_X), is best represented by a two power law function: \Phi(L_X) \propto L^{-3.0}, L*>10^{44.1}erg/s; $\Phi (L_X) \propto L^{-1.9}$, L*<10^{44.1}erg/s. Depending on the extent to which we extrapolate the z=0 AGN luminosity function, we predict a total contribution to the 2-10keV X-ray background from QSOs and narrow-emission-line galaxies which ranges from 48 per cent (for AGN with L>10^{42}erg/s) to 80 per cent (L>10^{39}erg/s)., Comment: 10 pages, TeX, 5 figures, MNRAS in press (significant revision at proof stage) - Published
- 1997
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24. The Baryon Catastrophe and the multiphase intracluster medium
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Gunn, K. F. and Thomas, P. A.
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Astrophysics - Abstract
We review the theories and observations which together have led to the concept of the Baryon Catastrophe: observations of the baryon fraction on the scale of clusters of galaxies appear to be at least three times as high as the universal baryon fraction predicted by the theory of primordial nucleosynthesis in a flat, $\Omega_0 = 1$, universe. We investigate whether this discrepancy could be eliminated by treating the intracluster gas as a multiphase medium, and find that this treatment both lowers the calculated mass of gas in a cluster and increases the inferred gravitational potential. These combined effects can reduce the calculated baryon fraction by between a quarter and a half: the precise amount depends upon the volume fraction distribution of density phases in the gas but is independent of the temperature profile across the cluster. Thus moving to a multiphase intracluster medium cannot resolve the Baryon Catastrophe by itself; other possible causes and explanations are discussed., Comment: uuencoded postscript file, 2 figures included
- Published
- 1995
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25. How much upwelling occurs in the abyssal bottom boundary layer?
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McDougall, T., Holmes, R., and Gunn, K.
- Abstract
We examine (i) what sets the vertical stratification in the abyssal ocean, and (ii) the rate of upwelling of water in the bottom boundary layer of the abyssal ocean. We restrict attention to the bottom-most, densest, 2000m of the ocean and analyse the buoyancy budget in buoyancy coordinates, taking into account the bottom-intensified nature of the rate of diapycnal mixing in the ocean. This bottom-intensified nature of diapycnal mixing means that the diapycnal velocity in the ocean interior is downwards towards denser fluid, and all the diapycnal upwelling occurs in the first ~50m above the sea floor, with the upwelling transport in this Bottom Boundary Layer often being two or three times the net diapycnal upwelling needed to balance the sinking transport of Antarctic Bottom Water.The geometry and conservation equations of this problem can be described as a steady-state filling-box problem. The rate of sinking of dense Antarctic Bottom Water and the area-integrated diffusive buoyancy flux across the upper-most buoyancy surface are both regarded as given input parameters, which gives the buoyancy contrast between the sinking Antarctic Bottom Water and the value of buoyancy on this upper-most surface. We show that the vertical stratification in the interior abyssal ocean is then entirely determined by knowledge of the rate of detrainment (or entrainment) of plume fluid out of (into) the sinking plume and into (out of) the ocean interior. This knowledge is equivalent to knowledge of the area-integrated diffusive buoyancy flux on the buoyancy surfaces in the abyss., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)
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- 2023
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26. Distributed MPC applied to power demand side control.
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Gunn K. H. Larsen, Jarno Pons, Sietse Achterop, and Jacquelien M. A. Scherpen
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- 2013
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27. Distributed MPC for controlling μ-CHPs in a network.
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Gunn K. H. Larsen, Sebastian Trip, Nicky D. van Foreest, and Jacquelien M. A. Scherpen
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- 2012
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28. The Impact of Sporadic Campylobacter and Salmonella Infection on Health and Health Related Behaviour: A Case Control Study
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Smith, G. E., Lewis, M., Paterson, S., Gray, J., Gunn, K., Farrington, F., and Croft, P.
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- 2002
29. Distributed MPC Applied to a Network of Households With Micro-CHP and Heat Storage.
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Gunn K. H. Larsen, Nicky D. van Foreest, and Jacquelien M. A. Scherpen
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- 2014
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30. Distributed Control of the Power Supply-Demand Balance.
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Gunn K. H. Larsen, Nicky D. van Foreest, and Jacquelien M. A. Scherpen
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- 2013
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31. 'She'll Be Right, Mate': A Mixed Methods Analysis of Skin Cancer Prevention Practices among Australian Farmers-An At-Risk Group.
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Trenerry, C, Fletcher, C, Wilson, C, Gunn, K, Trenerry, C, Fletcher, C, Wilson, C, and Gunn, K
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This study examined Australian farmers' engagement with skin cancer prevention behaviours and explored what made it hard for them to be 'SunSmart' (barriers), and what could be done to make prevention easier (facilitators). In total, 498 farmers (83.1% male, 22-89 years, 50.8% grain, sheep, or cattle farmers) participated. The least frequently performed SunSmart behaviours (reported as never practiced during summer) were using SPF 30+ sunscreen (16.6%), wearing protective sunglasses (10.5%), and wearing protective clothing (8.6%). Greater engagement (i.e., higher scores on scale from Never to Always) with SunSmart behaviours was explained by gender (female), educational attainment (trade or technical college certificate vs. high school), personal skin cancer history, and skin sun sensitivity. Barriers reported by farmers related to personal preferences (e.g., short-sleeved rather than long-sleeved clothing), comfort, and perceived impracticality of sun protection. Farmers' solutions included making protective clothing and sunscreen more appropriate for farm work (e.g., by making clothing more breathable). A personal health scare was the most reported motivation for skin cancer prevention. Findings highlight the need for increased access to sun-protective clothing and sunscreen that is suitable for wearing when working on farms, complemented by culturally appropriate health education messaging, to encourage more farmers to perform SunSmart behaviours.
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- 2022
32. The Effect of Mechanical Forces on the Exudation of Organic Substances by the Roots of Cereal Plants Grown under Sterile Conditions
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Barber, D. A. and Gunn, K. B.
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- 1974
33. Premature ejaculation: definition and prevalence
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Carson, C and Gunn, K
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- 2006
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34. Whole blood use and patient outcomes in critical bleeding: Results from the Australian and New Zealand massive transfusion registry (ANZ-MTR).
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McQuilten Z., Badami K., Charlewood R., Gunn K., Ure B., Wellard C., Wood E., Haysom H., Sparrow R., Waters N., McQuilten Z., Badami K., Charlewood R., Gunn K., Ure B., Wellard C., Wood E., Haysom H., Sparrow R., and Waters N.
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Aim: Using Australian and New Zealand (NZ) Massive Transfusion Registry (ANZ-MTR) describe Whole Blood (WB) use in massive transfusion (MT) (>=5 red blood cells (RBC) in any 4 h period) in NZ and compare transfusion requirements, laboratory parameters and patient outcomes for WB recipients (WB-R) with those receiving only RBC units (RBC-R). Method(s): All adult MT recipients between 2011 and 2018, at 4 NZ sites with access to WB, were included in the analysis. Result(s): Three hundred fifteen of 1947 (16.1%) MT recipients received >=1 WB unit. WB was most commonly used in vascular surgery (21%), trauma (17%), gastrointestinal (14%), cardiac surgery (11%). WB-R received a median of 2 (IQR 1, 2) WB units and commenced transfusion sooner relative to time of hospital admission than RBC-R. WB-R received fewer RBC (9 (6,16) vs 10 (7,15), P = 0.013), more fresh frozen plasma (FFP) (6 (2,11) vs 5 (2, 9), p < 0.001) and more recombinant FVIIa (P = 0.02) than RBC-R. There were no differences in fibrinogen concentrate, prothrombin complex or other fresh blood products given. In first 4-h of MT, WB-R had shorter APTT compared to RBC-R (42 (34, 60) vs 47 (36, 71) seconds; P = 0.01). Nadir haemoglobin, platelet count and fibrinogen for the 2 groups were similar. WB-R had higher in-hospital mortality (31.4% vs 25.3%, P = 0.024), but similar ICU length of stay and ventilation time. After adjusting for age, sex, number of RBC and FFP units, clinical context and hospital site there was no significant association between WB use and mortality (adjusted odds ratio WB Plasma Reduced 1.19 (95% CI 0.80-1.78) and WB Leucodepleted 1.42 (95% CI 0.94-2.15)).
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- 2020
35. Expression of immunogenic VP2 protein of infectious bursal disease virus in Arabidopsis thaliana
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Wu, H., Singh, N.K., Locy, R.D., Scissum-Gunn, K., and Giambrone, J.J.
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- 2004
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36. Machine Learning of Infant Spontaneous Movements for the Early Prediction of Cerebral Palsy: A Multi-Site Cohort Study
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Ihlen, Espen A. F., primary, Støen, Ragnhild, additional, Boswell, Lynn, additional, de Regnier, Raye-Ann, additional, Fjørtoft, Toril, additional, Gaebler-Spira, Deborah, additional, Labori, Cathrine, additional, Loennecken, Marianne C., additional, Msall, Michael E., additional, Möinichen, Unn I., additional, Peyton, Colleen, additional, Schreiber, Michael D., additional, Silberg, Inger E., additional, Songstad, Nils T., additional, Vågen, Randi T., additional, Øberg, Gunn K., additional, and Adde, Lars, additional
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- 2019
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37. The time course of binding to striatal dopamine D2 receptors by the neuroleptic ziprasidone (CP-88,059-01) determined by positron emission tomography
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Bench, C. J., Lammerstma, A. A., Grasby, P. M., Dolan, R. J., Frackowiak, R. S. J., Warrington, S. J., Boyce, M., Gunn, K. P., and Brannick, L. Y.
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- 1996
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38. COMBATING COAGULOPATHY: TS12
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GUNN, K. N.
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- 2007
39. Dose dependent occupancy of central dopamine D2 receptors by the novel neuroleptic CP-88,059-01: a study using positron emission tomography and11C-raclopride
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Bench, C. J., Lammertsma, A. A., Dolan, R. J., Grasby, P. M., Warrington, S. J., Gunn, K., Cuddigan, M., Turton, D. J., Osman, S., and Frackowiak, R. S. J.
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- 1993
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40. Prevalence of urinary catheterization in UK nursing homes
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McNulty, C, Freeman, E, Smith, G, Gunn, K, Foy, C, Tompkins, D, Brady, A, and Cartwright, K
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- 2003
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41. Characterisation of aluminium release by the enFlow® fluid‐warming system in crystalloids and blood products
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Taylor, M. H., primary, Choi, D., additional, Fitzpatrick, S. M., additional, and Gunn, K. N., additional
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- 2019
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42. Improvements to the Eddy Viscosity Wind Turbine Wake Model
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Gunn, K, primary
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- 2019
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43. 1-A: If You Build it They Will Come—and More Will Stay: Increasing Retention Through a Modified Team-Based Learning Approach in an Introductory Biology Course for Allied Health and Other Majors at a Junior College
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Beumer, A.E., Briggs, A.G., Sanderson, S.K., Morgan., S.K., Caldari, C., Carson, S., Caruso, J.P., Israel, N., Lovelace, M., Saunders, M.J., DeBoy, C.A., Gabriel, S.G., Peterson, M.P., Gollery, S.W., Gunn, K., Ward, D.P., Staiger, J.W., McCauslin, C.S., Humphreys, T.L., Kleinschmidt, A.M., Nelson, M.K., Keler, C., Linden, M.L., Lirot, J.A., Gildea, H.K., Jang, E.V., Jones, J.C., Maris, M.D., Marizzi, C., Nash, B., Nisselle, A., Florio, A., Lee, M., Micklos, D.A., McPheron, L.J., Mixter, P.F., Wang, S.C., O’Connor, C.M., Rowedder, H., Warner, D.M., Reeves, T.D., Peteroy-Kelly, M.A., Buraei, Z., Marcello, M., Strahs, D., Zuzga, D., Crispo, E., Regassa, L.B., Cawthorn, M., Svec, L., Vives, S.P., Rowland-Goldsmith, M.A., Toto, C., Silverman, E.J., Schmidt, J.A., Crisucci, E.M., Shanmuganathan, A., Soneral, P.A.G., Wyse, S.A., Tawde, M., Boccio, D., Kolack, K., Wagner, S.C., Sullivan, G.A., Canterberry, S.C., Taylor, J., Walker, R.J., Jones, N., Sapkota, K., and Zwick, M.
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ASMCUE Abstracts - Abstract
Retention and performance in introductory biology classes is a challenge for many institutions, particularly at two-year schools. Active learning, practice, peer lead workshops and structure have all been shown to increase performance in these classes. A meta-analysis by Freeman et al. (2014) showed that science courses that incorporate active learning increase exam scores and the chance of passing the course. Arbruster et al. (2009) showed an increase in exam scores and student engagement in introductory biology courses specifically. Retrieval and practice have also been shown to increase learning (Karpicke and Blunt 2011, Freeman et al. 2007). In 2009, Ralph Preszler demonstrated that peer lead workshops increase student learning and engagement in introductory biology courses. In teaching past courses I used lecture combined with questioning of the entire class, sometimes with clickers sometimes using the traditional raised hand method, and case studies; however, students did not come to class prepared, leading to repetition of the basic material in the text during lecture and leaving little time for active learning exercises. This lead to a major reorganization of all my classes in the summer of 2013. The reorganized classes included Bio 101, a first semester biology course for nonmajors ranging from pre-nursing to business to art majors. Bio 101 covers basic chemistry, the cell, energy transfer, genetics, and evolution, and has a high drop rate, similar to other institutions. A modified Team Based Learning (TBL) format, with built-in increased active learning, recall, structure and peer lead work, was expected to give an increase in retention and exam scores in introductory biology courses. The modified team-learning method used combined TBL, as outlined in Michaelson et al. (2003), with various lecture lengths and application types. Teams were formed at the beginning of the semester and remained for the entire semester. Readiness assessment tests (RATs) were based on readings and other supplementary material provided on Blackboard. RATs were taken first individually (iRAT) then as a team (tRAT). RATs were evaluated for areas of confusion and followed by lecture on these topics. After lecture, various types of applications were implemented including case studies, problem sets, or discussion/acting. Four tests were given during each semester. Retention and average exam scores in introductory biology courses taught by the same instructor were compared between the 2012 and 2013 academic years. In 2012, lecture combined with moderate use of case studies and other types of active learning (clickers) were used. Two sections of Bio 101 were taught in the fall of 2012 and three sections in the spring of 2013, for a total of 170 students. The modified TBL approach was implemented in 2013 as described above. One section was taught in each semester of the 2013 academic year for a total of 42 students. Implementing the modified TBL format lead to a 10% decrease in student withdrawals from the course. The average final grade was 0.20 grade points higher after implementation. In addition there was a 14% increase in students passing the course (D or above) and a modest (6%) increase in students earning a C or higher. There was a small, but statistically significant increase in overall average exam scores and for exam one (t-test, p0.05). These data support work that has been done in other introductory biology classrooms and demonstrate that the above changes in course format can benefit students enrolled in two-year institutions. ASM Curriculum Guideline Concept(s): Advancing STEM education and research Pedagogical Category(ies): Course design, Teaching approaches, The goal of the present study was to use a concept-mapping task to gauge student understanding of the Central Dogma of molecular biology. Concept maps challenge students to assimilate new concepts into existing frameworks, and thus require the ability to synthesize new information. The hypothesis guiding this study is that student performance on concept maps reveals specific Central Dogma misconceptions gained, lost, and retained by students. Students in two sections of a genetics course at Beloit College completed pre- and posttest concept mapping tasks using 27 terms related to the Central Dogma. Each map was scored in two ways: 1) complexity (total number of linking verbs, also known as propositions, used), and 2) propositional validity (number of valid propositions/total number of propositions). A comparison of pre- and post-test map scores revealed a statistically significant increase in both complexity (p, The use of case studies as a method of teaching is known to improve concept knowledge as well as critical thinking, making it a superior option to lecture-based learning. Peer-instruction and use of clicker questions are types of active-learning that have also been shown to improve student performance in STEM courses. The objective of this study was to design a laboratory exercise for an upper-level biology course that would incorporate peer-instruction and case studies with the use of a clicker response system. Students (n=19) were separated into groups of three or four. They were presented with a scenario regarding a patient who was demonstrating symptoms of pathology and were asked to use the clickers to individually select an answer from a multiple choice question about the scenario presented (individual selection). The questions were categorized as testing “knowledge,” “comprehension,” “analysis,” and “synthesis” under Bloom’s taxonomy. Once the class voted, the histogram was shown, and, if there was < 80% consensus for the correct answer, students had to discuss their answers as a group (peer-group instruction) and re-vote as a group. If < 80% consensus was still observed, each group took turns discussing their answer with the rest of the class (peer-class instruction), and the class re-voted. Each case study had five to six questions, and three case studies were utilized throughout the semester. Correct student answers before and after peer instruction were quantified, and a survey was performed at the end of the semester to measure student satisfaction. On average, 55.4%, 83.5%, and 94.7% of students picked the correct answer after individual selection, peer-group instruction, and peer-class instruction, respectively. Additionally, students rated the exercise an average of 4.8 on a scale of 1 to 5 asking how much they enjoyed the exercise. These results suggest that the use of peer instruction and clicker questions in case study–based learning improves critical thinking as well as application and analysis of concepts for upper-level biology students, and should be explored further as a model for undergraduate biology teaching. ASM Curriculum Guideline Concept(s): Advancing STEM education and research Pedagogical Category(ies): Student learning, TH!NK is a new initiative at NC State University focused on enhancing students’ higher-order cognitive skills. As part of this initiative, I explicitly emphasized critical and creative thinking in an existing bacteriophage discovery first-year research course. One strategy that I employed to enhance students’ critical thinking skills was the use of discipline-specific, real-world scenarios. As an in-class activity, students participated in responding to and discussing a number of critical thinking scenarios over the course of the semester. In this paper, I share a general “formula” for writing scenarios, as well as several specific scenarios I created for my course. I also present how embedding aspects of the scenarios in assignments such as lab reports and reviews of the primary literature enrich these activities. I assessed student gains in critical thinking skills using a pre-/posttest model of the Critical Thinking Assessment Test (CAT), developed by Tennessee Technological University. I observed a positive gain trend in most of the individual skills assessed in the CAT, with a statistically significant large effect on critical thinking skills overall. The strategies described here can be modified for use in biology and other STEM disciplines, as well as in diverse disciplines in the social sciences and humanities. ASM Curriculum Guideline Concept(s): Advancing STEM education and research Pedagogical Category(ies): Student learning, Teaching approaches, Teaching tools, Undergraduate research is known to increase STEM student achievement (Russell et al. 2007, Lopatto 2007, Villarejo et al. 2008), so the Small World Initiative (SWI), which has STEM students discover novel antibiotics in undergraduate labs, was tested to see whether it improved student success. We adapted the SWI to a Florida Atlantic University Introductory Biology nonmajors lab using a regular lab section by the same TA as a control. Our hypothesis was that SWI students would earn higher grades and critical-thinking posttest scores than controls. Students in both groups took one of three lecture sections from two different instructors. California Critical Thinking Skills Test (CCTST) Pre- and Posttests were offered to both groups for ∼1.5% lab extra-credit. Labs started with 22 SWI and 24 controls. All SWI students completed lab and 21 earned above C-. Two controls dropped the course, but 22 earned above C in lab (control lab average=88%). All SWI students earned above C in lecture, but 6 of 22 controls had below D+ and three failed. A two-tailed Fisher’s exact test comparing SWI vs. controls for percentage of students earning above C and percentage earning below D+ in lecture showed SWI students had significantly better lecture grades (pp, Previous data have indicated that an activity in which students use their own basal body temperature to predict hormone changes increases learning outcomes. In this study I am investigating whether using data collected from one’s self improves learning outcomes and/or student engagement compared with the same activity in which data are not collected from one’s self but provided. My hypothesis is that both learning outcomes and student engagement will be higher in groups that collect self data. To test this hypothesis, I compared student survey results and changes in the percentages of correct quiz answers before and after students completed two activities in which half of the students collected data from themselves and the other half used data that were provided. In one activity, students predicted hormonal changes associated with the menstrual cycle based on basal body temperature. In the other activity, students predicted levels of hormones associated with the stress response based on changes in pulse and stress perception before and after stress reduction techniques. The class of 15 was divided so that each student collected her own data for one activity and used data that was provided for the other. Survey results indicate that 14 out of 15 students prefer collecting data on themselves, suggesting that data collection from self is an effective strategy to engage students. Whichever group used self data showed a greater increase in the average percentages of correct quiz responses after the activity. The average percentage of correct responses (out of 10) increased after the basal body temperature activity from 54% to 72% (p, The 2012 President’s Council of Advisors on Science and Technology (PCAST) report highlighted the growing issue of persistence of STEM majors and encouraged significant change. In an effort to understand the factors which affect STEM retention at Viterbo University, three years ago, an internal study showed the strongest indicator of student success in the freshman year (defined as grades of C or higher) in math/science courses is high school grade point average (HS GPA). Specifically, in General Chemistry I, 80% of students who achieved less than a C had a HS GPA below 3.3. In contrast, only 30% of students who received a C had a HS GPA below 3.3, and none of the students who received a grade higher than C had a HS GPA below 3.3. This past fall, after integrating several active learning initiatives in the STEM curriculum, we returned to the General Chemistry classroom to examine indicators of student success in the first year. We hypothesized that academic performance would still be a key indicator of student success, but we also hypothesized that student attitudes would be critical components in student success. Pair-wise correlations revealed that many of the survey attitudes (measured by the Motivated Strategies for Learning Questionnaire (MSLQ), a validated survey on student learning and motivation) and measures of student success were correlated. This suggests that the final grade in the class is positively correlated with several of the attitudes measured. While multiple testing raises concerns about false-positives, these factors, in addition to others, are included in the best multiple linear regression model to predict final grade. However, the strong colinearity of the attitudes makes identification of which attitudes in particular influence student success difficult. This colinearity was confirmed using a principal components analysis that a substantial proportion of variance in all measured attributes can be accounted for in a single principal component. In addition, this component is strongly correlated with final grade, suggesting that much of the variance can be explained by the fact that strong students score highly on all measured attributes. Future work will use these achievement and attitude measures as baseline data and see how changes to the pedagogy affect these values. ASM Curriculum Guideline Concept(s): Advancing STEM education and research Pedagogical Category(ies): Teaching approaches, Evidence that active and inquiry learning increase student retention and critical thinking skills is conclusive, yet many undergraduate students protest against shifts in pedagogy because it is more work for them than lectures and exams. Engaging students’ interest so that they value investing time and effort in learning is as important as incorporating active and inquiry learning in courses. I tested whether including creative nonfiction books in one-semester majors microbiology courses would promote student engagement, supplementing Brock Biology of Microorganisms with Sachs’ Good Germs, Bad Germs, which chronicles the development of the hygiene hypothesis and the growing antibiotic resistance threat, and Ben-Barak’s The Invisible Kingdom, highly humorous essays on the manifold capabilities of microbes. We discussed how these popular reading assignments related to content throughout the course. I predicted that reading less content-dense creative nonfiction would increase student interest in learning microbiology because it emphasizes how microbes impact people’s lives and tells stories about working microbiologists in a suspenseful way. Contrary to my hypothesis, 76% of students in spring 2012 and spring 2014 microbiology courses at Sierra Nevada College reported on end-of-term surveys that they found the popular books less valuable for the course than the text, homework, and exam review materials. Students’ free comments suggested that the majority still valued course assignments based on how directly they helped them prepare for exams, although non-exam assessments contributed at least 54% to the course grade. A few students commented that Good Germs, Bad Germs and The Invisible Kingdom were interesting and helped them see applications for microbiology and 5% of students valued them more than the text, commenting that the text was too hard to understand. Although free comments are subject to interpretation and the total sample size was just 21 students, I conclude that creative nonfiction reading assignments do not increase engagement for the majority of undergraduates. ASM Curriculum Guideline Concept(s): Systems, Impact of microorganisms Pedagogical Category(ies): Teaching tools, Introduction: Quantitative polymerase chain reaction (qPCR) has become an essential and standard technique in molecular biology research laboratories. In 2012, we reasoned it would be fitting to incorporate a qPCR laboratory module into a mandatory sophomore Genetics course, providing every Biology/Biochemistry/Environmental Science major with hands-on qPCR experience. For undergraduates, performing qPCR simply requires micropipetting proficiency; conceptual understanding is the difficult hurdle. Methods: Across three years, we developed and tested three versions of a structured inquiry lab exercise. The exercises introduce students to the concept, purpose, and performance of qPCR technology and use: 1) three target genes, inflammation as a model system, and comparison of tissue culture cells treated with five different inflammation-inducing treatments; 2) one target gene, inflammation, and five treatments; or 3) one target gene, cancer as a model system, and comparison of primary and immortalized cells. We developed 1) a pre-/posttest to gauge student knowledge and understanding at the onset/conclusion of the module and 2) a set of open-ended postlab discussion questions. Hypothesis: We hypothesized the third iteration, placing qPCR in the context of cancer and telomerase, would be most successful. Results: In all iterations, scores were significantly higher on posttests. Pretest and posttest scores were highest in the third version. All assessment scores increased from the first to the third iteration, and instructors reported greatest student engagement in the third version. Conclusion: Data analysis after Year 1 suggested analyzing three target genes interfered with comprehension. Accordingly, we reduced to analysis of one target gene. Student difficulties persisted, indicating challenges with cell treatments and inflammation. We shifted to a more straightforward focus on cancer, uncontrolled cell growth, and telomerase, reasoning it also might hold more student interest. Improvements in assessment test scores indicate our modifications have resulted in a refined module that enhances student learning and understanding of qPCR. ASM Curriculum Guideline Concept(s): Pathways, Advancing STEM education and research Pedagogical Category(ies): Hands-on projects, Student learning, Since 1942, all students graduating from Allegheny College have been required to complete a junior seminar and a senior research project. As of 1999, all students have also been required to complete three writing and speaking classes during their first two years. The first two, taken in the first year, are interdisciplinary; a third, taken in the second year, is disciplinary in nature. Coincident with the revision of the college curriculum, the Biology Department completed a self-study and external review which revealed that both faculty and students were dissatisfied with our three-semester lecture and lab introductory series. Consequently, laboratories were dropped from the first two courses, and the third course was reworked as a version of the sophomore-level writing and speaking class, emphasizing experimental design, research methods, analysis and interpretation of data, and written and oral communication. To provide students with experiences in different biological subdisciplines, the course is modular in format, with each module focused on an instructor-specific research question that provides students with an opportunity to develop research projects. The final products of each module are a research presentation and a primary literature–style paper. We hypothesized that this course would provide students with authentic research experiences and facilitate their understanding of writing and speaking in the discipline. Two mechanisms of assessment were used to determine whether our hypothesis was supported. We used a multi-year, Likert-scale attitude survey, where, for example, over 85% of the students rated the course a 4 or 5 for their learning gains in presenting data in journal article format. We also used the nationally recognized classroom undergraduate research experience (CURE) survey; our students’ self-reported gains in categories such as ability to read and understand scientific literature and skill in science writing exceeded those of the “all students” comparison group, which includes participants in summer research. Thus, the course provides an authentic research experience that simultaneously enhances the students’ writing and speaking skills. ASM Curriculum Guideline Concept(s): Advancing STEM education and research Pedagogical Category(ies): Course design, Too often in a predetermined or “cookbook” laboratory, students do not make the connection between experiential methods, the concepts behind these methods, and the application of these methods to different situations. This semester-long laboratory exercise was designed to provide students with an inquiry-based or classroom undergraduate research experience (CURE) laboratory project that incorporates commonly used microbiological lab concepts and techniques and to see whether this type of laboratory could be used to enhance student learning and understanding of these concepts and techniques. The theme of this lab project is centered on plant-microbe interactions. Plant growth–promoting bacteria (PGPR) found in the rhizosphere can easily be isolated from plant roots using a defined selective media. Students learn and use standard microbiological techniques, such as serial dilution and enumeration, selective and differential media, staining, biochemical testing, 16S rDNA bacterial identification, record keeping and data analysis, characterization and identification of their bacterial isolates. Students also test their isolates for plant growth promotion, auxin production, phosphate solubilization, fungal inhibition and antibiotic resistance profile, and analysis of their data and the entire class data (class size is 75 to 90 students). A Student Assessment of their Learning Gains (SALG) survey (www.salgsite.org) was distributed to students in three consecutive fall semesters to assess their learning gains of the various concepts and techniques learned in laboratory and lecture. Student-perceived learning gains of this lab project were very positive. With 5.0 being the greatest gain and 4.0 being a good gain, all but one of the mean gains for the three semesters combined was greater than 4.0. For example, the mean gain for the students’ understanding of bacterial isolation and serial dilution was 4.4, the mean gain for bacterial identification was 4.4, the mean gain for aseptic technique was 4.6, the mean gain for notebook and record keeping was 4.3 and the mean gain for data analysis was 4.2. The only gain which was less than 4.0 was the mean gain of 3.9 for selective and differential media. Using the cross tabulation tool on the SALG website to compare learning gains of concepts with learning gains for techniques, again, most of the cross tabulations ended up in the good gain and great gain blocks. These data clearly confirm that students can learn important laboratory techniques in an inquiry-based or CURE type lab and maybe have a better understanding of how to apply the concepts that they have learned. Student comments also support this idea. For example, students were asked to comment on how their understanding of the subject has changed, what skills they have gained, and how their attitude toward the subject has changed. Some of these comments were the following: “It helped me piece the lecture material and lab material together to better understand why we are learning what we are in lecture.” “I feel that I now have a deeper understanding of the procedures talked about in lecture.” “I have grown to understand the necessity of a well-organized and thorough notebook when performing research.” “Throughout lab, I feel as though I have successfully understood and applied skills learned. I have a better understanding of how to perform serial dilutions, a concept first introduced some time ago. I also feel confident in my aseptic technique, a skill that will help with future work.” “I understand and can apply different media depending on what bacteria are being isolated.” “I understand how to analyze the data observed.” “I liked that we were able to use a real-life scenario in order to learn microbiology.” “This class has increased my interest in microbiology and I am looking into doing a student research project involving what I learned.” “I had a lot of fun with this lab. I enjoyed the one ultimate goal vs. other labs I have had with lots of small goals in mind; it helped me focus on what was really happening.” Comparing attendance from the year before this lab was done with the first year the lab was done, there was a 3% decrease in the number of students missing two or more labs during the semester and a 4% decrease in the number of students missing one lab session. There are no survey data for attendance, so no definitive conclusions can be drawn from this attendance data, but a number of students commented that they wanted to come to lab each week to work on their bacterium. Student ownership and involvement with their isolation and characterization project has also led to interested students using their isolates in undergraduate research projects, something which would not usually result from a traditional lab. Over the past four years there have been nine students who completed research projects using the PGPR. Also, interesting isolates are used by the students in subsequent courses, Molecular Biology and Virology. The ability to do this reinforces the idea for the students that science is an ongoing project not just a once-and-done type laboratory. The data collected using the SALG survey support the use and development of inquiry-based labs for microbiology students. Not only are the students able to connect concepts with techniques in these labs, they also help keep the lab exercises current, stimulating, and challenging for the students and the instructors. ASM Curriculum Guideline Concept(s): Impact of microorganisms, Advancing STEM education and research Pedagogical Category(ies): Course design, Students often rely on rote study methods when preparing for exams. Conversely, exams at the college level and above stress higher-order cognitive thinking skills. To address this disconnect, students in an intermediate-level neuroscience course were provided with individually tailored, detailed exam feedback highlighting student performance on each level of Bloom’s taxonomy. This feedback, accompanied by a presentation of Bloom’s taxonomy and specific study suggestions for each of its levels, was provided to the students in hopes that their exam performance on higher-order exam questions would improve. To assess the effects of this intervention, exam results from the semester with the intervention (2014) were compared with exam results from the previous year’s course (2013) without the intervention (mixed-design ANOVA, post-hoc t-tests with Bonferroni correction). In both years, students increased their exam performance throughout the semester. Students’ performance on higher-order questions improved more throughout the semester in 2014 compared with 2013 (p, Active learning promotes student engagement, increases learning gains, enhances long-term retention, and enables development of higher-order thinking skills. This study examined the efficacy of active learning in graduate and medical school classroom-based (lacking a lab) courses. It stemmed from a prior observation that students perform poorly on exam questions requiring an understanding of lab-based techniques, a topic previously taught by didactic lecture. To investigate the hypothesis that active learning leads to greater learning gains than lecture, a flipped-classroom approach was implemented for this topic since these courses lack a lab component. Students wrote and performed skits based on clinical scenarios for which techniques are used for diagnosis and treatment. This approach was selected to demonstrate real-world relevance and applications. Student learning was quantitatively assessed by multiple-choice questions (MCQs). Data were analyzed using paired t-test; differences were significant. Masters student performance on multiple choice questions (MCQs) for this topic ranged from 77% to 100% and averaged 86% versus a 72% average for MCQs based on material taught by lecture. Medical student performance on MCQs for this topic ranged from 74% to 99% and averaged 90% versus a 76% average for MCQs based on material taught by lecture. Student attitudes toward active learning were assessed by an optional, anonymous survey and a required reflection. Masters students’ survey responses and free-response reflections supported their positive attitudes toward engagement in active learning. Medical students’ survey responses and free-response reflections were mixed, ranging from strongly positive to strongly negative, indicating their perceptions of learning strategy efficacy are not necessarily aligned with empirical data. From these data, I conclude that, within this context, active learning is more effective than lecture-based approaches. These data contribute to the research indicating that active learning leads to increased learning gains and support active learning approaches as effective, empirically validated teaching practices. ASM Curriculum Guideline Concept(s): Advancing STEM education and research Pedagogical Category(ies): Teaching approaches, Rapid developments in DNA sequencing technology continue to advance microbiology, creating opportunities for the next generation of scientists. We developed the Urban Barcode Research Program (UBRP) to engage high school students to study biodiversity in New York City (NYC) using DNA technology. The UBRP supports independent, student-driven research, spanning study design, sample collection, DNA extraction, sequencing, analysis, and scientific communication. We hypothesized that having high school students work with a scientist would increase their ability to conduct science, and the experience would be comparable with an undergraduate student research experience. We evaluated the UBRP using mixed methods, including the validated Survey of Undergraduate Research Experiences (SURE-III) to measure changes in attitudes towards STEM studies and careers and learning gains around the scientific process, ranging from lab skills to academic, cognitive, and attitudinal aspects. Qualitative data included free-text survey responses, semi-structured interviews and project artifacts and will be presented in more detail at the conference. In year 1, 42 students (50% underrepresented minorities) worked with 18 scientists at 11 NYC institutions. Postsurvey data showed that for the majority (90.6%, n=35), the UBRP influenced them to continue research. Comparing the SURE-III results with reference college-level data (n≤2762) showed UBRP student learning gains were either equivalent (12 of 21 items) or higher (6 of 21), with highest gains for laboratory techniques (4.15 UBRP vs. 3.80 college students on a 5-point Likert scale of 1=no gain to 5=very large gain) and understanding how scientists work on real problems (3.94 vs. 3.51). Interestingly, students in our Urban Barcode Program (UBP; n=196), mentored by science teachers, not scientists, showed equivalent college-level learning gains in only 3 of the 21 items. These data support both our hypotheses: having high school students work with a scientist increases their ability to conduct science and provides a comparable college-level experience. ASM Curriculum Guideline Concept(s): Impact of microorganisms, Advancing STEM education and research Pedagogical Category(ies): Hands-on projects, Student learning, College students often have difficulty mastering the language required in a general biology course, and the use of science terminology may interfere with their ability to learn difficult concepts. I tested the hypothesis that students are more likely to learn concepts when they are first introduced using plain, everyday language rather than scientific terminology. I did this through a comparative approach in a General Biology (nonmajors) course at Berkeley City College. I taught two sections of material: understanding experimental design and introductory genetics. Each section was taught using scientific terminology one semester and plain language the other semester. Students were assessed using a pre-/posttest directly before and after the section was taught; learning gains were compared across the two groups. Students’ ability to understand scientific experimentation was assessed using the Expanded Experimental Design Ability Test (E-EDAT). This test is reported to be content and terminology independent, making it suitable for this study. Two homomorphic questions were used as pre- and post- assessments. Two people assessed student responses using the rubric associated with the E-EDAT. A Pearson’s correlation showed a 74% correlation between the two raters for the pretest and an 82% correlation between the two raters for the posttest. The learning gains for the E-EDAT for students taught in everyday language were greater (mean 3.6) compared with students taught using scientific terminology (mean 2.0) using a t-test (p, “Active learning” can include low-stakes problem-solving exercises to illustrate and/or reinforce concepts. Previous studies investigating similar approaches have repeatedly shown improved short-term and long-term retention. We instituted active learning, including individual and group problem-solving, mini-projects undertaken outside of class, and short quizzes in class and/or online, in fall 2011 in a junior-level undergraduate microbiology class for molecular biosciences (biochemistry/biophysics, genetics and cell biology, and microbiology) majors and pre-professional students. Active learning was worth 8% of the course grade. We hypothesized that active learning would improve grades in our course, and that greater concept retention would improve grades in subsequent microbiology coursework. “Control” groups included students enrolled from fall 2009 to spring 2011, and “experimental” groups included students enrolled from fall 2011 to the present. Among microbiology majors, course grades improved (2.50 vs. 2.12 on a 4-point scale), and the rate of student failure (grades of C- and below) decreased (26% [n=31] vs. 36% [n=33]). Variability was observed in later coursework, with improvements in medical microbiology (2.98 vs. 2.59) but declines in immunology and microbial physiology (2.74 vs. 2.99 and 2.7 vs. 3.17, respectively). Average grades for the four courses analyzed improved after active learning (2.69 vs. 2.40). To improve statistical power and to gain better insight into learning outcomes, we are currently comparing course grades among all molecular biosciences majors. Our results have implications for the use and potential improvement of active learning exercises within our course and may inform us about longer-term outcomes for students in our undergraduate degree programs. ASM Curriculum Guideline Concept(s): Advancing STEM education and research Pedagogical Category(ies): Teaching approaches, Recognizing the importance of introducing research experiences throughout the undergraduate curriculum, the Boston College Biology Department designed an introductory laboratory course that immerses students in a semester-long research investigation in functional genomics. Rather than using the traditional format that pairs one-credit laboratory courses with lecture courses, the class adopted the format of an advanced lab course, meeting twice weekly for three hours. We hypothesized that the course would improve students’ understanding of core biological concepts and research methods skills, including the ability to design experiments, find information in online databases, understand the primary literature, and effectively communicate experimental results. We also hypothesized that student-generated results could add to the science knowledge base. For their project, students study the conservation of the enzymes involved in methionine biosynthesis between Saccharomyces cerevisiae and Schizosaccharomyces pombe, members of the Ascomycota separated from a common ancestor by ∼1 billion years. Student learning is assessed with lab notebooks, prelab quizzes, oral and poster presentations, database assignments, and five “micro-reports” that are compiled into a final report written in the style of a scientific publication. Students also perform an in-depth study of a research publication broken into segments, using a modification of the CREATE process. Pretest/posttest analyses indicated statistically and practically significant growth in both objectively-measured content knowledge and self-reported research methods skills. Student research results have also demonstrated the functional conservation of several enzymes involved in sulfur assimilation between S. cerevisiae and S. pombe. These scientific results are being prepared for a research publication. ASM Curriculum Guideline Concept(s): Evolution, Pathways Pedagogical Category(ies): Course design, This study details the assessment of a novel, year-long, research-based, major core laboratory curriculum completed by biology majors at Pace and LaSalle Universities during the 2013–2014 academic year. In the first semester, students conducted and analyzed microarray data to study the effects of osmotic stress on the yeast transcriptome. Students generated hypotheses on the roles of various affected genes. The following semester, students cloned candidate genes and designed and conducted cell-based functional assays using knockout yeast and overexpression studies to test their original hypotheses. We hypothesized that the year-long program would enhance the students’ biological literacy skills and their aptitude and appreciation for the process and practice of science. To assess this, we administered two validated concept inventories (CI) in a pre- and posttest format. We compared student performance on the CI to the course grades the students earned. Next, the students took the ETS Major Field Test in Biology (MFT). The scores earned on the MFT were compared between students that had and had not taken the year-long program. Finally, the students participated in the classroom undergraduate research experience (CURE) survey to help us determine their perceptions of the impact of the program on their interest/aptitude for research. The CI/course grade analysis showed that the “weaker” students in the first semester made the greatest gains on the CI. They also performed just as well as the “stronger” students on the assignments in the second semester (n=16). The MFT results indicated that the difference between the molecular biology/molecular genetics assessment indicator (AI) score approached significance (p=0.0556, U=13.5, n=9) where the students who took the year-long program performed better. Of the 22 questions about science on the CURE survey, the students indicated improved, statistically significant attitudes on 16 questions. These findings suggest that the program had several positive impacts on the students and we are hopeful that these observations will be strengthened upon inclusion of our 2014–2015 data. ASM Curriculum Guideline Concept(s): Advancing STEM education and research Pedagogical Category(ies): Hands-on projects, Student learning, The American Association for the Advancement of Science report Vision and Change in Undergraduate Biology Education: A Call to Action outlined a set of core competencies and skills for the undergraduate biology curriculum, with an emphasis on student-centered learning. This study examines the early alignment efforts of a traditional biology department (41 full-time faculty, 1200 majors) at a mid-sized undergraduate institution (20,500 students). Change was driven by institutional support and external accreditation processes. A mixed method approach was used to evaluate student outcomes with respect to Vision and Change core concepts and competencies, employing summative assessment tools at programmatic milestones. Preliminary analysis examined data collected over three years. Most student learning outcomes showed modest learning gains for core concepts (0.02–0.25, n=299) during a three-course introductory sequence as determined by a validated biology concept inventory administered to three cohorts. One cohort of graduating seniors (n=117) also completed the Major Fields Test on a voluntary basis; the mean percent correct for areas overlapping with Vision and Change core concepts ranged from 29% to 51%. In addition, capstone research projects and presentations for six cohorts were evaluated using a tool that covered five of the six Vision and Change competency areas; aggregate scores ranged from 3.1 to 3.6 on a scale of 1 (novice) to 4 (mastery). Overall, the alignment and evaluation processes provided a baseline for moving forward and highlighted areas for improvement in the curriculum, evaluation plan, and assessment tools. ASM Curriculum Guideline Concept(s): Advancing STEM education and research Pedagogical Category(ies): Student learning, Previous studies show many students have misconceptions regarding key molecular biology concepts. To achieve better student learning and retention, in-class collaborative activities might be a way to improve student understanding of a difficult yet fundamental molecular biology concept. We hypothesize collaborative learning activities may improve the common misconception regarding the concept that, “information in a gene directs expression of a specific protein.” To test this, the specific concept was taught in both a traditional lecture class and a collaborative learning activity-based class where small groups of students worked on five instructor-developed critical thinking activities relevant to the concept. The activities were designed for students to apply the concept they read in the assigned pre-reading. The students worked together to complete each specific activity and the instructor went over the activity in class and provided answers. Student learning was assessed using eight pre-/postquiz questions, an embedded four-part final exam question, and eight student interviews. A two-sample test was used to statistically compare results from the pre-/postquizzes and final exam. The proportion of students who correctly answered the questions on the postquiz from the collaborative learning class was higher than the traditional class in five of the eight questions, but these results were not statistically significant (p>0.05). The average learning gains from the collaborative learning class (56.74±4.46) were higher than the traditional class (45.25±8.17), but the difference was not statistically significant (p>0.05). The collaborative learning class had a statistically significant higher average score in two of the four parts of the embedded final exam question (p, The Small World Initiative (SWI), founded in 2013 by Jo Handelsman at Yale University, provides an exciting model for reforming the introductory biology laboratory by engaging students in an authentic, semester-long research project based on antibiotic discovery from soil bacteria. The research addresses the compelling global challenge of an inadequate pipeline of new antibiotics in the face of increasing antibiotic resistance among human pathogens. Our overarching goal in implementing this model at the University of Pittsburgh has been to transform the quality of the student experience in our very large introductory biology lab course by capturing the excitement of scientific discovery. We hypothesize that many students who do not persist in biology-related majors despite their strong interest in the field at college entry are driven away by an uninspiring curriculum, which they perceive as a lot of work without much reward. We further hypothesize that the authentic research experience exemplified by the Small World Initiative engages students to a high degree, leading to increased persistence by these students in science majors. We designed the course with emphasis on the development of students’ science process skills and have included features intended to bolster student ownership and drive student enthusiasm across the semester. The Project Ownership Survey (POS) developed by David Hanauer was administered to these students (n=13) and to students in a traditional, non research–based lab (n=33). Students rated their level of agreement with statements such as “My research will help solve a problem in the world,” “I had a personal reason for choosing the research project I worked on,” and “The word ‘happy’ describes my experience of the lab course.” We found a significant difference between students’ mean ratings, with Small World Initiative students rating their level of agreement with statements ∼70% higher than students in the traditional lab. We conclude that the Small World Initiative curriculum effectively promotes ownership and engagement. ASM Curriculum Guideline Concept(s): Impact of microorganisms, Advancing STEM education and research Pedagogical Category(ies): Course design, To enhance active learning, a guided enquiry–based lab was implemented in a microbiology course at Washington & Jefferson College. Over 10 weeks, students (n=20) characterized bacterial diversity using culture-dependent and culture-independent methods. Students crafted the study question, proposed a hypothesis, collected and analyzed data, and inferred conclusions. It was hypothesized that such a lab would improve students’ attitudes toward science and increase experimental design, data analysis, and scientific writing abilities. Experimental design ability was assessed using the Experimental Design Ability Test (EDAT; Sirum et al. 2013) administered at the beginning and end of the course. Mean EDAT scores significantly increased (pre-EDAT=3.7; post-EDAT=6.2; paired t-test, p=2.73×10−5). Ability to interpret data was assessed using Ability for Data Analysis Test (ADAT; Sirum et al. 2013) administered at the beginning and end of the course. Mean ADAT scores remained the same (pre-ADAT=4.15; post-ADAT=4.3; paired t-test, p=0.59). Data analysis ability was also assessed using an instructor-designed graph interpretation question. These scores also remained the same (pretest=66.7%; posttest=66.9%; paired t-test, p=0.98), showing no gain in data analysis ability. Students’ attitudes to science, open-ended labs, and scientific writing were surveyed before and at the end of the course with 22 questions based on the Likert scale. The survey showed that students’ confidence in executing biology lab-based tasks increased modestly (pretest=3.65; posttest=4; paired t-test, p=0.02), whereas attitudes toward science remained the same (pre-test=3.61; posttest=3.42; paired t-test, p=0.10). Affinity for open-ended labs increased (pretest=3.73; posttest=4.07; paired t-test, p=0.005) and confidence in scientific writing increased (pretest=2.9; posttest=3.9; paired t-test, p=0.0001). These data show increase in experimental design ability and improved confidence in science and scientific writing. They also reveal gaps in attitudes and competencies that should be considered for future iterations. ASM Curriculum Guideline Concept(s): Advancing STEM education and research Pedagogical Category(ies): Hands-on projects, Student learning, Although it is widely accepted that active-learning pedagogy bolsters student learning and engagement in college-level biology courses, little is known about how students perceive the academic rigor in these courses. As faculty strive to adopt active learning pedagogy while meeting institutional benchmarks associated with academic rigor, we ask what it means for a course to be “rigorous” from a student perspective? How do students define the attributes that make a learning experience “easy” or “hard”? To answer these questions, we administered an end-of-semester survey to 120 students enrolled in 100-and 300-level active-learning biology courses. Results from their open-ended responses were coded for patterns by two raters with established inter-rater reliability. We compared distributions between the courses using Chi-square and discovered that students perceived active-learning classes as both “hard” and “easy” due to increased cognitive demand coupled with peer and instructor support. Students defined active-learning courses as easy due to the format of the learning (e.g., workload seems manageable, content is logical and easy to follow, strong alignment between instruction and assessment, and high degree of faculty support). Simultaneously, students defined active learning as hard because they may not have entered the course with appropriate background knowledge and/or skills, and they find the cognitive demands of these courses to be difficult; patterns did not differ among courses (Chi-square, p=0.5, Cramer’s V=0.116). Results show that active-learning courses, although often perceived and communicated as “easy” by students, are also seen as academically rigorous due to increased cognitive demand. Students recognize they are being asked to do more higher-order thinking, yet find the intrinsically student-centered nature of active learning helps them overcome the challenges associated with course difficulty. These findings highlight the importance of being aware of and responding to student perceptions of academic rigor as we continue to implement national calls for reform in undergraduate biology. ASM Curriculum Guideline Concept(s): Advancing STEM education and research Pedagogical Category(ies): Student learning, Students come to college with a significant amount of prior knowledge which often includes misconceptions that hinder their ability to learn correct concepts in STEM disciplines. Misconceptions, or “alternative beliefs” amongst students have been widely studied in the literature (Nakhleh 1992; Kind 2004) and it is observed that when they are challenged directly and students are provided with opportunities to re-construct their worldview, the proportion of students able to use scientific concepts increases significantly (Fisher and Wandersee 2001), indicating that clearing misconceptions early on is crucial to student learning. Our study aims to identify and resolve misconceptions in three important gateway STEM courses by using student reflective activities and guided-inquiry learning. Faculty members teaching three STEM courses, Biology, Chemistry, and Mathematics, are working to identify and address common misconceptions that prevent students from being successful in these courses. These are gateway courses with considerably high attrition rates. To enhance conceptual understanding and the learning process, instructors conduct reflection sessions outside classroom instruction to specifically address students’ alternative beliefs in order to foster conceptual understanding of course material rather than rote memorization. During pilot implementation last semester (fall 2014), students reflected on their own prior knowledge and belief systems and worked with peers to discover the correct concepts. They analyzed each other’s erroneous beliefs and, in the process, recognized and corrected their misconceptions. We saw a marginal difference between experimental and control groups last semester. However, we are redesigning and refining the intervention sessions of reflections, the exam wrappers, and the study skills/attitude surveys this semester to collect more meaningful data to assess whether resolving misconceptions early on will increase conceptual understanding in community college students. ASM Curriculum Guideline Concept(s): Advancing STEM education and research Pedagogical Category(ies): Student learning, Teaching approaches, Teaching tools, As the United States becomes an increasingly diverse society, it is essential that students be provided with role models that include minorities. To that end, we are continuing a project to develop and test inquiry-based approaches for undergraduates that focus on the life and work of minority scientists who have made significant contributions to the field of biology. Our efforts have most recently concentrated on Lydia Villa-Komaroff, a pioneering Hispanic biotechnologist. In 1978, she led the research team that first transformed bacteria to produce human insulin. We hypothesized that the use of these activities would increase the students’ appreciation for this scientist’s work as well as improve their comprehension of the science behind the discoveries that she made. Exercises were developed for a General Microbiology and a nonmajors Biology course. Student teams in both courses employed an inquiry-based, collaborative approach whereby they constructed a timeline of Villa-Komaroff’s life and career using references provided by the instructor. Students in the General Microbiology course subsequently conducted a transformation lab exercise using procedures similar to those developed by Villa-Komaroff and her colleagues. The nonmajors biology students extracted DNA from eukaryotic cells to model the first steps that Villa-Komaroff’s team took to transform the bacteria. A pre- and posttest, designed to measure the students’ comprehension of basic concepts important to the project as well as overall course goals, was given to students in both courses. Comparisons of pre- and posttests given to students in the General Microbiology course showed that test scores improved from a mean of 42% on the pretest to 58% on the posttest. Test results for the nonmajors biology course improved from a mean of 40% on the pretest to 59% on the posttest. In conclusion, this approach is a viable, inquiry-based alternative to traditional methods of teaching to help undergraduates understand the important contributions minority scientists have made to the field of biology. ASM Curriculum Guideline Concept(s): Information flow, Advancing STEM education and research Pedagogical Category(ies): Hands-on projects, The economic changes that have taken place worldwide have created a high demand for college graduates in the fields of science, technology, engineering, and mathematics, also collectively known as STEM. This increased demand has led to numerous think tanks, policies, and programs investigating how these numbers can be increased across all disciplines in STEM. One of the overwhelming findings is that the STEM fields lack diversity. Statistics show that the number of Blacks earning bachelor’s degrees in STEM fields has increased, but at a slower pace than in non-STEM fields (NSF, 2011). The hypothesis for this study is that creation of an organization that encourages and provides academic and professional support for basic science research along with mentoring will help black males develop the desire to matriculate through undergraduate and graduate degrees in STEM fields. Black male students in STEM fields met at least once a month outside of regular class meetings to discuss academics, pitfalls, and also any concerns with their progress in their field of study. In addition to monthly meetings, students were voluntarily asked to complete a Students Individual Development Plan (IDP), which asks the student to target new goals and expectations. To track progress of implementation of this plan, grades were calculated and tracked at the end of each semester and compared with other disciplines outside of STEM. The data showed a significant increase (p, This study examined the efficacy of project-based learning (PTBL) in an undergraduate neurobiology course to improve attitudes and increase confidence toward neuroscience content and improve critical thinking skills. Students are often interested in learning about diseased states of the nervous system but can be discouraged by having to learn the chemical and cellular mechanisms underlying the pathologies. Thus, it can be a challenge to provide students with significant learning experiences that they are excited about. I hypothesized that PTBL would 1) improve critical and integrative thinking skills; 2) build confidence in understanding neuroscience and promote positive attitudes toward neuroscience; and 3) increase understanding of neuroscience concepts. To test these hypotheses, students were grouped into teams and completed three substantial projects consisting of team-authored research papers and poster presentations. Rubrics measured learning gains in ability to address specific project goals (Goals), provide evidence from a variety of valid resources (Resources), make logical, supported statements (Thinking), and analyze and synthesize ideas and concepts (Integration). Preand postsurveys assessed attitudes toward neuroscience, teams and projects, and understanding of neuroscience concepts. Pre- and posttests measured knowledge of neuroscience content. Analysis of papers revealed significant increases in research, thinking, and integrative skills (p< 0.05). By the end of the course, students reported significantly higher confidence in neuroscience knowledge (p=0.004). However, there was no change in attitudes toward neuroscience, working in a team or on projects. Students answered more questions correctly on the neuroscience content posttest than the pretest (p=0.036), and, as student attitudes toward neuroscience improved, so did their ability to correctly answer content questions (p=0.013). PTBL is an effective tool that educators can use to actively engage students while enhancing critical thinking skills and content knowledge in undergraduate biology courses. ASM Curriculum Guideline Concept(s): Advancing STEM education and research Pedagogical Category(ies): Hands-on projects
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- 2015
44. Comparison of Methods for Analysis of Clinical [11C]Raclopride Studies
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Lammertsma, A. A., Bench, C. J., Hume, S. P., Osman, S., Gunn*, K., Brooks, D. J., and Frackowiak, R.S. J.
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- 1996
45. Vox Sanguinis International Forum on the use of prehospital blood products and pharmaceuticals in the treatment of patients with traumatic hemorrhage
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Yazer, M. H., Spinella, P. C., Allard, S., Roxby, D., So-Osman, C., Lozano, M., Gunn, K., Shih, A. W., Stensballe, J., Johansson, P. I., Hansen, M. Bagge, Maegele, M., Doughty, H., Crombie, N., Jenkins, D. H., McGinity, A. C., Schaefer, R. M., Martinaud, C., Shinar, E., Strugo, R., Chen, J., Russcher, H., Yazer, M. H., Spinella, P. C., Allard, S., Roxby, D., So-Osman, C., Lozano, M., Gunn, K., Shih, A. W., Stensballe, J., Johansson, P. I., Hansen, M. Bagge, Maegele, M., Doughty, H., Crombie, N., Jenkins, D. H., McGinity, A. C., Schaefer, R. M., Martinaud, C., Shinar, E., Strugo, R., Chen, J., and Russcher, H.
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- 2018
46. Deep survey sources, and predictions for XMM and AXAF
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Griffiths, R.E., Ptak, A., Boyle, B.J., Shanks, T., Stewart, G.C., Georgantopoulos, I., Gunn, K., Almaini, O., and Blair, A.
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- 2000
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47. Vox Sanguinis International Forum on the use of prehospital blood products and pharmaceuticals in the treatment of patients with traumatic hemorrhage
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Yazer, M. H., primary, Spinella, P. C., additional, Allard, S., additional, Roxby, D., additional, So-Osman, C., additional, Lozano, M., additional, Gunn, K., additional, Shih, A. W., additional, Stensballe, J., additional, Johansson, P. I., additional, Bagge Hansen, M., additional, Maegele, M., additional, Doughty, H., additional, Crombie, N., additional, Jenkins, D. H., additional, McGinity, A. C., additional, Schaefer, R. M., additional, Martinaud, C., additional, Shinar, E., additional, Strugo, R., additional, Chen, J., additional, and Russcher, H., additional
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- 2018
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48. Calibrated Seismic Imaging of Eddy‐Dominated Warm‐Water Transport Across the Bellingshausen Sea, Southern Ocean
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Gunn, K. L., primary, White, N. J., additional, Larter, R. D., additional, and Caulfield, C. P., additional
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- 2018
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49. ON THE CONCENTRATION OF ACETIC ACID IN STRAW AND SOIL
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LYNCH, J. M., GUNN, K. B., and PANTING, LYNDA M.
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- 1980
50. THE EFFECT OF CHELATING AGENTS ON THE ABSORPTION OF RADIUM BY PLANTS
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GUNN, K. B. and MISTRY, K. B.
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- 1970
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