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Polyploid evolution and plastid DNA variation in the Dactylorhiza incarnata/maculata complex (Orchidaceae) in Scandinavia.

The Dactylorhiza incarnata/maculata complex (Orchidaceae) was used as a model system to understand genetic differentiation processes in a naturally occurring polyploid complex with much of ongoing diversification and wide distribution in recently glaciated areas in northern Europe. Data were obtained for 12 hypervariable regions in the plastid DNA genome. A total of 166 haplotypes were found in a

On coded modulation using LDPC convolutional codes

A new construction combining LDPC convolutional codes and multilevel coding/modulation is suggested and analyzed. In the case of QPSK, we demonstrate that it has a better performance than an LDPC convolutional code combined with conventional Gray mapping.

Nanomaterials - Let's twist again

A dislocation running through the trunk of a nanowire offers a new twist to the growth of chiral branched nanostructures, producing beautiful tree-like structures in the process.

Direct observation of the initial-state distribution of the first electron transferred to slow highly charged ions interacting with a metal surface

The electron transfer process in the interaction of a slow highlycharged ion with a metal surface has been studied employing amicrocapillary foil as a target. The combination of the target and avisible light spectroscopy allows us to directly evaluate the initial(n,ℓ) distributions of the first transferred electrons. It wasfound that observed lines were primarily attributed to Δn=1transitions with

Complex Mhc-based mate choice in a wild passerine

The extreme polymorphism of the vertebrate major histocompatibility complex (Mhc) is famous for protecting hosts against constantly evolving pathogens. Mate choice is often evoked as a means of maintaining Mhc variability through avoidance of partners with similar Mhc alleles or preference for heterozygotes. Evidence for these two hypotheses mostly comes from studies on humans and laboratory mice.

Limitations of a pencil beam approach to photon dose calculations in lung tissue

A common limitation in treatment planning systems for photon dose calculation is to ignore the impact on electron transport and photon scatter from patient heterogeneities. The heterogeneity correlation is often based on scaling operations along beam rays as for the method according to Batho or the more novel approach of 1D convolutions along beam paths applied in pencil-beam-based systems. The ef

Transition of the ability to generate petites in the Saccharomyces/Kluyveromyces complex

Petite-positivity - the ability to tolerate the loss of mtDNA - was examined after the treatment with ethidium bromide (EB) in over hundred isolates from the Saccharomyces/Kluyveromyces complex. The identity of petite mutants was confirmed by the loss of specific mtDNA DAPI staining patterns. Besides unequivocal petite-positive and petite-negative phenotypes, a few species exhibited temperature se

Release rates for pine sawfly pheromones from two types of dispensers and phenology of Neodiprion sertifer

Comparisons of release rates, duration in the field, and catch efficiency of polyethylene and cotton roll dispensers for the sex pheromones of sawflies (Hymenoptera: Diprionidae) were conducted. The release rates of the neodiprion sertifer(Geoffr.) and Diprion pini (L.) sex pheromones, the acetates of pentadecanol and (2S,3S,7S)-3,7-dimethyl (2S,3R,7R)-3,7-dimethyl--tridecanol from polyethylene di

Background-free Species Detection In Sooty Flames Using Degenerate 4-wave-mixing

The background radiation disturbance in luminous environments has been compared for degenerate four-wave mixing (DFWM) and laser-induced fluorescence (LIF) for OH radical detection in a sooty propane/oxygen flame. The LIF signal generally was considerably stronger than the DFWM signal, but in strongly sooty environments the LIF signal was accompanied by a significant background signal, while the D

Expression of CD44 and its isoforms in the fetal neuroblasts

CD44 is a polymorphic transmembrane glycoprotein that exists as multiple isoforms resulting from alternative splicing and posttranslational modifications. Enhanced expression of CD44 has been correlated to the tumorigenicity and metastatic behavior in different malignant tumors. In contrast, human neuroblastomas exhibit an inverse correlation between CD44 expression and tumor malignancy. To determ

Globin-expression postpones onset of stationary phase specific gene expression in Escherichia coli

We have analyzed gene expression of Escherichia coli MG1655 expressing native and engineered bacterial globin proteins, in order to identify the molecular mechanisms leading to the improved phenotypical traits relative to control cells under oxygen-limited conditions. Regulated expression of hemoglobin and flavohemoglobin proteins postponed the onset of rpoS expression relative to plasmid bearing

Fatty acid specificity of hormone-sensitive lipase: implication in the selective hydrolysis of triacylglycerols

The selective mobilization of fatty acids from white fat cells depends on their molecular structure, in particular the degree of unsaturation. The present study was designed to examine if the release of fatty acids by hormone-sensitive lipase (HSL) in vitro i) is influenced by the amount of unsaturation, ii) depends on the temperature, and iii) could explain the selective pattern of fatty acid mob

Migratory birds use head scans to detect the direction of the Earth’s magnetic field

Night-migratory songbirds are known to use a magnetic compass [[13]], but how do they detect the reference direction provided by the geomagnetic field, and where is the sensory organ located? The most prominent characteristic of geomagnetic sensory input, whether based on visual patterns [[47]] or magnetite-mediated forces [[8, 9]], is the predicted symmetry around the north-south or east-west mag

In search of selective inhibitors of cysteine protease, cathepsin K

Two potential azapeptide inhibitors of cathepsin K were designed and synthesized. To analyze in detail interactions between these azainhibitors and the investigated cysteine protease, molecular dynamics simulations were performed. For the obtained compounds the equilibrium constants for dissociation of inhibitor-enzyme complex, K-i, were determined. The examined azapeptides proved to be not as pot

Analysis Of Heat Transfer And Transport Processes In Sofcs Involving Internal Reforming Reactions

The heat transfer rates in solid oxide fuel cells (SOFCs) are controlled by various operating and design parameters and have significant effects on chemical reactions and coupled transport processes. In this article, the considered composite duct consists of a porous anode layer for the internal reforming reactions of methane, the fuel gas flow duct, and the solid plate. A fully three-dimensional

Regulations and practices of genetic counselling in 38 European countries: the perspective of national representatives

The aim of this article is to review the national regulations and practices of genetic counselling in 38 European countries, and to examine how well they intersect the ideals of genetic counselling defined in international guidelines. Using an electronic survey, representatives of the National Societies of Human Genetics in 29 countries, and appropriate contact persons for the field of genetic cou