4,266 research outputs found
Understanding student satisfaction and dissatisfaction: An interpretive study in the UK Higher Education Context
This article represents a cross-sectional study of undergraduate students across two North West University Business Schools in the UK. A purposefully designed questionnaire was collected from 350 students. The student experience was described in the form of hand written narratives by first and final year students and had been identified by the respondents themselves as being satisfying or dissatisfying with the areas of teaching and learning and the supporting service environment. The study also assessed whether their experiences were likely to influence their loyalty behaviours with respect to remaining on their chosen course of study; recommending the university; and continuing at a higher level of study. The data was captured and analysed using the qualitative critical incident technique to capture the voice of the student and identified the critical determinants of quality within Higher Education, i.e. those areas that would influence loyalty behaviour, as being Access; Attentiveness; Availability; and Communication. A number of new determinants of quality have been identified out of the research by three independent judges, namely motivation, reward, social inclusion, usefulness, value for money and fellow student behaviour
Hydrogen contamination in Ge-doped SiO[sub 2] thin films prepared by helicon activated reactive evaporation
Germanium-doped silicon oxidethin films were deposited at low temperature by using an improved helicon plasma assisted reactive evaporation technique. The origins of hydrogen contamination in the film were investigated, and were found to be H incorporation during deposition and postdeposition water absorption. The H incorporation during deposition was avoided by using an effective method to eliminate the residual hydrogen present in the depositionsystem. The microstructure, chemical bonds, chemical etch rate, and optical index of the films were studied as a function of the deposition conditions. Granular microstructures were observed in low-density films, and were found to be the cause of postdeposition water absorption. The granular microstructure was eliminated and the film was densified by increasing the helicon plasma power and substrate bias during deposition. A high-density film was shown to have no postdeposition water absorption and no OH detected by using a Fourier-transform infrared spectrometer
Leishmania (Viannia) spp. dissemination and tissue tropism in naturally infected dogs (Canis familiaris).
First evidence is presented for Leishmania (Viannia) spp. dissemination and tissue tropism in the domestic dog. Using PCR and histology, parasites were detected in the conjunctiva, lung, lymph nodes and ovaries of 2 naturally infected Peruvian dogs. The detection of parasites in the blood indicates that parasite dissemination to those organs may have been haematogenous
The Crystal Structure of Human Tyrosyl-DNA Phosphodiesterase, Tdp1
AbstractTyrosyl-DNA phosphodiesterase (Tdp1) catalyzes the hydrolysis of a phosphodiester bond between a tyrosine residue and a DNA 3′ phosphate. The enzyme appears to be responsible for repairing the unique protein-DNA linkage that occurs when eukaryotic topoisomerase I becomes stalled on the DNA in the cell. The 1.69 Å crystal structure reveals that human Tdp1 is a monomer composed of two similar domains that are related by a pseudo-2-fold axis of symmetry. Each domain contributes conserved histidine, lysine, and asparagine residues to form a single active site. The structure of Tdp1 confirms that the protein has many similarities to the members of the phospholipase D (PLD) superfamily and indicates a similar catalytic mechanism. The structure also suggests how the unusual protein-DNA substrate binds and provides insights about the nature of the substrate in vivo
Commonsense Metaphysics and Lexical Semantics
In the TACITUS project for using commonsense knowledge in the understanding of texts about mechanical devices and their failures, we have been developing various commonsense theories that are needed to mediate between the way we talk about the behavior of such devices and causal models of their operation. Of central importance in this effort is the axiomatization of what might be called commonsense metaphysics. This includes a number of areas that figure in virtually every domain of discourse, such as granularity, scales, time, space, material, physical objects, shape, causality, functionality, and force. Our effort has been to construct core theories of each of these areas, and then to define, or at least characterize, a large number of lexical items in terms provided by the core theories. In this paper we discuss our methodological principles and describe the key ideas in the various domains we are investigating
Structure and physical properties of GexAsySe1−x−y glasses with the same mean coordination number of 2.5
We have prepared and analyzed five different compositions of GexAsySe1−x−yglasses that have the same mean coordination number (MCN) of 2.5 in order to understand whether MCN or chemical composition has the dominant effect on the physical properties of the glass. Density measurements showed a maximum for the chemically stoichiometric Ge12.5As25Se62.5 sample and suggested that some rearrangement of the atoms was occurring as one atom substituted for another. The measurements of Tg, however, showed that the glasses had almost same glass transition temperature and suggested that the glassnetwork connectivity did not change much with composition. Although Raman scattering and x-ray photoelectron spectra of the glasses indicate that the percentage of the different structural units changes with the composition, there was no evidence of the existence of structural units that could change the overall connectivity of the glassnetwork. Therefore, we concluded that glasses with same MCN but different composition have similar glassnetwork connectivity, and that chemical composition has only a secondary effect on the physical properties of the glasses.This research was partly supported by the Australian Research
Council through its Centres of Excellence and Discovery
DP110102753 programs
A New Spin on Galactic Dust
We present a new puzzle involving Galactic microwave emission and attempt to
resolve it. On one hand, a cross-correlation analysis of the WHAM H-alpha map
with the Tenerife 10 and 15 GHz maps shows that the well-known DIRBE correlated
microwave emission cannot be dominated by free-free emission. On the other
hand, recent high resolution observations in the 8-10 GHz range with the Green
Bank 140 ft telescope by Finkbeiner et al. failed to find the corresponding 8
sigma signal that would be expected in the simplest spinning dust models. So
what physical mechanism is causing this ubiquitous dust-correlated emission? We
argue for a model predicting that spinning dust is the culprit after all, but
that the corresponding small grains are well correlated with the larger grains
seen at 100 micron only on large angular scales. In support of this grain
segregation model, we find the best spinning dust template to involve higher
frequency maps in the range 12-60 micron, where emission from transiently
heated small grains is important. Upcoming CMB experiments such as ground-based
interferometers, MAP and Planck LFI with high resolution at low frequencies
should allow a definitive test of this model.Comment: Minor revisions to match accepted ApJ version. 6 pages, 4 figs. Color
figures and more foreground information at
http://www.hep.upenn.edu/~angelica/foreground.html#spin or from
[email protected]
A 4.8- and 8.6-GHz Survey of the Large Magellanic Cloud: I The Images
Detailed 4.8- and 8.6-GHz radio images of the entire Large Magellanic Cloud
with half-power beamwidths of 33" at 4.8 GHz and 20" at 8.6 GHz have been
obtained using the Australia Telescope Compact Array. A total of 7085 mosaic
positions were used to cover an area of 6 degrees on a side. Full polarimetric
observations were made. These images have sufficient spatial resolution (~8 and
5 pc, respectively) and sensitivity (3-sigma of 1 mJy/beam) to identify most of
the individual SNRs and H II regions and also, in combination with available
data from the Parkes 64-m telescope, the structure of the smooth emission in
that galaxy. In addition, limited data using the sixth antenna at 4.5 to 6-km
baselines are available to distinguish bright point sources (<3 and 2 arcsec,
respectively) and to help estimate sizes of individual sources smaller than the
resolution of the full survey. The resultant database will be valuable for
statistical studies and comparisons with x-ray, optical and infrared surveys of
the LMC with similar resolution.Comment: 28 pages, 10 figures, 2 tables, accepted for publication in the Feb
2005 A
Large Scale Structure traced by Molecular Gas at High Redshift
We present observations of redshifted CO(1-0) and CO(2-1) in a field
containing an overdensity of Lyman break galaxies (LBGs) at z=5.12. Our
Australia Telescope Compact Array observations were centered between two
spectroscopically-confirmed z=5.12 galaxies. We place upper limits on the
molecular gas masses in these two galaxies of M(H_2) <1.7 x 10^10 M_sun and
<2.9 x 10^9 M_sun (2 sigma), comparable to their stellar masses. We detect an
optically-faint line emitter situated between the two LBGs which we identify as
warm molecular gas at z=5.1245 +/- 0.0001. This source, detected in the CO(2-1)
transition but undetected in CO(1-0), has an integrated line flux of 0.106 +/-
0.012 Jy km/s, yielding an inferred gas mass M(H_2)=(1.9 +/- 0.2) x 10^10
M_sun. Molecular line emitters without detectable counterparts at optical and
infrared wavelengths may be crucial tracers of structure and mass at high
redshift.Comment: 4 pages, accepted for publication in ApJ Letter
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