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Laser techniques in acoustically levitated micro droplets

Laser techniques were applied to an acoustically levitated droplet for remote investigation of the diameter, species concentration and temperature of the suspended droplet. To this end, the third and the fourth harmonic of a Nd:YAG laser were used for investigation of elastic, fluorescence and phosphorescence signals from the droplet. The droplet was seeded with thermographic phosphors and acetone

Tectonic response of the central Chilean margin (35-38 degrees S) to the collision and subduction of heterogeneous oceanic crust: a thermochronological study

Along-strike geological segmentation in the Andean chain has been recognized at various scales and is Usually attributed to changes in plate motion vectors, as well as the upper-plate expression of differing subducted slab age, strength and composition. We present new multi-phase Ar-40/Ar-39, apatite fission-track and zircon and apatite (U-Th)/He data from a north-south-oriented traverse between 3

Organic aerosol and global climate modelling: a review

The present paper reviews existing knowledge with regard to Organic Aerosol ( OA) of importance for global climate modelling and defines critical gaps needed to reduce the involved uncertainties. All pieces required for the representation of OA in a global climate model are sketched out with special attention to Secondary Organic Aerosol ( SOA): The emission estimates of primary carbonaceous parti

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

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

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

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

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

Familiarity or conceptual priming – event-related potentials in name recognition

Recent interest has been drawn to the separate components of recognition memory, as studied by event-related potentials (ERPs). In ERPs, recollection is usually accompanied by a late, parietal positive deflection. An earlier, frontal component has been suggested to be a counterpart, accompanying recognition by familiarity. However, this component, the FN400, has alternatively been suggested to ref

Biological monitoring of N-methyl-2-pyrrolidone using 5-hydroxy-N-methyl-2-pyrrolidone in plasma and urine as the biomarker

OBJECTIVES: The aims were to study the toxicokinetics of 5-hydroxy-N-methyl-2-pyrrolidone (5-HNMP) in blood and urine after exposure to N-methyl-2-pyrrolidone (NMP) and to study the suitability of 5-HNMP as a biomarker for assessing NMP exposure. METHODS: Six male volunteers were exposed for 8 hours to NMP concentrations of 0, 10, 25, and 50 mg/m3. Blood and urine were sampled before, during, and

Do nutrient additions alter carbon sink strength of ectomycorrhizal fungi?

Carbon sink strength differences are examined here between ectomycorrhizal fungi in interaction with additions of ammonium and apatite (a phosphorus- and calcium-containing mineral). Pinus muricata associated with Paxillus involutus and four suilloid isolates (Suillus pungens and members of three Rhizopogon section Amylopogon species groups) were used in microcosm nutrient addition experiments. Th

Automated nano-electrospray mass spectrometry for protein-ligand screening by noncovalent interaction applied to human H-FABP and A-FABP

A method for ligand screening by automated nano-electrospray ionization mass spectrometry (nano-ESI/MS) is described. The core of the system consisted of a chip-based platform for automated sample delivery from a 96-well plate and subsequent analysis based on noncovalent interactions. Human fatty acid binding protein, H-FABP (heart) and A-FABP (adipose), with small potential ligands was analyzed.

The CXCL12, periostin and CCL9 genes are direct targets for early B-cell factor (EBF) in OP-9 stroma cells.

The development of blood cells from hematopoietic stem cells in the bone marrow is dependent on communication with bone marrow stroma cells, making these cells central for the appropriate regulation of hematopoiesis. To identify transcription factors that may play a role in gene regulation in stroma cells, we performed comparative gene expression analysis of fibroblastic NIH3T3 cells, unable to su

History and results of the two inter-laboratory round robin endotoxin assay studies on cotton dust

Background In the US cotton industry, airborne cotton dust levels are regulated, and other countries are moving to specify safety limits for airborne endotoxins. There is concern about potential respiratory health hazards associated with agricultural and otherorganic dusts. In laboratories, ranking which samples have high and low levels of endotoxin is usually in good agreement between laboratorie