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Central processing of plant volatiles in Agrotis ipsilon males is age-independent in contrast to sex pheromone processing.

Male moths rely on female sex pheromones to find their mating partner and on plant volatiles for the detection of food sources. In the noctuid moth, Agrotis ipsilon, plasticity of central sex pheromone processing has been shown previously in the antennal lobe. The sensitivity of antennal lobe interneurons increases with age and juvenile hormone level. Here we investigated whether age affects not o

Zener tunneling between Wannier-Stark levels in GaAs/AlGaAs superlattices

We have performed a detailed calculation of the inter-Wannier-Stark-ladder Zener tunneling probability P(F) in a wide-miniband GaAs/Al0.3Ga0.7As superlattice under a strong electric field F, the terahertz emission spectrum I(F) of which was measured experimentally. By comparing P(F) and I(F), we confirm that the oscillating behavior of I(F) is due to the Zener tunneling between Wannier-Stark level

Room-temperature semiconductor heterostructure refrigeration

With the proper design of semiconductor tunneling barrier structures, we can inject low-energy electrons via resonant tunneling, and take out high-energy electrons via a thermionic process. This is the operation principle of our semiconductor heterostructure refrigerator (SHR) without the need of applying a temperature gradient across the device. Even for the bad thermoelectric material AlGaAs, ou

Free testosterone is an independent predictor of BMD and prevalent fractures in elderly men: MrOS Sweden

The role of androgens for bone health in elderly men is unclear. We show that free testosterone within the normal range is a predictor of BMD at predominantly cortical bone sites and of previous osteoporosis-related fractures in elderly Swedish men. Introduction: Osteoporosis-related fractures constitute a major health concern not only in women but also in men. Previous studies have clearly shown

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(