Increasing the stability of an enzyme toward hostile organic solvents by directed evolution based on iterative saturation mutagenesis using the B-FIT method

Mutants of the lipase from Bacillus subtilis, previously engineered for enhanced thermostability using directed evolution based on the B-FIT method, show significantly increased tolerance to hostile organic solvents.     

Reactions of acetonitrile coordinated to a nitrosylruthenium complex with H2O or CH(3)OH under mild conditions: structural characterization of imido-type complexes

The reaction of cis-[Ru(NO)(CH(3)CN)(bpy)(2)](3+) (bpy = 2,2'-bipyridine) in H(2)O at room temperature proceeded to afford two new nitrosylruthenium complexes. These complexes have been identified as nitrosylruthenium complexes containing the N-bound methylcarboxyimidato ligand, cis-[Ru(NO)(NH=C(O)CH(3))(bpy)(2)](2+), and methylcarboxyimido acid ligand, cis-[Ru(NO)(NH=C(OH)CH(3))(bpy)(2)](3+), formed by an electrophilic reaction at the nitrile carbon of the acetonitrile coordinated to the ruthenium ion. The X-ray structure analysis on a single crystal obtained from CH(3)CN-H(2)O solution of cis-[Ru(NO)(NH=C(O)CH(3))(bpy)(2)](PF(6))(3) has been performed: C(22)H(20.5)N(6)O(2)P(2.5)F(15)Ru, orthorhombic, Pccn, a = 15.966(1) A, b = 31.839(1) A, c = 11.707(1) A, V = 5950.8(4) A(3), and Z = 8. The structural results revealed that the single crystal consisted of 1:1 mixture of cis-[Ru(NO)(NH=C(O)CH(3))(bpy)(2)](2+) and cis-[Ru(NO)(NH=C(OH)CH(3))(bpy)(2)](3+) and the structural formula of this single crystal was thus [Ru(NO)(NH=C(OH(0.5))CH(3))(bpy)(2)](PF(6))(2.5). The reaction of cis-[Ru(NO)(CH(3)CN)(bpy)(2)](3+) in dry CH(3)OH-CH(3)CN at room temperature afforded a nitrosylruthenium complex containing the methyl methylcarboxyimidate ligand, cis-[Ru(NO)(NH=C(OCH(3))CH(3))(bpy)(2)](3+). The structure has been determined by X-ray structure analysis: C(25)H(29)N(8)O(18)Cl(3)Ru, monoclinic, P2(1)/c, a = 13.129(1) A, b = 17.053(1) A, c = 15.711(1) A, beta = 90.876(5) degrees, V = 3517.3(4) A(3), and Z = 4.     

Properties of glass-fiber reinforced composites based on liquid diglycidyl ether of bisphenol-c-epoxy resin

Glass-fiber reinforced epoxy composites were fabricated from the matrix resin liquid diglycidyl ether of bisphenol-C (DGEBC) using various amines as curing agents with and without fortifier (20 phr). The epoxy laminates were evaluated for their mechanical properties, such as flexural strength, interlaminar shear strength (ILSS), tensile strength and shore-D hardness. Dielectric properties, such as the dielectric constant, tan δ, dielectric loss and the resistivity of the laminated samples, were measured. The effect of the chemical reagents on the mechanical properties (i.e. flexural strength, lLSS) was also studied.     

On unified fractional integral operators

The present paper is in continuation to our recent paper [6] in these proceedings. Therein, three composition formulae for a general class of fractional integral operators had been established. In this paper, we develop the Mellin transforms and their inversions, the Mellin convolutions, the associated Parseval-Goldstein theorem and the images of the multivariableH-function together with applications for these operators. In all, seven theorems and two corollaries (involving the Konhauser biorthogonal polynomials and the Jacobi polynomials) have been established in this paper. On account of the most general nature of the polynomials S _n ^m [x] and the multivariableH-function whose product form the kernels of our operators, a large number of (new and known) interesting results involving simpler polynomials and special functions (involving one or more variables) obtained by several authors and hitherto lying scattered in the literature follow as special cases of our findings. We give here exact references to the results (in essence) of seven research papers which follow as simple special cases of our theorems.     

Finite analytic boundary condition for a higher‐order finite analytic scheme

A higher‐order finite analytic scheme based on one‐dimensional finite analytic solutions is used to discretize three‐dimensional equations governing turbulent incompressible free surface flow. In order to preserve the accuracy of the numerical scheme, a new, finite analytic boundary condition is proposed for an accurate numerical solution of the partial differential equation. This condition has higher‐order accuracy. Thus, the same order of accuracy is used for the boundary. Boundary conditions were formulated and derived for fluid inflow, outflow, impermeable surfaces and symmetry planes. The derived boundary conditions are treated implicitly and updated with the solution of the problem. The basic idea for the derivation of boundary conditions was to use the discretized form of the governing equations for the fluid flow simplified on the boundaries and flow information. To illustrate the influence of the higher‐order effects at the boundaries, another, lower‐order finite analytic boundary condition, is suggested. The simulations are performed to demonstrate the validity of the present scheme and boundary conditions for a Wigley hull advancing in calm water. Copyright © 2005 John Wiley & Sons, Ltd.     

A simulated annealing based solution approach for the two-layered location registration and paging areas partitioning problem in cellular mobile networks

This paper presents a mathematical model and simulated annealing based solution approach for finding optimal location updates and paging area configuration for mobile communication networks. We use a two-layered zone-based location registration and paging scheme in which the costs of location updates and paging signaling traffic are reduced by introducing a two-step paging process. The location updates and paging procedures in a two-layered scheme are first described, and an approximation of the measure required for calculating the paging-related signaling volume is provided based on assumptions of cell shapes and mobile stations’ movement patterns. A simulated annealing (SA)-based solution method is devised along with a greedy heuristic, and computational experiments are conducted to illustrate the superiority of the proposed SA-based method over other solution methods.     

Search for new physics at a super-<Emphasis Type="Italic">B</Emphasis> factory

The importance of a super-B factory in the search for new physics, in particular, due to CP-odd phase(s) from physics beyond the standard model is surveyed. The first point to emphasize is that we now know how to directly measure all three angles of the unitarity triangle very cleanly, i.e. without theoretical assumptions with irreducible theory error ≲1%. However, this requires much more luminosity than is currently available atB-factories. Direct searches via penguin-dominated hadronic modes as well as radiative, pair-leptonic and semi-leptonic decays are also discussed. Null tests of the SM are stressed as these will play a crucial role especially if the effects of BSM phase(s) onB-physics are small.     

Theoretical study of 2 X 2 element planar array of equilateral triangular patch microstrip antenna in plasma medium

The radiation properties of 2 X 2 element planar array of equilateral triangular patch microstrip antenna in plasma medium are studied. The array factor and far-zone EM-mode and P-mode radiation fields of the array geometry are derived using vector wave function techniques and pattern multiplication approaches. The total field patterns and various characteristics of pattern such as half power beam width (HPBW), first null beam width (FNBW) and direction of maximum radiation are computed for two different values of progressive phase excitation difference between the elements. The results of this array geometry are obtained both in plasma medium and in free space and compared with those of single element equilateral triangular patch microstrip antenna.     

Gluon condensate and the interquark potential

We construct a potential for qurkonium systems using as the basic ingredients the gluon condensate, i.e., 〈0∥G_μν^aG_μν^a∥0〉 ≠ 0 to incorporate nonperturbative effects and using quark screening. The potential is able to account satisfactorily for the s$\text{s}$, c$\text{c}$ and b$\text{b}$ bound states with a flavor independent, essentially constant value for the effective coupling constant $\text{(}\text{α}{}_{\mathrm{<mtext>S</mtext>}}\text{≈ 0.45)}$. We also investigate heavier quark systems with the constant $\text{α}{}_{\mathrm{S}}$ and find that for quark mass ? 20 GeV the potential is essentially coulombic.     

Internal conversion coefficients ofM4 transitions in125m, 127m, 129mTe decay

The internal conversion coefficients have been measured using a high resolution low energy Ge(Li) detector for the followingM4 transitions:¹²⁵Te: 109.27keV transitionα _T =357±11; RG method,¹²⁷Te: 88.26 keV transitionα _T =484±23; XPG method,¹²⁹Te: 105.50keV transitionα _T =213±10; XPG method. It is observed that these values are lower by 2.5–3.6% as compared with Hager and Seltzer's calculations. A comparison between experimental and theoreticalα _T andα _T values for elevenM4 transitions shows that the experimental values are systematically lower.