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Remarkable variability in morphology, hygroscopicity and optical properties of soot aerosols during internal mixing in the atmosphere.

The atmospheric effects of soot aerosols include interference with radiative transfer, visibility impairment, and alteration of cloud formation and are highly sensitive to the manner by which soot is internally mixed with other aerosol constituents. We present experimental studies to show that soot particles acquire a large mass fraction of sulfuric acid during atmospheric aging, considerably alte

Under the influence of alcohol: The effect of ethanol and methanol on lipid bilayers

Extensive microscopic molecular dynamics simulations have been performed to study the effects of short-chain alcohols, methanol and ethanol, on two different fully hydrated lipid bilayer systems (POPC and DPPC) in the fluid phase at 323 K. It is found that ethanol has a stronger effect on the structural properties of the membranes. In particular, the bilayers become more fluid and permeable: ethan

Human brain activity associated with audiovisual perception and attention

Coherent perception of objects in our environment often requires perceptual integration of auditory and visual information. Recent behavioral data suggest that audiovisual integration depends on attention. The current study investigated the neural basis of audiovisual integration using 3-Tesla functional magnetic resonance imaging (fMRI) in 12 healthy volunteers during attention to auditory or vis

The proteoglycans aggrecan and Versican form networks with fibulin-2 through their lectin domain binding

Aggrecan, versican, neurocan, and brevican are important components of the extracellular matrix in various tissues. Their amino-terminal globular domains bind to hyaluronan, but the function of their carboxyl-terminal globular domains has long remained elusive. A picture is now emerging where the C-type lectin motif of this domain mediates binding to other extracellular matrix proteins. We here de

Eating difficulties in relation to gender, length of stay, and discharge to institutional care, among patients in stroke rehabilitation.

PURPOSE: To describe and compare eating difficulties from admission to discharge, with regard to length of stay (LOS) and discharge to institutional care, as well as in relation to gender. METHOD: Patients, aged 65 or above, admitted for stroke rehabilitation, having at least one eating difficulty were observed (n =108) as regards to eating on admission and at discharge. Analysis followed earlier

The normalizer splitting conjecture for p-compact groups

Let X be a p-compact group, with maximal torus BT-->BX, maximal torus normalizer BN and Weyl group W_X. We prove that for an odd prime p, the fibration BT --> BN --> BW_X has a section, which is unique up to vertical homotopy.

Sex ratio variation and sex determination in the mallee dragon, Ctenophorus fordi

Recent evidence suggests that many Australian agamids show temperature-dependent sex determination (TSD) with variation in sex determining mechanisms among closely related taxa. However, as shown in other vertebrates, sex ratios can also be influenced by genetic or phenotypic differences among females in their propensity to produce sons or daughters, and these influences might confound any thermal

Polyamine dependence of normal cell-cycle progression

The driving force of the cell cycle is the activities of cyclin-dependent kinases (CDKs). Key steps in the regulation of the cell cycle therefore must impinge upon the activities of the CDKs. CDKs exert their functions when bound to cyclins that are expressed cyclically during the cell cycle. Polyamine biosynthesis varies bicyclically during the cell cycle with peaks in enzyme activities at the G(

Alcohol involvement in Swedish University freshmen related to gender, age, serious relationship and family history of alcohol problems.

Aim: The primary aim of this study was to describe alcohol involvement in relation to gender and different age cohorts among freshmen at two Swedish universities. The secondary aim was to investigate whether the results were related to a likelihood of students being in serious relationships and/or had a first-degree relative with alcohol problems. Methods: Two complete cohorts of university freshm

Embankment dam seepage evaluation from resistivity monitoring data

Methods for monitoring seepage are important for the safety of embankment dams. Increased seepage may be associated with internal erosion in the dam and internal erosion is one of the main reasons for dam failures. Internal erosion progresses inside the dam and is difficult to detect by conventional methods. Therefore there is a need for new or improved methods. The resistivity method is a non-des

Emerging biomarkers: New directions and clinical applications

This article summarizes content proceedings of a symposium held at the 2004 Research Society on Alcoholism Scientific Annual Meeting in Vancouver, Canada. The chairs were Friedrich M. Wurst and Raye Litten. The presentations were (1) Introduction, by Raye Litten; (2) Direct Ethanol Metabolites-On the Threshold From Science to Routine Use, by Friedrich M. Wurst; (3) Sialic Acid Index of Plasma Apol

Electronic structure of Li-inserted V6O13 battery cathodes: Rigid band behavior and effects of hybridization

Resonant soft x-ray emission (SXE) spectroscopy was used to study the electronic structure of LixV6O13 battery cathodes. We observe that the V 3d-bands Of V6O13 exhibit a rather rigid behavior. Upon lithiation, electrons enter the top of the valence band and add intensity to the corresponding part of the V L-emission spectrum without significantly distorting the lower lying bands. We perform ab in

Polysaccharide characterization by flow field-flow fractionation-multiangle light scattering: Initial studies of modified starches

Chemically modified starches are commonly used for various purposes. Depending on the type of derivatization, a chemical degradation of the original polymeric structure may occur, resulting in a change of molar mass. It is therefore always of interest to know the molar mass and possibly the conformation of the derivative. Four commercially available hydroxypropyl and hydroxyethyl modified starches

Preparation of molecularly imprinted polymers in supercritical carbon dioxide

Molecularly imprinted polymer nanoparticles were prepared in supercritical carbon dioxide using a noncovalent imprinting approach. In the present work, propranolol was used as a model template, methacrylic acid as a functional monomer, and divinylbenzene as a crosslinker. Under a high dilution condition, the heterogeneous polymerization resulted in discrete crosslinked polymer nanoparticles. Compa