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In running waters, chemical cues have generally been assumed to always come from upstream locations. Here, we present ¢eld and laboratory evidence that Gammarus pulex can use chemical cues from down- stream predators to adaptively adjust drifting behaviour. In the ¢eld, signi¢cantly fewer Gammarus migrated into stream enclosures where brown trout (Salmo trutta) were present than into control enclo

The development of a mathematical model and a computer program to facilitate the study of the multi-cylinder paper drying process is presented. Experimentally determined values far different heat and mass transfer coefficients are used to ensure the physical validity of the model. A unique feature of the model is its inclusion of a mass transfer coefficient for the dryer fabric. Thus far, the mass

Lithium tetrahydridoboranate (LiBH4) may be a potentially interesting material for hydrogen storage, but in order to absorb and desorb hydrogen routinely and reversibly, the kinetics and thermodynamics need to be improved significantly. A priori, this material has one of the highest theoretical gravimetric hydrogen contents, 18.5 wt%, but unfortunately for practical applications, hydrogen release

Aim The intention with this study was first to investigate and describe the broad-scale geographical patterns of species richness of breeding shorebirds (Charadriiformes; families: Charadriidae, Scolopacidae and Haematopodidae) throughout the arctic tundra biome. Secondly, after compensating for the positive relationship between net primary productivity (NPP) and species richness, the relative imp

Nine young, healthy male volunteers were given ethanol (75 g/day) for 5 weeks. The ethanol was divided into five daily doses and taken so that blood ethanol levels never exceeded 0.04% (w/v). During the latter part of the ethanol intake period, there was a significant, transient increase of plasma triglyceride (TG) concentrations followed by reduction to normal levels. A three-fold increase of lip

TBX22 belongs to the T-box family of transcription factors and was originally found in an in silico approach designed to identify new genes on the human Xq12-q21 region. Mutations in TBX22 have been reported in families with X-linked cleft palate and ankyloglossia (CPX), but the underlying pathogenetic mechanism remained unknown. We have identified mouse Tbx22 and analyzed its expression during em

According to antibody analysis, approximately two of every three intravenous drug users in Iceland have become infected with hepatitis C virus (HCV). In this study, serum samples from 55 HCV antibody-positive intravenous drug users (39 males and 16 females) were analyzed by polymerase chain reaction, and the viral strains were grouped into genotypes. Only three genotypes--1a, 3a, and 1b--were foun

The present series comprises all families (n = 77) with haemophilia B in Sweden and may be considered to be representative for the purposes of a population-based study of mutational heterogeneity. The 77 families (38 severe, 10 moderate, 29 mild) had 51 different mutations in total. Thirteen families had total, partial or small deletions, two had mutations in the promoter, eight families had splic

The sequence of peaks and troughs in a load process acting on a material, contains important information about the damage caused by the load, e.g. on the growth rate of a widening crack. The stress range, i.e. the difference between a peak and the following trough, is one of the variables that is used to describe e.g. fatigue life under random loading. The moments, in particular the mean and varia

Factors affecting phase separation in water-salt solutions of polyelectrolyte complexes (PECs), formed by DNA and integral or pendant polycations with a quaternary amino group in every monomer unit, have been studied. When no salt was added, quantitative DNA precipitation occurred at a stoichiometric charge ratio, = [+]/[-] 1. In DNA mixtures with poly(N,N'-dimethyldiallylammonium chloride) (PDMDA

Multiple and variable tyrosine sulfation in extracellular class II leucine-rich repeat proteins/proteoglycans were characterized by mass spectrometry. The sulfogroup on tyrosine is labile and is released from peptides under normal mass spectrometric conditions. Thus, special approaches must be considered in order to identify this modification. By using a combination of mass spectrometry studies op

The extension theory for semibounded symmetric operators is generalized by including operators acting in a triplet of Hilbert spaces. We concentrate our attention on the case where the minimal operator is essentially self-adjoint in the basic Hilbert space and construct a family of its self-adjoint extensions inside the triplet. All such extensions can be described by certain boundary conditions,

Many lines of evidence implicate mitochondria in phenotypic variation: ( a) rare mutations in mitochondrial proteins cause metabolic, neurological, and muscular disorders; ( b) alterations in oxidative phosphorylation are characteristic of type 2 diabetes, Parkinson disease, Huntington disease, and other diseases; and ( c) common missense variants in the mitochondrial genome ( mtDNA) have been imp

A system based on a femtosecond white-light continuum and a streak camera was used for recordings of the in vivo absorption spectra of the tumor-seeking agent disulphonated aluminum phthalocyanine. Measurements for different drug doses were performed on tumor tissue (muscle-implanted adenocarcinoma) and normal muscle tissue in rats. It was found that the shape of the spectrum is tissue dependent.

SJL mice colonized with RcsX lymphoma cells undergo a rapid inflammatory response associated with biological and physiological effects including increased nitric oxide production and mutations in spleen DNA. By 2 weeks postcolonization, these changes were accompanied by both up- and down-regulation of a number of plasma proteins. In the experiments reported here, plasma from individual SJL mice wa

Polymorphisms in genes that encode for metabolic enzymes have been associated with variations in enzyme activity between individuals. Such variations could be associated with differences in individual exposure to carcinogens that are metabolized by these genes. In this study, we examine the association between polymorphisms in several metabolic genes and the consumption of tobacco in a large sampl