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Number of spikes in climbing fibers determines the direction of cerebellar learning.

Cerebellar learning requires context information from mossy fibers and a teaching signal through the climbing fibers from the inferior olive. Although the inferior olive fires in bursts, virtually all studies have used a teaching signal consisting of a single pulse. Following a number of failed attempts to induce cerebellar learning in decerebrate ferrets with a nonburst signal, we tested the effe

To fly or not to fly depending on winds: shorebird migration in different seasonal wind regimes

Migratory birds are predicted to adapt their departure to wind, changing their threshold of departure and selectivity of the most favourable winds in relation to the mean, scatter and skewness of the wind regime. The optimal departure behaviour depends also on the importance of time and energy minimization during migration and on the ratio of cost of flight to cost of resting and waiting for more

Potentiometric propranolol-selective sensor based on molecularly imprinted polymer

A novel potentiometric sensor based on molecularly imprinted polymer (MIP) for propranolol, an adrenergic-blocking drug, was designed. The influence of molecularly imprinted polymer particle content and sodium tetraphenylborate additives in polyvinylchloride membrane was shown. The electrodes show near-Nernstian responses down to 10(-4)-10(-5) M propranolol concentration. The potentiometric respon

Hypoxia Sustains Cyanobacteria Blooms in the Baltic Sea

Nutrient over-enrichment is one of the classic triggering mechanisms for the occurrence of cyanobacteria blooms in aquatic ecosystems. In the Baltic Sea, cyanobacteria regularly occur in the late summer months and form nuisance accumulations in surface waters and their abundance has intensified significantly in the past 50 years attributed to human-induced eutrophication. However, the natural occu

Chronic glucokinase activation reduces glycaemia and improves glucose tolerance in high-fat diet fed mice.

Glucokinase (GK) plays a key role in maintaining glucose homeostasis by promoting insulin secretion from pancreatic beta cells and increasing hepatic glucose uptake. Here we investigate the effects of acute and chronic GK activation on glucose tolerance and insulin secretion in mice with diet-induced insulin resistance. In the acute study, a small molecule GK activator (GKA71) was administered to

Intake levels of dietary long-chain PUFAs modify the association between genetic variation in FADS and LDL-C

Polymorphisms of the FA desaturase (FADS) gene cluster have been associated with LDL, HDL, and triglyceride concentrations. Because FADS converts alpha-linolenic acid (ALA) and linoleic acid into PUFAs, we investigated the interaction between different PUFA intakes and the FADS polymorphism rs174547 (T>C) on fasting blood lipid and lipoprotein concentrations. We included 4,635 individuals (60% fem

Water-Insoluble Surface Coatings of Polyion−Surfactant Ion Complex Salts Respond to Additives in a Surrounding Aqueous Solution

Hydrated, but water-insoluble, “complex salts” (CS) composed of alkyltrimethylammonium surfactant ions with polyacrylate counterions are known to exhibit a rich phase behavior in bulk mixtures with water and have recently been shown to act as water-responsive surface coatings. Here it is shown, by SAXS measurements, that surface coatings of CS also respond to various added solutes in a surrounding

Bird colour vision: behavioural thresholds reveal receptor noise.

Birds have impressive physiological adaptations for colour vision, including tetrachromacy and coloured oil droplets, yet it is not clear exactly how well birds can discriminate the reflecting object colours that they encounter in nature. With behavioural experiments, we determined colour discrimination thresholds of chickens in bright and dim light. We performed the experiments with two colour se

The impact of low-frequency and rare variants on lipid levels.

Using a genome-wide screen of 9.6 million genetic variants achieved through 1000 Genomes Project imputation in 62,166 samples, we identify association to lipid traits in 93 loci, including 79 previously identified loci with new lead SNPs and 10 new loci, 15 loci with a low-frequency lead SNP and 10 loci with a missense lead SNP, and 2 loci with an accumulation of rare variants. In six loci, SNPs w

Peptidyl arginine deiminase from Porphyromonas gingivalis abolishes C5a activity.

Evasion of killing by the complement system, a crucial part of innate immunity, is a key evolutionary strategy of many human pathogens. A major etiological agent of chronic periodontitis, the Gram-negative bacterium Porphyromonas gingivalis produces a vast arsenal of virulence factors that compromise human defense mechanisms. One of these is peptidylarginine deiminase (PPAD), an enzyme unique to P

Intervening in youth problem behavior in Sweden: a pragmatic cost analysis of MST from a randomized trial with conduct disordered youth

Int J Soc Welfare 2010: 19: 194-205 (C) 2009 The Author(s), Journal compilation (C) 2009 Blackwell Publishing Ltd and the International Journal of Social Welfare. Within the context of a randomized trial, this study assessed the costs of treating conduct disorder with multisystemic therapy (MST) or treatment as usual (TAU) for 156 youth in Sweden. From the perspective of the municipal Social Welfa

Serum estradiol does not differentiate stress, mixed and urge incontinent women around menopause. A report from the Women's Health in the Lund Area (WHILA) study.

OBJECTIVE: To outline serum estradiol levels in perimenopausal women with stress, mixed or urge incontinence. We believe the majority of urgency symptoms in perimenopausal women to be caused by a pelvic floor dysfunction and a hypermobility of the bladder neck. If this is the case, there would be no difference in estradiol levels between the groups. STUDY DESIGN: Setting: University hospital. In t

Endoscopic retrograde cholangiopancreatography with rendezvous cannulation reduces pancreatic injury

AIM: To examine whether rendezvous endoscopic retrograde cholangiopancreatography (ERCP) is associated with less pancreatic damage, measured as leakage of proenzymes, than conventional ERCP. METHODS: Patients (n = 122) with symptomatic gallstone disease, intact papilla and no ongoing inflammation, were prospectively enrolled in this case-control designed study. Eighty-one patients were subjected t

Crucial role of alkaline sphingomyelinase in sphingomyelin digestion: A study on the enzyme knockout mice.

Alkaline sphingomyelinase (alk-SMase) hydrolyses sphingomyelin (SM) to ceramide in the gut. To evaluate physiological importance of the enzyme, we generated alk-SMase knockout (KO) mice by Cre-LoxP system and studied SM digestion. Both wild type (WT) and the KO mice were fed 3H-palmitic acid labeled SM together with milk SM by gavage. The lipids in intestinal content, intestinal tissues, serum and

Airborne microalgae : Insights, opportunities, and challenges

Airborne dispersal of microalgae has largely been a blind spot in environmental biological studies because of their low concentration in the atmosphere and the technical limitations in investigating microalgae from air samples. Recent studies show that airborne microalgae can survive air transportation and interact with the environment, possibly influencing their deposition rates. This minireview

Genetic predisposition to weight loss & regain with lifestyle intervention: analyses from the Diabetes Prevention Program & the Look AHEAD randomized controlled trials.

Clinically relevant weight loss is achievable through lifestyle modification, but unintentional weight regain is common. We investigated whether recently discovered genetic variants affect weight loss and/or weight regain during behavioral intervention. Participants at high-risk of (Diabetes Prevention Program [DPP]; N=917/907 intervention/comparison) or with (Look AHEAD; N=2,014/1,892 interventio

Effect of Common Genetic Variants Associated with Type 2 Diabetes and Glycemic Traits on α- and β-cell Function and Insulin Action in Man.

Although meta-analyses of genome-wide association studies have identified more than 60 single nucleotide polymorphisms (SNPs) associated with type 2 diabetes and/or glycemic traits, there is little information whether these variants also affect α-cell function. The aim of the present study was to evaluate the effects of glycemia-associated genetic loci on islet function in vivo and in vitro. We st

Detecting and Counting Small Pattern Graphs

We study the induced subgraph isomorphism problem and the general subgraph isomorphism problem for small pattern graphs. We present a new general method for detecting induced subgraphs of a host graph isomorphic to a fixed pattern graph by reduction to polynomial testing for non-identity with zero over a field of finite characteristic. It yields new upper time bounds for several pattern graphs on

A comparison between Markov approximations and other methods for large spatial data sets

The Matern covariance function is a popular choice for modeling dependence in spatial environmental data. Standard Matern covariance models are, however, often computationally infeasible for large data sets. Recent results for Markov approximations of Gaussian Matern fields based on Hilbert space approximations are extended using wavelet basis functions. Using a simulation-based study, these Marko