127 research outputs found
Effects of Trauma-Hemorrhage and IL-6 Deficiency on Splenic Immune Function in a Murine Trauma Model
Splenic immune function is known to be depressed following hemorrhage. The present study investigates the effects of femoral shaft fracture, isolated or in combination with hemorrhage, on early stage cytokine production capacity of splenocytes and observes the role of IL-6 under these conditions. Male IL-6 knockout (IL-6−/−) and wild-type mice (WT) were randomly divided into three groups: sham (S), isolated femoral fracture (Fx), and femoral fracture + volume controlled hemorrhage (TH-Fx) (n = 6 per group). Animals were sacrificed four hours after induction of hemorrhage and fracture. Cytokine release (TNF-α, IL-6, and IL-10) of isolated and LPS-stimulated splenocytes was determined by cytometric bead array. Femoral fracture with or without hemorrhage caused a suppression of in vitro cytokine production capacity of splenocytes at an early posttraumatic stage in WT and IL-6−/−. In the absence of IL-6, the profile of splenic cytokine secretion is significantly altered, identifying this cytokine as a potential therapeutic target to modulate the posttraumatic immune response
First Observation of Self-Amplified Spontaneous Emission in a Free-Electron Laser at 109 nm Wavelength
We present the first observation of Self-Amplified Spontaneous Emission
(SASE) in a free-electron laser (FEL) in the Vacuum Ultraviolet regime at 109
nm wavelength (11 eV). The observed free-electron laser gain (approx. 3000) and
the radiation characteristics, such as dependency on bunch charge, angular
distribution, spectral width and intensity fluctuations all corroborate the
existing models for SASE FELs.Comment: 6 pages including 6 figures; e-mail: [email protected]
TESLA Technical Design Report Part III: Physics at an e+e- Linear Collider
The TESLA Technical Design Report Part III: Physics at an e+e- Linear
ColliderComment: 192 pages, 131 figures. Some figures have reduced quality. Full
quality figures can be obtained from http://tesla.desy.de/tdr. Editors -
R.-D. Heuer, D.J. Miller, F. Richard, P.M. Zerwa
Trends in autoionization of Rydberg states converging to the 4s threshold in the Kr-Rb⁺-Sr²⁺ isoelectonic sequence: theory and experiment
We have measured the photoabsorption spectra of the Kr-like ions Rb+ and Sr2+ at photon energies corresponding to the excitation of 4s-np resonances using, the dual laser plasma photoabsorption technique. Dramatic changes in the line profiles, with increasing ionization and also proceeding along the Rydberg series of each ion, are observed and explained by the trends in 4s-transition amplitudes computed within a framework of configuration-interaction Pauli-Fock calculations. Total photoionization cross sections show very good agreement with relative absorption data extracted from the measured spectra
Exclusive electroproduction of J/psi mesons at HERA
The exclusive electroproduction of J/psi mesons, ep->epJ/psi, has been
studied with the ZEUS detector at HERA for virtualities of the exchanged photon
in the ranges 0.15<Q^2<0.8 GeV^2 and 2<Q^2<100 GeV^2 using integrated
luminosities of 69 pb^-1 and 83 pb^-1, respectively.The photon-proton
centre-of-mass energy was in the range 30<W<220 GeV and the squared
four-momentum transfer at the proton vertex |t|<1.The cross sections and decay
angular distributions are presented as functions of Q^2, W and t. The effective
parameters of the Pomeron trajectory are in agreement with those found in J/psi
photoproduction. The spin-density matrix elements, calculated from the decay
angular distributions, are consistent with the hypothesis of s-channel helicity
conservation. The ratio of the longitudinal to transverse cross sections,
sigma_L/sigma_T, grows with Q^2, whilst no dependence on W or t is observed.
The results are in agreement with perturbative QCD calculations and exhibit a
strong sensitivity to the gluon distribution in the proton.Comment: 33 pages, 10 figures. Submitted to Nuclear Physics
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