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Masked edge effects when measuring diffusion coefficients with the cup method

When diffusion coefficients are measured with the cup method, the exposed area is often less than the area of the sample. Because of this masking effect the measured diffusion coefficient is overestimated. The present article presents simple formulas based on two-dimensional analytical solutions to correct for this in cylindrical cup samples. Different cases of anisotropical diffusion are dealt wi

Oxidative activation of the propolis hapten isoprenyl caffeate

The reactions of isoprenyl caffeate, the strongest allergen known to be present in propolis, with plausible functional groups of proteins were studied. The thiols glutathione and cysteine, which add to isoprenyl caffeate after having been oxidised to the corresponding quinone, served as model substances. The structure of the thiol adducts was determined by spectroscopic methods, addition being fou

Identification of a group of nontuberculous mycobacteria isolated from the South Indian BCG trial area by HPLC

Twenty-five isolates of nontuberculous mycobacteria isolated from the South Indian BCG trial area were analysed by high performance liquid chromatography (HPLC) for mycolic acid pattern. The chromatograms differentiated the isolates into four species, namely M. terrae complex, M. intracellulare, M. parafortuitum and M. fortuitum. Three strains were unidentified, one of which did not show any mycol

Nanosphere induced gene expression in human dendritic cells

The molecular mechanisms of nanosphere-induced mucosal immunization are important to decipher, since this can form the basis for novel approaches in, e.g., nasal vaccination. In this study, we have investigated the effect of nanospheres as antigen carriers on immature human dendritic cells. The results clearly indicate that tetanus toxoid immobilized nanospheres have a direct effect on human monoc

Technique for microwave-induced hyperthermia in superficial human tumours

In order to induce local hyperthermia in superficial tumours a computer system using a 2,450 MHz microwave generator connected to a circular (diameter 90 mm) direct contact applicator was constructed based on invasive temperature control. Small thermistor probes with a diameter of 0.6 mm are inserted in the tumour and surrounding tissues. Eight thermistors can be used simultaneously and one of the

Kinetic investigation of a ruthenium metathesis catalyst

The complex [(IMesH2)(PPh2Cy)Cl2RuCHPh] was synthesised and shown to be an active catalyst in ring-closing metathesis of a diallylmalonate. Its phosphine exchange was investigated in C6D6 using magnetisation transfer 31P NMR spectroscopy and it was found to operate via a dissociative mechanism with k353 = 4.1 ± 0.9 s−1, ΔH‡ = 84 ± 10 kJ mol−1 and ΔS‡ = 4 ± 28 J mol−1 K−1.

Microarrays based on affinity-tagged SCFV antibodies: Sensitive detection of analyte in complex proteomes

Antibody microarray is a novel technology that will allow us to efficiently perform global proteome analysis. Performing rapid and multiplexed analysis on complex proteomes, such as human serum, targeting also low-abundant analytes will, however, place high demands upon the microarray design with respect to logistics, specificity and sensitivity. In this study, we have shown that non-purified affi

Evolving Programs and Solutions Using Genetic Programming with Application to Learning and Adaptive Control

This paper discusses two feasibility studies of Genetic Programming (GP) to the field of control theory, GP being a method inspired from nature where the goal is to create a computer program automatically from high-level statements of problems' requirements. The first feasibility study derives from stability theory and deals with evolving a program that can solve discrete-time Lyapunov equations.

Krein's resolvent formula and perturbation theory

The difference between the resolvents of two selfadjoint extensions of a certain symmetric operator A is described by Krein's resolvent formula. We will prove an analog of Krein's formula in a general framework, apply it to extensions theory, and give a straightforward proof of Krein's formula including the case that A is not necessarily densely defined. We will also present a modification of Krei

Removal of trace contaminants using molecularly imprinted polymers

This work was conducted to study the potential of molecularly imprinted polymers (MIPs) for the removal of oestradiol at trace concentrations (1 ppm - 1 ppb). An MIP synthesised with 17 beta-oestradiol as template was compared to non-imprinted polymers (NIP) synthesised under the same conditions but without template, a commercial C18 extraction phase and granulated activated carbon. At 1 ppb,oestr

Investigation of limiting metabolic steps in the utilization of xylose by recombinant Saccharomyces cerevisiae using metabolic engineering

A Saccharomyces cerevisiae screening strain was designed by combining multiple genetic modifications known to improve xylose utilization with the primary objective of enhancing xylose growth and fermentation in xylose isomerase (XI)-expressing strains. Strain TMB 3045 was obtained by expressing the XI gene from Thermus thermophilus in a strain in which the GRE3 gene coding for aldose reductase was

Immunohistochemical localization of calcitonin receptor-like receptor and receptor activity-modifying proteins in the human cerebral vasculature

Calcitonin gene-related peptide and adrenomedullin belong to a structurally related neuropeptide family and are potent vasodilators expressed in the trigeminovascular system. The molecular identity of receptors for these proteins has only recently been elucidated. Central to functional binding of these neuropeptides is the G-protein-coupled receptor, the calcitonin receptor-like receptor (CRLR), W

Visualization of micropatterned complex biosensor sensing chemistries by means of scanning electrochemical microscopy

Redox hydrogel-based micropatterned complex biosensor architectures, used as sensing chemistries in amperometric ethanol or glucose biosensors, were deposited on gold, graphite or glass. Well-localized immobilization of active hydrogels with variable compositions was achieved by dispensing 100 pl droplets of cocktails containing alcohol or glucose dehydrogenase, redox polymer (PVI(13)dmeOs) and cr

Formoterol inhaled as dry powder or via pressurized metered-dose inhaler in a cumulative dose-response study

Formoterol administered by a dry-powder (DP) capsule inhaler was compared with a pressurized metered-dose inhaler (pMDI) with regard to bronchodilating and systemic effects. The study used a double-blind, crossover, double-dummy technique. Twelve patients with moderate reversible asthma in a stable phase were examined on two separate study days, and the inhalers were given in randomized order. Aft

Wnt-5a signaling in breast cancer metastasis

Breast cancer is the most common form of malignancy affecting women in the Western world. Today, anticancer treatment can control primary breast tumors, but treatment and prevention of metastatic disease still represents a major challenge in the management of breast cancer patients. It has been shown that Wnt-5a plays an important role in breast cancer, since loss of that protein is associated wit

An 8-GHz beamforming transmitter IC in 130-nm CMOS

An 8-GHz beamforming transmitter IC has been designed in a 130-nm CMOS process. Two power amplifiers with independently controllable phase enable the beamforming. The phases are digitally controllable over the full 360° range, which is accomplished by binary weighting of quadrature phase signals in the power amplifiers. The quadrature phase signals are generated by a quadrature voltage controlled