1,348 research outputs found
Large Hadroproduction of as a Probe of Gluon Distribution inside Proton
The transverse momentum distribution of single vector boson production at
hadron colliders provides useful ways of testing the Standard Model and
searching new physics beyond the Standard Model. We study large
hadroproduction of -boson as a probe of gluon distributions inside proton.
We investigate how to get initial gluon-involving contributions, or how to
subtract quark-quark (or -antiquark) contributions from total cross section. We
also investigated the simultaneous measurement of the rapidity and the
transverse momentum of the produced boson, to obtain momentum fractions of
initial partons. And we extracted relevant uncertainties involving in
experimental and theoretical analyses. This large hadroproduction of
can be used as constraints on analyses of global parton (gluon and quarks)
distribution functions inside proton.Comment: (a) 13 pages(LaTeX) + 1 figure ps file(3 pages):compressed, uuencoded
(b) accepted by Phys.Lett.B. (c) some figures are combined and one is
omitted. (d) conclusion part is included into abstrac
Search for New Physics in the Semileptonic D_{l4} Decays, D->K \pi l \nu
New physics effects through the direct CP violation and the decay rate change
are investigated in the semileptonic decays, , by including a scalar-exchange interaction with a complex coupling. In
the decay process, we included various excited states as intermediate states
decaying to the final hadrons, , and found that among the intermediate
states only the lowest state () is dominant and the other higher excited
states are negligible, contrary to the decays. We also obtained
constraints on the new complex coupling within the multi-Higgs doublet model
and the scalar leptoquark models.Comment: LaTeX, 16 pages, including 3 figure
Primary Sequence and Developmental Expression Pattern of mRNAs and Protein for an α1Subunit of the Sodium Pump Cloned from the Neural Plate ofXenopus laevis
AbstractExpression of a catalytic α subunit of the sodium pump was followed in earlyXenopusembryos for correlation with physiological experiments showing that the sodium pump controls cavity expansion and the differentiation of neurones from the neural plate. Two cDNAs (one full length, one partial) for α1subunit isoforms were cloned from a neural plate stageXenopuslibrary and sequenced. Other isoforms were not detected. Temporal and spatial expression patterns for α1subunit transcripts and protein revealed extensive developmental regulation. At all stages, cells involved in cavity generation (outer ectoderm and cells lining the archenteron) expressed α1transcripts with protein confined to the lateral and basal membranes. Before gastrulation, transcript levels were low and predominantly in animal cells. During gastrulation, α1mRNAs rose significantly. Transcripts and protein were down-regulated in future outer neural plate cells as the mesoderm invaginated. Protein appeared at the blastopore on apical surfaces of lip cells and apposing surfaces of invaginating cells, suggesting that the Na pump opposes entry of fluid. In early neurulae, α1mRNAs rose sharply. Transcript expression remained low in outer neural plate cells and increased in the endoderm, and protein appeared in the notochord. In midneurulae, transcripts returned in outer neural plate cells. Protein expression appeared on basal surfaces of deep neural plate cells and the floor plate, matching physiological observations. After neural tube closure, transcripts were detected in all dorsal structures. Protein was retained in the notochord and floor plate, was eliminated from the outer layer of the neural tube, and appeared on ependymal cells. The results are discussed in relation to previous physiological observations
Graded-index magnonics
The wave solutions of the Landau–Lifshitz equation (spin waves) are characterized by some of the most
complex and peculiar dispersion relations among all waves. For example, the spin-wave (“magnonic”) dispersion
can range from the parabolic law (typical for a quantum-mechanical electron) at short wavelengths to the
nonanalytical linear type (typical for light and acoustic phonons) at long wavelengths. Moreover, the longwavelength
magnonic dispersion has a gap and is inherently anisotropic, being naturally negative for a range of
relative orientations between the effective field and the spin-wave wave vector. Nonuniformities in the effective
field and magnetization configurations enable the guiding and steering of spin waves in a deliberate manner and
therefore represent landscapes of graded refractive index (graded magnonic index). By analogy to the fields of
graded-index photonics and transformation optics, the studies of spin waves in graded magnonic landscapes can
be united under the umbrella of the graded-index magnonics theme and are reviewed here with focus on the challenges
and opportunities ahead of this exciting research direction
Turing machines can be efficiently simulated by the General Purpose Analog Computer
The Church-Turing thesis states that any sufficiently powerful computational
model which captures the notion of algorithm is computationally equivalent to
the Turing machine. This equivalence usually holds both at a computability
level and at a computational complexity level modulo polynomial reductions.
However, the situation is less clear in what concerns models of computation
using real numbers, and no analog of the Church-Turing thesis exists for this
case. Recently it was shown that some models of computation with real numbers
were equivalent from a computability perspective. In particular it was shown
that Shannon's General Purpose Analog Computer (GPAC) is equivalent to
Computable Analysis. However, little is known about what happens at a
computational complexity level. In this paper we shed some light on the
connections between this two models, from a computational complexity level, by
showing that, modulo polynomial reductions, computations of Turing machines can
be simulated by GPACs, without the need of using more (space) resources than
those used in the original Turing computation, as long as we are talking about
bounded computations. In other words, computations done by the GPAC are as
space-efficient as computations done in the context of Computable Analysis
Granular discharge and clogging for tilted hoppers
We measure the flux of spherical glass beads through a hole as a systematic
function of both tilt angle and hole diameter, for two different size beads.
The discharge increases with hole diameter in accord with the Beverloo relation
for both horizontal and vertical holes, but in the latter case with a larger
small-hole cutoff. For large holes the flux decreases linearly in cosine of the
tilt angle, vanishing smoothly somewhat below the angle of repose. For small
holes it vanishes abruptly at a smaller angle. The conditions for zero flux are
discussed in the context of a {\it clogging phase diagram} of flow state vs
tilt angle and ratio of hole to grain size
Infrared exponents and the strong-coupling limit in lattice Landau gauge
We study the gluon and ghost propagators of lattice Landau gauge in the
strong-coupling limit beta=0 in pure SU(2) lattice gauge theory to find
evidence of the conformal infrared behavior of these propagators as predicted
by a variety of functional continuum methods for asymptotically small momenta
. In the strong-coupling limit, this same
behavior is obtained for the larger values of a^2q^2 (in units of the lattice
spacing a), where it is otherwise swamped by the gauge field dynamics.
Deviations for a^2q^2 < 1 are well parameterized by a transverse gluon mass
. Perhaps unexpectedly, these deviations are thus no finite-volume
effect but persist in the infinite-volume limit. They furthermore depend on the
definition of gauge fields on the lattice, while the asymptotic conformal
behavior does not. We also comment on a misinterpretation of our results by
Cucchieri and Mendes in Phys. Rev. D81 (2010) 016005.Comment: 17 pages, 12 figures. Revised version (mainly sections I and II);
references and comments on subsequent work on the subject added
A global map to aid the identification and screening of critical habitat for marine industries
Marine industries face a number of risks that necessitate careful analysis prior to making decisions on the siting of operations and facilities. An important emerging regulatory framework on environmental sustainability for business operations is the International Finance Corporation’s Performance Standard 6 (IFC PS6). Within PS6, identification of biodiversity significance is articulated through the concept of “Critical Habitat”, a definition developed by the IFC and detailed through criteria aligned with those that support internationally accepted biodiversity designations. No publicly available tools have been developed in either the marine or terrestrial realm to assess the likelihood of sites or operations being located within PS6-defined Critical Habitat. This paper presents a starting point towards filling this gap in the form of a preliminary global map that classifies more than 13 million km2 of marine and coastal areas of importance for biodiversity (protected areas, Key Biodiversity Areas [KBA], sea turtle nesting sites, cold- and warm-water corals, seamounts, seagrass beds, mangroves, saltmarshes, hydrothermal vents and cold seeps) based on their overlap with Critical Habitat criteria, as defined by IFC. In total, 5798×103 km2 (1.6%) of the analysis area (global ocean plus coastal land strip) were classed as Likely Critical Habitat, and 7526×103 km2 (2.1%) as Potential Critical Habitat; the remainder (96.3%) were Unclassified. The latter was primarily due to the paucity of biodiversity data in marine areas beyond national jurisdiction and/or in deep waters, and the comparatively fewer protected areas and KBAs in these regions. Globally, protected areas constituted 65.9% of the combined Likely and Potential Critical Habitat extent, and KBAs 29.3%, not accounting for the overlap between these two features. Relative Critical Habitat extent in Exclusive Economic Zones varied dramatically between countries. This work is likely to be of particular use for industries operating in the marine and coastal realms as an early screening aid prior to in situ Critical Habitat assessment; to financial institutions making investment decisions; and to those wishing to implement good practice policies relevant to biodiversity management. Supplementary material (available online) includes other global datasets considered, documentation and justification of biodiversity feature classification, detail of IFC PS6 criteria/scenarios, and coverage calculations
Surface and capillary transitions in an associating binary mixture model
We investigate the phase diagram of a two-component associating fluid mixture
in the presence of selectively adsorbing substrates. The mixture is
characterized by a bulk phase diagram which displays peculiar features such as
closed loops of immiscibility. The presence of the substrates may interfere the
physical mechanism involved in the appearance of these phase diagrams, leading
to an enhanced tendency to phase separate below the lower critical solution
point. Three different cases are considered: a planar solid surface in contact
with a bulk fluid, while the other two represent two models of porous systems,
namely a slit and an array on infinitely long parallel cylinders. We confirm
that surface transitions, as well as capillary transitions for a large
area/volume ratio, are stabilized in the one-phase region. Applicability of our
results to experiments reported in the literature is discussed.Comment: 12 two-column pages, 12 figures, accepted for publication in Physical
Review E; corrected versio
A retrospective multi‐center study of treatment, outcome, and prognostic factors in 34 dogs with disseminated aspergillosis in Australia
Background
Disseminated aspergillosis (DA) in dogs has a guarded prognosis and there is a lack of a gold standard treatment protocol.
Objective
To retrospectively assess survival times and factors influencing survival times.
Animals
Dogs diagnosed with DA from January 2007 to June 2017.
Methods
Disseminated aspergillosis case data were retrieved from 13 Australian veterinary referral centers, with a diagnosis confirmed with culture or PCR. Factors influencing survival time after diagnosis were quantified using a Cox proportional hazards regression model.
Results
Thirty-four dogs met the study inclusion criteria. Twenty-two dogs were treated with antifungal treatment and 12 dogs received no antifungal treatment. Accounting for censoring of dogs that were either still alive on the date of data collection or were loss to follow-up, dogs treated with itraconazole alone (n = 8) had a median survival time (MST) of 63 (95% CI: 20−272) days compared to 830 (95% CI: 267-1259) days for the n = 14 dogs that received multimodal antifungal therapy
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