Nanosecond scale molecular dynamics simulations have been performed on antiparallel Greek key type d(G7) quadruplex structures with different coordinated ions, namely Na+ and K+ ion, water and Na+ counter ions, using the AMBER force field and Particle Mesh Ewald technique for electrostatic interactions. Antiparallel structures are stable during the simulation, with root mean square deviation va...

The E864 experiment at BNL requires a beam counter and multiplicity detector system that can perform at an incident beam rate of 10 Au ions per second. We have developed and tested a 150 m thick quartz Cherenkov beam counter and a scintillator based multiplicity-trigger counter during the rst run of this experiment in 1994. We obtained a time resolution of 78 ps for the beam counter at an incid...

– The Poisson-Boltzmann approach gives asymptotically exact counter-ion density profiles around charged objects in the weak-coupling limit of low valency and high temperature. In this paper we derive, using field-theoretic methods, a theory which becomes exact in the opposite limit of strong coupling. Formally, it corresponds to a standard virial expansion. Long-range divergences, which render ...

A series of p-ammo carbonyl compounds containing coumann (4a-h) and benzofuran (6a-i) moieties was synthesized by a three component Mannich reaction of 3-acetyl-2//-chromen-2-one (1) or l-(l-benzofuran-2-yl) ethanone (5) with p-substjiuied aromatic aldehydes (2ag) and aromatic amines (3a-b) in the presence of cerric ammonium nitrate as a catalyst The newly synthesized compounds were screened fo...

2,4,6-Trinitrotoluene (TNT) transformation by the yeast strain Yarrowia lipolytica AN-L15 was shown to occur via two different pathways. Direct aromatic ring reduction was the predominant mechanism of TNT transformation, while nitro group reduction was observed to be a minor pathway. Although growth of Y. lipolytica AN-L15 was inhibited initially in the presence of TNT, TNT transformation was o...

The extracellular calcium (Ca(2+)(o))-sensing receptor (CaR) recognizes and responds to (i.e., "senses") Ca(2+)(o) as its principal physiological ligand. In the present studies, we document that the CaR is activated not only by extracellular calcium ions but also by amino acids, establishing its capacity to sense nutrients of two totally different classes. l-Amino acids, especially aromatic ami...

Aromatic and heterocyclic amines are a major class of chemical mutagens and carcinogens. The toxicity of these compounds is a consequence of their metabolic activation. The best-characterized enzymatic pathways for aromatic amine activation lead to the formation of reactive esters such as N-acetoxyarylamines, which are believed to be precursors of short-lived nitrenium ions. In the 1960s, nitre...

The solvent extraction of rare earth metal ions from nitrate solutions by 5.11.17.23-tetra-tert-butyl-25,27-bis(diethylcarbamoylmethoxy)-26,28-dihydroxycalix[4]arene (L) in 1,2-dichloroethane has been investigated. The alalysis of the extraction equilibrium obtained from a mixture of La3+, Eu3+, Er3+ and Y3+ revealed that the extracted species hav...