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A young afforestation area in Iceland was a moderate sink to CO2 only a decade after scarification and establishment

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

Soluble pilin of Neisseria gonorrhoeae interacts with human target cells and tissue

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

Effects of repeated exposure to 4 ppm nitrogen dioxide on bronchoalveolar lymphocyte subsets and macrophages in healthy men

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)

Serotonin neuron-dependent and -independent reduction of dyskinesia by 5-HT(1A) and 5-HT(1B) receptor agonists in the rat Parkinson model.

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

Is removal of subchondral bone plate advantageous in cemented cup fixation? A randomized RSA study.

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

Monte Carlo simulation of the mean force between two like-charged macroions with simple 1 : 3 salt added

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

Videofluoroscopy in elderly patients with aspiration: importance of evaluating both oral and pharyngeal stages of deglutition

Oropharyngeal functional impairment increases with age so that radiologists frequently are asked to determine the cause of aspiration in elderly patients. Neuromuscular and cognitive impairment often make it difficult to perform and interpret videofluoroscopic deglutition examinations in these patients. We retrospectively reviewed the barium swallow examinations in 50 elderly patients (mean age, 8

Performance analysis and modelling of an OSA gateway

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

Collaborative meta-analysis of individual participant data from observational studies of Lp-PLA(2) and cardiovascular diseases

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

Regional desertification: A global synthesis

The paper presents results on the use of NOAA AVHRR data for desertification monitoring on a regional-global level. It is based on processing of the GIMMS 8 km global NDVI data set. Time series of annually integrated and standardized annual NDVI anomalies were generated and compared with a corresponding rainfall data set (1981-2003). The regions studied include the Mediterranean basin, the Sahel f

Quality assessment for prostate-specific antigen (PSA) in relation to ERSPC: report of the PSA Committee

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

Extending the time range of apatite (U-Th)/He thermochronometry in slowly cooled terranes: Palaeozoic to Cenozoic exhumation history of southeast Sweden

The use of (U-Th)/He thermochronometry in old slowly cooled terranes has long been debated. Hence, studies of natural setting are needed to verify the expected diffusivity behaviour of helium. Our results demonstrate that the (U-Th)/He method can be applicable to samples older than 200 Ma, and that available helium diffusion models can reproduce the results obtained from the age-vs.-depth trends.

Actions seen as demanding in patients with severe dementia during one year of intervention. Comparison with controls

Behaviours, viewed by nurses as demanding, performed by patients with severe dementia were investigated during one year of intervention. Supervised implementation of individually planned care and systematic clinical supervision were implemented on one experimental ward (EW) while another ward (CW) served as control. Each ward had 11 patients. At baseline and after 6 and 12 months of intervention s

Similitude of permeabilities for Ficoll, pullulan, charge-modified albumin and native albumin across the rat peritoneal membrane.

Abstract Aim: Compared to neutral globular proteins, neutral polysaccharides, such as dextran, pullulan and Ficoll, appear hyperpermeable across the glomerular filtration barrier. This has been attributed to an increased flexibility and/or asymmetry of polysaccharides. The present study investigates whether polysaccharides are hyperpermeable also across the continuous capillaries in the rat perito

Do adult and juvenile dunlins Calidris alpina form randomly mixed flocks during fall migration?

Many northerly breeding shorebird species show a separation in timing of adult and juvenile migration. If, in addition to genetic control of migration, learning from experienced conspecifics is advantageous, juveniles should join adult birds during their first fall migration when possible. We here present a method to test if juveniles mix with adults during the period of overlap during southward m

The near and far wake of Pallas' long tongued bat (Glossophaga soricina).

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

Devazepide-induced hyperplasia in the rat liver and bile ducts

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

Relationship of the Hormone-Sensitive Lipase-Mediated Modulation of Cholesterol Metabolism in Individual Compartments of the Testis to Serum Pituitary Hormone and Testosterone Concentrations in a Seasonal Breeder, the Mink (Mustela vison).

The role of cholesterol differs in the two compartments of the testis. In the interstitial tissue, cholesterol is necessary for the synthesis of testosterone, whereas in the seminiferous tubules, membrane cholesterol content in developing germ cells will influence the gametes' fertility. Here we evaluate the hormone-sensitive lipase (HSL) modulation of the cholesterol metabolism in each compartmen