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Growth of arbuscular mycorrhizal mycelium in calcareous dune sand and its interaction with other soil microorganisms as estimated by measurement of specific fatty acids

Fatty acid analysis was used for determining the extent of the development of the external mycelium of AM fungi (mixed inoculum from a sand dune) growing from roots of Festuca rubra and Plantago lanceolata in calcareous dune sand. The plants were raised in chambers specially designed to permit the growth of AM mycelium in root-free compartments. In two separate experiments, growth of external myce

Toxic potential of five freshwater Phormidium species (Cyanoprokaryota)

Among the Cyanoprokaryota (blue-green algae), the genus Phormidium has thus far rarely been studied with respect to toxin production and potentially resulting human and environmental health effects. We here show that five previously unexplored freshwater species of this genus (Ph. bijugatum, Ph. molle, Ph. papyraceum, Ph. uncinatum, Ph. autumnale) are indeed capable of producing bioactive compound

The complement: A solution to liquid drop finite size effects in phase transitions

The effects of the finite size of a liquid drop undergoing a phase transition are described in terms of the complement, the largest (but mesoscopic) drop representing the liquid in equilibrium with the vapor. Vapor cluster concentrations, pressure, and density from fixed mean density lattice gas (Ising) calculations are explained in terms of the complement generalization of Fisher's model. Account

Boundary conditions in the envelope function approximation as applied to semiconductor heterostructures: The multi-band case

We have found the equations that determine the self-adjoint extensions, and thus the boundary conditions, of the differential operator used in the multi-band k.p-theory, when the coefficients in the Kane-matrix are piecewise constant. Both the one-dimensional and the three-dimensional case have been investigated. A numerical calculation shows that the choice of boundary conditions affects the ener

Socioeconomic differences in fat intake in a middle-aged population: report from the Malmö Diet and Cancer Study

Background: The objective was to investigate whether socioeconomic differences in fat intake may explain socioeconomic differences in cardiovascular diseases. Methods: The Malm Diet and Cancer Study is a prospective cohort study. The baseline examinations used in the present cross-sectional study were undertaken in 19921994. Dietary habits were assessed using a modified diet history method consist

The predissociation of highly excited states in acetylene by time-resolved photoelectron spectroscopy

We study the dynamics of highly excited states in acetylene initiated by an ultrashort vacuum ultraviolet laser pulse. Electronic states lying in the 4s-3d Rydberg region are excited with one femtosecond pulse, and the dynamic development of the states is monitored by a second short pulse which ionizes the system. We show that even for femtosecond pulses where the bandwidth of the exciting pulse c

Effect of fast CO2 pressure changes on the yield of lovage (Levisticum officinale Koch.) and celery (Apium graveolens L.) extracts

The effect of pressure alterations on the yield of CO2, extracts from different anatomical parts of lovage (Levisticum officinale Koch.) and celery (Apium graveolens L.) was studied. It was found that by applying frequent pressure changes in the extraction vessel it is possible to increase the rate of the isolation of CO2 soluble materials from lovage seeds and leaves, lovage and celery roots. How

A Jurassic (Pliensbachian) flora from Bornholm, Denmark - a study of a historic plant-fossil collection at Lund University, Sweden

A historic collection of plant fossils from the Baga Formation, Bornholm, Denmark registered at the Lund University is reviewed and found to be dominated by ferns with subsidiary Ginkgoales, Coniferales, Bennettitales and Equisitales. Ten genera are represented, of which six can be confidently identified to species level. The Baga Formation flora is most similar in age to the flora of the Middle J

C2-Symmetric Macrocyclic Carbohydrate/Amino Acid Hybrids through Copper(I)-Catalyzed Formation of 1,2,3-Triazoles

An efficient method was developed for the preparation of macrocyclic carbohydrate/amino acid hybrids by macrocyclization with copper(I)-catalyzed 1,2,3-triazole formation. Methyl 2-amino-6-azido-3,4-di-O-benzoyl-2,6-dideoxy--D-glucopyranoside was prepared and coupled to two different N-propiolyl dipeptides (propiolyl-Tyr-Tyr-OH and propiolyl-Arg(Mtr)-Tyr-OH) to obtain bifunctional molecules carryi

A traditional agroforestry system under threat: an analysis of the gum arabic market and cultivation in the Sudan

The main aim of this study is to review the environmental and socioeconomic sustainability of the gum arabic farming system in central Sudan. A further aim is to analyse some of the main factors influencing production in recent decades in order to understand the future trade potential and consequently the smallholder livelihood. The study shows that end-user imports of gum arabic have increased du

Role of chromoendoscopy in colon cancer surveillance in inflammatory bowel disease.

Inflammation in the intestine is a well-known risk factor for neoplastic changes in the mucosa. In fact, it has been shown that long-standing ulcerative colitis and colonic Crohn's disease have a significantly increased risk for developing colorectal cancer, although the estimates vary widely between studies. Conventional colonoscopy is effective in detecting polypoid changes in the mucosa. Howeve

Diesel fuel jet lift-off stabilization in the presence of laser-induced plasma ignition

The mechanisms affecting lift-off stabilization at diesel conditions were investigated by laser-igniting a diesel fuel jet upstream of its natural lift-off position. Single-nozzle fuel sprays penetrating into all optically accessible constant-volume chamber were ignited using laser-induced plasma formation both prior to natural autoignition or after a quasi-steady lift-off length was established.

Four modes of adhesion are used during Helicobacter pylori binding to human mucins in the oral and gastric niches

Background: Helicobacter pylori causes peptic ulcer disease and gastric cancer, and the oral cavity is likely to serve as a reservoir for this pathogen. We investigated the binding of H. pylori to the mucins covering the mucosal surfaces in the niches along the oral to gastric infection route and during gastric disease and modeled the outcome of these interactions. Materials and Methods: A panel o

Species-specificity of Neisseria gonorrhoeae infection: Do human complement regulators contribute?

Neisseria gonorrhoeae is the causative agent of gonorrhea, a disease restricted to humans. Complement forms a key arm of the innate immune system that combats gonococcal infections. N. gonorrhoeae uses its outer membrane porin (Por) molecules to bind complement clown-regulatory proteins, C4b-binding protein (C4BP) and factor H (M), to evade killing by human complement. In addition, sialylation of

Regulation of tissue factor-induced signaling by endogenous and recombinant tissue factor pathway inhibitor 1

Tissue factor (TF) triggers upstream coagulation signaling via the activation of protease-activated receptors (PARs) of relevance for inflammation and angiogenesis. TF pathway inhibitor 1 (TFPI-1) is the physiologic inhibitor of TF-initiated coagulation, but its role in regulating TF signaling is poorly understood. Here, we demonstrate that endogenous, endothelial cell-expressed TFPI-1 controls TF

A Long-Term Perspective on Person-Environment Fit and ADL Dependence Among Older Swedish Adults.

Purpose: This study described person–environment (P–E) fit and activities of daily living (ADLs) among older adults, and it explored the relationship between P–E fit and ADL dependence, testing Lawton's docility hypothesis at two points in time. Design and Methods: From a random sample of individuals aged 75–84 living in a Swedish municipality, 72 persons were available for baseline and follow-up

Energy transport in one-dimensional thermoelectric systems

The efficiency of thermoelectric power generators and the coefficient of performance of thermoelectric refrigerators increase rapidly in the region of small ZT, and then level off to a flat curve in the region of large ZT, where ZT is the figure of merit. Therefore, simply because one-dimensional thermoelectric materials have high ZT predicted theoretically does not imply that efficient thermoelec