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Production, standing biomass and natural abundance of N-15 and C-13 in ectomycorrhizal mycelia collected at different soil depths in two forest types

Nutrient uptake by forest trees is dependent on ectomycorrhizal (EM) mycelia that grow out into the soil from the mycorrhizal root tips. We estimated the production of EM mycelia in root free samples of pure spruce and mixed spruce-oak stands in southern Sweden as mycelia grown into sand-filled mesh bags placed at three different soil depths (0-10, 10-20 and 20-30 cm). The mesh bags were collected

Oxidized low-density lipoprotein induces calpain-dependent cell death and ubiquitination of caspase 3 in HMEC-1 endothelial cells.

Oxidized low-density lipoprotein (oxLDL) is known to induce apoptosis in endothelial cells, and this is believed to contribute to the progression of atherosclerosis. In the present study we made the novel observation that oxLDL-induced death of HMEC-1 cells is accompanied by activation of calpain. The mu-calpain inhibitor PD 151746 decreased oxLDL-induced cytotoxicity, whereas the general caspase

The function of genomes in bioenergetic organelles.

Mitochondria and chloroplasts are energy-transducing organelles of the cytoplasm of eukaryotic cells. They originated as bacterial symbionts whose host cells acquired respiration from the precursor of the mitochondrion, and oxygenic photosynthesis from the precursor of the chloroplast. The host cells also acquired genetic information from their symbionts, eventually incorporating much of it into t

Cloning and characterization of a promoter flanking the early B cell factor (EBF) gene indicates roles for E-proteins and autoregulation in the control of EBF expression.

The early B cell factor (EBF) is a transcription factor shown crucial for the development of B lymphocytes. The protein is expressed from the earliest stages of B cell development until the mature B cell stage, but the control elements responsible for the regulation of the gene are unknown. In this study, we report of the identification of a promoter region flanking the EBF gene. Several transcrip

An adaptive impedance tuning CMOS circuit for ISM 2.4-GHz band

The difficulties encountered in matching an antenna to its optimal impedance are reduced with an adaptive 0.35-mu m CMOS circuit based on several switched shunt capacitors arranged in capacitor banks and on a few external series inductors. As high-quality inductors are difficult to obtain in CMOS, the inductors are placed either in an low-temperature cofired ceramic (LTCC) substrate or is a lumped

On the influence of the basis set superposition error on calculated vibrational frequencies

The relation between the so called basis set superposition error and intramolecular vibrational frequencies calculated at the Hartree Fock SCF level of approximation was investigated. A linear conformation of HF dimer was chosen as test system for the investigation. It was found that the direct basis set superposition error for the studied system is rather small. It was further found that the shif

The mechanism of SR95531 inhibition at GABA receptors examined in human alphabeta and alphabetagamma receptors.

We examined the interaction of GABA and the competitive inhibitor SR95531 at human α1β1γ2S and α1β1 GABAA receptors expressed in Sf9 cells. The efficacy and potency of inhibition depended on the relative timing of the GABA and SR95531 applications. In saturating (10 mm) GABA, the half-inhibitory concentrations of SR95531 (IC50) when coapplied with GABA to α1β1γ2S or α1β1 receptors were 49 and 210

Analysis of PEM Fuel Cell Stacks and Systems with Water/Thermal Balances

The Proton Exchange Membrane (PEM) fuel cell has been investigated for a long time, and is regarded as a new energy source for various applications, such as portable, stationary and automotive ones. However, due to the shortage of the infrastructure in the society, the high cost, the difficulty of the water/thermal management, etc., practical systems have not reached the general public, yet. Of t

In situ visualization of the effect of a pulsed electric field on plant tissue

A new method was developed for in situ visualization of changes related to electropermeabilization of plant tissue. Onion epidermis stained with neutral red was subjected to a pulsed electric field (PEF), and serial images were captured by a camera connected to a stercomicroscope. Sample resistance was recorded simultaneously. Above a threshold level of a field strength of 0.35 kV/cm, it was possi

Epididymal and accessory sex gland function and semen quality

Infertility, defined as the inability to conceive after one year of unprotected regular intercourse, affects up to 15% of all couples of reproductive age. The infertility can originate from female, male or both partners. In up to 50% of the affected couples, a male factor is the cause of infertility. Semen analysis is the cornerstone of male infertility assessment and an abnormal result often trig

Unusual process of water formation on RuO2(110) by hydrogen exposure at room temperature

The reduction mechanism of the RuO2(110) surface by molecular hydrogen exposure is unraveled to an unprecedented level by a combination of temperature programmed reaction, scanning tunneling microscopy, high-resolution core level shift spectroscopy, and density functional theory calculations. We demonstrate that even at room temperature hydrogen exposure to the RuO2(110) surface leads to the forma

Determination of polybrominated diphenyl ethers at trace levels in environmental waters using hollow-fiber microporous membrane liquid-liquid extraction and gas chromatography-mass spectrometry

In this study, we present a simple and easy-to-use extraction method that is based on a hollow-fiber microporous membrane liquid-liquid extraction (HF-MMLLE), as an extraction technique, followed by gas chromatography-mass spectrometry (GC-MS) to determine a group of brominated flame retardants (BFRs), polybrominated diphenyl ethers (PBDEs), at trace levels in aqueous samples. The hollow-fiber mem

Reproductive investment of a lacertid lizard in fragmented habitat

We studied the effect of habitat fragmentation on female reproductive investment in a widespread lacertid lizard (Psammodromus algirus) in a mixed-forest archipelago of deciduous and evergreen oak woods in northern Spain. We captured gravid females in fragments (= 200 ha) and brought them to the laboratory, where they laid their eggs. We incubated the eggs and released the first cohort of juvenile

The 5f(3) manifold of the free-ion U3+ : Ab initio calculations

The energy levels of the 5f(3) manifold of the free-ion U3+ Up to 30 000 cm(-1) are calculated with two well stabilized ab initio methods based on the two-component Hamiltonians of Cowan-Griffin-Wood-Boring and Douglas-Kroll-Hess. Although the corresponding experimental data do not exist, estimates made out of experiments on the 50 manifold of U3+ in solids are usually referred to as the experimen

Past incidence and future demand for knee arthroplasty in Sweden: a report from the Swedish Knee Arthroplasty Register regarding the effect of past and future population changes on the number of arthroplasties performed

By combining data from the Swedish Knee Arthroplasty Register and Swedish census registers we have calculated the past age-specific incidence of primary knee arthroplasties and predicted the demand. During the last 20 years, osteoarthrosis has accounted for the largest increase in number of knee arthroplasties while operations for rheumatoid arthritis remained constant. The mean yearly number of o