Multiparameter Polynomial Adaptive Stabilizers

In 1983 Morse proved, for unknown scalar one-dimensional linearsystems, the nonexistence of rational or polynomial universalstabilizers (UAS). In 1983, Nussbaum gave an example of an analyticUAS. In our paper, it is shown that there exist time-invariantpolynomial UAS's with multidimensional gain adaptation. Thedesign procedure is developed for linear, minimum-phase systemsof relative degree one. Convergence of the closed-loop systemis proved. Some numerical simulations are provided.     

Molecular dynamics simulations of a nucleoside analogue of 1,4-dihydro-4-oxoquinoline-3-carboxylic acid synthesized as a potential antiviral agent: Conformational studies in vacuum and in water

Conformational analysis of nucleosides may have direct applications to the structure–activity relationship (SAR) studies and in the design of new drug candidates. Although conformational analysis may be accessed in many different ways, in this work it was performed using molecular dynamics (MD) simulation in order to study the dynamic behavior of a nucleoside derivative of 1,4-dihydro-4-oxoquinoline-3-carboxylic acid, synthesized by our group as a potential antiviral agent. The MD simulation was carried out during 10 ns in vacuum and in a box of water at two different temperatures (i.e., 300 and 600 K) using the AMBER force field. The in vacuum MD simulation results are in agreement with the crystallographic structure and with the DFT calculations of the nucleoside, revealing the anti conformer as the more stable one. The simulation in water, however, shows that both conformers may exist at 300 K, the temperature of the in vivo and in vitro assays, revealing that both the syn and anti conformers should be considered in a MD simulation study of the inhibitor–enzyme complex. Simulations are also in agreement with the NOE experiment, which shows that the anti conformer is the preferential one in DMSO-d6 solution at 298 K.     

Development of solid-phase chemiluminescence immunoassays for digoxin comparing flow injection and sequential injection techniques.

The development of a competitive solid-phase immunoassay for digoxin making use of the acridinium chemiluminescence system is described. Two different instrumental approaches are compared. One is based on a continuous flow system using a peristaltic flow injection analysis pump; the other uses a new sequential injection technique. In both systems a flow cell, consisting of transparent PTFE tubing packed with immobilized antibodies, acts as an immunoreactor. The entire assay, including both the immunoreaction and the chemiluminescence reaction, takes place in this immunoreactor cell. Compared with the flow injection technique, the sequential injection mode showed higher precision, ranging from 2.16 to 5.5% RSD depending on concentration. The total assay time, including regeneration, is less than 8 min with the sequential injection technique. The detection limit for both techniques is in the low femtomole range.     

Asymmetric Information in a Capital Accumulation Differential Game with Spillover and Learning Effects

Journal of Optimization Theory and Applications - This paper considers a capital accumulation game where the installation costs of investments are lowered by the firm’s own capital stock...     

A Synthesis of imidazo- and pyrimido[1,2-g][1,6]naphthyridinones

Arylmethylimidazolines and (3-chlorophenyl)methyl-1,4,5,6-tetrahydropyrimidine amidated 2-chloro-3-pyridinecarbonyl chloride, and potassium t-butoxide cyclized the products to linearly fused, tricyclic imidazo-and pyrimido[1,2-g][1,6]naphthyridinones. Condensation of ethyl 2-chloro-3-pyridinecarboxylate with 2-(phenylmethyl)imidazoline in the presence of sodium methoxide directly formed the isomeric, angularly fused 8,9-dihydro-6-phenylimidazo[1,2-a ] [1,8]naphthyridin-5(7H-one.     

Semiclassical variational calculation of liquid-drop model coefficients for metal clusters

We report on semiclassical density variational calculations for spherical alkali metal clusters in the jellium model. We derive liquid-drop model expansions for total energy, ionisation potential and electron affinity and test the coefficients numerically for clusters with up toN=10⁵ atoms. From the limitN→∞, we obtain excellent agreement with surface tensions and work functions evaluated for an infinite plane metal surface.