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Electrochemically induced oxidative damage to double-stranded calf thymus DNA adsorbed on gold electrodes

Electrochemically induced oxidative damage to DNA was studied with double-stranded calf thymus DNA immobilized directly on a gold electrode surface. Pre-polarization of the DNA-modified electrodes at +0.5 V versus Ag/AgCl reference electrode, in a free from DNA blank buffer solution, pH 7.4, allowed for subsequent detection of direct electrochemical oxidation of adsorbed on gold DNA, in the potent

Evaluation, Experience and Potential of Gas Turbine Based Cycles with Humidification

Gas turbines, in simple and combined cycle, are common and economically profitable on the power generating market today. Several new cycles have been proposed as future competing technologies, but all studies about these cycles have, so far, been paperwork. The requirements for these new cycles are better efficiency than those of today, provide better flexibility, offer short start up times, less

Rapid Determination of Major and Trace Elements in Geological Material with Proton-Induced X-Ray and Gamma-Ray Emission

The simultaneous detection of proton-induced X-rays and gamma-rays enables rapid determination of both major and trace elements in thick homogeneous samples. Using protons of energy 2.55 MeV, the atomic numbers of the elements detectable with this technique were Z=3, 5, 9, 11–13 from gamma-ray analysis and Z=13–92 from X-ray analysis. Thick target concentrations were determined from a thoroughly m

A new species of Pediobius (Hymenoptera : Eulophidae) from Epilachna (Coleoptera : Coccinellidae) in Costa Rica

A new and morphologically very distinct species of Pediobius from Costa Rica is described. The new species (P. nishidai) is unique among New World species of Pediobius in having the propodeum elongated and extended backwards (i.e. with an elongated nucha). The entire type series (15 females, two males) was reared from a single prepupa of Epilachna mexicana and it has been concluded that the new Pe

First stars X. The nature of three unevolved carbon-enhanced metal-poor stars

Context. On the order of 20% of the very metal-poor stars in the Galaxy exhibit large carbon enhancements. It is important to establish which astrophysical sites and processes are responsible for the elemental abundance patterns of this early Galactic population. Aims. We seek to understand the nature of the progenitors of three main-sequence turnoff Carbon-Enhanced Metal-Poor (CEMP) stars, CS 310

Aspects of the Design of Preparative Chromatography for Purification of Antibodies

The development of biotechnological products is becoming more and more expensive. One type of protein attracting a great deal of attention in the biopharmaceutical industry is antibodies, which was used in this work. The cost of producing antibodies is, however, high, mainly due to the downstream processing, which constitutes 50–80% of the total cost. This work describes model-based methods to des

What does "personality" mean?

The concept of personality is scrutinized as used both in common parlance and in more sophisticated frames of reference. Current multidimensional models are criticized for their reliance on self-descriptive questionnaires and for their lack of a hierarchical dimension, differentiating more or less decisive determinants of behavior. A possible psychoanalytic model is viewed with more benevolence bu

Resolution of 2D Wenner resistivity imaging as assessed by numerical modelling

Modelling of 2D resistivity imaging was done in order to understand the principle resolution of the technique in different geological situations, and for assessing the behaviour of the interpretation methods under controlled circumstances. The Wenner array was used throughout. The results show that the 1D approximation only provides reasonable results in environments with very gradual lateral resi

Random graphs with hidden color

We propose and investigate a unifying class of sparse random graph models, based on a hidden coloring of edge-vertex incidences, extending an existing approach, random graphs with a given degree distribution, in a way that admits a nontrivial correlation structure in the resulting graphs. The approach unifies a number of existing random graph ensembles within a common general formalism, and allows

Islanding detection and connection requirements

This paper reflects how anti-islanding protection has developed with increasing DG penetration. Starting from a local issue it has developed to possibly affect system security. The focus here is on how islanding detection methods and anti-islanding protection settings relate to distribution level and TSO requirements. It is confirmed using field measurements and simulations that the most common pa

Synthesis and Characterization of Diphenyl-2-thienylphosphine Derivatives

The reaction of [Co2{μ-C2(CO2Me)2}(CO)6] with the ligand diphenyl-2-thienylphosphine, PPh2(C4H3S), yields the complexes [Co2{μ-C2(CO2Me)2}(CO)5{PPh2(C4H3S)}] (1) and [Co2{μ-C2(CO2Me)2}(CO)4{PPh2(C4H3S)}2] (2). The related complex [Co3(μ3CMe)(CO)9] reacts with the same ligand to give [Co3(μ3-CMe)(CO)8{PPh2(C4H3S)}] (3) and [Co3(μ3-CMe)(CO)7{PPh2(C4H3S))2] (4). Thermolysis of 1 at 80°C leads to part

Streptococcal M protein and human C4BP

Antigenic variation of surface proteins allows microorganisms to evade the immune system of the infected host. This phenomenon represents an apparent paradox, because the variable protein must retain an important function, while its antigenic properties vary extensively. The surface associated M protein of Streptococcus pyogenes, a common human pathogen, exhibits antigenic variation due to an N-te

Low serum concentration of all-trans and 13-cis retinoic acids in patients treated with phenytoin, carbamazepine and valproate. Possible relation to teratogenicity

All-trans retinoic acid deficiency resulting from ethanol's interference with the synthesis of all-trans retinoic acid from retinol was recently suggested to cause the malformations of the fetal alcohol syndrome. Phenytoin, carbamazepine and valproate, might be teratogenic because they lower the concentration of all-trans retinoic acid in serum, by inducing the enzyme systems in the liver responsi

Dynamic Programming and Time-Varying Delay Systems

This thesis is divided into two separate parts. The first part is about Dynamic Programming for non-trivial optimal control problems. The second part introduces some useful tools for analysis of stability and performance of systems with time-varying delays. The two papers presented in the first part attacks optimal control problems with finite but rapidly increasing search space. In the first pap