3,654 research outputs found
Evangelical Christians in Canadian National Television News, 1994–2004: A Frame Analysis
Recent surveys have shown that most evangelical Christians in Canada believe that the news media treat them unfairly. This study empirically tested the validity of the evangelicals’ charge against the media by examining the frames used in the nightly, national news reports of Global, CBC and CTV television networks. An analysis of all reports featuring evangelicals showed that neutral and positive frames, together, were almost equal in strength and number to negative frames used; this resulted in an overall rating of “balanced” for the coverage.
While overall the coverage was balanced, the frequency and exclusivity of certain negative frames elevated their saliency considerably. For example, the “evangelicals as intolerant” frame alone appeared in one quarter of all reports. Regarding topic of the news reports, evangelicals most often received coverage for involvement in politics followed closely by involvement in criminal or immoral actions. Implications of these results are discussed
Behaviour of dairy cows on organic and non-organic farms
There is an increasing number of organic dairy farms in the UK. The aim of this study is to compare behaviour of dairy cows on organic and non-organic farms. Twenty organic and 20 non-organic farms throughout the UK were visited over two winters (2004/05 and 2005/06). Organic and non-organic farms were paired for housing type, herd size, milk production traits and location. The number of cows feeding was counted every fifteen minutes for 4.5 h after new feed was available post morning milking. Behaviour at the feed-face was recorded for 60 minutes and aggressive interactions between cows were quantified. Farm type had no effect on numbers of cows feeding. There were more interactions between cows feeding at open feed-faces compared to head-bale barriers. At open feed-faces, there were more interactions on organic farms than non-organic. It is possible that organic cows were hungrier than non-organic cows after the arrival of new feed
Mesoscopic pinning forces in neutron star crusts
The crust of a neutron star is thought to be comprised of a lattice of nuclei
immersed in a sea of free electrons and neutrons. As the neutrons are
superfluid their angular momentum is carried by an array of quantized vortices.
These vortices can pin to the nuclear lattice and prevent the neutron
superfluid from spinning down, allowing it to store angular momentum which can
then be released catastrophically, giving rise to a pulsar glitch. A crucial
ingredient for this model is the maximum pinning force that the lattice can
exert on the vortices, as this allows us to estimate the angular momentum that
can be exchanged during a glitch. In this paper we perform, for the first time,
a detailed and quantitative calculation of the pinning force \emph{per unit
length} acting on a vortex immersed in the crust and resulting from the
mesoscopic vortex-lattice interaction. We consider realistic vortex tensions,
allow for displacement of the nuclei and average over all possible orientation
of the crystal with respect to the vortex. We find that, as expected, the
mesoscopic pinning force becomes weaker for longer vortices and is generally
much smaller than previous estimates, based on vortices aligned with the
crystal. Nevertheless the forces we obtain still have maximum values of order
dyn/cm, which would still allow for enough
angular momentum to be stored in the crust to explain large Vela glitches, if
part of the star is decoupled during the event.Comment: 17 pages, 16 figures, 5 table
Oscillatory phase transition and pulse propagation in noisy integrate-and-fire neurons
We study non-locally coupled noisy integrate-and-fire neurons with the
Fokker-Planck equation. A propagating pulse state and a wavy state appear as a
phase transition from an asynchronous state. We also find a solution in which
traveling pulses are emitted periodically from a pacemaker region.Comment: 9 pages, 4 figure
Gravitational waves from rapidly rotating neutron stars
Rapidly rotating neutron stars in Low Mass X-ray Binaries have been proposed
as an interesting source of gravitational waves. In this chapter we present
estimates of the gravitational wave emission for various scenarios, given the
(electromagnetically) observed characteristics of these systems. First of all
we focus on the r-mode instability and show that a 'minimal' neutron star model
(which does not incorporate exotica in the core, dynamically important magnetic
fields or superfluid degrees of freedom), is not consistent with observations.
We then present estimates of both thermally induced and magnetically sustained
mountains in the crust. In general magnetic mountains are likely to be
detectable only if the buried magnetic field of the star is of the order of
G. In the thermal mountain case we find that gravitational
wave emission from persistent systems may be detected by ground based
interferometers. Finally we re-asses the idea that gravitational wave emission
may be balancing the accretion torque in these systems, and show that in most
cases the disc/magnetosphere interaction can account for the observed spin
periods.Comment: To appear in 'Gravitational Waves Astrophysics: 3rd Session of the
Sant Cugat Forum on Astrophysics, 2014', Editor: Carlos F. Sopuert
Dynamical mean-filed approximation to small-world networks of spiking neurons: From local to global, and/or from regular to random couplings
By extending a dynamical mean-field approximation (DMA) previously proposed
by the author [H. Hasegawa, Phys. Rev. E {\bf 67}, 41903 (2003)], we have
developed a semianalytical theory which takes into account a wide range of
couplings in a small-world network. Our network consists of noisy -unit
FitzHugh-Nagumo (FN) neurons with couplings whose average coordination number
may change from local () to global couplings () and/or
whose concentration of random couplings is allowed to vary from regular
() to completely random (p=1). We have taken into account three kinds of
spatial correlations: the on-site correlation, the correlation for a coupled
pair and that for a pair without direct couplings. The original -dimensional {\it stochastic} differential equations are transformed to
13-dimensional {\it deterministic} differential equations expressed in terms of
means, variances and covariances of state variables. The synchronization ratio
and the firing-time precision for an applied single spike have been discussed
as functions of and . Our calculations have shown that with increasing
, the synchronization is {\it worse} because of increased heterogeneous
couplings, although the average network distance becomes shorter. Results
calculated by out theory are in good agreement with those by direct
simulations.Comment: 19 pages, 2 figures: accepted in Phys. Rev. E with minor change
Nuclear Equation of State from Observations of Short Gamma-Ray Burst Remnants
The favoured progenitor model for short -ray bursts (SGRBs) is the
merger of two neutron stars that triggers an explosion with a burst of
collimated -rays. Following the initial prompt emission, some SGRBs
exhibit a plateau phase in their -ray light curves that indicates additional
energy injection from a central engine, believed to be a rapidly rotating,
highly magnetised neutron star. The collapse of this `protomagnetar' to a black
hole is likely to be responsible for a steep decay in -ray flux observed at
the end of the plateau. In this letter, we show that these observations can be
used to effectively constrain the equation of state of dense matter. In
particular, we show that the known distribution of masses in binary neutron
star systems, together with fits to the -ray light curves, provide
constraints that exclude the softest and stiffest plausible equations of state.
We further illustrate how a future gravitational wave observation with Advanced
LIGO/Virgo can place tight constraints on the equation of state, by adding into
the picture a measurement of the chirp mass of the SGRB progenitor.Comment: accepted for publication in Phys. Rev.
The enigmatic spin evolution of PSR J0537-6910: r-modes, gravitational waves and the case for continued timing
We discuss the unique spin evolution of the young X-ray pulsar PSR
J0537-6910, a system in which the regular spin down is interrupted by glitches
every few months. Drawing on the complete timing data from the Rossi X-ray
Timing Explorer (RXTE, from 1999-2011), we argue that a trend in the
inter-glitch behaviour points to an effective braking index close to ,
much larger than expected. This value is interesting because it would accord
with the neutron star spinning down due to gravitational waves from an unstable
r-mode. We discuss to what extent this, admittedly speculative, scenario may be
consistent and if the associated gravitational-wave signal would be within
reach of ground based detectors. Our estimates suggest that one may, indeed, be
able to use future observations to test the idea. Further precision timing
would help enhance the achievable sensitivity and we advocate a joint observing
campaign between the Neutron Star Interior Composition ExploreR (NICER) and the
LIGO-Virgo network.Comment: 10 pages, 4 figures, emulate ApJ forma
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