Some higher-order modifications of Newton’s method for solving nonlinear equations

In this paper we consider constructing some higher-order modifications of Newton’s method for solving nonlinear equations which increase the order of convergence of existing iterative methods by one or two or three units. This construction can be applied to any iteration formula, and per iteration the resulting methods add only one additional function evaluation to increase the order. Some illustrative examples are provided and several numerical results are given to show the performance of the presented methods.     

Quantum control and manipulation of multi-color light fields

Quantum control of stationary multi-color (MC) light fields in resonant medium with multi-Λ scheme of atomic transition is proposed. We have found the general analytical solution in the adiabatic limit of quantum evolution resulting from the interaction of the slow probe light with the new fields generated in the nondegenerate multi-wave mixing scheme. We have found a critical condition for the stopping and quantum manipulation of the MC-light fields where the united light group velocity can be reduced down to zero with optimal spectral parameters while preserving the delicate quantum correlations of the initial probe light pulse. The manipulations, which provide the effective transference of quantum probe light to the new multifrequency light fields have been analyzed. The text was submitted by the authors in English.     

Einflu? der Triaden-Konzentration auf die Glastemperatur von Copolymeren. 2. Mitt.

Ohne Zusammenfassung     

Generalization of simulation results practicality of statistical methods

The major purpose of this paper is to evaluate the practical use of statistical techniques in both the generalization or analysis of simulation results, and the design of simulation experiments. This problem is investigated with the help of a real-life system, namely the container terminus of ECT in Rotterdam. This system is modeled by a simulation program. The relationship between the simulation response and its input variables is modeled by a linear regression model: metamodel or auxiliary model. The paper summarizes regression analysis including generalized least squares which might be used for simulation responses with non-constant variances. The validity of the postulated regression metamodel is tested statistically: F- and t-statistics. The selection of the situations to be simulated, is done through experimental design methodology, permitting both quantitative and qualitative factors. The statistical techniques apply not only to simulation but also to real-life experiments.     

Modeling the dispersion of radionuclides released during reactor accidents aboard nuclear-powered vessels

Provenance determinations of pottery by chemical analysis is reviewed and shown to work well. Since pottery is produced from a well homogenized clay paste according to a certain recipe, sharp elemental patterns are expected for a series of products having the same origin. To obtain such patterns when forming compositional groups of pottery, a consideration of experimental errors, a correction for dilution and a choice of only stable elements is necessary. The patterns thus obtained will have low probability of overlap with groups of different origin. Examples for well defined groups of German stonewares and of Mycenaean wares from the Peloponnese are recorded.     

Sliding mode control of a “Soft” 2-DOF Planar Pneumatic Manipulator

This paper presents a sliding mode controller for a “Soft” 2-DOF Planar Pneumatic Manipulator actuated by pleated pneumatic artificial muscle actuators. Since actuator dynamics is not negligible, an approximate model for pressure dynamics was taken into account, which made it necessary to perform full input-output feedback linearization in order to design a sliding mode controller. The design of the controller is presented in detail, and experimental results obtained by implementing the controller are discussed Published in Prikladnaya Mekhanika, Vol. 44, No. 10, pp. 135–144, October 2008.     

Preparation of two uranium glass reference materials for fission-track dating of geological samples

The European Commission produced and certified uranium glass for fission-track dating in 1996 (Reference Material IRMM-540). This material is now out of stock and a project for the preparation of two new reference glasses is underway. The new glasses, containing nominally 15 and 55 mgkg⁻¹ uranium, were prepared from blended oxide powder, and cast using an improved method, which minimised micro-scale defects and optimised the yield. Glass rods were produced which were then cut into discs of 2 mm thickness and 15 mm diameter and subsequently polished.

Uranium homogeneity and fission-track stability are critical properties of the glass. An extensive study was carried out to verify the homogeneity by fission-track counting, investigating both within-disc and between disc effects, and to investigate potential track fading due to thermal annealing. No evidence of uranium heterogeneity was detected. The stability study, using an “isochronous” method, in which all measurements are made at the end of exposure to artificial ageing, is still underway.

The reference material will be certified for isotopic composition (natural), uranium mass fraction and neutron fluence (one disc out of each set of three will be irradiated, together with a mica foil, to induce fission tracks in a certified fluence). The reference materials will be released as IRMM-540R (15 mgkg⁻¹ U) and IRMM-541 (55 mgkg⁻¹ U).     

Investigation of the signaling mechanism and verification of the performance of an electrochemical real-time PCR system based on the interaction of methylene blue with DNA

The operation of an electrochemical real-time PCR system, based on intercalative binding of methylene blue (MB) with dsDNA, has been demonstrated. PCR was performed on a fabricated electrode-patterned glass chip containing MB while recording the cathodic current peak by measuring the square wave voltammogram (SWV). The current peak signal was found to decrease with an increase in the PCR cycle number. This phenomenon was found to be mainly a consequence of the lower apparent diffusion rate of the MB-DNA complex (D(b) = 6.82 × 10(-6) cm(2) s(-1) with 612 bp dsDNA) as compared to that of free MB (D(f) = 5.06 × 10(-5) cm(2) s(-1)). Utilizing this signal changing mechanism, we successfully demonstrated the feasibility of an electrochemical real-time PCR system by accurately quantifying initial copy numbers of Chlamydia trachomatis DNA templates on a direct electrode chip. A standard calibration plot of the threshold cycle (C(t)) value versus the log of the input template quantity demonstrated reliable linearity and a good PCR efficiency (106%) that is comparable to that of a conventional TaqMan probe-based real time PCR. Finally, the system developed in this effort can be employed as a key technology for the achievement of point-of-care genetic diagnosis based on the electrochemical real-time PCR.     

Atomic decomposition of the protein solvation free energy and its application to amyloid-beta protein in water

We report the development of an atomic decomposition method of the protein solvation free energy in water, which ascribes global change in the solvation free energy to local changes in protein conformation as well as in hydration structure. So far, empirical decomposition analyses based on simple continuum solvation models have prevailed in the study of protein-protein interactions, protein-ligand interactions, as well as in developing scoring functions for computer-aided drug design. However, the use of continuum solvation model suffers serious drawbacks since it yields the protein free energy landscape which is quite different from that of the explicit solvent model and since it does not properly account for the non-polar hydrophobic effects which play a crucial role in biological processes in water. Herein, we develop an exact and general decomposition method of the solvation free energy that overcomes these hindrances. We then apply this method to elucidate the molecular origin for the solvation free energy change upon the conformational transitions of 42-residue amyloid-beta protein (Aβ42) in water, whose aggregation has been implicated as a primary cause of Alzheimer's disease. We address why Aβ42 protein exhibits a great propensity to aggregate when transferred from organic phase to aqueous phase.