1,493 research outputs found
Tissue Specificity and Dynamics of Sex-Biased Gene Expression in a Common Frog Population with Differentiated, Yet Homomorphic, Sex Chromosomes.
Sex-biased genes are central to the study of sexual selection, sexual antagonism, and sex chromosome evolution. We describe a comprehensive de novo assembled transcriptome in the common frog <i>Rana temporaria</i> based on five developmental stages and three adult tissues from both sexes, obtained from a population with karyotypically homomorphic but genetically differentiated sex chromosomes. This allows the study of sex-biased gene expression throughout development, and its effect on the rate of gene evolution while accounting for pleiotropic expression, which is known to negatively correlate with the evolutionary rate. Overall, sex-biased genes had little overlap among developmental stages and adult tissues. Late developmental stages and gonad tissues had the highest numbers of stage- or tissue-specific genes. We find that pleiotropic gene expression is a better predictor than sex bias for the evolutionary rate of genes, though it often interacts with sex bias. Although genetically differentiated, the sex chromosomes were not enriched in sex-biased genes, possibly due to a very recent arrest of XY recombination. These results extend our understanding of the developmental dynamics, tissue specificity, and genomic localization of sex-biased genes
Azimuthal asymmetries in lepton-pair production at a fixed-target experiment using the LHC beams (AFTER)
A multi-purpose fixed-target experiment using the proton and lead-ion beams
of the LHC was recently proposed by Brodsky, Fleuret, Hadjidakis and Lansberg,
and here we concentrate our study on some issues related to the spin physics
part of this project (referred to as AFTER). We study the nucleon spin
structure through and processes with a fixed-target experiment using
the LHC proton beams, for the kinematical region with 7 TeV proton beams at the
energy in center-of-mass frame of two nucleons GeV. We calculate
and estimate the azimuthal asymmetries of unpolarized and
dilepton production processes in the Drell--Yan continuum region and at the
-pole. We also calculate the , and
azimuthal asymmetries of and dilepton production
processes with the target proton and deuteron longitudinally or transversally
polarized in the Drell--Yan continuum region and around resonances region.
We conclude that it is feasible to measure these azimuthal asymmetries,
consequently the three-dimensional or transverse momentum dependent parton
distribution functions (3dPDFs or TMDs), at this new AFTER facility.Comment: 15 pages, 40 figures. Version accepted for publication in EPJ
Left-right asymmetry for pion and kaon production in the semi-inclusive deep inelastic scattering process
We analyze the left-right asymmetry in the semi-inclusive deep inelastic
scattering (SIDIS) process without introducing any weighting functions. With
the current theoretical understanding, we find that the Sivers effect plays a
key role in our analysis. We use the latest parametrization of the Sivers and
fragmentation functions to reanalyze the production process and find
that the results are sensitive to the parametrization. We also extend our
calculation on the production, which can help us know more about the
Sivers distribution of the sea quarks and the unfavored fragmentation
processes. HERMES kinematics with a proton target, COMPASS kinematics with a
proton, deuteron, and neutron target (the information on the neutron target can
be effectively extracted from the He target), and JLab kinematics (both 6
GeV and 12 GeV) with a proton and neutron target are considered in our paper.Comment: 7 latex pages, 11 figures, final version for publication, with
references update
Best-Effort Patching for Multicast True VoD Service
A multicast Video-on-Demand (VoD) system allows clients to share a server stream by batching their requests, and hence, improves channel utilization. However, it is very difficult to equip such a VoD system with full support for interactive VCR functions which are important to a growing number of Internet applications. In order to eliminate service (admission) latency, patching was proposed to enable an existing multicast session to dynamically add new clients, and requests can be served without delay if patching channels are available. A true VoD (TVoD) service should support not only zero-delay client admission but also continuous VCR-like interactivity. However, the conventional patching is only suitable for admission control. We propose a new patching scheme, called Best-Effort Patching (BEP), that offers a TVoD service in terms of both request admission and VCR interactivity. Moreover, by using a novel dynamic merging algorithm, BEP significantly improves the efficiency of TVoD interactivity, especially for popular videos. We also model and evaluate the efficiency of the dynamic merging algorithm. It is shown that BEP outperforms the conventional TVoD interaction protocols.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47328/1/11042_2005_Article_6851.pd
Pairing symmetry and long range pair potential in a weak coupling theory of superconductivity
We study the superconducting phase with two component order parameter
scenario, such as, , where . We show, that in absence of orthorhombocity, the usual
does not mix with usual symmetry gap in an anisotropic band
structure. But the symmetry does mix with the usual d-wave for . The d-wave symmetry with higher harmonics present in it also mixes with
higher order extended wave symmetry. The required pair potential to obtain
higher anisotropic and extended s-wave symmetries, is derived by
considering longer ranged two-body attractive potential in the spirit of tight
binding lattice. We demonstrate that the dominant pairing symmetry changes
drastically from to like as the attractive pair potential is obtained
from longer ranged interaction. More specifically, a typical length scale of
interaction , which could be even/odd multiples of lattice spacing leads
to predominant wave symmetry. The role of long range interaction on
pairing symmetry has further been emphasized by studying the typical interplay
in the temperature dependencies of these higher order and wave pairing
symmetries.Comment: Revtex 8 pages, 7 figures embeded in the text, To appear in PR
The Use of the Cancellation Technique to Quantify the Hermann Grid Illusion
When observers view a grid of mid-gray lines superimposed on a black background, they report seeing illusory dark gray smudges at the grid intersections, an effect known as the Hermann grid illusion. The strength of the illusion is often measured using the cancellation technique: A white disk is placed over one of these intersections and the luminance of the disk is reduced until the disk disappears. Its luminance at this point, i.e., the disk's detection threshold, is taken to be a measure of the strength of the illusion. Our experiments showed that some distortions of the Hermann grid, which were sufficient to completely disrupt the illusion, did not reduce the disk's detection threshold. This showed that the cancellation technique is not a valid method for measuring the strength of the Hermann grid illusion. Those studies that attempted to use this technique inadvertently studied a different effect known as the blanking phenomenon. We conclude by presenting an explanation for the latter effect
Known Unknowns: Novelty Detection in Condition Monitoring
Abstract. In time-series analysis it is often assumed that observed data can be modelled as being derived from a number of regimes of dynamics, as e.g. in a Switching Kalman Filter (SKF) [8, 2]. However, it may not be possible to model all of the regimes, and in this case it can be useful to represent explicitly a ‘novel ’ regime. We apply this idea to the Factorial Switching Kalman Filter (FSKF) by introducing an extra factor (the ‘Xfactor’) to account for the unmodelled variation. We apply our method to physiological monitoring data from premature infants receiving intensive care, and demonstrate that the model is effective in detecting abnormal sequences of observations that are not modelled by the known regimes.
Sudden switch of generalized Lieb-Robinson velocity in a transverse field Ising spin chain
The Lieb-Robinson theorem states that the speed at which the correlations
between two distant nodes in a spin network can be built through local
interactions has an upper bound, which is called the Lieb-Robinson velocity.
Our central aim is to demonstrate how to observe the Lieb-Robinson velocity in
an Ising spin chain with a strong transverse field. We adopt and compare four
correlation measures for characterizing different types of correlations, which
include correlation function, mutual information, quantum discord, and
entanglement of formation. We prove that one of correlation functions shows a
special behavior depending on the parity of the spin number. All the
information-theoretical correlation measures demonstrate the existence of the
Lieb-Robinson velocity. In particular, we find that there is a sudden switch of
the Lieb-Robinson speed with the increasing of the number of spin
Simulating soil nitrogen fate in irrigated crop production with mature applications
Dairy manure is commonly applied to irrigated agricultural crops in the Magic Valley Region of southern Idaho, which has reported to impact the quality of surface and ground water. In this study, we used the Root Zone Water Quality Model (RZWQM2) to provide information about the long-term implications of manure applications. RZWQM2 was first calibrated and validated using 4 years of data from a long-term study with annual and biennial manure application rates of 18 Mg ha-1, 36 Mg ha-1, and 52 Mg ha-1, along with a control and conventional fertilizer treatment for crop yield, soil water and soil N. The 4-yr crop rotation was spring wheat (2013), potato (2014), spring barley (2015), and sugar beets (2016). RZWQM2 simulated soil water content, crop yield, total soil nitrogen, and soil nitrogen mineralization effectively as PBIAS and RRMSE for soil water content and crop yields were within the acceptable range (± 25% for PBIAS and <1.0 for RRMSE). Nitrate in the soil profile was overestimated, however in the acceptable range for the validation treatments. The calibrated model was then run for 16 years by repeating the management practices of the 4-year scenarios (4 crop rotations) for all treatments and 24 years for the 52 T Annual treatment (6 crop rotations). The 16-year simulation results showed that nitrogen seepage from annual manure treatments (for example, 18 T Annual vs 18 T Biennial) was 2.0 to 2.3 times higher than the nitrogen seepage from the biennial manure treatments. Increasing manure applications from 18 T Annual to 52 T Annual increased N seepage an average of 3.2 times for the 16-year rotation. Nitrogen seepage increased dramatically in rotations 3 and 4 compared to rotations 1 and 2 in the sixteen-year simulation. The 24-year simulation results showed after manure had been applied annually for 16 years and then applications terminated, the amount of N seepage returned initial levels in 8 years. In conclusion, to maintain clean ground water, manure applications would be best applied biennially and high applications should be discouraged
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