2,704 research outputs found
Elliptic flow of thermal photons at midrapidity in Au+Au collisions at GeV
The elliptic flow of thermal photons at midrapidity in Au+Au
collisions at GeV is predicted, based on three-dimensional
ideal hydrodynamics. Because of the interplay between the asymmetry and the
strength of the transverse flow, the thermal photon reaches a maximum
at \pt \sim 2GeV/ and the \pt-integrated reaches a maximum at
about 50% centrality. The \pt-integrated is very sensitive to the
lower limit of the integral but not sensitive to the upper limit due to the
rapid decrease in the spectrum of the transverse momentum.Comment: 4 pages, 2 figures - To appear in the conference proceedings for
Quark Matter 2009, March 30 - April 4, Knoxville, Tennesse
Elliptic flow of thermal photons in Au+Au collisions at GeV
The transverse momentum (pt) dependence, the centrality dependence and the
rapidity dependence of the elliptic flow of thermal photons in Au+Au collisions
at GeV are predicted, based on a three-dimensional ideal
hydrodynamic description of the hot and dense matter. The elliptic flow
parameter , i.e. the second Fourier coefficient of azimuthal
distribution, of thermal photons, first increases with \pt and then decreases
for \pt> 2 GeV/, due to the weak transverse flow at the early stage. The
\pt-integrated first increases with centrality, reaches a maximum at
about 50% centrality, and decreases. The rapidity dependence of the elliptic
flow of direct photons (mainly thermal photons) is very sensitive to
the initial energy density distribution along longitudinal direction, which
provides a useful tool to extract the realistic initial condition from
measurements.Comment: 6 pages, 6 figure
Adiabatic light propagation in nonlinear waveguide couplers with longitudinally varying detunings via resonance-locked inverse engineering
We investigate the adiabatic evolution of light in nonlinear waveguide
couplers via resonance-locked inverse engineering based on stimulated Raman
adiabatic passage (STIRAP). The longitudinal varying detunings of the
propagation coefficients are designed to eliminate dynamically the nonlinear
effect, which induce the non-adiabatic oscillations. We show that different
light evolutions such as complete light transfer, light split and light return
can be realized adiabatically with appropriate choices of the detunings even in
the nonlinear regime. The features open new opportunities for the realization
of all-optical nonlinear devices with high fidelity in integrated optics.Comment: 8 pages,6 figure
Rice Hypersensitive Induced Reaction Protein 1 (OsHIR1) associates with plasma membrane and triggers hypersensitive cell death
<p>Abstract</p> <p>Background</p> <p>In plants, HIR (Hypersensitive Induced Reaction) proteins, members of the PID (Proliferation, Ion and Death) superfamily, have been shown to play a part in the development of spontaneous hypersensitive response lesions in leaves, in reaction to pathogen attacks. The levels of HIR proteins were shown to correlate with localized host cell deaths and defense responses in maize and barley. However, not much was known about the HIR proteins in rice. Since rice is an important cereal crop consumed by more than 50% of the populations in Asia and Africa, it is crucial to understand the mechanisms of disease responses in this plant. We previously identified the rice HIR1 (OsHIR1) as an interacting partner of the OsLRR1 (rice Leucine-Rich Repeat protein 1). Here we show that OsHIR1 triggers hypersensitive cell death and its localization to the plasma membrane is enhanced by OsLRR1.</p> <p>Result</p> <p>Through electron microscopy studies using wild type rice plants, OsHIR1 was found to mainly localize to the plasma membrane, with a minor portion localized to the tonoplast. Moreover, the plasma membrane localization of OsHIR1 was enhanced in transgenic rice plants overexpressing its interacting protein partner, OsLRR1. Co-localization of OsHIR1 and OsLRR1 to the plasma membrane was confirmed by double-labeling electron microscopy. Pathogen inoculation studies using transgenic <it>Arabidopsis thaliana </it>expressing either OsHIR1 or OsLRR1 showed that both transgenic lines exhibited increased resistance toward the bacterial pathogen <it>Pseudomonas syringae </it>pv. <it>tomato </it>DC3000. However, <it>OsHIR1 </it>transgenic plants produced more extensive spontaneous hypersensitive response lesions and contained lower titers of the invading pathogen, when compared to <it>OsLRR1 </it>transgenic plants.</p> <p>Conclusion</p> <p>The OsHIR1 protein is mainly localized to the plasma membrane, and its subcellular localization in that compartment is enhanced by OsLRR1. The expression of OsHIR1 may sensitize the plant so that it is more prone to HR and hence can react more promptly to limit the invading pathogens' spread from the infection sites.</p
Impact of Fibronectin Knockout on Proliferation and Differentiation of Human Infrapatellar Fat Pad-Derived Stem Cells
Fibronectin plays an essential role in tissue development and regeneration. However, the effects of fibronectin knockout (FN1-KO) on stem cells’ proliferation and differentiation remain unknown. In this study, CRISPR/Cas9 generated FN1-KO in human infrapatellar fat pad-derived stem cells (IPFSCs) was evaluated for proliferation ability including cell cycle and surface markers as well as stemness gene expression and for differentiation capacity including chondrogenic and adipogenic differentiation. High passage IPFSCs were also evaluated for proliferation and differentiation capacity after expansion on decellularized ECM (dECM) deposited by FN1-KO cells. Successful FN1-KO in IPFSCs was confirmed by Sanger sequencing and Inference of CRISPR Edits analysis (ICE) as well as immunostaining for fibronectin expression. Compared to the GFP control, FN1-KO cells showed an increase in cell growth, percentage of cells in the S and G2 phases, and CD105 and CD146 expression but a decrease in expression of stemness markers CD73, CD90, SSEA4, and mesenchymal condensation marker CDH2 gene. FN1-KO decreased both chondrogenic and adipogenic differentiation capacity. Interestingly, IPFSCs grown on dECMs deposited by FN1-KO cells exhibited a decrease in cell proliferation along with a decline in CDH2 expression. After induction, IPFSCs plated on dECMs deposited by FN1-KO cells also displayed decreased expression of both chondrogenic and adipogenic capacity. We concluded that FN1-KO increased human IPFSCs’ proliferation capacity; however, this capacity was reversed after expansion on dECM deposited by FN1-KO cells. Significance of fibronectin in chondrogenic and adipogenic differentiation was demonstrated in both FN1-KO IPFSCs and FN(–) matrix microenvironment
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