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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

The CO2 inhibition of terrestrial isoprene emission significantly affects future ozone projections

Simulations of future tropospheric composition often include substantial increases in biogenic isoprene emissions arising from the Arrhenius-like leaf emission response and warmer surface temperatures, and from enhanced vegetation productivity in response to temperature and atmospheric CO2 concentration. However, a number of recent laboratory and field data have suggested a direct inhibition of le

Patterns and dynamics of rest-phase hypothermia in wild and captive blue tits during winter.

We evaluated biotic and abiotic predictors of rest-phase hypothermia in wintering blue tits (Cyanistes caeruleus) and also assessed how food availability influences nightly thermoregulation. On any given night, captive blue tits (with unrestricted access to food) remained largely homeothermic, whereas free-ranging birds decreased their body temperature (T (b)) by about 5 degrees C. This was not an

Grids for scientific computing: Minisymposium abstract

Grid technologies are still evolving, with standards yet to be defined and reliable production-level solutions yet to be found. Nevertheless, Grid already stepped out of the cradle and slowly but steadily finds its way to the world of the modern information technologies. Early testers and adopters of this innovative technology are researchers in various fields of science, primarily those that trad

Observation of Isomeric Decays in the r-Process Waiting-Point Nucleus 130Cd

The gamma decay of excited states in the waiting-point nucleus 130Cd82 has been observed for the first time. An 8+ two-quasiparticle isomer has been populated both in the fragmentation of a 136Xe beam as well as in projectile fission of 238U, making 130Cd the most neutron-rich N=82 isotone for which information about excited states is available. The results, interpreted using state-of-the-art nucl

Altered nucleotide sugar metabolism in Streptococcus thermophilus interferes with nitrogen metabolism

Exopolysaccharide (EPS)-producing Streptococcus thermophilus strains have attracted interest recently, since the EPSs act as natural viscosifiers and texture enhancers of fermented foods. We have previously reported that the low level of EPS production by S. thermophilus LY03 could be improved by altering the activities of enzymes in the central carbon metabolism involved in the nucleotide sugar m

Origin and destination of globules and irregular masses in the gonadotropin cells from the pituitary of the African catfish, Clarias gariepinus: a morphological study

The possible function of globules and irregular membrane-bound masses in the gonadotropin cells of the pituitary of Clarias gariepinus was studied. Strong secretory stimulation led to the disappearance of the secretory granules from gonadotropin cells but globules and irregular masses remained present. Acid phosphatase was detected enzyme-cytochemically in both globules and irregular masses. Radio

Evidence for inhibitory effect of the agonist gaboxadol at human alpha(1)beta(2)gamma S-2 GABA(A) receptors

Gaboxadol (THIP; 4,5,6,7-tetrahydroisoxazolo[5,4-c]pyridin-3-ol) is an agonist at GABA(A) receptors. THIP concentrations (0.01-50 mM) were applied rapidly to Sf9 cells expressing the human alpha(1)beta(2)gamma(2S) GABA(A) receptors. The EC50 values for the peak current in THIP alone or THIP plus 1 muM diazepam were 154 and 53 muM, respectively. In supersaturating THIP (10-50 mM) the rate of curren

Functional relation between corticonuclear input and movements evoked on microstimulation in cerebellar nucleus interpositus anterior in the cat

The functional relation between receptive fields of climbing fibres projecting to the C1, C3 and Y zones and forelimb movements controlled by nucleus interpositus anterior via the rubrospinal tract were studied in cats decerebrated at the pre-collicular level. Microelectrode tracks were made through the caudal half of nucleus interpositus anterior. This part of the nucleus receives its cerebellar