19,667 research outputs found
The Temperature Evolution of the Out-of-Plane Correlation Lengths of Charge-Stripe Ordered La(1.725)Sr(0.275)NiO(4)
The temperature dependence of the magnetic order of stripe-ordered
La(1.725)Sr(0.275)NiO(4) is investigated by neutron diffraction. Upon cooling,
the widths if the magnetic Bragg peaks are observed to broaden. The degree of
broadening is found to be very different for l = odd-integer and l =
even-integer magnetic peaks. We argue that the observed behaviour is a result
of competition between magnetic and charge order.Comment: 3 figure
MCMC Exploration of Supermassive Black Hole Binary Inspirals
The Laser Interferometer Space Antenna will be able to detect the inspiral
and merger of Super Massive Black Hole Binaries (SMBHBs) anywhere in the
Universe. Standard matched filtering techniques can be used to detect and
characterize these systems. Markov Chain Monte Carlo (MCMC) methods are ideally
suited to this and other LISA data analysis problems as they are able to
efficiently handle models with large dimensions. Here we compare the posterior
parameter distributions derived by an MCMC algorithm with the distributions
predicted by the Fisher information matrix. We find excellent agreement for the
extrinsic parameters, while the Fisher matrix slightly overestimates errors in
the intrinsic parameters.Comment: Submitted to CQG as a GWDAW-10 Conference Proceedings, 9 pages, 5
figures, Published Versio
Massive, Absorption-selected Galaxies at Intermediate Redshifts
The nature of absorption-selected galaxies and their connection to the
general galaxy population have been open issues for more than three decades,
with little information available on their gas properties. Here we show, using
detections of carbon monoxide (CO) emission with the Atacama Large
Millimeter/submillimeter Array (ALMA), that five of seven high-metallicity,
absorption-selected galaxies at intermediate redshifts, ,
have large molecular gas masses, and high molecular gas fractions (. Their modest star
formation rates (SFRs), yr, then
imply long gas depletion timescales, Gyr. The
high-metallicity absorption-selected galaxies at appear
distinct from populations of star-forming galaxies at both ,
during the peak of star formation activity in the Universe, and lower
redshifts, . Their relatively low SFRs, despite the large
molecular gas reservoirs, may indicate a transition in the nature of star
formation at intermediate redshifts, .Comment: 8 pages, 3 figures; accepted for publication in Astrophysical Journal
Letters. Minor changes to match the version in press in ApJ
Plasmon-Emitter Interactions at the Nanoscale
Plasmon-emitter interactions are of paramount importance in modern
nanoplasmonics and are generally maximal at short emitter-surface separations.
However, when the separation falls below 10-20 nm, the classical theory
progressively deteriorates due to its neglect of quantum mechanical effects
such as nonlocality, electronic spill-out, and Landau damping. Here, we show
how this neglect can be remedied by presenting a unified theoretical treatment
of mesoscopic electrodynamics grounded on the framework of Feibelman
-parameters. Crucially, our technique naturally incorporates nonclassical
resonance shifts and surface-enabled Landau damping - a nonlocal damping effect
- which have a dramatic impact on the amplitude and spectral distribution of
plasmon-emitter interactions. We consider a broad array of plasmon-emitter
interactions ranging from dipolar and multipolar spontaneous emission
enhancement, to plasmon-assisted energy transfer and enhancement of two-photon
transitions. The formalism presented here gives a complete account of both
plasmons and plasmon-emitter interactions at the nanoscale, constituting a
simple yet rigorous and general platform to incorporate nonclassical effects in
plasmon-empowered nanophotonic phenomena.Comment: 12 pages, 6 figure
Generalised Sandpile Dynamics on Artificial and Real-World Directed Networks
The main finding of this paper is a novel avalanche-size exponent Ï â 1.87 when the generalised sandpile dynamics evolves on the real-world Japanese inter-firm network. The topology of this network is non-layered and directed, displaying the typical bow tie structure found in real-world directed networks, with cycles and triangles. We show that one can move from a strictly layered regular lattice to a more fluid structure of the inter-firm network in a few simple steps. Relaxing the regular lattice structure by introducing an interlayer distribution for the interactions, forces the scaling exponent of the avalanche-size probability density function Ï out of the two-dimensional directed sandpile universality class Ï = 4/3, into the mean field universality class Ï = 3/2. Numerical investigation shows that these two classes are the only that exist on the directed sandpile, regardless of the underlying topology, as long as it is strictly layered. Randomly adding a small proportion of links connecting non adjacent layers in an otherwise layered network takes the system out of the mean field regime to produce non-trivial avalanche-size probability density function. Although these do not display proper scaling, they closely reproduce the behaviour observed on the Japanese inter-firm network
Using in situ technique to estimate nutrient availability of six barley varieties for ruminants
Non-Peer ReviewedBarley grains are as a main source of feed for ruminants in Canada. Although barley varieties have similar chemical composition, they exhibit different rumen degradation characteristics and nutrient availability. The objective of this study was to estimate nutrient availability of the six barley varieties using nylon bags incubated for 0, 2, 4, 8, 12, 24 and 48 h in the rumen of dairy cow and determine the rumen degradation parameters of DM, CP and starch according to the first order degradation kinetics equation. The results indicated that the barley varieties showed different degradation rate (Kd) of DM, CP and starch during incubation period. CDC Trey was the highest (P<0.05) in effective degradability of DM (498.04g/kg) while AC Metcalfe showed the highest (P<0.05) effective degradability of CP (63.06g/kg) and starch (344.82g/kg) compared with other barley varieties. CDC Helgason had the largest size of rumen undegradable fraction of DM (640.21g/kg), CP (83.85g/kg, NRC 2001 model) and starch (321.85g/kg). Feeds degradation features from this study involved nutrients utilization in ruminant digestive systems. Further study to investigate and compare the structural/chemical make-up characteristics between barley varieties may provide more information as to why barley varieties exhibit different biodegradation behaviors
Using synchrotron-based FTIR microspectroscopy (SFTIRM) to reveal the differences of endosperm structural and chemical make-up among six barley varieties
Non-Peer ReviewedBarley grains are widely used for malting and feeding purposes in Canada. Although barley varieties have similar chemical composition, they exhibit different rumen degradation characteristics and nutrient availability. The objectives of this study was to determine structural make-up features and identify the structural differences in chemical functional groups in endosperm tissue among the six barley varieties using ultra-spatially resolved synchrotron-based FTIR microspectroscopy (SFTIRM). The results indicated that the barley varieties showed significant differences in terms of peak area intensities and the peak ratios of the amide I (1650 cm-1) and amide II (1550 cm-1), cellulosic compounds (ca. 1240 cm-1), and non-structural carbohydrates (NSC, starch) peak (1025 cm-1). The synchrotron-based FTIR spectroscopic information associated with structural and chemical make-up characteristics of barley grains may provide more information as to why barley varieties exhibit different biodegradation behaviors
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