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Vertical distribution of microfungi in a spruce forest soil in south of Sweden

Soil-washing technique was used for the isolation of microfungi from soil of a planted Norway spruce forest in the south of Sweden. About ninety different fungal species were identified. The most frequently isolated genera were Mortierella, Penicillium, and Trickoderma which together constituted 71% of the total number of isolates. A significant (P < 0·01) difference in abundance between the diffe

Production of a lipolytic enzyme originating from Bacillus halodurans LBB2 in the methylotrophic yeast Pichia pastoris

A gene encoding a lipolytic enzyme amplified from the alkaliphilic bacterium Bacillus halodurans LBB2 was cloned into the pPICZ alpha B vector and integrated into the genome of the protease deficient yeast strain Pichia pastoris SMD1168H. This previously undescribed enzyme was produced in active form, and cloning in frame with the Saccharomyces cerevisiae secretion signal (alpha-factor) enabled ex

Compressibility of lubricants at high pressures

Results from a high pressure chamber; recently developed at Lund Institute of Technology, are presented. The compressibility variation with the pressure of five different lubricants is investigated for pressures up to 2.7 GPa. The density variation for each lubricant is presented as a curve fit. The results show that at high pressures when the lubricant has solidified, the density varies linearly

Tobacco smoking increases the risk for gastric adenocarcinoma among Helicobacter pylori-infected individuals

BACKGROUND: The importance of tobacco smoking and Helicobacter pylori infection as risk factors in the development of gastric carcinoma was investigated through multivariate conditional logistic regression analysis in a nested case-control study. METHODS: Blood samples and a questionnaire on smoking habits were collected from a cohort of 32,906 city residents during a health screening programme fr

Ultrathin ZrO2 films on Si-rich SiC(0001)-(3x3): Growth and thermal stability

The growth and thermal stability of ultrathin ZrO2 films on the Si-rich Si(0001)-(3 x 3) surface have been explored using photoelectron spectroscopy (PES) and X-ray absorption spectroscopy (XAS). The films were grown in situ by chemical vapor deposition using the zirconium tetra tert-butoxide (ZTB) precursor. The O 1s XAS results show that growth at 400 degrees C yields tetragonal ZrO2. An interfa

Numerical solution of fractional advection-dispersion equation

Numerical schemes and stability criteria are developed for solution of the one-dimensional fractional advection-dispersion equation (FRADE) derived by revising Fick's first law. Employing 74 sets of dye test data measured on natural streams, it is found that the fractional order F of the partial differential operator acting on the dispersion term varies around the most frequently occurring value o

Enhancement of poorly edible phytoplankton by allochthonous dissolved organic material: a modelling study

The effect of different input rates of dissolved inorganic (DIN) and organic (DON) nitrogen on a microbial food web was studied with the help of a mathematical model. Three species of phytoplankton were modelled, with trade-off characteristics for maximum per capita growth rate, half-saturation constant and edibility. Bacteria used only DON, while 2 different types of microzooplankton grazed on th

The meaning of quality work from the general practitioner's perspective: an interview study

BACKGROUND: The quality of health care and its costs have been a subject of considerable attention and lively discussion. Various methods have been introduced to measure, assess, and improve the quality of health care. Many professionals in health care have criticized quality work and its methods as being unsuitable for health care. The aim of the study was to obtain a deeper understanding of the

Methods in cell separations

Research in the field of cell biology and biomedicine relies on technologies that fractionate cell populations and isolate rare cell types to high purity. A brief overview of methods and commercially available products currently used in cell separations is presented. Cell fractionation by size and density and highly selective affinity-based technologies such as affinity chromatography, fluorescenc

Power mapping and noise reduction for financial correlations

The spectral properties of financial correlation matrices can show features known from completely random matrices. A major reason is noise originating from the finite lengths of the financial time series used to compute the correlation matrix elements. In recent years, various methods have been proposed to reduce this noise, i.e. to clean the correlation matrices. This is of direct practical relev

Job strain in men, but not in women, predicts a significant rise in blood pressure after 6.5 years of follow-up.

Background: Job strain (high demands and low decision latitude) has been associated with hypertension and cardiovascular disease, especially in men. Most studies on job strain and hypertension have been cross-sectional, and prospective data are inconsistent. Objective: To prospectively describe the effects of different psychosocial work characteristics on office blood pressure changes. Methods: In