3,266 research outputs found
The equation of state at high temperatures from lattice QCD
We present results for the equation of state upto previously unreachable,
high temperatures. Since the temperature range is quite large, a comparison
with perturbation theory can be done directly.Comment: 7 pages, 5 figures, Lattice 200
The nature of the finite temperature QCD transition as a function of the quark masses
The finite temperature QCD transition for physical quark masses is a
crossover. For smaller quark masses a first-order phase transition is expected.
Using Symanzik improved gauge and stout improved fermion action for 2+1 flavour
staggered QCD we give estimates/bounds for the phase line separating the
first-order region from the crossover one. The calculations are carried out on
two different lattice spacings. Our conclusion for the critical mass is for and for lattices.Comment: Talk presented at the XXV International Symposium on Lattice Field
Theory, July 30 - August 4 2007, Regensburg, Germany. 7 pages, 6 figure
Lattice SU(3) thermodynamics and the onset of perturbative behaviour
We present the equation of state (pressure, trace anomaly, energy density and
entropy density) of the SU(3) gauge theory from lattice field theory in an
unprecedented precision and temperature range. We control both finite size and
cut-off effects. The studied temperature window () stretches
from the glueball dominated system into the perturbative regime, which allows
us to discuss the range of validity of these approaches. From the critical
couplings on fine lattices we get T_c/\Lambdamsbar=1.26(7) and use this ratio
to express the perturbative free energy in units. We also determine the
preferred renormalization scale of the Hard Thermal Loop scheme and we fit the
unknown order perturbative coefficient at extreme high temperatures
. We furthermore quantify the nonperturbative contribution to the
trace anomaly using two simple functional forms.Comment: 7 pages, Contribution to the The XXVIII International Symposium on
Lattice Field Theory; June 14 - 19, 2010, Villasimius, Sardinia, Ital
Lattice QCD at non-vanishing density: phase diagram, equation of state
We propose a method to study lattice QCD at non-vanishing temperature (T) and
chemical potential (\mu). We use n_f=2+1 dynamical staggered quarks with
semi-realistic masses on L_t=4 lattices. The critical endpoint (E) of QCD on
the Re(\mu)-T plane is located. We calculate the pressure (p), the energy
density (\epsilon) and the baryon density (n_B) of QCD at non-vanishing T and
\mu.Comment: Contributed to Workshop on Strong and Electroweak Matter (SEWM 2002),
Heidelberg, Germany, 2-5 Oct 200
The QCD equation of state at finite T/\mu on the lattice
We present N_t=4 lattice results for the equation of state of 2+1 flavour
staggered, dynamical QCD at finite temperature and chemical potential. We use
the overlap improving multi-parameter reweighting technique to extend the
equation of state for non-vanishing chemical potentials. The results are
obtained along the line of constant physics. Our physical parameters extend in
temperature and baryon chemical potential upto \approx 500-600 MeV.Comment: 13 pages 9 figures, talk given at Finite Density QCD at Nara, Nara,
Japan, 10-12 July 200
WaSul-Hygro: A diode laser based photoacoustic instrument for airborne measurement of water vapor and total water concentration
Detection of Ser/Thr protein phosphatases in Neurospora crassa
Protein phosphorylation is a frequent posttranslational modification regulating cellular processes in eukaryotes. The phosphate content of a protein is determined by the conflicting activities of protein kinases and phosphatases. Protein phosphatases were divided into Ser/Thr and Tyr specific groups, depending on the phosphorylated residue in the substrate molecules. The former group was further classified based on enzymatic criteria (reviewed in Cohen 1989 Ann. Rev. Biochem. 58:453-508). Protein phosphatase 1 (PP1) is inhibited by two heat stable proteins termed inhibitor-1 and -2. Protein phosphatase 2A is inhibited by nanomolar concentration of the tumor promoter okadaic acid. Protein phosphatase 2B (PP2B) - also called calcineurin - is stimulated by Ca-calmodulin, and protein phosphatase 2C (PP2C) is a Mg2+ dependent enzyme. Molecular cloning of the catalytic subunits revealed that PP1-PP2A-PP2B consist of a highly conserved superfamily of proteins
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