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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

A prospective pilot study of antibodies against human papillomaviruses and cutaneous squamous cell carcinoma nested in the Oxford component of the European Prospective Investigation into Cancer and Nutrition

In a prospective pilot study nested in the EPIC-Oxford cohort, we examined the seroprevalence of antibodies against the L1 antigen of 38 human papilloma virus (HPV) types among 39 cases of cutaneous squamous cell carcinoma (SCC) for whom plasma was collected prior to diagnosis (incident) and 80 controls. Fifteen cases having already developed SCC at blood collection (prevalent) were also tested. T

Telomere-mediated mitotic disturbances in immortalized ovarian epithelial cells reproduce chromosomal losses and breakpoints from ovarian carcinoma

Ovarian carcinomas (OCs) often exhibit highly complex cytogenetic changes. Abnormal chromosome segregation at mitosis is one potential mechanism for genomic rearrangements in tumors. In this study, OCs were demonstrated to have dysfunctional short telomeres, anaphase bridging, and multipolar mitoses with supernumerary centrosomes. When normal human ovarian surface epithelial (HOSE) cells were tran

Two new molecular bases for the Dombrock null phenotype

Red blood cells (RBCs) with the Do(null) phenotype lack all antigens in the Dombrock blood group system, i.e. Do(a), Do(b), Gy(a), Hy and Jo(a). Sequence analysis of DNA from one proband with the Do(null) phenotype revealed a single nucleotide mutation of t to c in the donor splice site of DO (IVS1 + 2t > c), with outsplicing of exon 2. Analysis of a second proband revealed a homozygous nonsense m

Chromosomal aberrations and risk of cancer in humans: an epidemiologic perspective

The pioneering papers published more than one century ago by Theodor Boveri opened the way to extensive research on the mechanism linking chromosomal abnormalities to the pathogenesis of cancer. As a result of this effort, robust theoretical and empirical evidence correlating cytogenetic damage to early stages of cancer in humans was consolidated, and an increased cancer risk was postulated in hea

Chaos in the Nucleus: SD Decay-out and Masses

Some consequences of chaos in the nucleus are discussed. The decay-out from superdeformed band occurs in a region where normal-deformed states may be chaotic, and it is shown how the distribution of decay-out matrix elements may reveal the degree of chaos. The decay-out is mediated by doorway states that are not resolved in the A=190 region, but experimentally seen in 59Cu. A model for the decay-o

The white-backed woodpecker: umbrella species for forest conservation planning?

n northern Europe, a long history of land use has led to profound changes within forest ecosystems. The white-backed woodpecker (Dendrocopos leucotos) is one of several specialised forest species whose populations have declined. Conservation management directed at this species’ habitat has made it a de facto umbrella species for conservation of the biodiversity associated with forests rich in deci

Volatile organic compound emissions when drying wood particles at high dewpoints

Emission of volatile org. compds. (VOCs) during drying of wood particles for particleboard manuf., or for prodn. of refined biofuels, is a potential environmental problem. The aim of this work is to study the emissions of VOCs during drying, and the influence on the emissions by different drying parameters. The expts. have mainly been done in a batch fluidized bed dryer, but measurements have also

Cib2 binds integrin a7Bb1D and is reduced in laminin a2 chain deficient muscular dystrophy

Mutations in the gene encoding laminin alpha 2 chain cause congenital muscular dystrophy type 1A. In skeletal muscle, laminin alpha 2 chain binds at least two receptor complexes: the dystrophin-glycoprotein complex and integrin alpha 7 beta 1. To gain insight into the molecular mechanisms underlying this disorder, we performed gene expression profiling of laminin alpha 2 chain-deficient mouse limb

Serum levels of autoantibodies against monomeric C-reactive protein are correlated with disease activity in systemic lupus erythematosus

This study was performed to investigate the relation between IgG autoantibodies against human C-reactive protein (antiCRP) and disease activity measures in serial serum samples from 10 patients with systemic lupus erythematosus (SLE), of whom four had active kidney involvement during the study period. The presence of anti-CRP was analysed by enzyme-linked immunosorbent assay. The cut-off for posit

Risk factors for extrahepatic biliary tract carcinoma in men: medical conditions and lifestyle: results from a European multicentre case-control study

OBJECTIVES: To identify risk factors of carcinoma of the extrahepatic biliary tract in men. METHODS: Newly diagnosed and histologically confirmed patients, 35-70 years old, were interviewed between 1995 and 1997 in Denmark, Sweden, France, Germany and Italy. Population controls were frequency-matched by age and region. Adjusted odds ratios and 95%-confidence intervals were estimated by logistic re

Genetic diversity and phenotypic variation in marginal populations of the locally endangered species Hordeum secanlinum (Poaceae).

Electrophoresis was used to compare variation in hordein polypeptide patterns and isozymes in five marginal populations ofHordeum secalinum (four Swedish and one Danish population) and four populations along the Atlantic coast from Denmark to Spain. Hordein patterns were uniform within and among Swedish and Danish populations whereas the materials from France and Spain were divergent. The banding

A comparison of two feedforward control structure assessment methods

The most common loop in an industrial plant is a SISO-loop with a PI(D)controller. If the loop is affected by disturbances,these can be handled by adding a feedforward control action. In an industrial control system there are many measured signals, apart from those of the loop, available. The question we address in this article is how to select the feedforward variable out of the available measure

Effects of enrichment on simple aquatic food webs

Simple models, based on Lotka-Volterra types of interactions between predator and prey, predict that enrichment will have a destabilizing effect on populations and that equilibrium population densities will change at the top trophic level and every second level below. We experimentally tested these predictions in three aquatic food web configurations subjected to either high or low nutrient additi

Bioavailability and sources of DOC and DON in macrophyte stands of a tropical coastal lake

Dissolved organic carbon (DOC) and nitrogen (DON) derived from aquatic and terrestrial vascular plants provide a major energy and nutrient source for freshwater and coastal marine biota. The bioavailability of this material may to a large extent depend on plant species. In this study, we have compared the bioavailability of DOC and DON sampled in two distinct stands of Typha domingensis and Eleoch