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Influence of plasmons on terahertz conductivity measurements

Time-domain terahertz spectroscopy allows measuring the complex conductivity spectrum of materials at frequencies on the order of 1 THz. Typically, terahertz (THz) studies produce conductivity spectra that are different from those predicted by the classical Drude model, especially in nanostructured materials. We claim that plasmon resonances in particles that are small compared to the THz waveleng

Downscaling of GCM forecasts to streamflow over Scandinavia

A seasonal forecasting technique to produce probabilistic and deterministic streamflow forecasts for 23 basins in Norway and northern Sweden is developed in this work. Large scale circulation and moisture fields, forecasted by the ECHAM4.5 model 4 months in advance, are used to forecast spring flows. The technique includes model output statistics (MOS) based on a non-linear Neural Network (NN) app

The IgD-binding domain of the Moraxella IgD-binding protein MID (MID962-1200) activates human B cells in the presence of T cell cytokines.

Moraxella catarrhalis immunoglobulin D (IgD)-binding protein (MID) is an outer membrane protein with specific affinity for soluble and cell-bound human IgD. Here, we demonstrate that mutated M. catarrhalis strains devoid of MID show a 75% decreased activation of human B cells as compared with wild-type bacteria. In contrast to MID-expressing Moraxella, the MID-deficient Moraxella mutants did not b

Influence of laser pulse duration on relativistic channels

A high-power (10 TW) laser is employed to generate relativistic channels in an underdense plasma. The lengths of the channels are measured by imaging the Thomson-scattered light, and the gas densities are determined through the forward Raman scattered light. The laser-pulse parameters are varied and their impact on the channel formation is studied. It is found that increasing the laser pulse durat

Surface forces in solutions containing semiflexible polymers

The influence of intrinsic chain stiffness on surface forces in solutions containing semiflexible polymers is investigated with density functional theory. The solvent is included explicitly, but comparisons are also made with exact results obtained with ideal chains, in the absence of solvent particles. We find that as the intrinsic stiffness increases, the polymers are at intermediate separations

Local Flip Angle Correction for Improved Volume T1-Quantification in Three-Dimensional dGEMRIC Using the Look-Locker Technique

Purpose: To present an evaluation method for three-dimensional Look-Locker (3D-LL) based T1 quantification, calculating correct T1 values independent of local flip angle (FA) variations. The method was evaluated both in phantoms and in vivo in a delayed Gadolinium Enhanced MRI of Cartilage (dGEMRIC) study with 33 subjects. Materials and Methods: T1 was measured with 3D-LL, using both local FA corr

Nanoelectronic pulse generators based on gated resonant tunnelling diodes

We study the operation of a gated resonant tunnel diode placed in an oscillator tank circuit for application as a pulse generator. The gated diode is realized by a metal gate placed 30nm away from a resonant tunnelling double barrier heterostructure, where the gate is used to control the current of the tunnelling diode. A large signal model is developed for the gated resonant tunnelling diode and

Elevated liver enzymes in Turner syndrome during a 5-year follow-up study

Objectives To study the prevalence and incidence of elevated liver enzymes and their relationship with body weight, metabolic factors and other diseases in Turner syndrome (TS). Design Five-year follow-up. Patients Women with TS (n = 218, mean age 33 +/- 13, range 16-71 years) from outpatient clinics at university hospitals in Sweden. Measurements Fasting blood samples for aspartate (AST) and alan

Alexandrium catenella and Alexandrium minutum blooms in the Mediterranean Sea: Toward the identification of ecological niches

Annual recurrent blooms of the toxic dinoflagellates Alexandrium catenella and Alexandrium minutum were detected from 2000 to 2003 in harbours along the Catalan coast. The interrelation study between the occurrence of the blooms and specific external conditions at the study sites demonstrated that different factors are required for the bloom of each Alexandrium species. Concentrations higher than

A family of inexpensive sampling schemes

To improve image quality in computer graphics, antialiazing techniques such as supersampling and multisampling are used. We explore a family of inexpensive sampling schemes that cost as little as 1.25 samples per pixel and up to 2.0 samples per pixel. By placing sample points in the corners or on the edges of the pixels, sharing can occur between pixels, and this makes it possible to create inexpe

Fluorescence polarization as an analytical tool to evaluate galectin-ligand interactions.

Galectins are a family of β-galactose binding lectins associated with functions such as immunological and malignant events. To study the binding affinity of galectins for natural and artificial saccharides and glycoconjugates we have developed an assay using fluorescence polarization. A collection of fluorescein-conjugated saccharides was synthesized and used as probes with galectins-1 and -3 and

The FERRUM Project: New f-value data for FeII and astrophysical applications

We present the FERRUM Project, an international collaboration aiming at a production and evaluation of oscillator strengths (transition probabilities) of selected spectral lines of singly ionized iron group elements, that are of astrophysical relevance. The results obtained include measurements and calculations of permitted and forbidden lines of Fe II. The data have been applied to both emission

Effects of different fertilizer treatments on ectomycorrhizal colonization potential in 2 Scots pine forests in Sweden

Ectomycorrhizal fungal colonization potential was studied in two low-productivity Scots pine (Pinus sylvestris L.) forests in Sweden treated with different fertilizers. Young Pinus sylvestris seedlings were used as baits for ectomycorrhizal fungi for one growing season and the total ectomycorrhizal colonization level and frequencies of different types were recorded. One of the experimental sites h

A circuit framework for robust manifold learning

Manifold learning and nonlinear dimensionality reduction addresses the problem of detecting possibly nonlinear structure in highdimensional data and constructing lower-dimensional configurations representative of this structure. A popular example is the Isomap algorithm which uses local information to approximate geodesic distances and adopts multidimensional scaling to produce lowerdimensional re

Pseudomonas aeruginosa-induced infection and degradation of human wound fluid and skin proteins ex vivo are eradicated by a synthetic cationic polymer

Objectives: Antimicrobial peptides are important effectors of innate immunity. Bacteria display multiple defence mechanisms against these peptides. For example, Pseudomonas aeruginosa releases potent proteinases that inactivate the human cathelicidin LL-37. Hence, in conditions characterized by persistent bacterial colonization, such as in P. aeruginosa-infected skin wounds, there is a need for ef

Regioselective reductive openings of acetals; Mechanistic details and synthesis of fluorescently labeled compounds

Regioselective reductive openings of mixed phenolic-benzylic acetals, using BH3 center dot NMe3 center dot AlCl3, was investigated, and a mechanism where the outcome is directed by the electrostatic potential of the two oxygen atoms is presented. The regioselective acetal opening was used in the synthesis of a fluorescently labeled analogue to antiproliferative xylosides. The fluorescently labeled

Women's perception of changes in the social network after a spinal cord injury

Purpose. To describe how women with a spinal cord injury (SCI) perceived changes in the social network, and how these changes affected their ability to participate in occupation. Method. Thirteen women, aged 25 to 61 years, with a SCI were interviewed twice. The interviews focused on their ability to participate in occupation, their relations with individuals within the social network, and changes

Validation a portable monitoring device for sleep apnea diagnosis in a population based cohort using synchronized home polysomnography

Subject Objective: To assess the accuracy of a portable monitoring device based on peripheral arterial tonometry to diagnose obstructive sleep apnea (OSA). To propose a new standard for limited-channel device validation using synchronized polysomnography (PSG) home recordings and a population-based cohort. Design: Single-night, unattended PSG and Watch_PAT 100 (WP_100). Setting: Home environment.