654 research outputs found
Local spatio-temporal encoding of raw perfusion MRI for the prediction of final lesion in stroke
We address the medical image analysis issue of predicting the final lesion in stroke from early perfusion magnetic resonance imaging. The classical processing approach for the dynamical perfusion images consists in a temporal deconvolution to improve the temporal signals associated with each voxel before performing prediction. We demonstrate here the value of exploiting directly the raw perfusion data by encoding the local environment of each voxel as a spatio-temporal texture, with an observation scale larger than the voxel. As a first illustration for this approach, the textures are characterized with local binary patterns and the classification is performed using a standard support vector machine (SVM). This simple machine learning classification scheme demonstrates results with 95% accuracy on average while working only raw perfusion data. We discuss the influence of the observation scale and evaluate the interest of using post-processed perfusion data with this approach
Modelling the influence of RKIP on the ERK signalling pathway using the stochastic process algebra PEPA
This paper examines the influence of the Raf Kinase Inhibitor Protein (RKIP) on the Extracellular signal Regulated Kinase (ERK) signalling pathway [5] through modelling in a Markovian process algebra, PEPA [11]. Two models of the system are presented, a reagent-centric view and a pathway-centric view. The models capture functionality at the level of subpathway, rather than at a molecular level. Each model affords a different perspective of the pathway and analysis. We demonstrate the two models to be formally equivalent using the timing-aware bisimulation defined over PEPA models and discuss the biological significance
Evaluation of fermented whole crop wheat and barley feeding on growth performance, nutrient digestibility, faecal volatile fatty acid emission, blood constituents, and faecal microbiota in growing pigs
This study was conducted to determine the effects of feeding diets with fermented whole crop wheat (FWW) and fermented whole crop barley (FWB) on growth performance, nutrient digestibility, blood constituents, faecal volatile fatty acid (VFA) emission and faecal microbiota in growing pigs. A total of 200 growing pigs were randomly allotted to five treatments with eight replicates per treatment and five pigs per replicate. Dietary treatments consisted of i) CON (basal diet), ii) 0.5% FWW (CON + 0.5% fermented whole crop wheat), iii) 1.0% FWW (CON + 1.0% fermented whole crop wheat), iv) 0.5% FWB (CON + 0.5% fermented whole crop barley), and v) 1.0% FWB (CON + 1.0% fermented whole crop barley). The digestibility of total dietary fibre was significantly higher in pigs fed FWW diets. The faecal emissions of VFA of pigs fed the fermented treatments was increased significantly compared with CON. Concentrations of cortisol and triglyceride in blood of pigs fed 1.0% FWW were significantly lower than pigs fed CON diets. The pigs fed 1.0% FWB diets had a significantly decreased level of total cholesterol in blood compared with CON. In conclusion, the current results indicated that diets supplemented with FWW and FWB could increase faecal VFA emission and reduce concentration of triglyceride and cortisol, while 0.5% and 1.0% FWW had no negative effects on growth performance, and could increase digestibility of dietary fibre in growing pigs.Keywords:Â Dietary fibre, faecal short-chain fatty acid emissions, fermented feed, serum parameter, swin
Vacuumless topological defects in Lyra geometry
Few years ago, Cho and Vilenkin have proposed that topological defects can
arise in symmetry breaking models without having degenerate vacua. These types
of defects are known as vacuumless defects. In the present work, the
gravitational field of a vacuumless global string and global monopole have been
investigated in the context of Lyra geometry. We find the metric of the
vacuumless global string and global monopole in the weak field approximations.
It has been shown that the vacuumless global string can have repulsive whereas
global monopole exerts attractive gravitational effects on a test particle. It
is dissimilar to the case studied in general relativity.Comment: 14 pages, 9 figures. To appear in Astrophys.Space.Sc
Certain subclasses of multivalent functions defined by new multiplier transformations
In the present paper the new multiplier transformations
\mathrm{{\mathcal{J}% }}_{p}^{\delta }(\lambda ,\mu ,l) (\delta ,l\geq
0,\;\lambda \geq \mu \geq 0;\;p\in \mathrm{% }%\mathbb{N} )} of multivalent
functions is defined. Making use of the operator two new subclasses and \textbf{\ }of multivalent analytic
functions are introduced and investigated in the open unit disk. Some
interesting relations and characteristics such as inclusion relationships,
neighborhoods, partial sums, some applications of fractional calculus and
quasi-convolution properties of functions belonging to each of these subclasses
and
are
investigated. Relevant connections of the definitions and results presented in
this paper with those obtained in several earlier works on the subject are also
pointed out
Detection of Quantitative Trait Loci Affecting Fat Deposition Traits in Pigs
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License http://creativecommons.org/licenses/by-nc/3.0/ which permits unrestricted noncommercial use, distribution, and reproduction in any medium, provided the original work is properly cited.Quantitative trait loci (QTL) associated with fat deposition traits in pigs are important gene positions in a chromosome that influence meat quality of pork. For QTL study, a three generation resource population was constructed from a cross between Korean native boars and Landrace sows. A total of 240 F2 animals from intercross of F1 were produced. 80 microsatellite markers covering chromosomes 1 to 10 were selected to genotype the resource population. Intervals between adjacent markers were approximately 19 cM. Linkage analysis was performed using CRIMAP software version 2.4 with a FIXED option to obtain the map distances. For QTL analysis, the public web-based software, QTL express (http://www.qtl.cap.ed.ac.uk) was used. Two significant and two suggestive QTL were identified on SSC 6, 7, and 8 as affecting body fat and IMF traits. For QTL affecting IMF, the most significant association was detected between marker sw71 and sw1881 on SSC 6, and a suggestive QTL was identified between sw268 and sw205 on SSC8. These QTL accounted for 26.58% and 12.31% of the phenotypic variance, respectively. A significant QTL affecting IMF was detected at position 105 cM between markers sw71 and sw1881 on SSC 6
Kinetic Turbulence
The weak collisionality typical of turbulence in many diffuse astrophysical
plasmas invalidates an MHD description of the turbulent dynamics, motivating
the development of a more comprehensive theory of kinetic turbulence. In
particular, a kinetic approach is essential for the investigation of the
physical mechanisms responsible for the dissipation of astrophysical turbulence
and the resulting heating of the plasma. This chapter reviews the limitations
of MHD turbulence theory and explains how kinetic considerations may be
incorporated to obtain a kinetic theory for astrophysical plasma turbulence.
Key questions about the nature of kinetic turbulence that drive current
research efforts are identified. A comprehensive model of the kinetic turbulent
cascade is presented, with a detailed discussion of each component of the model
and a review of supporting and conflicting theoretical, numerical, and
observational evidence.Comment: 31 pages, 3 figures, 99 references, Chapter 6 in A. Lazarian et al.
(eds.), Magnetic Fields in Diffuse Media, Astrophysics and Space Science
Library 407, Springer-Verlag Berlin Heidelberg (2015
A Study of Cosmic Ray Secondaries Induced by the Mir Space Station Using AMS-01
The Alpha Magnetic Spectrometer (AMS-02) is a high energy particle physics
experiment that will study cosmic rays in the to range and will be installed on the International Space Station
(ISS) for at least 3 years. A first version of AMS-02, AMS-01, flew aboard the
space shuttle \emph{Discovery} from June 2 to June 12, 1998, and collected
cosmic ray triggers. Part of the \emph{Mir} space station was within the
AMS-01 field of view during the four day \emph{Mir} docking phase of this
flight. We have reconstructed an image of this part of the \emph{Mir} space
station using secondary and emissions from primary cosmic rays
interacting with \emph{Mir}. This is the first time this reconstruction was
performed in AMS-01, and it is important for understanding potential
backgrounds during the 3 year AMS-02 mission.Comment: To be submitted to NIM B Added material requested by referee. Minor
stylistic and grammer change
Probing exotic phenomena at the interface of nuclear and particle physics with the electric dipole moments of diamagnetic atoms: A unique window to hadronic and semi-leptonic CP violation
The current status of electric dipole moments of diamagnetic atoms which
involves the synergy between atomic experiments and three different theoretical
areas -- particle, nuclear and atomic is reviewed. Various models of particle
physics that predict CP violation, which is necessary for the existence of such
electric dipole moments, are presented. These include the standard model of
particle physics and various extensions of it. Effective hadron level combined
charge conjugation (C) and parity (P) symmetry violating interactions are
derived taking into consideration different ways in which a nucleon interacts
with other nucleons as well as with electrons. Nuclear structure calculations
of the CP-odd nuclear Schiff moment are discussed using the shell model and
other theoretical approaches. Results of the calculations of atomic electric
dipole moments due to the interaction of the nuclear Schiff moment with the
electrons and the P and time-reversal (T) symmetry violating
tensor-pseudotensor electron-nucleus are elucidated using different
relativistic many-body theories. The principles of the measurement of the
electric dipole moments of diamagnetic atoms are outlined. Upper limits for the
nuclear Schiff moment and tensor-pseudotensor coupling constant are obtained
combining the results of atomic experiments and relativistic many-body
theories. The coefficients for the different sources of CP violation have been
estimated at the elementary particle level for all the diamagnetic atoms of
current experimental interest and their implications for physics beyond the
standard model is discussed. Possible improvements of the current results of
the measurements as well as quantum chromodynamics, nuclear and atomic
calculations are suggested.Comment: 46 pages, 19 tables and 16 figures. A review article accepted for
EPJ
Search for Higgs bosons decaying to tautau pairs in ppbar collisions at sqrt(s) = 1.96 TeV
We present a search for the production of neutral Higgs bosons decaying into
tautau pairs in ppbar collisions at a center-of-mass energy of 1.96 TeV. The
data, corresponding to an integrated luminosity of 5.4 fb-1, were collected by
the D0 experiment at the Fermilab Tevatron Collider. We set upper limits at the
95% C.L. on the product of production cross section and branching ratio for a
scalar resonance decaying into tautau pairs, and we then interpret these limits
as limits on the production of Higgs bosons in the minimal supersymmetric
standard model (MSSM) and as constraints in the MSSM parameter space.Comment: 7 pages, 5 figures, submitted to PL
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