Pusan National University

About: Pusan National University is a education organization based out in Busan, South Korea. It is known for research contribution in the topics: Population & Catalysis. The organization has 24124 authors who have published 45054 publications receiving 819356 citations. The organization is also known as: Busan National University & Pusan University.

The Flavonoid Naringenin Inhibits Dimethylnitrosamine-Induced Liver Damage in Rats

Abstract: Naringenin, a phytoalexin found in grapefruits and tomatoes, has been reported to exhibit a wide range of pharmacological properties. In this study, we investigated the protective effect of naringenin on hepatic injury induced by dimethylnitrosamine (DMN) in rats. Oral administration of naringenin (20 and 50 mg/kg daily for 4 weeks) remarkably prevented the DMN-induced loss in body and liver weights and inhibited the elevation of serum alanine transaminase, aspartate transaminase, alkaline phosphatase, and bilirubin levels. Naringenin also restored serum albumin and total protein levels, and reduced the hepatic level of malondialdehyde. Furthermore, DMN-induced collagen accumulation, as estimated by histological analysis of liver tissue stained with Sirius red, was reduced in the naringenin-treated rats. A reduction in hepatic stellate cell activation, as assessed by α-smooth muscle actin staining, was associated with naringenin treatment. In conclusion, these results demonstrate that naringenin exhibited in vivo hepatoprotective and anti-fibrogenic effects against DMN-induced liver injury. It suggests that naringenin may be useful in preventing the development of hepatic fibrosis.

Production of Σ(1385)± and Ξ(1530)0 in proton–proton collisions at s√= 7 TeV

Abstract: The production of the strange and double-strange baryon resonances (Sigma (1385)(+/-), Xi (1530)(0)) has been measured at mid-rapidity (vertical bar y vertical bar < 0.5) in proton-proton collisions at root s = 7 TeV with the ALICE detector at the LHC. Transverse momentum spectra for inelastic collisions are compared to QCD-inspired models, which in general underpredict the data. A search for the phi (1860) pentaquark, decaying in the Xi pi channel, has been carried out but no evidence is seen.

Numerical Studies of Cosmic-Ray Injection and Acceleration

Abstract: A numerical scheme that incorporates a thermal leakage injection model into a combined gasdynamics and cosmic-ray (CR) diffusion-convection code has been developed. The hydro/CR code can follow in a very cost-effective way the evolution of CR-modified planar quasi-parallel shocks by adopting subzone shock tracking and multilevel adaptive mesh refinement techniques. An additional conservative quantity, S = Pg/ργg−1, is introduced to follow the adiabatic compression accurately in the precursor region, especially in front of strong, highly modified shocks. The "thermal leakage" injection model is based on the nonlinear interactions of the suprathermal particles with self-generated MHD waves in quasi-parallel shocks. The particle injection is followed numerically by filtering the diffusive flux of suprathermal particles across the shock to the upstream region according to a velocity-dependent transparency function that controls the fraction of leaking particles. This function is determined by a single parameter, , which should depend on the strength of postshock wave turbulence but is modeled as a constant parameter in our simulations. We have studied CR injection and acceleration efficiencies during the evolution of CR-modified planar shocks for a wide range of initial shock Mach numbers, M0, assuming a Bohm-like diffusion coefficient. For expected values of the injection process is very efficient when the subshock is strong, leading to fast and significant modification of the shock structure. As the CR pressure increases, the subshock weakens and the injection rate decreases accordingly so that the subshock does not disappear. Although some fraction of the particles injected early in the evolution continue to be accelerated to ever higher energies, the postshock CR pressure reaches an approximate time-asymptotic value because of a balance between fresh injection/acceleration and advection/diffusion of the CR particles away from the shock. In the strong shock limit of M0 30, the injection and acceleration processes are largely independent of the initial shock Mach number for a given , while they are sensitively dependent on M0 for M0 < 30. We conclude that the injection rates in strong parallel shocks are sufficient to lead to rapid nonlinear modifications to the shock structures and that self-consistent injection and time-dependent simulations are crucial to understanding the nonlinear evolution of CR-modified shocks.