1,275 research outputs found
Engaging students in bioscience research to improve their learning experience
Combining teaching and research is the definitive principle of ‘research-informed teaching’ (RIT) (Healey, 2005). RIT is pivotal for improving the student learning experience. All undergraduate students within the School of Science and Engineering, Teesside University (TU), can become RIT co-creators via their curricula-based Level 5 project proposal module and Level 6 research project. This case study illustrates how the authors used complementary, co-curricula methods to enhance student engagement with bioscience research utilising co-designed research projects and publication preparation. The success of student involvement in these initiatives was measured against six key personal attributes (Adaptable, Articulate, Aspiring, Creative, Critical, Confident), questionnaire responses from ten respondents, and a summary of tangible research outputs. An evaluation of staff involvement was made with semi-structured interviews. Overall, the research-led, partnership approach resulted in increased student motivation, aspiration and confidence in their further learning and employment
Thermal Evolution and Light Curves of Young Bare Strange Stars
The cooling of a young bare strange star is studied numerically by solving
the equations of energy conservation and heat transport for both normal and
superconducting strange quark matter inside the star. We show that the thermal
luminosity from the strange star surface, due to both photon emission and e+e-
pair production, may be orders of magnitude higher than the Eddington limit,
for about one day for normal quark matter but possibly for up to a hundred
years for superconducting quark matter, while the maximum of the photon
spectrum is in hard X-rays with a mean energy of ~ 100 keV or even more. This
differs both qualitatively and quantitatively from the photon emission from
young neutron stars and provides a definite observational signature for bare
strange stars. It is shown that the energy gap of superconducting strange quark
matter may be estimated from the light curves if it is in the range from ~ 0.5
MeV to a few MeV.Comment: Ref [10] added and abstract shortened. 4 pages, 3 figures, revtex4.
To be published in Phys. Rev. Letter
The -structures on complex line bundles and explicit Riemannian metrics with SU(4)-holonomy
We completely explore the system of ODE's which is equivalent to the
existence of a parallel -structure on the cone over a 7-dimensional
3-Sasakian manifold. The one-dimensional family of solutions of this system is
constructed. The solutions of this family correspond to metrics with holonomy
SU(4) which generalize the Calabi metrics.Comment: 11 page
Are strange stars distinguishable from neutron stars by their cooling behaviour?
The general statement that strange stars cool more rapidly than neutron stars
is investigated in greater detail. It is found that the direct Urca process
could be forbidden not only in neutron stars but also in strange stars. If so,
strange stars would be slowly cooling and their surface temperatures would be
more or less indistinguishable from those of slowly cooling neutron stars. The
case of enhanced cooling is reinvestigated as well. It is found that strange
stars cool significantly more rapidly than neutron stars within the first years after birth. This feature could become particularly interesting if
continued observation of SN 1987A would reveal the temperature of the possibly
existing pulsar at its centre.Comment: 10 pages, 3 ps-figures, to appear in the proceedings of the
International Symposium on ''Strangeness in Quark Matter 1997``, April
14--18, Thera (Santorini), Hella
Entanglement, recoherence and information flow in an accelerated detector - quantum field system: Implications for black hole information issue
We study an exactly solvable model where an uniformly accelerated detector is
linearly coupled to a massless scalar field initially in the Minkowski vacuum.
Using the exact correlation functions we show that as soon as the coupling is
switched on one can see information flowing from the detector to the field and
propagating with the radiation into null infinity. By expressing the reduced
density matrix of the detector in terms of the two-point functions, we
calculate the purity function in the detector and study the evolution of
quantum entanglement between the detector and the field. Only in the ultraweak
coupling regime could some degree of recoherence in the detector appear at late
times, but never in full restoration. We explicitly show that under the most
general conditions the detector never recovers its quantum coherence and the
entanglement between the detector and the field remains large at late times. To
the extent this model can be used as an analog to the system of a black hole
interacting with a quantum field, our result seems to suggest in the prevalent
non-Markovian regime, assuming unitarity for the combined system, that black
hole information is not lost but transferred to the quantum field degrees of
freedom. Our combined system will evolve into a highly entangled state between
a remnant of large area (in Bekenstein's black hole atom analog) without any
information of its initial state, and the quantum field, now imbued with
complex information content not-so-easily retrievable by a local observer.Comment: 16 pages, 12 figures; minor change
Modern compact star observations and the quark matter equation of state
We present a hybrid equation of state (EoS) for dense matter that satisfies
phenomenological constraints from modern compact star (CS) observations which
indicate high maximum masses (M = 2 M_sun) and large radii (R> 12 km). The
corresponding isospin symmetric EoS is consistent with flow data analyses of
heavy-ion collisions and a deconfinement transition at approx. 0.55 fm^{-3}.
The quark matter phase is described by a 3-flavor Nambu--Jona-Lasinio model
that accounts for scalar diquark condensation and vector meson interactions
while the nuclear matter phase is obtained within the
Dirac-Brueckner-Hartree-Fock (DBHF) approach using the Bonn-A potential. We
demonstrate that both pure neutron stars and neutron stars with quark matter
cores (QCSs) are consistent with modern CS observations. Hybrid star
configurations with a CFL quark core are unstable.Comment: 16 pages, 4 figures; published version, important note added in proo
Bell Correlations and the Common Future
Reichenbach's principle states that in a causal structure, correlations of
classical information can stem from a common cause in the common past or a
direct influence from one of the events in correlation to the other. The
difficulty of explaining Bell correlations through a mechanism in that spirit
can be read as questioning either the principle or even its basis: causality.
In the former case, the principle can be replaced by its quantum version,
accepting as a common cause an entangled state, leaving the phenomenon as
mysterious as ever on the classical level (on which, after all, it occurs). If,
more radically, the causal structure is questioned in principle, closed
space-time curves may become possible that, as is argued in the present note,
can give rise to non-local correlations if to-be-correlated pieces of classical
information meet in the common future --- which they need to if the correlation
is to be detected in the first place. The result is a view resembling Brassard
and Raymond-Robichaud's parallel-lives variant of Hermann's and Everett's
relative-state formalism, avoiding "multiple realities."Comment: 8 pages, 5 figure
The Specific Heat of Normal, Degenerate Quark Matter: Non-Fermi Liquid Corrections
In normal degenerate quark matter, the exchange of dynamically screened
transverse gluons introduces infrared divergences in the quark self-energies
that lead to the breakdown of the Fermi liquid description. If the core of
neutron stars are composed of quark matter with a normal component, cooling by
direct quark Urca processes may be modified by non-Fermi liquid corrections. We
find that while the quasiparticle density of states is finite and non-zero at
the Fermi surface, its frequency derivative diverges and results in non-Fermi
liquid corrections to the specific heat of the normal, degenerate component of
quark matter. We study these non-perturbative non-Fermi liquid corrections to
the specific heat and the temperature dependence of the chemical potential and
show that these lead to a reduction of the specific heat.Comment: new discussion, updated references, accepted in PR
Eliciting a predatory response in the eastern corn snake (Pantherophis guttatus) using live and inanimate sensory stimuli: implications for managing invasive populations
North America's Eastern corn snake (Pantherophis guttatus) has been introduced to several islands throughout the Caribbean and Australasia where it poses a significant threat to native wildlife. Invasive snake control programs often involve trapping with live bait, a practice that, as well as being costly and labour intensive, raises welfare and ethical concerns. This study assessed corn snake response to live and inanimate sensory stimuli in an attempt to inform possible future trapping of the species and the development of alternative trap lures. We exposed nine individuals to sensory cues in the form of odour, visual, vibration and combined stimuli and measured the response (rate of tongue-flick [RTF]). RTF was significantly higher in odour and combined cues treatments, and there was no significant difference in RTF between live and inanimate cues during odour treatments. Our findings suggest chemical cues are of primary importance in initiating predation and that an inanimate odour stimulus, absent of simultaneous visual and vibratory cues, is a potential low-cost alternative trap lure for the control of invasive corn snake populations
Theoretical study of the insulating oxides and nitrides: SiO2, GeO2, Al2O3, Si3N4, and Ge3N4
An extensive theoretical study is performed for wide bandgap crystalline
oxides and nitrides, namely, SiO_{2}, GeO_{2}, Al_{2}O_{3}, Si_{3}N_{4}, and
Ge_{3}N_{4}. Their important polymorphs are considered which are for SiO_{2}:
-quartz, - and -cristobalite and stishovite, for
GeO_{2}: -quartz, and rutile, for Al_{2}O_{3}: -phase, for
Si_{3}N_{4} and Ge_{3}N_{4}: - and -phases. This work
constitutes a comprehensive account of both electronic structure and the
elastic properties of these important insulating oxides and nitrides obtained
with high accuracy based on density functional theory within the local density
approximation. Two different norm-conserving \textit{ab initio}
pseudopotentials have been tested which agree in all respects with the only
exception arising for the elastic properties of rutile GeO_{2}. The agreement
with experimental values, when available, are seen to be highly satisfactory.
The uniformity and the well convergence of this approach enables an unbiased
assessment of important physical parameters within each material and among
different insulating oxide and nitrides. The computed static electric
susceptibilities are observed to display a strong correlation with their mass
densities. There is a marked discrepancy between the considered oxides and
nitrides with the latter having sudden increase of density of states away from
the respective band edges. This is expected to give rise to excessive carrier
scattering which can practically preclude bulk impact ionization process in
Si_{3}N_{4} and Ge_{3}N_{4}.Comment: Published version, 10 pages, 8 figure
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