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From arctic lemmings to adaptive dynamics: Charles Elton's legacy in population ecology

We shall examine the impact of Charles S. Eltons 1924 article on periodic fluctuations in animal populations on the development of modern population ecology. We argue that his impact has been substantial and that during the past 75 years of research on multi-annual periodic fluctuations in numbers of voles, lemmings, hares, lynx and game animals he has contributed much to the contemporary understa

Complement C3 and C4 in plasma and incidence of myocardial infarction and stroke: a population-based cohort study

Background Complement factor C3 and C4 have been associated with atherosclerosis and cardiovascular risk factors. This study explored whether plasma levels of C3 and C4 are risk factors for the incidence of cardiovascular disease (CVD). Design A population-based prospective study of 5850 initially healthy men, 28-61 years old at baseline. Methods Plasma levels of C3 and C4 were analysed at the bas

Two-year follow-up of Helicobacter pylori infection in C57BL/6 and Balb/cA mice.

Helicobacter pylori infection is associated with chronic gastritis, peptic ulcer disease, gastric adenocarcinoma and MALT lymphoma. We previously found high-grade lymphoma after 13 months' H. pylori infection in C57BL/6 mice. In this study we followed H. pylori infection by three different isolates in C57BL/6 and Balb/cA mice for 23 months. Six-week-old C57BL/6 and Balb/cA mice were infected with

Psychosocial work conditions, social participation and social capital: A causal pathway investigated in a longitudinal study.

Social capital is often claimed to be promoted by stable social structures such as low migration rates between neighbourhoods and social networks that remain stable over time. However, stable social structures may also inhibit the formation of social capital in the form of social networks and social participation. One example is psychosocial conditions at work, which may be determined by character

The Kullaberg peninsula – a glimpse of the Proterozoic evolution of SW Fennoscandia

The Kullaberg peninsula in NW Skåne renders km-long, continuous exposures of the Proterozoic crystalline basement. We report ion microprobe (SIMS) U–Pb zircon ages for six key lithologies at Kullaberg that constrain the geological history of SW Fennoscandia for a considerable time period. Igneous zircon in three varieties of gneiss granite yield ages of 1694±7 Ma, 1693±7 Ma and 1663±14 Ma, in the

Titanium-hydrogen peroxide interaction: model studies of the influence of the inflammatory response on titanium implants

In vitro studies of titanium and TiO2 as well as other metals were carried out to investigate the role of these metals in the inflammatory response through the Fenton reaction. The TiOOH matrix formed traps the superoxide radical, so that no or very small amounts of free hydroxyl radicals are produced. Ellipsometry and spin trapping with spectrophotometry and electron spin resonance (ESR) were use

Use of neural networks to improve quality control of interpretations in myocardial perfusion imaging

Background: The aim of this study was to explore the feasibility of using a technique based on artificial neural networks for quality assurance of image reporting. The networks were used to identify potentially suboptimal or erroneous interpretations of myocardial perfusion scintigrams (MPS). Methods: Reversible perfusion defects (ischaemia) in each of five myocardial regions, as interpreted by on

Boreal forest surface parameterization in the ECMWF model - 1D test with NOPEX long-term data

The objective of the present study was to assess the performance and recent improvements of the land surface scheme used operationally in the European Centre for Medium-Range Weather Forecasts (ECMWF) in a Scandinavian boreal forest climate/ecosystem. The previous (the 1999 scheme of P. Viterbo and A. K. Betts) and the new (Tiled ECMWF Surface Scheme for Exchange Processes over Land, TESSEL) surfa

Orientation scatter of free-flying nocturnal passerine migrants: components and causes

We investigated the variation in concentration of orientation among nocturnally migrating passerine birds. Using tracking radar, we recorded flight tracks of birds during spring and autumn migration and, with the aid of concurrent wind recordings, we calculated heading directions. The concentrations of track and heading directions were compared between seasons and also between different categories

Study of the solar wind coupling to the time difference horizontal geomagnetic field

The local ground geomagnetic field fluctuations (AB) are dominated by high frequencies and 83% of the power is located at periods of 32 min or less. By forming 10-min root-mean-square (RMS) of A B a major part of this variation is captured. Using measured geomagnetic induced currents (GIC), from a power grid transformer in Southern Sweden, it is shown that the 10-min standard deviation GIC may be

Uteroplacental and luteal circulation in normal first-trimester pregnancies: Doppler ultrasonographic and morphologic study

OBJECTIVE: Our purpose was to establish reference data representative of normal findings at transvaginal color and spectral Doppler ultrasonographic examination of the uteroplacental and luteal circulation in the first trimester and to relate the Doppler findings to morphologic data. STUDY DESIGN: A cross-sectional study was performed of 64 uncomplicated pregnancies of 5 to 11 completed gestationa

Temperament and Character Associated With Depressive Symptoms in Women: Analysis of Two Genetically Informative Samples

Although previous research has explored associations between personality and depressive symptoms, a limited number of studies have assessed the extent to which genetic and environmental influences explain the association. This study investigated how temperament and character were associated with depressive symptoms in 131 pairs of twin and sibling women in early adulthood, as well as 326 pairs of

Homogenization of woven materials

The effective electric and magnetic material properties of a complex (two-component) mixture are addressed. The mixture is periodic in two directions and has a finite thickness in the third direction. Specifically, the explicit problem of finding the effective electric parameters for slab that has been reinforced by a layer (or several layers) of glass fiber is investigated. The homogenization pro

Upper airway obstruction in patients with rheumatoid arthritis and temporomandibular joint destruction

Among 400 patients with rheumatoid arthritis and measurable ramus height there were 76 patients with mutilating arthritis of the temporomandibular joints. In 30 of these 400 patients, episodes of upper airway obstruction had occurred, mostly when the patient lay supine. Laryngoscopy had been performed in only 7 patients, and in 3 of those a laryngeal arthritis was detected. Upper airway obstructio