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Extraction of mercaptobenzothiazole compounds from rubber products

At evaluation of contact dermatitis caused by solid material, patch testing is usually performed with the material as such and with extracts of it. In this study, optimization of the extraction technique monitored by quantitative HPLC analysis of the extracted haptens is described for mercaptobenzothiazole derivatives. Several solvents with different properties are included. Acetone has traditiona

Species-specific encystment patterns in three Baltic cold-water dinoflagellates: The role of multiple cues in resting cyst formation

The relationships among cellular nutrient status, environmental conditions (temperature and nutrient availability), and cyst production were studied in batch cultures of three cold-water dinoflagellates (Scrippsiella hangoei, Gymnodinium corollarium, and Woloszynskia halophila) isolated from the Baltic Sea. We tested the effect of increasing temperature while providing nutrient-replete conditions

Antagonistic coevolution under sexual conflict

The theory of sexual conflict predicts that sexual coevolution will be very dynamic, with in principle perpetual evolutionary arms races and chases. These arms races are expected to stop once the costs of conflict adaptations become too high. We argue that this prediction is contingent on specific assumptions about the sexual interaction and the adaptations involved in the arms race. More generall

Optimisation of membrane area and energy requirement in tubular membrane modules

During ultrafiltration (UF), the driving force along the membrane is diminished due to concentration increase and frictional pressure drop. In most applications of ultrafiltration the influence of the frictional pressure drop is negligible. However, when treating concentrated, viscous liquids the frictional pressure drop can reduce the transmembrane pressure (TMP) significantly. The influence of c

Plasminogen binding and activation at the surface of Helicobacter pylori CCUG 17874

The binding of iodine-labelled plasminogen to Helicobacter pylori CCUG 17874 was characterized. Inhibition of the binding was observed after preincubation of H. pylori cells with nonradiolabelled plasminogen, lysine, or the lysine analogue -aminocaproic acid. Fragments of plasminogen, kringles 1 to 3, kringle 4, and mini-plasminogen, were also studied as potential inhibitors. Mini-plasminogen caus

Taxonomy of the Proisotoma complex. Redefinition of genera and description of new species of Scutisotoma and Weberacantha (Collembola, Isotomidae)

The paper provides new information on morphological characters which are useful in generic diagnostics of the Proisotoma complex of Isotomidae. Based on this information, a number of known species are excluded from the redefined Proisotoma s. str. and moved to the genus Scutisotoma Bagnall, 1949, which is again given generic status. The following genera are given more precise definitions: Subisoto

Modulation of l-DOPA-induced abnormal involuntary movements by clinically tested compounds: Further validation of the rat dyskinesia model.

l-DOPA-induced dyskinesia (LID) is a major complication of the pharmacotherapy of Parkinson's Disease. A model of LID has recently been described in rats with unilateral 6-hydroxydopamine (6-OHDA) lesions. In the present study, the model was used in order to compare the efficacies of some clinically available compounds that have shown antidyskinetic effects in nonhuman primate models of LID and/or

Global solutions for quasilinear parabolic systems

We present an approach for proving the global existence of classical solutions of certain quasilinear parabolic systems with homogeneous Dirichlet boundary conditions in bounded domains with a smooth boundary. (C) 2003 Elsevier Inc. All rights reserved.

Information and its use by animals in evolutionary ecology

Information is a crucial currency for animals from both a behavioural and evolutionary perspective. Adaptive behaviour relies upon accurate estimation of relevant ecological parameters; the better informed an individual, the better it can develop and adjust its behaviour to meet the demands of a variable world. Here, we focus on the burgeoning interest in the impact of ecological uncertainty on ad

Structural basis for the changed substrate specificity of Drosophila melanogaster deoxyribonucleoside kinase mutant N64D

The Drosophila melanogaster deoxyribonucleoside kinase (Dm-dNK) double mutant N45D/N64D was identified during a previous directed evolution study. This mutant enzyme had a decreased activity towards the natural substrates and decreased feedback inhibition with dTTP, whereas the activity with 3'-modified nucleoside analogs like 3'-azidothymidine (AZT) was nearly unchanged. Here, we identify the mut

Violaxanthin de-epoxidase, the xanthophyll cycle enzyme, requires lipid inverted hexagonal structures for its activity

Bilayer-forming lipids were shown to be ineffective in sustaining the enzymatic activity of violaxanthin de-epoxidase. On the other hand, non-bilayer-forming lipids, regard-less of their different chemical character, ensured high activity of violaxanthin de-epoxidase, resulting in conversion of violaxanthin to zeaxanthin. Our data indicates that the presence of lipids forming reversed hexagonal st

Almost k-wise independent sample spaces and their cryptologic applications

An almost k-wise independent sample space is a small subset of m bit sequences in which any k bits are “almost independent”. We show that this idea has close relationships with useful cryptologic notions such as multiple authentication codes (multiple A-codes), almost strongly universal hash families and almost k-resilient functions. We use almost k-wise independent sample spaces to construct new

Simultaneous detection of methane, oxygen and water vapour utilising near-infrared diode lasers in conjunction with difference-frequency generation

An all-diode-laser-based spectrometer is used for the simultaneous detection of methane, oxygen and water vapour. This is accomplished using a 760-nm diode laser and a 980-nm diode laser in conjunction with difference-frequency generation to 3.4 mum in a periodically poled lithium niobate crystal. Each of the output wavelengths is resonant with one of the molecular species. Simultaneous recordings

Prophylactic treatment for severe haemophilia: comparison of an intermediate-dose to a high-dose regimen

A multicentre study was performed in Sweden and the Netherlands, comparing effects of two prophylactic regimens in 128 patients with severe haemophilia, born 1970-90. 42 Swedish patients (high-dose prophylaxis), were compared with 86 Dutch patients (intermediate-dose prophylaxis). Patients were evaluated at the date of their last radiological score according to Pettersson. Annual clotting factor c

Transformation networks in innovation alliances - The development of Volvo C70

This paper addresses an important gap in the literature intersection between network theory and networked innovation by developing a theoretical framework on how to leverage learning alliances across extra- and intra-corporate levels to support both exploration and exploitation of innovation to secure its creation and its implementation. A detailed case of the Volvo C70 development is analysed wit

Socioeconomic Inequality in Exposure to Bullying During Adolescence: A Comparative, Cross-Sectional, Multilevel Study in 35 Countries

Objectives. We examined the socioeconomic distribution of adolescent exposure to bullying internationally and documented the contribution of the macroeconomic environment. Methods. We used an international survey of 162305 students aged 11, 13, and 15 years from nationally representative samples of 5998 schools in 35 countries in Europe and North America for the 2001-2002 school year. The survey u

Mortality among 723 948 foreign- and native-born Swedes 1970-1999

Background: Mortality in a population is regarded as an accurate and valid measure of the population's health. There are a few international studies, predominantly cross- sectional, of mortality among all foreign- born compared with an indigenous population, and the results have varied. No Swedish longitudinal study describing and analysing mortality data was found in a literature review. Methods: