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Accelerator mass spectrometry - an overview

The technique of accelerator mass spectrometry (AMS) has spread worldwide since its first demonstration 25 years ago. The equipment used today is very diverse and dedicated accelerators as well as old "nuclear physics machines" can be found in the nearly 50 AMS laboratories today. The most widely spread application of AMS is for radiocarbon dating. However, AMS with C-14 as well as with other long

Effects of data uncertainty in Swedish critical load assessment for forest soils.

The effects of input data uncertainty on the critical loads and exceedance estimates for Swedish forest soils was assessed using Monte Carlo simulations of the PROFILE model. The study focuses on the effects of data uncertainty on the 5%-ile critical load at 150 × 150 km resolution and the 95%-ile exceedance at 150 × 150 km and 50 × 50 km resolution. The results indicate that data uncertainty limi

Inhibition of macropinocytosis blocks antigen presentation of type II collagen in vitro and in vivo in HLA-DR1 transgenic mice

Professional antigen-presenting cells, such as dendritic cells, macrophages and B cells have been implicated in the pathogenesis of rheumatoid arthritis, constituting a possible target for antigen-specific immunotherapy. We addressed the possibility of blocking antigen presentation of the type II collagen (CII)-derived immunodominant arthritogenic epitope CII259-273 to specific CD4 T cells by inhi

Development of allergy to laboratory animals is associated with particular Gm and HLA genes

To find out whether IgG genes are involved in atopy we studied 26 of 101 laboratory technicians who had developed laboratory animal allergy (LAA). The genes for the constant region of the heavy chains of IgG subclasses were analyzed by serum Gm allotypes, representing products on allelic level of the IGHCG1, IGHCG2 and IGHCG3 on chromosome 14q32. There was a significantly increased frequency of th

A bit-serial CMOS digital IF-filter for mobile radio using an on-chip clock

A chip for digital intermediate frequency filtering is introduced. The filter is intended move most of the analog intermediate frequency filtering to the digital domain in systems like the American mobile radio system (IS-54). It is a wave digital lattice filter realized with bit-serial arithmetic. Furthermore, a technique for local clocks on chip is presented. The method is based on a ring oscill

Shear-Induced Transitions between a Planar Lamellar Phase and Multilamellar Vesicles: Continuous versus Discontinuous Transformation.

The shear-induced transitions between an oriented lamellar phase and shear-induced multilamellar vesicles (MLVs) in a nonionic surfactant system were studied by deuterium rheo-NMR spectroscopy as a function of time in start-up experiments at several temperatures and shear rates. By starting from an initial state of oriented lamellae and observing the transformation to the final steady state of MLV

Pragmatic comparison of beta(2)-agonist side effects within the worldwide atosiban versus beta agonists study

Objective: While beta(2)-agonists for the acute treatment of preterm labour unequivocally reduce the odds of delivery within 48 hand 7 days, they have been associated with substantial maternal and fetal side effects. We aimed to compare side effect profiles of beta(2)-agonist tocolytics. Study design: Pragmatic comparison of ritodrine, salbutamol and terbutaline from re-analysis of data obtained w

Characterization of recombinant amino-terminal NC4 domain of human collagen IX - Interaction with glycosaminoglycans and cartilage oligomeric matrix protein

The N-terminal NC4 domain of collagen IX is a globular structure projecting away from the surface of the cartilage collagen fibril. Several interactions have been suggested for this domain, reflecting its location and its characteristic high isoelectric point. In an attempt to characterize the NC4 domain in more detail, we set up a prokaryotic expression system to produce the domain. The purified

Male Discrimination of Female Mucous Trails Permits Assortative Mating in a Marine Snail Species

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

Signaling via the Tgf-beta type I receptor Alk5 in heart development

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

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

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

Identification of the [202]3/2 deformed band in mirror nuclei Mg-25 and Al-25 and implications for unstable nuclei

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

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)

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

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