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Intracellular domains of the delta-subunits of Torpedo and rat acetylcholine receptors--expression, purification, and characterization

There are quite detailed structural data on the extracellular ligand-binding domain and the intramembrane channel-forming domain of the nicotinic acetylcholine receptors (nAChR). However, the structure of the intracellular domain, which has variable amino acid sequences in different nAChR subunits, remains unknown. We expressed in Escherichia coli the intracellular loops (between transmembrane fra

Timing and speed of migration in male, female and juvenile Ospreys Pandion haliaetus between Sweden and Africa as revealed by field observations, radar and satellite tracking

Breeding Ospreys were studied in southern Sweden and 13 birds were tracked by satellite telemetry on autumn migration to the African wintering grounds. This was supplemented with studies of migrating birds at Falsterbo and radar trackings From southern Sweden. Females generally left the nest site 2-3 weeks ahead of males and juveniles. Among males, failed bleeders migrated significantly earlier th

Spatial scale and temporal component of selection in side-blotched lizards

Spatial variation in selection has long been recognized as promoting population divergence and in maintaining genetic polymorphisms, but selection at a fine spatial scale is seldom measured directly. We analyzed spatial and temporal variation in selective regimes on egg size using long-term population data of the side-blotched lizard ( Uta stansburiana). Juvenile survival rates varied between year

Algebraic curves for commuting elements in the q-deformed Heisenberg algebra

In this paper we extend the eliminant construction of Burchnall and Chaundy for commuting differential operators in the Heisenberg algebra to the q-deformed Heisenberg algebra and show that it again provides annihilating curves for commuting elements, provided q satisfies a natural condition. As a side result we obtain estimates on the dimensions of the eigenspaces of elements of this algebra in i

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