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Evolutionary dynamics of mitochondrial plasmids in natural populations of Silene vulgaris

Although plasmid-like mitochondrial DNA molecules have been investigated in a number of cultivated plant species, knowledge about their occurrence and behavior in natural plant populations is scarce. In the bladder campion, Silene vulgaris, a common weed of northern Europe, mt-plasmids of three different sizes were detected in a survey of S. vulgaris populations in southern Sweden. Two of the thre

Bradykinin-induced airflow obstruction and airway plasma exudation: effects of drugs that inhibit acetylcholine, thromboxane A2 or leukotrienes

1 The mechanisms behind bradykinin-induced effects in the airways are considered to be largely indirect. The role of cholinergic nerves and eicosanoids, and their relationship in these mechanisms were investigated in guinea-pigs. 2 The role of cholinergic nerves was studied in animals given atropine (1 mg kg-', i.v.), hexamethonium (2 mg kg-', i.v.), or vagotomized. To study the role of eicosanoid

Implicit integration of plasticity models for granular materials

A stress integration algorithm for granular materials based on fully implicit integration with explicit updating is presented. In the implicit method the solution makes use of the gradient to the potential surface at the final stress state which is unknown. The final stress and hardening parameters are determined solving the non-linear equations iteratively so that the stress increment fulfills th

Lysozyme adsorption to charged surfaces. A Monte Carlo study

Lysozyme adsorption to charged surfaces was studied by Monte Carlo simulations at different protein concentrations, protein net charges, ionic strengths, and surface charge densities. The lysozyme was represented by a hard sphere with embedded positive and negative surface charges parametrically dependent on the solution pH. A short-range attractive protein-protein potential was included to repres

Maximum slope convolutional codes

The slope is an important distance parameter for a convolutional code. It can be used to obtain a lower bound on the active burst distance and in this respect essentially determines the error-correcting capability of the code. An upper bound on the slope of rate R = b/c convolutional codes is derived. A new family of convolutional codes, called the maximum slope (MS) code family, is introduced. Ta

Biphasic differential changes of GABAA receptor subunit mRNA levels in dentate gyrus granule cells following recurrent kindling-induced seizures

GABAA receptor alpha 1, beta 3 and gamma 2 subunit mRNA levels have been measured in hippocampus using in situ hybridization, following 1, 10 and 40 seizures produced by rapid kindling stimulations. Major alterations of gene expression were largely confined to the dentate gyrus. One stimulus-induced seizure reduced gamma 2 mRNA levels in the dentate gyrus by 30%. In contrast, mRNA expression incre

Exploring light-cone sum rules for pion and kaon form factors

We analyze the higher-twist effects and the SU(3)-flavor symmetry breaking in the correlation functions used to calculate form factors of pseudoscalar mesons in the QCD light-cone sum rule approach. It is shown that the Ward identities for these correlation functions yield relations between twist-4 two-and three-particle distribution amplitudes. In addition to the relations already obtained from t

Adsorption of lithium on the Si(111)7 × 7 surface studied with high resolution core-level spectroscopy

Li-adsorption on the Si(111)7 × 7 surface at room temperature has been studied for different metal coverages with core-level spectroscopy. Four Li-induced components are observed in the Si 2p level at high Li-coverages indicating the formation of four thermodynamically stable phases. It is shown that the reaction between the Li atoms and the Si(111)7 × 7 surface takes place in two steps. In the fi

Quantification, of photosystem I and II in different parts of the thylakoid membrane from spinach

Abstract: Electron paramagnetic resonance (EPR) was used to quantify Photosystem I (PSI) and PSII in vesicles originating from a series of well-defined but different domains of the thylakoid membrane in spinach prepared by non-detergent techniques. Thylakoids from spinach were fragmented by sonication and separated by aqueous polymer two-phase partitioning into vesicles originating from grana and

A 5-hydroxymethyl furfural reducing enzyme encoded by the Saccharomyces cerevisiae ADH6 gene conveys HMF tolerance

The fermentation of lignocellulose hydrolysates by Saccharomyces cerevisiae for fuel ethanol production is inhibited by 5-hydroxymethyl furfural (HMF), a furan derivative which is formed during the hydrolysis of lignocellulosic materials. The inhibition can be avoided if the yeast strain used in the fermentation has the ability to reduce HMF to 5-hydroxymethylfurfuryl alcohol. To enable the identi

XAFS experiments at beamline I811, MAX-lab synchrotron source, Sweden

A description of a new facility for X-ray absorption spectroscopy at the materials science beamline, I811, at MAX-lab synchrotron source, Lund, Sweden, is given. The beamline is based on a superconducting multipole wiggler source inserted in a straight section of the 1.5 GeV MAX-II ring. X-rays in the energy range 2.4- 12 keV are extracted by a standard optical scheme consisting of a vertical coll