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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

Rationalisation of the substrate concentration dependent diastereoselectivity of a Saccharomyces cerevisiae short-chain dehydrogenase

The diastereoselectivity of the carbonyl reduction of bicyclo[2.2.2]octane-2,6-dione, catalysed by the purified yeast cytosolic short-chain dehydrogenase Ymr226cp, was shown to be substrate concentration dependent. The changing selectivity was attributed to two distinct binding configurations of the substrate in the active site, each yielding a distinct hydroxy ketone diastereomer. By applying ind

Symmetry of hole spin transport in a two-terminal quantum system

We study two-terminal hole spin transport in a p-type, light-hole-heavy-hole coupled, quantum-well system under the influence of Rashba spin-orbit interaction. An expression for the spin polarization of the outgoing hole flux is derived. It is shown that the in-plane spin polarization vanishes identically whenever the outgoing lead supports only heavy-hole channels. This result is independent of t

Absorption and radiation impedance of finite absorbing patches

A variational formulation is used to calculate the sound absorption in order to incorporate the interaction between several absorbing patches of arbitrary shape. In particular, this formulation is applied to small periodic patches. The absorption characteristics are governed by the radiation impedance, Z(r), which is a function of the absorber's geometry and the incidence angle, together with the

Architecture and sedimentation of outwash fans in front of the Myrdalsjokull ice cap, Iceland

In this study, we introduce the architecture and style of sedimentation of two outwash fans in front of the Myrdalsjokull ice cap, central south Iceland, that broaden different types of ice-marginal sedimentation. At Kotlujokull, a southeastern outlet of the ice cap, fan formation was monitored from the late 1970s to 2002; thus, the style of sedimentation is well understood and the relationship to

MRI and body fluid analysis: New means to monitor early structural and metabolic changes in joint cartilage disease

Emerging knowledge of cartilage metabolism and structure has stimulated efforts to develop new cartilage-monitoring techniques in health and disease. This article gives an overview of cartilage matrix structure, cartilage metabolism, and significant exogenous factor's to show how such knowledge can guide the development of new means to monitor cartilage. Delayed contrast enhanced MRI of cartilage