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Sexual selection drives asymmetric introgression in wall lizards.

Hybridisation is increasingly recognised as an important cause of diversification and adaptation. Here, we show how divergence in male secondary sexual characters between two lineages of the common wall lizard (Podarcis muralis) gives rise to strong asymmetries in male competitive ability and mating success, resulting in asymmetric hybridisation upon secondary contact. Combined with no negative ef

Coupling of methyl and total mercury in a minerotrophic peat bog in southeastern Sweden

During most of an annual cycle, we studied the temporal variation of total mercury (Hg-T) and methyl mercury (MeHg) in unfiltered and filtered (0.45 mu) peat water from a minerotrophic peat bog in southeastern Sweden. MeHg in bulk water ([MeHgT]) and total Hg in filtered water in discharge water from the peat bog ([Hg-D]) were an order of magnitude higher than in upland runoff water entering the p

Electrocardiographic characteristics of fibrillatory waves in new-onset atrial fibrillation

Aims In atrial. fibrillation (AF), fibrillatory waves of surface electrocardiograms (ECG) vary among patients with respect to waveform and repetition rate. The purpose of this study was to (i) explore clinical determinants of new-onset AF and (ii) determine prognostic significance to predict initial treatment outcome of electrocardiographic fibrillatory wave characteristics in new-onset AF Methods

The effect of dominance on food hoarding: A game theoretical model

Many food hoarding animals live in small groups structured by rank. The presence of conspecifics in the hoarding area increases the risk of losing stored supplies. The possibility of stealing from others depends on a forager's rank in the group. Highly ranked individuals can steal from subordinates and also protect their own caches. Since storing incurs both costs and benefits, the optimal hoardin

Percutaneous transvenous mitral annuloplasty (PTMA) with the Viking device reduces pacing-induced mitral regurgitation.

Objectives: The new percutaneous mitral annuloplasty Viking device was evaluated in surviving sheep with pacing-induced mitral regurgitation. Methods and results: Twenty sheep were subjected to rapid ventricular pacing for one to three months, leading to cardiomyopathy and mitral regurgitation. Device implantation could be successfully performed in 11 of these animals after pacemaker treatment for

The P446L variant in GCKR associated with fasting plasma glucose and triglyceride levels exerts its effect through increased glucokinase activity in liver

Genome-wide association studies have identified a number of signals for both Type 2 Diabetes and related quantitative traits. For the majority of loci, the transition from association signal to mutational mechanism has been difficult to establish. Glucokinase (GCK) regulates glucose storage and disposal in the liver where its activity is regulated by glucokinase regulatory protein (GKRP; gene name

Prospective Safety Surveillance of GH-Deficient Adults: Comparison of GH-Treated vs Untreated Patients.

Context:In clinical practice, the safety profile of GH replacement therapy for GH-deficient adults compared with no replacement therapy is unknown.Objective:The objective of this study was to compare adverse events (AEs) in GH-deficient adults who were GH-treated with those in GH-deficient adults who did not receive GH replacement.Design and Setting:This was a prospective observational study in th

John Birks: Pioneer in quantitative palaeoecology

We describe the career of John Birks as a pioneering scientist who has, over a career spanning five decades, transformed palaeoecology from a largely descriptive to a rigorous quantitative science relevant to contemporary questions in ecology and environmental change. We review his influence on students and colleagues not only at Cambridge and Bergen Universities, his places of primary employment,

The efficiency potential of ICT in haulier operations

What is the efficiency potential of Information Communication Technology (ICT) in haulier operations? Previous literature has focused on the aggregated level benefits that could be achieved once a large proportion of hauliers have introduced ICT in their trucks. In reality, hauliers are only ready to invest in technologies that generate business benefits, yet there is a gap in the literature regar

An observational study of outcome in SLE patients with biopsy-verified glomerulonephritis between 1986 and 2004 in a defined area of Southern Sweden: the clinical utility of the ACR renal response criteria and predictors for renal outcome.

Objectives: To test the utility of the World Health Organization (WHO) and International Society of Nephrology/Renal Pathology Society (ISN/RPS) criteria for lupus nephritis (LN) in systemic lupus erythematosus (SLE) and the American College of Rheumatology renal response criteria (ACR-RRC) for renal follow-up in an observational cohort. Method: All 52 biopsy-verified cases of LN during 19 years w

Selective infection of E. coli as a function of a specific molecular interaction.

Selective infection of phage is when the bacterial infection depends on the specific molecular interaction between an antigen and a phage-displayed protein sequence such as an antibody. Engineering of the normal infection into pathways, directed by a specific protein--protein interaction, has raised several mechanistic questions. Here, we address the type of display and the affinity between the in

Polarized subsets of human T-helper cells induce distinct patterns of chemokine production by normal and systemic sclerosis dermal fibroblasts

The role of fibroblasts in inflammatory processes and their cross-talk with T cells is increasingly being recognized. Our aim was to explore the capacity of dermal fibroblasts to produce inflammatory chemokines potentially involved in fibrosis occurring in response to contact with polarized human T cells. Our findings indicate that the program of chemokine production by fibroblasts is differential

Flare-up reactions after oral challenge with nickel in relation to challenge dose and intensity and time of previous patch test reactions

BACKGROUND: In this study we have taken an interest in systemic exposure to nickel in patients with delayed hypersensitivity to nickel. OBJECTIVE: The aim of the study was to more closely investigate the importance of factors such as ingested nickel dose, time interval between nickel patch testing and oral nickel challenge as well as degree of nickel hypersensitivity in relation to flare-up reacti

Background factors influencing somatic and psychological symptoms in middle-age women with different hormonal status A population-based study of Swedish women.

Objective: To analyse the influence of socio-demographic characteristics and environmental factors on self-reported somatic and psychological symptoms among middle-aged Swedish women. Methods: A total of 6917 women living in the Lund area of southern Sweden were participates of this study. They completed a generic questionnaire pertaining to socio-demographic characteristics, lifestyle factors and

Approximating longest directed paths and cycles

We investigate the hardness of approximating the longest path and the longest cycle in directed graphs on n vertices. We show that neither of these two problems can be polynomial time approximated within n(1-epsilon)for any epsilon > 0 unless P = NP. In particular, the result holds for digraphs of constant bounded outdegree that contain a Hamiltonian cycle. Assuming the stronger complexity conject

Long-term testosterone stimulation induces hyperplasia in the guinea-pig prostate.

The relation between supraphysiologic circulating testosterone levels and prostatic diseases is unclear and difficult to study in men. Animal models may be advantageous. Based on a pilot study, testosterone enantate 50 mg (n=12) or 25 mg (n=12) was administered to guinea-pigs intramuscularly every 3 weeks, for either 7 or 14 months. The histopathology of the prostate was described. Epithelial hype

Prior information in fluorescence molecular tomography based on multispectral fluorescence emission

Fluorescence molecular tomography (FMT) suffers from inherent ill-posedness due to the vast number of possible solutions to the reconstruction problem. To increase the robustness of such a problem one need prior information. We present here a method for rendering a priori information of the position of a fluorescent inclusion inside turbid media. The method utilizes solely two spectral bands withi

Absolute quantification of cerebral blood flow in normal volunteers: Correlation between Xe-133SPECT and dynamic susceptibility contrast MRI

Purpose: To compare, absolute cerebral blood flow (CBF) estimates obtained by dynamic susceptibility contrast MRI (DSC-MRI) and Xe-133 SPECT. Materials and Methods: CBF was measured in 20 healthy volunteers using DSC-MRI at 3T and Xe-133 SPECT. DSC- MRI was accomplished by gradient-echo EPI and CBF was calculated using a time-shift-insenisitive deconvolution algorithm and regional arterial input f