790 research outputs found
Limit Conditions in an Encounter of Theology with Neuroscience
Insofar as theology is responsible to its religious sources, it seeks to answer religious questions, such as, for Christians, \"What must I do to be saved?\" However, theology also involves asking whether such a question is the right one at all. This essay attempts an innovative approach to this question by investigating the intelligibility of \"the soul.\" Much recent neurobiology suggests that, even if a defensible notion of soul can be presented, it is unclear that it would allow meaningful talk about salvation
The Euclid-Mullin graph
We introduce the Euclid-Mullin graph, which encodes all instances of Euclid's
proof of the infinitude of primes. We investigate structural properties of the
graph both theoretically and numerically; in particular, we prove that it is
not a tree.Comment: 24 pages, 2 figures, to appear in Journal of Number Theor
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Plus/minus
textThe report details the development, pre-production, production, and post-production stages of Plus/Minus. Plus/Minus is a short, narrative film about about a young couple examining their relationship as they await the result of a pregnancy test.Radio-Television-Fil
A feasibility study towards ultra-thin PV solar cell devices by MOCDV based on a p-i-n structure incorporating pyrite
FeSx layers were deposited onto aluminosilicate glass substrates over a temperature range of 180°C to 500°C using a horizontal AP-MOCVD reactor. Fe(CO)5 was used as the Fe source in combination with t-Bu2S2 or t-BuSH as S precursor to control the rate of reaction and film stoichiometry. The Fe and S partial pressures were kept at 7.5 x 103 and 3.0 mbar, giving a gas phase S/Fe ratio of 400. Reactions followed a non-Arrhenius relationship at higher temperatures. XRD revealed mixed FeSx phases in the layers, which consisted mainly of FeS and Fe1-xS. Post growth annealing of the FeSx films using S powder in a static argon atmosphere and temperatures ranging from 250°C to 400°C was carried out using a 30 minute soak time. Characterisation by XRD confirmed a transitional phase change to FeS2 for the S anneal at 400°C. These films were highly absorbing in the visible region of the solar spectrum, which extended into the NIR. Devices with a p-i-n structure were produced using either a sulphurised or non-sulphurised FeSx i-layer, and compared to p-n devices without an i-layer. A non-sulphurised p-i-n device had the best I-V results, which was attributed to reduced lateral inhomogeneity across the device relative to the thinner p-n device structures. Devices with sulphurised FeSx i-layers performed least efficiently which is suspected to be due to a less defined FeSx/CdS junction caused by severe conditions during the S annealing process
Coulomb Oscillations of Indium-doped ZnO Nanowire Transistors in a Magnetic Field
We report on the observation of Coulomb oscillations from localized quantum
dots superimposed on the normal hopping current in ZnO nanowire transistors.
The Coulomb oscillations can be resolved up to 20 K. Positive anisotropic
magnetoresistance has been observed due to the Lorentz force on the carrier
motion. Magnetic field-induced tunneling barrier transparency results in an
increase of oscillation amplitude with increasing magnetic field. The energy
shift as a function of magnetic field indicates electron wavefunction
modification in the quantum dots.Comment: 16 pages, 6 figure
Magnonic Charge Pumping via Spin-Orbit Coupling
The interplay between spin, charge, and orbital degrees of freedom has led to
the development of spintronic devices like spin-torque oscillators, spin-logic
devices, and spin-transfer torque magnetic random-access memories. In this
development spin pumping, the process where pure spin-currents are generated
from magnetisation precession, has proved to be a powerful method for probing
spin physics and magnetisation dynamics. The effect originates from direct
conversion of low energy quantised spin-waves in the magnet, known as magnons,
into a flow of spins from the precessing magnet to adjacent normal metal leads.
The spin-pumping phenomenon represents a convenient way to electrically detect
magnetisation dynamics, however, precessing magnets have been limited so far to
pump pure spin currents, which require a secondary spin-charge conversion
element such as heavy metals with large spin Hall angle or multi-layer layouts
to be detectable. Here, we report the experimental observation of charge
pumping in which a precessing ferromagnet pumps a charge current, demonstrating
direct conversion of magnons into high-frequency currents via the relativistic
spin-orbit interaction. The generated electric current, differently from spin
currents generated by spin-pumping, can be directly detected without the need
of any additional spin to charge conversion mechanism and amplitude and phase
information about the relativistic current-driven magnetisation dynamics. The
charge-pumping phenomenon is generic and gives a deeper understanding of the
recently observed spin-orbit torques, of which it is the reciprocal effect and
which currently attract interest for their potential in manipulating magnetic
information. Furthermore, charge pumping provides a novel link between
magnetism and electricity and may find application in sourcing alternating
electric currents.Comment: 3 figure
Restrictive antibiotic stewardship associated with reduced hospital mortality in gram-negative infection
Introduction: Antimicrobial stewardship has an important role in the control of Clostridium difficile infection (CDI) and antibiotic resistance. An important component of UK stewardship interventions is the restriction of broad-spectrum beta-lactam antibiotics and promotion of agents associated with a lower risk of CDI such as gentamicin. Whilst the introduction of restrictive antibiotic guidance has been associated with improvements in CDI and antimicrobial resistance evidence of the effect on outcome following severe infection is lacking.
Methods: In 2008, Glasgow hospitals introduced a restrictive antibiotic guideline. A retrospective before/after study assessed outcome following gram-negative bacteraemia in the 2-year period around implementation.
Results: Introduction of restrictive antibiotic guidelines was associated with a reduction in utilisation of ceftriaxone and co-amoxiclav and an increase in amoxicillin and gentamicin. 1593 episodes of bacteraemia were included in the study. The mortality over 1 year following gram-negative bacteraemia was lower in the period following guideline implementation (RR 0.852, P = 0.045). There was no evidence of a difference in secondary outcomes including ITU admission, length of stay, readmission, recurrence of bacteraemia and need for renal replacement therapy. There was a fall in CDI (RR 0.571, P = 0.014) and a reduction in bacterial resistance to ceftriaxone and co-amoxiclav but no evidence of an increase in gentamicin resistance after guideline implementation.
Conclusion: Restrictive antibiotic guidelines were associated with a reduction in CDI and bacterial resistance but no evidence of adverse outcomes following gram-negative bacteraemia. There was a small reduction in one year mortality
Isolating Triggered Star Formation
Galaxy pairs provide a potentially powerful means of studying triggered star
formation from galaxy interactions. We use a large cosmological N-body
simulation coupled with a well-tested semi-analytic substructure model to
demonstrate that the majority of galaxies in close pairs reside within cluster
or group-size halos and therefore represent a biased population, poorly suited
for direct comparison to ``field'' galaxies. Thus, the frequent observation
that some types of galaxies in pairs have redder colors than ``field'' galaxies
is primarily a selection effect. We select galaxy pairs that are isolated in
their dark matter halos with respect to other massive subhalos (N=2 halos) and
a control sample of isolated galaxies (N=1 halos) for comparison. We then apply
these selection criteria to a volume-limited subset of the 2dF Galaxy Redshift
Survey with M_Bj <= -19 and obtain the first clean measure of the typical
fraction of galaxies affected by triggered star formation and the average
elevation in the star formation rate. We find that 24% (30.5%) of these L^\star
and sub-L^{\star} galaxies in isolated 50 (30) kpc/h pairs exhibit star
formation that is boosted by a factor of >~ 5 above their average past value,
while only 10% of isolated galaxies in the control sample show this level of
enhancement. Thus, 14% (20 %) of the galaxies in these close pairs show clear
triggered star formation. The isolation criteria we develop provide a means to
constrain star formation and feedback prescriptions in hydrodynamic simulations
and a very general method of understanding the importance of triggered star
formation in a cosmological context. (Abridged.)Comment: 12 pages, 10 figures, emulateapj format, accepted by Ap
Real-time compression of IEC 61869-9 sampled value data
Fast-acting, yet cost-effective, communications is critical for smarter grid monitoring, protection, and control. This paper demonstrates a new approach for the real-time compression of Sampled Value (SV) data based on the IEC 61869-9 recommendations. This approach applies simple compression rules, yet yields excellent compression performance---typically compressing data to less than half of the original size. This leads to a significant and beneficial reduction in encoding time (in the merging unit producing the SV data) and decoding time (at the end application), as well as the main benefit of reduced Ethernet transmission times resulting from the reduced frame size. As well as reducing the absolute bandwidth requirements in typical applications, this has system-wide benefits due to reducing Ethernet queuing delays and the consequent network jitter. The approach has been validated on a real-time platform to accurately measure all contributions to the end-to-end delay. This work will help enable low-latency and bandwidth-sensitive applications involving the SV protocol, such as phasor measurement units and wide-area protection
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