Hydro+Cascade, Flow, the Equation of State, Predictions and Data

A Hydro+Cascade model has been used to describe radial and elliptic flow at the SPS and successfully predicted the radial and elliptic flow measured by the both STAR and PHENIX collaborations . Furthermore, a combined description of the radial and elliptic flow for different particle species, restricts the Equation of State(EoS) and points towards an EoS with a phase transition to the Quark Gluon Plasma(QGP) .Comment: Quark Matter 2001 Procedings. Corrected Fig. 3b for all charged. Some typos fixe

Directional emission of stadium-shaped micro-lasers

The far-field emission of two dimensional (2D) stadium-shaped dielectric cavities is investigated. Micro-lasers with such shape present a highly directional emission. We provide experimental evidence of the dependance of the emission directionality on the shape of the stadium, in good agreement with ray numerical simulations. We develop a simple geometrical optics model which permits to explain analytically main observed features. Wave numerical calculations confirm the results.Comment: 4 pages, 8 figure

On the stability of homogeneous Einstein manifolds II

For any $G$-invariant metric on a compact homogeneous space $M=G/K$, we give a formula for the Lichnerowicz Laplacian restricted to the space of all $G$-invariant symmetric $2$-tensors in terms of the structural constants of $G/K$. As an application, we compute the $G$-invariant spectrum of the Lichnerowicz Laplacian for all the Einstein metrics on most generalized Wallach spaces and any flag manifold with $b_2(M)=1$. This allows to deduce the $G$-stability and critical point types of each of such Einstein metrics as a critical point of the scalar curvature functional.Comment: 27 page

Bismut Ricci flat generalized metrics on compact homogeneous spaces

A generalized metric on a manifold $M$, i.e., a pair $(g,H)$, where $g$ is a Riemannian metric and $H$ a closed $3$-form, is a fixed point of the generalized Ricci flow if and only if $(g,H)$ is Bismut Ricci flat: $H$ is $g$-harmonic and $Ric(g)=\frac{1}{4} H_g^2$. On any homogeneous space $M=G/K$, where $G=G_1\times G_2$ is a compact semisimple Lie group with two simple factors, under some mild assumptions, we exhibit a Bismut Ricci flat $G$-invariant generalized metric, which is proved to be unique among a $4$-parameter space of metrics in many cases, including when $K$ is neither abelian nor semisimple. On the other hand, if $K$ is simple and the standard metric is Einstein on both $G_1/\pi_1(K)$ and $G_2/\pi_2(K)$, we give a one-parameter family of Bismut Ricci flat $G$-invariant generalized metrics on $G/K$ and show that it is most likely pairwise non-homothetic by computing the ratio of Ricci eigenvalues. This is proved to be the case for every space of the form $M=G\times G/\Delta K$ and for $M=SO(8)\times SU(4)/SU(3)$.Comment: 24 pages. Formula for the Ricci curvature in Prop 3.2, (iv) corrected. New (and much simpler) statement for Thm 5.1, (i). New main result on curves in Thm 5.17. Remarks 5.2, 5.9, 5.18 and 5.19 adde

Classification of 7-dimensional Einstein nilradicals II

This paper contains all computations supporting the classification of 7-dimensional Einstein nilradicals given in the article "Classification of 7-dimensional Einstein nilradicals" (arXiv). Each algebra is analyzed in detail here.Comment: 71 pages. Final versio

DART: A 3D Model for Remote Sensing Images and Radiative Budget of Earth Surfaces

Modeling the radiative behavior and the energy budget of land surfaces is relevant for many scientific domains such as the study of vegetation functioning with remotely acquired information. DART model (Discrete Anisotropic Radiative Transfer) is developed since 1992. It is one of the most complete 3D models in this domain. It simulates radiative transfer (R.T.) in the optical domain: 3D radiative budget and remote sensing images (i.e., radiance, reflectance, brightness temperature) of vegetation and urban Earth surfaces, for any atmosphere, wavelength, sun/view direction, altitude and spatial resolution. It uses an innovative multispectral approach (flux tracing, exact kernel, discrete ordinate techniques) over the whole optical domain. Here, its potential is illustrated with the case of urban and tropical forest canopies. Moreover, three recent improvements in terms of functionality and operability are presented: account of Earth/Atmosphere curvature for oblique remote sensing measurements, importation of 3D objects simulated as the juxtaposition of triangles with the possibility to transform them into 3D turbid objects, and R.T. simulation in landscapes that have a continuous topography and landscapes that are non repetitive. Finally, preliminary results concerning two application domains are presented. 1) 2D distribution of the reflectance, brightness temperature and radiance measured by a geostationary satellite over a whole continent. 2) 3D radiative budget of natural and urban surfaces with a DART energy budget (EB) component that is being developed. This new model, called DARTEB, is intended to simulate the energy budget of land surfaces

Internalization and induction of antioxidant messages by microvesicles contribute to the antiapoptotic effects on human endothelial cells

Microvesicles are plasma membrane-derived fragments released from various cell types during activation and/or apoptosis and posses the ability to deliver biological information between cells. Microvesicles generated from T lymphocytes undergoing activation and apoptosis bear the morphogen Sonic Hedgehog, and exert a beneficial potential effect on the cardiovascular system through their dual capacity to increase nitric oxide and reduce reactive oxygen species production. This study investigated the effect of microvesicles on the apoptosis of human umbilical vein endothelial cells triggered by actinomycin D. Microvesicles prevented apoptosis induced by actinomycin D by modulating reactive oxygen species production: during the early phase of apoptosis, microvesicles might act directly as reactive oxygen species scavengers, owing to their ability to carry active antioxidant enzymes, catalase, and isoforms of the superoxide dismutase. Furthermore, their effects were associated with the ability to increase the expression of manganese-superoxide dismutase in endothelial cells, through the internalization process. Interestingly, microvesicles bearing Sonic Hedgehog induced cytoprotection in endothelial cells through the activation of the Sonic Hedgehog pathway. These findings provide additional evidence that microvesicles from T lymphocytes exert their vasculoprotective effects by promoting internalization and induction of antioxidant messages to the endothelial monolayer