826 research outputs found
Awareness without learning: A preliminary study exploring the effects of beachgoer's experiences on risk taking behaviours
Most drowning deaths on Australian beaches occur in locations not patrolled by lifeguards. At patrolled locations, where lifeguards supervise flagged areas in which beachgoers are encouraged to swim between, the incidence of drowning is reduced. To date, risk prevention practices on coasts focus on patrolled beaches, deploying warning signs at unpatrolled locations with the aim of raising public awareness of risk. What remains unexplored is the potential for learning and behaviour change that can transfer from patrolled to unpatrolled beaches through beachgoer's experiences and interactions with lifeguards. The aim of this preliminary study is to explore the risk perceptions of beachgoers at a patrolled beach to establish if and how their experiences of beach risk and interactions with lifeguards affect their behaviours. Data was collected in Gerroa, Australia by engaging 49 beachgoers using a mixed survey-interview methodology. Results show that beachgoers are aware that they should ‘swim between the flags’, but many did not know the basis for the positioning of safety flags. A key finding is that beachgoer's express a clear desire for a skills-based model of community engagement that enables learning with lifeguards. This demonstrates a reflective public that desires skill-development, which may transfer from patrolled to unpatrolled beaches to affect broader risk reduction on the Australian coast. Learning how to avoid site-specific rip hazards with lifeguards at the beach presents a promising, and previously unexplored model for beach drowning risk prevention that has the potential to affect behaviour at unpatrolled beaches, providing an empirically-supported alternative to prevailing deficit-based awareness raising methods
Interactions between magnetohydrodynamic shear instabilities and convective flows in the solar interior
Motivated by the interface model for the solar dynamo, this paper explores
the complex magnetohydrodynamic interactions between convective flows and
shear-driven instabilities. Initially, we consider the dynamics of a forced
shear flow across a convectively-stable polytropic layer, in the presence of a
vertical magnetic field. When the imposed magnetic field is weak, the dynamics
are dominated by a shear flow (Kelvin-Helmholtz type) instability. For stronger
fields, a magnetic buoyancy instability is preferred. If this stably stratified
shear layer lies below a convectively unstable region, these two regions can
interact. Once again, when the imposed field is very weak, the dynamical
effects of the magnetic field are negligible and the interactions between the
shear layer and the convective layer are relatively minor. However, if the
magnetic field is strong enough to favour magnetic buoyancy instabilities in
the shear layer, extended magnetic flux concentrations form and rise into the
convective layer. These magnetic structures have a highly disruptive effect
upon the convective motions in the upper layer.Comment: 11 pages, 10 figures, accepted for publication in MNRA
On-chip manipulation of single photons from a diamond defect
Operating reconfigurable quantum circuits with single photon sources is a key goal of photonic quantum information science and technology. We use an integrated waveguide device containing directional couplers and a reconfigurable thermal phase controller to manipulate single photons emitted from a chromium related color center in diamond. Observation of both a wavelike interference pattern and particlelike sub-Poissionian autocorrelation functions demonstrates coherent manipulation of single photons emitted from the chromium related center and verifies wave particle duality. © 2013 American Physical Society
Neoliberalisation and 'lad cultures' in higher education
This paper links HE neoliberalisation and ‘lad cultures’, drawing on interviews and focus groups with women students. We argue that retro-sexist ‘laddish’ forms of masculine competitiveness and misogyny have been reshaped by neoliberal rationalities to become modes of consumerist sexualised audit. We also suggest that neoliberal frameworks scaffold an individualistic and adversarial culture among young people that interacts with perceived threats to men’s privilege and intensifies attempts to put women in their place through misogyny and sexual harassment. Furthermore, ‘lad cultures’, sexism and sexual harassment in higher education may be invisibilised by institutions to preserve marketability in a neoliberal context. In response, we ask if we might foster dialogue and partnership between feminist and anti-marketisation politics
Escherichia coli induces apoptosis and proliferation of mammary cells
Mammary cell apoptosis and proliferation were assessed after injection of Escherichia coli into the left mammary quarters of six cows. Bacteriological analysis of foremilk samples revealed coliform infection in the injected quarters of four cows. Milk somatic cell counts increased in these quarters and peaked at 24 h after bacterial injection. Body temperature also increased, peaking at 12 h postinjection, The number of apoptotic cells was significantly higher in the mastitic tissue than in the uninfected control. Expression of Bax and interleukin-1 beta converting enzyme increased in the mastitic tissue at 24 h and 72 h postinfection, whereas Bcl-2 expression decreased at 24 h but did not differ significantly from the control at 72 h postinfection, Induction of matrix metalloproteinase-g, stromelysin-1 and urokinase-type plasminogen activator was also observed in the mastitic tissue. Moreover, cell proliferation increased in the infected tissue, These results demonstrate that Escherichia coli-induced mastitis promotes apoptosis and cell proliferation
Interfaces: The Next NDE Challenge
Nondestructive evaluation, as practiced in the 1960’s, attempted to detect (but was often unable to characterize) the existence of defects in engineering structures. Qualitative criteria were used in the assessment of defect significance and the determination of accept/reject decisions. Advances in elasto-plastic fracture mechanics during the 1970’s focused attention upon the defect size and orientation- if these could be measured, then fracture mechanics was capable of quantitative structural integrity evaluation. The papers presented in this conference series during the 1980’s trace the considerable advances of quantitative nondestructive evaluation in satisfying this measurement need. Nowadays, for monolithic materials with well defined fracture toughness, the overconservative rejection criteria of the past are beginning to be replaced by “retirement for cause” concepts
Bedside Interactions from the Other Side of the Bedrail
To assess the importance to patients of various aspects of bedside interactions with physician teams. Design : Cross-sectional survey. Setting : VA hospital. Patients : Ninety-seven medical inpatients. Intervention : Survey of 44 questions including short answer, multiple choice, and Likert-type questions. Measurements and Main Results : Data analysis included descriptive statistics. The sample was predominantly male, with a mean age of 62. Overall satisfaction with the hospital experience and with the team of doctors were both high (95% and 96% reported being very or mostly satisfied, respectively). Patients reported learning about several issues during their interactions with the teams; the 3 most highly rated areas were new problems, tests that will be done, and treatments that will be done. Most patients (76%) felt that their teams cared about them very much. Patients were made comfortable when the team showed that they cared, listened, and appeared relaxed (reported by 63%, 57%, and 54%, respectively). Patients were made uncomfortable by the team using language they did not understand (22%) and when several people examined them at once (13%). Many (58%) patients felt personally involved in teaching. The majority of patients liked having medical students and residents involved in their care (69% and 64%, respectively). Conclusions : Patients have much to teach about what is important about interacting with physician teams. Although patients' reactions to team interactions are generally positive, patients are different with respect to what makes them comfortable and uncomfortable. Taking their preferences into account could improve the experience of being in a teaching hospital.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75456/1/j.1525-1497.2005.40192.x.pd
Cold gas accretion in galaxies
Evidence for the accretion of cold gas in galaxies has been rapidly
accumulating in the past years. HI observations of galaxies and their
environment have brought to light new facts and phenomena which are evidence of
ongoing or recent accretion:
1) A large number of galaxies are accompanied by gas-rich dwarfs or are
surrounded by HI cloud complexes, tails and filaments. It may be regarded as
direct evidence of cold gas accretion in the local universe. It is probably the
same kind of phenomenon of material infall as the stellar streams observed in
the halos of our galaxy and M31. 2) Considerable amounts of extra-planar HI
have been found in nearby spiral galaxies. While a large fraction of this gas
is produced by galactic fountains, it is likely that a part of it is of
extragalactic origin. 3) Spirals are known to have extended and warped outer
layers of HI. It is not clear how these have formed, and how and for how long
the warps can be sustained. Gas infall has been proposed as the origin. 4) The
majority of galactic disks are lopsided in their morphology as well as in their
kinematics. Also here recent accretion has been advocated as a possible cause.
In our view, accretion takes place both through the arrival and merging of
gas-rich satellites and through gas infall from the intergalactic medium (IGM).
The infall may have observable effects on the disk such as bursts of star
formation and lopsidedness. We infer a mean ``visible'' accretion rate of cold
gas in galaxies of at least 0.2 Msol/yr. In order to reach the accretion rates
needed to sustain the observed star formation (~1 Msol/yr), additional infall
of large amounts of gas from the IGM seems to be required.Comment: To appear in Astronomy & Astrophysics Reviews. 34 pages.
Full-resolution version available at
http://www.astron.nl/~oosterlo/accretionRevie
The Classification of T Dwarfs
We discuss methods for classifying T dwarfs based on spectral morphological
features and indices. T dwarfs are brown dwarfs which exhibit methane
absorption bands at 1.6 and 2.2 . Spectra at red optical (6300--10100
{\AA}) and near-infrared (1--2.5 ) wavelengths are presented, and
differences between objects are noted and discussed. Spectral indices useful
for classification schemes are presented. We conclude that near-infrared
spectral classification is generally preferable for these cool objects, with
data sufficient to resolve the 1.17 and 1.25 K I doublets lines being
most valuable. Spectral features sensitive to gravity are discussed, with the
strength of the K-band peak used as an example. Such features may be used to
derive a two-dimensional scheme based on temperature and mass, in analogy to
the MK temperature and luminosity classes.Comment: 15 pages, 6 figures, conference proceedings for IAU Ultracool Dwarf
Stars session, ed. I. Steele & H. Jone
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