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Dissolved organic carbon dynamics in the peat-streamwater interface

A series of experiments were conducted to address the fate of dissolved organic carbon (DOC) in the peat - stream interface zone linking a minerotrophic poor fen and an ombrotrophic mire with surrounding stream water in the drainage area of Lake Ortrasket in northern Sweden. Transport and mineralisation of DOC were quantified in peat - stream interface cores in response to variations in pore water

Mitochondrial damage and dysfunction in traumatic brain injury

The enduring cognitive deficits and histopathology associated with traumatic brain injury (TBI) may arise from damage to mitochondrial populations, which initiates the metabolic dysfunction observed in clinical and experimental TBI. The anecdotal evidence for in vivo structural damage to mitochondria corroborates metabolic and physiologic dysfunction, which depletes substrates and promotes free ra

A pneumococcal pilus influences virulence and host inflammatory responses

Streptococcus pneumoniae (pneumococcus) is a major cause of morbidity and mortality world-wide. The initial event in invasive pneumococcal disease is the attachment of encapsulated pneumococci to epithelial cells in the upper respiratory tract. This work provides evidence that initial bacterial adhesion and subsequent ability to cause invasive disease is enhanced by pili, long organelles able to e

The structure of the Icelandic NP

This paper develops a (QP and a) DP analysis of the Icelandic NP, dealing primarily with prenominal modifiers and postnominal genitives. The paper argues that prenominal quantifiers and determiners head their own projections(QP and DP), whereas attributive adjectives are head-adjoined to nouns. In addition, it is suggested that the minimal NP in morphological case languages, such as Icelandic and

Isolation and characterization of neural precursor cells from the Sox1-GFP reporter mouse.

We have made use of a reporter mouse line in which enhanced green fluorescence protein (GFP) is inserted into the Sox1 locus. We show that the GFP reporter is coexpressed with the Sox1 protein as well as with other known markers for neural stem and progenitor cells, and can be used to identify and isolate these cells by fluorescence-activated cell sorting (FACS) from the developing or adult brain

Seasonal viral loop dynamics in two ultraoligotrophic Antarctic freshwater lakes

The effect of viruses on the microbial loop, with particular emphasis on bacteria, was investigated over an annual cycle in 2003–2004 in Lake Druzhby and Crooked Lake, two large ultraoligotrophic freshwater lakes in the Vestfold Hills, Eastern Antarctica. Viral abundance ranged from 0.16 to 1.56 × 109 particles L-1;1 and bacterial abundances ranged from 0.10 to 0.24 × 109 cells L-1;1, with the low

Bone mineral density and lifestyle among female students aged 16-24 years.

The objective of the study was to investigate bone mineral density and bone turnover among female students aged 16-24 years in relation to lifestyle factors, such as dietary habits and physical activity, as well as physiological factors, such as age, body weight, and menstrual pattern. Female college and university students (n = 218) were given a validated questionnaire with 34 questions concernin

Population trends of farmland birds in Sweden and England: similar trends but different patterns of agricultural intensification

Studies, mainly from the UK, show that many farmland birds have declined as a result of recent agricultural intensification. We tested this idea by analysing farmland bird population trends in Sweden, a country displaying less dramatic agricultural changes and less intensive agriculture. Specifically we investigated whether (i) farmland specialists have declined more than generalists, (ii) populat

Familial related risk-factors in the development of chronic bronchitis/emphysema as compared to asthma assessed in a postal survey

There is a lack of knowledge to which extent heredity or familial risk factors are involved in the development of chronic bronchitis/emphysema (CBE). Smoking is regarded as the most important risk factor, but only about 15% of smokers develop airway obstruction. We evaluated the importance of familial risk factors compared to smoking and ex-smoking using an epidemiological approach. In 1992, a pos

Factors governing the activity of lyophilised and immobilised lipase preparations in organic solvents

Active site titration and activity measurements were performed in hexane on lyophilised lipase preparations containing different amounts of phosphate buffer and lipase immobilised on porous polypropylene. Lyophilisation of Thermomyces lanuginosus lipase with large quantities of phosphate salts (200 mm) increased the specific activity fourfold, and the number of rapidly titratable active sites incr

Sephadex-induced granulomatous alveolitis in rat: effects of antigen manipulation

A granulomatous alveolitis, with multinuclear cell formation combined with an eosinophilic peribronchiolitis, was achieved in rats by intratracheal administration of sephadex beads (G-200, Pharmacia, Sweden). The pattern of inflammation and the degree of postgranulomatous fibrosis were substantially dampened when the particles were dispersed by ultrasonification. The animals were analyzed with bro

Glutamate, but not aspartate, is enriched in trigeminothalamic tract terminals and associated with their synaptic vesicles in the rat nucleus submedius.

To examine the possible roles of glutamate and aspartate as neurotransmitters in the nucleus submedius (Sm) of rats, the distributions of these amino acids were examined by electron microscopic immunogold labeling. High levels of glutamate were detected in trigeminothalamic tract terminals anterogradely labeled with horseradish peroxidase conjugates. These terminals also displayed a positive corre

Adsorption of hydrophobically modified starch at oil/water interfaces during emulsification

The adsorption of starch that had been hydrophobically modified with octenyl succinate anhydride (OSA) at the oil/water interface during emulsification was studied. The starch samples were of waxy barley origin and were varied in molar mass and degree of substitution (DS). The particle size of the emulsions was measured and the adsorbed amount of starch was determined through serum depletion. The

Direct and reverse mechanical modeling of an alkyd acrylic hybrid system: A morphological study

Mechanical modeling and dynamic mechanical analysis were associated to investigate the viscoelastic properties of an alkyd acrylic hybrid system in connection with its morphology, which was characterized by transmission electron microscopy. Theoretical predictions based on the interlayer model used in direct mode were successfully combined with the experimental viscoelastic data to lead to relevan

Thermodynamics and kinetics of a Go(o)over-bar proteinlike heteropolymer model with two-state folding characteristics

We present results of Monte Carlo computer simulations of a coarse-grained hydrophobic-polar G (o) over bar -like heteropolymer model and discuss thermodynamic properties and kinetics of an exemplified heteropolymer, exhibiting two-state folding behavior. It turns out that general, characteristic folding features of realistic proteins with a single free-energy barrier can also be observed in this

Measurements of collisional broadening coefficients by infrared polarization spectroscopy

We present measurements of collisional broadening coefficients, obtained at atmospheric pressure, by polarization spectroscopy. Using tunable single mode laser radiation at similar to 2 pro, high-resolution infrared polarization spectra were recorded for CO2-Ar and CO2-He binary mixtures. The recorded polarization spectra were fitted with a Lorentzian cubed function form to obtain the broadening c

Viscoelastic properties of sodium dodecyl sulfate with aluminum salt in aqueous solution

The rheological properties of wormlike micellar solutions formed by the pseudo-ternary system sodium dodecyl sulfate (SDS)-Al(NO3)(3)-H2O have been studied at a fixed molar ratio Al(NO3)(3):SDS = 5.92:1 as a function of surfactant concentration. The linear data show that solutions behave as a Maxwell fluid and there are two well-defined domains characterized by scaling laws for surfactant concentr

Re-tracing the path to third-order knowledge: How did we get here and can we move on?

The paper argues that policy-oriented educational research, specifically large-scale quantitative research, has produced a new kind of knowledge, which is herein termed third order knowledge. This expect knowledge distinquishes itself from tacit knowledge, everyday knowledge and social science knowledge through its purposes and sources. Third order knowledge is defined as knowledge of and for expe

Concentrations of plasma methylmalonic acid in 80-year-olds show only weak relation to psychological performance

Most studies of the relation between psychological performance in the elderly and deficiencies of cobalamin and folate have used methods that determine the blood concentrations of these vitamins, which might not reflect the vitamin status in the tissues. Recently, two new markers, plasma homocysteine and methylmalonic acid, have attracted growing interest since they are considered to reflect the s