Recent research has shown the potential for nonallopatric speciation, but we lack an adequate understanding of the mechanisms of prezygotic barriers and how these evolve in the presence of gene flow. The marine snail Littorina saxatilis has distinct ecotypes in different shore microhabitats. Ecotypes hybridize in contact zones, but gene flow is impeded by assortative mating. Earlier studies have s

Trophic factors secreted both from the endocardium and epicardium regulate appropriate growth of the myocardium during cardiac development. Epicardially-derived cells play also a key role in development of the coronary vasculature. This process involves transformation of epithelia] (epicardial) cells to mesenchymal cells (EMT). Similarly, a subset of endocardial cells undergoes EMT to form the mes

This study reports on three years (2004-2006) of measurements of net ecosystem exchange (NEE) over a young Siberian larch plantation in Iceland established on previously grazed heathland pasture that had been scarified prior to planting. The study evaluated the variation of NEE and its component fluxes, gross primary production (GPP) and ecosystem respiration (R-e), with the aim to clarify how cli

5-HT(1) receptor agonists have been shown to reduce abnormal involuntary movements (AIMs) in the rat and monkey models of l-DOPA-induced dyskinesia. Different mechanisms have been proposed to underlie this effect. Activation of pre-synaptic 5-HT(1) receptors has been suggested to inhibit dysregulated release of dopamine from the serotonin terminals, and thus, abnormal activation of striatal dopami

There is uncertainty regarding whether and how the subchondral bone plate should be treated during acetabular preparation for cemented cup fixation in a total hip arthroplasty. We hypothesized that removing the bone plate would improve the cement-bone interface without jeopardizing the initial cup stability, and therefore, be advantageous to long-term cup survival. We randomized 50 patients with p

Fifty years after its prediction, the highest-lying [ 2 0 2] 3) 2 orbit among the six Nilsson single-particle orbits originating from the sd shell in prolately deformed nuclei and the rotational band on this orbit were identified. The band members were observed in Al-25 at excitation energies of 6-7.5MeV in a high-resolution Mg-25(He-3,t) charge-exchange reaction at 0 degrees having a strong selec

Pili of Neisseria gonorrhoeae are phase-variable surface structures that mediate adherence to host target cells. Each pilus is composed of thousands of major pilus subunits, pilins, pilus-associated protein PilC, and possibly other components. Piliated and nonpiliated gonococcal clones may secrete a soluble smaller pilin (S-pilin) that is cleaved after amino acid 39 of the mature pilin protein. He

Following the basal descriptive studies of the bronchoalveolar inflammatory cell response induced by single exposure with nitrogen dioxide (NO2) in man, it was considered important to clarify the cell response to repeated exposure with NO2. This investigation was, therefore, undertaken with bronchoalveolar lavage (BAL) 3 weeks before and 24 h after six repeated exposures with 4 ppm NO2 (7 mg.m-3)

The mean force and the potential of the mean force between two like- harged macroions with monovalent counterions and added simple 1:3 salt described within the primitive model and confined in a cylindrical cell have been investigated by Monte Carlo simulations. Without additional salt, a strongly repulsive mean force was obtained at all macroion separations, consistent with a stable solution of m

It is foreseen that you in the future should be able to use the same services independent of where you are positioned or which terminal that is used. The open service architectures provide these opportunities. Open Service Access (OSA) is an example of such an architecture and it is part of the specification delivered by 3GPP. This paper explains the OSA architecture and presents a model of an OSA

Background A large number of observational epidemiological studies have reported generally positive associations' between circulating mass and activity levels of lipoprotein-associated phospholipase A(2) (Lp-PLA(2)) and the risk of cardiovascular diseases. Few studies have been large enough to provide reliable estimates in different circumstances, such as in different subgroups (e.g., by age group

Objective To assess the application of a quality control scheme for total prostate-specific antigen (PSA) as used for participants of the European Randomized Study for Screening of Prostate Cancer (ERSPC) during 1996-2002. Methods From 1996, the first complete year being 1997, an external scheme was organized by the Dutch Quality Assessment Foundation especially for the ERSPC. This scheme consists

The wake structures of a bat in flight have a number of characteristics not associated with any of the bird species studied to this point. Unique features include discrete vortex rings generating negative lift at the end of the upstroke at medium and high speeds, each wing generating its own vortex loop, and a systematic variation in the circulation of the start and stop vortices along the wingspa

Cholecystokinin (CCK) is a potent stimulus of pancreatic enzyme secretion and growth and is known to influence the flow of biliary secretions. It has also been suggested as a trophic stimulus of the biliary tract and liver, but confirmatory studies are lacking. The aim of the present experiment was to study the effects on the rat liver and biliary tract of long-term stimulation of CCK-8S and the C

Diagnosing clinical dementia is based on an assessment of different variables, such as the patient's medical history, known risk factors, and biochemical features. Partial least squares discriminant analysis was used to evaluate variables of importance for diagnosing dementia in a clinical dementia population. Polymorphism for genotypes of glutathione S-transferase (GST) and sulfotransferase 1A1,

The aim of this study was to investigate the effect of absent CD40-CD40 ligand interactions in patients with X-linked hyper-IgM syndrome (XHIGM) on the generation of Th1 and Th2 immunity. Whole blood from patients and sex- and age-matched controls was stimulated with phorbol myristate acetate (PMA) and calcium ionophore A23187 in the presence of Brefeldin A. After 5 h, cellular production of inter