We discuss the fate of certain tachyonic closed string theories from two perspectives. In both cases our approach involves studying directly configurations with finite negative treelevel cosmological constant. Closed string analogues of orientifolds, which carry negative tension, are argued to represent the minima of the tachyon potential in some cases. In other cases, we make use of the fact, ...

In view of the fact that three kinds of phase transformations, i.e. aneutectoid decomposition β→ α+γ2, an ordering transformation β→ β1, and a martensitic transformation β1→ β' have been observed on isothemlal holding and cooling at different rates from the β region in Cu-Al binary alloys, the author has tried to obtain the T/T/T diagrams in order to show the correlations between these three tr...

Decorrelation of the topological charge in Hybrid Monte Carlo (HMC) simulations of QCD with dynamical fermions is a long standing problem. For staggered fermions an insufficient tunneling rate of the topological charge Qt has been observed [1,2]. For Wilson fermions the tunneling rate is adequate in many cases [3,4]. However on large lattices and for large values of κ near the chiral limit the ...

We put forward a fragile zero watermarking scheme to detect and characterize malicious modifications made to a database relation. Most of the existing watermarking schemes for relational databases introduce intentional errors or permanent distortions as marks into the database original content. These distortions inevitably degrade the data quality and data usability as the integrity of a relati...

silica refractory bricks are used especially in the metallurgical industries, due to desirable properties suchas high melting point, rigidity, and high temperatures strength. in this research, different amount of sicwere added to silica refractory containing different binders such as borax, boric acid, calcium nitride,sodium tri poly phosphate, sodium hexa meta phosphate (shmp) and lime. physic...

Centella asiatica is a tropical medicinal plant with a long history of therapeutic uses, dermal disorders, venous insufficiency and microangiopathy. The substances of therapeutic interest are the saponin-containing triterpene acids and their sugar esters. Two bioactive components, asiatic acid and asiaticoside, were extracted from Centella asiatica using subcritical water as an extraction solve...

We develop a general approach to portfolio optimization taking account of estimation risk and stylized facts of empirical finance. This is done within a Bayesian framework. The approximation of the posterior distribution of the unknown model parameters is based on a parallel tempering algorithm. The portfolio optimization is done using the first two moments of the predictive discrete asset retu...

We describe the results obtained from an improved model for protein folding. We find that a good agreement with the native structure of a 46 residue long, five-letter protein segment is obtained by carefully tuning the parameters of the self-avoiding energy. In particular we find an improved free-energy profile. We also compare the efficiency of multidimensional replica exchange method with the...

The effect of subcritical hadron bubbles on a first-order quark-hadron phase transition is studied. These subcritical hadron bubbles created due to thermal fluctuations introduce a finite amount of phase mixing (quark phase mixed with hadron phase) even at and above the critical temperature. For sufficiently strong transitions, as is expected to be the case for the quark-hadron transition, we s...

CONTEXT Quercetin (QR) is a natural strong antioxidant of the plant origins. It is used for treating conditions of heart and blood vessels including "hardening of arteries" (atherosclerosis), high cholesterol, heart disease, circulation problems, preventing cancer, for treating chronic infections of the prostate, etc. AIMS The aim of this work was to development and study of an acid-free tech...