Event-by-event fluctuations of azimuthal particle anisotropy in Au+Au collisions at square root(sNN) = 200 GeV.

This Letter presents the first measurement of event-by-event fluctuations of the elliptic flow parameter v(2) in Au+Au collisions at square root(s(NN))=200 GeV as a function of collision centrality. The relative nonstatistical fluctuations of the v(2) parameter are found to be approximately 40%. The results, including contributions from event-by-event elliptic flow fluctuations and from azimuthal correlations that are unrelated to the reaction plane (nonflow correlations), establish an upper limit on the magnitude of underlying elliptic flow fluctuations. This limit is consistent with predictions based on spatial fluctuations of the participating nucleons in the initial nuclear overlap region. These results provide important constraints on models of the initial state and hydrodynamic evolution of relativistic heavy ion collisions.

High transverse momentum triggered correlations over a large pseudorapidity acceptance in Au + Au collisions at square root(s(NN)) = 200 GeV.

A measurement of two-particle correlations with a high transverse momentum trigger particle (p(T)(trig) > 2.5 GeV/c) is presented for Au+Au collisions at square root(s(NN)) = 200 GeV over the uniquely broad longitudinal acceptance of the PHOBOS detector (-4 < Delta eta < 2). A broadening of the away-side azimuthal correlation compared to elementary collisions is observed at all Delta eta. As in p+p collisions, the near side is characterized by a peak of correlated partners at small angle relative to the trigger particle. However, in central Au+Au collisions an additional correlation extended in Delta eta and known as the "ridge" is found to reach at least |Delta eta| approximately = 4. The ridge yield is largely independent of Delta eta over the measured range, and it decreases towards more peripheral collisions. For the chosen (p(T)(trig) cut, the ridge yield is consistent with zero for events with less than roughly 100 participating nucleons.

[The antitoxic function of the liver in D-galactosamine poisoning]. / Antitoksicheskaia funktsiia pecheni pri intoksikatsii D-galaktozaminom.

Two intragastric administrations of 500 mg/kg of D-galactosamine reduce the RNA and the cytochrome P-45, and b5 content in the hepatic microsomes of rats; inhibit the activity of aminopyrine-N-demethylase, hexobarbital hydroxylase, aniline-p-hydroxylase, and glutathione-S-transferase; reduce the rate of NADP.H and NAD.H oxidation; accelerate inactivation of cytochrome P-450 to cytochrome P-420; reduce the number of points of hexobarbital binding with N-octilamine, though increase the hemoprotein affinity to these substrates. Destruction of the nucleus, endoplasmic reticulum, and mitochondria occurs in the hepatocytes of D-galactosamine poisoned rats.

System size, energy, and centrality dependence of pseudorapidity distributions of charged particles in relativistic heavy-ion collisions.

We present the first measurements of the pseudorapidity distribution of primary charged particles in Cu+Cu collisions as a function of collision centrality and energy, sqrt[s_{NN}]=22.4, 62.4, and 200 GeV, over a wide range of pseudorapidity, using the PHOBOS detector. A comparison of Cu+Cu and Au+Au results shows that the total number of produced charged particles and the rough shape (height and width) of the pseudorapidity distributions are determined by the number of nucleon participants. More detailed studies reveal that a more precise matching of the shape of the Cu+Cu and Au+Au pseudorapidity distributions over the full range of pseudorapidity occurs for the same N{part}/2A rather than the same N_{part}. In other words, it is the collision geometry rather than just the number of nucleon participants that drives the detailed shape of the pseudorapidity distribution and its centrality dependence at RHIC energies.

System size, energy, pseudorapidity, and centrality dependence of elliptic flow.

This Letter presents measurements of the elliptic flow of charged particles as a function of pseudorapidity and centrality from Cu-Cu collisions at 62.4 and 200 GeV using the PHOBOS detector at the Relativistic Heavy Ion Collider. The elliptic flow in Cu-Cu collisions is found to be significant even for the most central events. For comparison with the Au-Au results, it is found that the detailed way in which the collision geometry (eccentricity) is estimated is of critical importance when scaling out system-size effects. A new form of eccentricity, called the participant eccentricity, is introduced which yields a scaled elliptic flow in the Cu-Cu system that has the same relative magnitude and qualitative features as that in the Au-Au system.

System size and centrality dependence of charged hadron transverse momentum spectra in Au + Au and Cu + Cu collisions at square root of SNN = 62.4 and 200 GeV.

We present transverse momentum distributions of charged hadrons produced in Cu + Cu collisions at square root of SNN = 62.4 and 200 GeV. The spectra are measured for transverse momenta of 0.25 < pT < 5.0 GeV/c at square root of SNN = 62.4 GeV and 0.25 < pT < 7.0 GeV/c at square root of SNN = 200 GeV, in a pseudorapidity range of 0.2 < eta < 1.4. The nuclear modification factor R(AA) is calculated relative to p + p data at both collision energies as a function of collision centrality. At a given collision energy and fractional cross section, R(AA) is observed to be systematically larger in Cu + Cu collisions compared to Au + Au. However, for the same number of participating nucleons, R(AA) is essentially the same in both systems over the measured range of pT, in spite of the significantly different geometries of the Cu + Cu and Au + Au systems.

Centrality dependence of charged hadron transverse momentum spectra in Au+Au collisions from sqrt[s(NN)]=62.4 to 200 GeV.

We have measured transverse momentum distributions of charged hadrons produced in Au+Au collisions at sqrt[s(NN)]=62.4 GeV. The spectra are presented for transverse momenta 0.25

[Hepatotropic action of benzobamil in CCl4 poisoning]. / Gepatotropnoe deistvie benzobamila pri intoksikatsii CCl4.

The administration of an antiepileptic drug--benzobamilum-to rats with CCl4-induced hepatitis prevents the development of liver parenchyma necrosis, promotes the retention of normal enzyme activity in hepatocytes, stimulates the excretory and antitoxic liver functions. The drug has antioxidant properties, inhibits the production of lysophosphatidylcholine and the reduction in phosphatidylcholine content in the liver homogenates but fails to intensify CCl4-induced steatosis.

[The correction with hepatic protectors of structural metabolic disorders in the liver in D-galactosamine poisoning]. / Korrektsiia gepatoprotektorami strukturno-metabolicheskikh narushenii v pecheni pri intoksikatsii D-galaktozaminom.

The hepatoprotective agents silybinin, essentiale and eplir (the complex of phospholipids and caratinoids from the mud) prevent in D-galactosamine-induced intoxication of rats the development of hepatitis, hepatocyte necrosis, a decrease in hepatocytes of the activity of the enzymes of mitochondria and endoplasmic reticulum, labilization of lysosomes. These drugs stimulate D-galactosamine-suppressed antitoxic function of the liver: they increase the contents of RNA, cytochromes P-450, b5, the activity of amidopyrine-D-demethylase, hydroxylases of hexobarbital and aniline, improve the activity of the respiratory chain of microsomes, counteract inactivation of cytochrome P-450 into cytochrome P-420. Essentiale and eplir activate conjugation of xenobiotics with reduced glutathione.

[The effect of eplir on an experimental toxic lesion of the liver]. / Vliianie eplira na toksicheskoe porazhenie pecheni v éksperimente.

A hepatoprotector of phospholipid nature eplir extracted from silt mud was shown to prevent like essentiale in CCl4-hepatitis in rats the development of the liver parenchyma necroses, to promote the maintenance of the normal activity of enzymes in hepatocytes, to stabilize lysosomes, to stimulate the antitoxic and excretory functions of the liver, to reduce hyperfermentemia. The mechanism of action of eplir is determined by the antioxidant properties, a decrease of lysophosphatide formation and the inclusion of phosphatidylcholine in membranes.

Pseudorapidity distribution of charged particles in d+Au collisions at sqrt[sNN]=200 GeV.

The measured pseudorapidity distribution of primary charged particles in minimum-bias d+Au collisions at sqrt[s(NN)]=200 GeV is presented for the first time. This distribution falls off less rapidly in the gold direction as compared to the deuteron direction. The average value of the charged particle pseudorapidity density at midrapidity is |eta|< or =0.6)=9.4+/-0.7(syst) and the integrated primary charged particle multiplicity in the measured region is 82+/-6(syst). Estimates of the total charged particle production, based on extrapolations outside the measured pseudorapidity region, are also presented. The pseudorapidity distribution, normalized to the number of participants in d+Au collisions, is compared to those of Au+Au and p+(-)p systems at the same energy. The d+Au distribution is also compared to the predictions of the parton saturation model, as well as microscopic models.

Centrality dependence of charged-hadron transverse-momentum spectra in d+Au collisions at sqrt[s(NN)]=200 GeV.

We have measured transverse momentum distributions of charged hadrons produced in d+Au collisions at sqrt[s(NN)]=200 GeV. The spectra were obtained for transverse momenta 0.25