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Studies in the Melica ciliata-complex: 1. Distribution of allozyme variation within and among individuals, populations and geographic regions

Allozyme variation in 83 European populations of the Melica ciliata/transsilvanica species complex has been investigated. In spite of a diploid chromosome number, most loci were duplicated and patterns of within-population variation were not explainable unless apomixis or uncommon patterns of chromosomal segregation were assumed. Allelic richness and genetic diversity were very high but most of th

Resonances and irreversibility for Schroedinger evolution

The relations between the Schrödinger and wave evolutions are investigated. A generalization of the Lax-Phillips scattering theory for the case of the Schrödinger equation is constructed. An analog of the wave decay operator is obtained. The general ideas are illustrated by an explicitly solvable model of multichannel scattering on the halfaxis. A Lax-Phillips scattering theory is developed for th

Detection and identification of protein isoforms using cluster analysis of MALDI-MS mass spectra

We describe an approach to screen large sets of MALDI-MS mass spectra for protein isoforms separated on two-dimensional electrophoresis gels. Mass spectra are matched against each other by utilizing extracted peak mass lists and hierarchical clustering. The output is presented as dendrograms in which protein isoforms cluster together. Clustering could be applied to mass spectra from different samp

The influence of external nitrogen on carbon allocation to Glomus intraradices in monoxenic arbuscular mycorrhiza

The influence of external nitrogen (N) on carbon (C) allocation and processes related to phosphorus (P) metabolism were studied in monoxenic arbuscular mycorrhiza (AM) cultures of Daucus carota. Fungal hyphae of Glomus intraradices proliferated from colonized roots growing on solid medium into C-free liquid minimal medium with two different N and P levels. Furthermore, we exposed the colonized roo

Combined flow cytometry and confocal laser scanning microscopy for evaluation of BR96 antibody cancer cell targeting and internalization.

Background: Monoclonal antibodies (mAb) are important tools in the management of tumor disease, and the discovery of antibodies with both specific cancer cell targeting and capacity to enter the cells by internalization are critical to improve the therapeutic efficacy. Method: Antibody cancer cell targeting and internalization properties of fluoroscein-conjugated mAb made against Lewis Y (BR96) we

Metapopulation pollination in the deceptive orchid Anacamptis pyramidalis

Pollen dispersal between local plant populations within a range of 6 kin in a geographically defined metapopulation of the lepidopteran-pollinated deceptive orchid Anacamptis pyramidalis was studied on the island Oland in the Baltic Sea. Local A. pyramidalis populations were examined for pollinators, flowering individuals, and fruit set. Population sizes of pollen vector species were estimated usi

Osteoclast-derived serum tartrate-resistant acid phosphatase 5b in Albers-Schonberg disease (type II autosomal dominant osteopetrosis)

BACKGROUND: Albers-Schonberg disease, or autosomal dominant osteopetrosis type II (ADO2), is caused by ineffective osteoclastic bone resorption resulting from mutations in the chloride channel 7 (ClCN7) gene. Individuals with ADO2 have increased numbers of large ineffective osteoclasts in addition to increased serum total tartrate-resistant acid phosphatase (TRACP) activity. METHODS: We investigat

Temporin A and its retro-analogues: synthesis, conformational analysis and antimicrobial activities

Temporin A (TA) is a hydrophobic peptide isolated from the skin of the European red frog Rana temporaria. Strong antimicrobial activity against gram-positive cocci and Candida, as well as its small molecular weight (10-13 aa residues), makes TA an interesting antimicrobial compound. However, its synthesis is rather problematic. Here, the synthesis of two retro-analogues of TA--retro-TA and (6-1)(7

Time-domain direct and inverse scattering for bi-anisotropic slabs at oblique incidence

Using the Cayley–Hamilton theorem and unique solubility of scalar Volterra convolution equations of the second kind, the inverse problem of determining the four time-dependent susceptibility dyadics of a linear, homogeneous, bi-anisotropic slab from generic scattering data at oblique incidence is shown to be well posed. An explicit formula for the crucial step is given.

Computer analysis of three-dimensional power angiography images of foetal cerebral, lung and placental circulation in normal and high-risk pregnancy

Three-dimensional (3-D) ultrasound (US) has greatly improved evaluation of organ circulation. The aim of this study was to explore the possible use of this new technique in normal and high-risk pregnancies. Fetal brain, lung and placenta 3-D power Doppler signal intensity were recorded in 115 normal singleton pregnancies (24 to 42 weeks gestation) and in 67 high-risk pregnancies. Mean image pixel

Barriers to energy crops in Poland from the farmers perspective

With the recent expansions of the European Union, there are now 12 new member states that are implementing European policy. One of these policies, with implications for energy production and security, is the Common Agricultural Policy. This article will focus on the impact the Common Agricultural Policy can have on farmers in Poland who have been encouraged by calls to cultivate energy crops. In a

Would prostate cancer detected by screening with prostate-specific antigen develop into clinical cancer if left undiagnosed? A comparison of two population-based studies in Sweden

OBJECTIVE: To assess the risk of over-diagnosing and over-treating prostate cancer if population-based screening with serum prostate-specific antigen (PSA) is instituted. PATIENTS AND METHODS: From a serum bank stored in 1980, PSA was analysed in 658 men with no previously known prostate cancer from a well-defined cohort from Goteborg, Sweden (men born in 1913); the incidence of clinical prostate

Modeling through drying of tissue-effect of pore size distribution on drying characteristics

A general model for through drying of tissue was developed based on the equations of continuity in combination with correlations for heat and mass transfer. The model incorporates different geometric descriptions together with corresponding heat and mass transfer correlations for flow through cylindrical conduits and flow through packed beds of cylindrical fibers. At low intensities, i.e., at low

Application of the PIV technique to measurements around and inside a forming drop in a liquid–liquid system

A particle image velocimetry (PIV) method has been developed to measure the velocity field inside and around a forming drop with a final diameter of 1 mm. The system, including a microscope, was used to image silicon oil drops forming in a continuous phase of water and glycerol. Fluorescent particles with a diameter of 1 μm were used as seeding particles. The oil was forced through a 200 μm diamet

Area social characteristics and carotid atherosclerosis.

Objectives: To explore the effect of social characteristics of residential areas on carotid atherosclerosis prevalence. Methods and results: The associations among area social characteristics and B-mode ultrasound determined carotid plaque-score (a semi-quantitative scale measuring the degree of atherosclerosis in the carotid bifurcation area) were cross-sectionally investigated in a general popul

Chronic nicotine treatment eliminates asymmetry in striatal glucose utilization following unilateral transection of the mesostriatal dopamine pathway in rats

Partial hemitransection was performed through a knife lesion at the meso-diencephalic level in rats to sever the mesostriatal dopamine system. During the subsequent 2 weeks the animals received 0.125 mg/kg/h of nicotine continuously via an osmotic minipump implanted s.c. To achieve prompt high nicotine levels, 4 i.p. injections of 0.5 mg/kg nicotine were, in addition, given during the first 2 h fo

Saccharomyces kluyveri as a model organism to study pyrimidine degradation.

Abstract The yeast Saccharomyces kluyveri (Lachancea kluyveri), a far relative of Saccharomyces cerevisiae, is not a widely studied organism in the laboratory. However, significant contributions to the understanding of nucleic acid precursors degradation in eukaryotes have been made using this model organism. Here we review eukaryotic pyrimidine degradation with emphasis on the contributions made

End-of-life decision-making in six European countries: descriptive study

Background Empirical data about end-of-life decision-making practices are scarce. We aimed to investigate frequency and characteristics of end-of-life decision-making practices in six European countries: Belgium, Denmark, Italy, the Netherlands, Sweden, and Switzerland. Methods In all participating countries, deaths reported to death registries were stratified for cause (apart from in Switzerland)