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Gas detection by correlation spectroscopy employing a multimode diode laser

A gas sensor based on the gas-correlation technique has been developed using a multimode diode laser (MDL) in a dual-beam detection scheme. Measurement of CO2 mixed with CO as an interfering gas is successfully demonstrated using a 1570 run tunable MDL. Despite overlapping absorption spectra and occasional mode hops, the interfering signals can be effectively excluded by a statistical procedure in

Ordovician limestone in Hälsingland, Sweden

Limestone boulders of Early and Middle Ordovician age occur along the Baltic coast of Sweden from c. 59 degrees N to c. 62.5 degrees N, apparently at a considerable distance from any known source rocks on land. We have investigated a limestone block from Lake Kultebo, at 61 degrees N, not far inland. The conodont elements enclosed in the rock are of Mid-Ordovician age and show that the block could

What's the story? Narration and comprehension in Swedish preschool children with language impairment

This study investigated the possibility of identifying narrative problems at an early age (5-year-old children with language impairment). Furthermore, we explored the relationship between the comprehension of a story and the ability to structure the contents of the same story in a group of preschool children with language impairment. The results showed that the participants did not exhibit age-app

Mechanism of CO oxidation reaction on O-covered Pd(111) surfaces studied with fast x-ray photoelectron spectroscopy: Change of reaction path accompanying phase transition of O domains

We studied the mechanism of CO oxidation on O-precovered Pd(111) surfaces by means of fast x-ray photoelectron spectroscopy (XPS). The oxygen overlayer is compressed upon CO coadsorption from a p(2x2) structure into a (root 3x root 3)R30 degrees structure and then into a p(2x1) structure with increasing CO coverage. These three O phases exhibit distinctly different reactivities. (1) The p(2x2) pha

The Strengths and Difficulties Questionnaire as a screening instrument in a community sample of high school seniors in Sweden

The Strengths and Difficulties Questionnaire (SDQ) has been used among Swedish children since 1996, usually the parent or the teacher version. The self-report version was originally developed for children aged 11-16 years. The aim of this study was to investigate the application of the Swedish self-report version to a representative sample of 1015 senior high school students aged 17-19 years. Girl

Neuropeptide Y inhibits in vitro epileptiform activity in the entorhinal cortex of mice.

Previous studies show that neuropeptide Y (NPY) inhibits in vitro seizures in rodent hippocampus. Here, we explored the effect of NPY application on epileptiform discharges induced by perfusion with magnesium-free solution in slices of entorhinal cortex from two different mouse strains. NPY significantly reduced the duration of epileptiform discharges with a peak effect of 36–50%. This is the firs

Renal function exerts only a minor influence on high plasma homocysteine concentrations in patients with acute coronary syndromes.

It has been suggested that hyperhomocysteinemia observed in patients with occlusive vascular disease is caused by reduced renal function secondary to renovascular disease. We have therefore used serum cystatin C, a new sensitive marker for glomerular filtration, in 59 patients with acute coronary syndromes and high plasma homocysteine (tHcy) concentration to measure renal function. Samples were al

Cellular sterol ester synthesis in plants is performed by an enzyme (phospholipid:sterol acyltransferase) different from the yeast and mammalian acyl-CoA:sterol acyltransferases

A gene encoding a sterol ester-synthesizing enzyme was identified in Arabidopsis. The cDNA of the Arabidopsis gene At1g04010 (AtPSAT) was overexpressed in Arabidopsis behind the cauliflower mosaic virus 35S promoter. Microsomal membranes from the leaves of overexpresser lines catalyzed the transacylation of acyl groups from phosphatidylethanolamine to sterols. This activity correlated with the exp

Acid sphingomyelinase is induced by butyrate but does not initiate the anticancer effect of butyrate in HT29 and HepG2 cells

Butyric acid and sphingomyelin (SM) affect colonic tumorigenesis. We examined the potential link between butyrate stimulation and SM metabolism in colonic and hepatic cancer cell lines. After incubating HT29 and HepG2 cells with butyrate and other short-chain fatty acids, we found that butyrate increased acid but not neutral or alkaline sphingomyelinase (SMase) activity by 10- to 20-fold. The effe

Tissue temperature measurements during interstitial laser therapy using Cr3+-doped crystals at the fiber tip

In this project a technique to optically measure the temperature is evaluated. The measurement is to be performed through optical fibres during photodynamic laser treatments or laser thermo therapy of malignant tumours. For this technique Cr3+-doped crystals were used. The lifetime of the ions' fluorescence were measured, since the fluorescence is strongly temperature dependent. A piece of a cryst

A model for the topology of the chloroplast thylakoid membrane

A model for the topological organization of the chloroplast thylakoid membrane is presented. A series of illustrations is provided, which outline a suggested 3-dimensional structure in cross-section and in full shape, which accounts both for the folding of one continuous membrane into multiple grana stacks as seen in cross-sectional electron micrographs and for the rapid reversible unfolding (dest

Secondary Metabolites from Heliotropium angiospermum

Blumenol A (1), blumenol B (2) and loliolide (3), together with the ubiquitous beta-sitosterol, alpha-amyrin and beta-amyrin, were isolated from the organic extract of the leaves of Heliotropium angiospermum. Structural elucidation of the metabolites was carried out by analysis of their spectroscopic data and/or by comparison with those reported in the literature.

Further important sensitizers in patients sensitive to fragrances - II. Reactivity to essential oils

In order to find sensitizers additional to the current fragrance mix (FM) a series of fragrance materials (series II) was evaluated in 6 dermatological centres in Europe. 11 of the test materials were essential oils, the remaining 7 being either mixtures of isomers or simple chemicals of frequent usage in the perfume industry. 1606 patients were consecutively tested with series II and 8% FM. Each

Delayed infusion of GDNF promotes recovery of motor function in the partial lesion model of Parkinson's disease

Here we studied the effects of glial cell line-derived neurotrophic factor (GDNF) in a rat model that represents the symptomatic stages of Parkinson's disease. GDNF was infused starting 2 weeks after an intrastriatal 6-hydroxydopamine (6-OHDA) lesion in order to halt the ongoing degeneration of the nigrostriatal dopaminergic neurons. GDNF or vehicle was infused in the striatum or the lateral ventr

Physiological, morphological and behavioural effects of selecting zebra finches for divergent levels of corticosterone

The effects of environmental stress on the physiology and behaviour of higher vertebrates has become an important avenue of research in recent years. Evidence from recent studies has suggested that the avian stress-related hormone corticosterone (CORT) may play a role in immunocompetence and sexual selection. We tested whether CORT is immunosuppressive by studying humoral and cell-mediated immune