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Orientation of nocturnally migrating Swainson's thrush at dawn and dusk: Importance of energetic condition and geomagnetic cues

We studied the early morning cage orientation of nocturnally migrating Swainson's Thrushes (Catharus ustulatus) during three fall migration seasons. The results were compared with earlier free-flight release tests under starry skies and were found to be consistent with continuation of migratory flights in the expected seasonally appropriate direction. Energetic condition proved decisive: fat birds

Deuteron and triton production with high energy sulphur and lead beams

Proton and deuteron production has been observed in S+S and S+Pb collisions at 200 A-GeV and in Pb+Pb reactions at 158 A-GeV at the CERN SPS accelerator. For Pb+Pb triton production was also measured. The p and d spectra as well as the p and t spectra were observed in similar rapidity ranges and over similar ranges of transverse momenta per nucleon, making it possible to interpret the cross sectio

Role of striatal l-DOPA in the production of dyskinesia in 6-hydroxydopamine lesioned rats.

We explored possible differences in the peripheral and central pharmacokinetics of L-DOPA as a basis for individual variation in the liability to dyskinesia. Unilaterally, 6-hydroxydopamine (6-OHDA) lesioned rats were treated chronically with L-DOPA for an induction and monitoring of abnormal involuntary movements (AIMs). Comparisons between dyskinetic and non-dyskinetic cases were then carried ou

A combination of magnetic permeability detection with nanometer-scaled superparamagnetic tracer and its application for one-step detection of human urinary albumin in undiluted urine

A rapid (6.5 min) and simple one-step magnetic immunoassay (MIA) has been developed for analysis of human urinary albumin in near patient settings. Polyclonal rabbit anti-human albumin was used as a capture antibody and monoclonal mouse anti-human albumin as a detection antibody in a two-site immunometric assay requiring no additional washing procedures. The polyclonal anti-human albumin was conju

Growth and development of larval Rana temporaria: Local variation and countergradient selection

I raised tadpoles of the Common Frog (Rana temporaria) from populations in eight source ponds in southern Sweden, in a common garden experiment at two densities. Tadpoles from different populations differed in development rate; those from source ponds with high tadpole densities developed faster than those from less crowded ponds. Thus, differences among ponds in tadpole performance, which were do

Electrochemical studies on antioxidants in bovine milk

Cyclic voltammetry (CV), rotating disk electrode (RDE) linear sweep voltammetry and flow-injection amperometry (FIAmp) were used to investigate the possibility to determine antioxidants in bovine milk, whey and low-molecular-weight (LMW) fractions of whey. Using CV one major current wave was found in all types of samples at oxidation potentials between +600 and +700 mV against Ag | AgCl|0.1 mol l−

Performance Limits in Adaptive Control

Minimum variance control of difference equations systems with time-varying stochastic parameters are studied. The optimal control law is derived under the assumption that all previous, but not the current parameter values are known. This is used to give performance limits for dual control. In particular, it is shown that too much parameter uncertainty may cause the system to be unstable in the sen

The impact of the electrical potential gradient on limestone dissolution under wet flue gas desulfurization conditions

The flux of an ion in an ionic solution is due to a concentration gradient and an electrical potential gradient. The latter is a result of differences in the diffusion constants of the diffusing ions. Even though it is possible to express the electrical potential gradient in terms of concentrations and concentration gradients, it results in a complicated system to solve if more than two species di

Habitat-specific pigmentation in a freshwater isopod: Adaptive evolution over a small spatiotemporal scale

Pigmentation in the freshwater isopod Asellus aquaticus (Crustacea) differed between habitats in two Swedish lakes. In both lakes, isopods had lighter pigmentation in stands of submerged vegetation, consisting of stoneworts (Chara spp.), than in nearby stands of reed (Phragmites australis). Experimental crossings of light and dark isopods in a common environment showed that pigmentation had a gene

Glucose-sensing mechanisms in pancreatic beta-cells

The appropriate secretion of insulin from pancreatic beta-cells is critically important to the maintenance of energy homeostasis. The beta-cells must sense and respond suitably to postprandial increases of blood glucose, and perturbation of glucose-sensing in these cells can lead to hypoglycaemia or hyperglycaemias and ultimately diabetes. Here, we review beta-cell glucose-sensing with a particula

Expression pattern analysis of transcribed HERV sequences is complicated by ex vivo recombination

Background: The human genome comprises numerous human endogenous retroviruses ( HERVs) that formed millions of years ago in ancestral species. A number of loci of the HERV-K(HML-2) family are evolutionarily much younger. A recent study suggested an infectious HERV-K(HML-2) variant in humans and other primates. Isolating such a varian t from human individuals would be a significant finding for huma