Testing the applicability of dendrochemistry using X-ray fluorescence to trace environmental contamination at a glassworks site.

The potential of dendrochemistry as a tool for tracing anthropogenic contamination at a glassworks site in southeastern Sweden was investigated through a multidisciplinary approach combining continuous high-resolution time series of tree rings and sediment profiles. Tree cores from Scots pine (Pinus sylvestris), Norway spruce (Picea abies) and European aspen (Populus tremula) were analysed for their elemental composition using an energy dispersive X-ray fluorescence (ED-XRF) technique. Sediment cores were sampled along a transect extending from the pollution point source to unpolluted areas and analysed using core-scanning-XRF (CS-XRF).

Sulfur and iron accumulation in three marine-archaeological shipwrecks in the Baltic Sea: the Ghost, the Crown and the Sword.

Sulfur and iron concentrations in wood from three 17(th) century shipwrecks in the Baltic Sea, the Ghost wreck, the Crown and the Sword, were obtained by X-ray fluorescence (XRF) scanning. In near anaerobic environments symbiotic microorganisms degrade waterlogged wood, reduce sulfate and promote accumulation of low-valent sulfur compounds, as previously found for the famous wrecks of the Vasa and Mary Rose. Sulfur K-edge X-ray absorption near-edge structure (XANES) analyses of Ghost wreck wood show that organic thiols and disulfides dominate, together with elemental sulfur probably generated by sulfur-oxidizing Beggiatoa bacteria.

Dendrochemistry of multiple releases of chlorinated solvents at a former industrial site.

Trees can take up and assimilate contaminants from the soil, subsurface, and groundwater. Contaminants in the transpiration stream can become bound or incorporated into the annual rings formed in trees of the temperate zones. The chemical analysis of precisely dated tree rings, called dendrochemistry, can be used to interpret past plant interactions with contaminants.

Sedimentation and chronology of heavy metal pollution in Oslo harbor, Norway.

Stratigraphic profiles of Cu, Cd and Hg in ten sediment cores from the Oslo harbor, Norway, combined with results of radiometric dating demonstrate that pollution by these metals peaked between 1940 and 1970. Dating results indicate that Hg discharges peaked between 1940 and 1950, Cd reached maximum ca. 1955-1960, and Cu has the highest concentration in sediment interval corresponding to ca.

Microdiffraction studies of bone tissues using synchrotron radiation.

This is the first report on a series of studies of the crystallinity of bone tissues. The measurements were done at the microfocused diffraction beamline at ERSF (European Synchrotron Radiation Facility) as a feasibility test on various aspects on microdiffraction analysis. Beside the crystal structure, crystallite size distribution and preferential orientation were also studied, with a spatial resolution of 7 microm.

The use of a scanning X-ray microprobe for simultaneous XRF/XRD studies of fly-ash particles.

With the opening of the first real ;third-generation' synchrotron source in Grenoble, in fall 1994, X-ray sources of unprecedented brilliances and qualities became available to the scientific community. Different X-ray analytical techniques could now be applied on a level that was unimaginable only a decade ago. Here are some preliminary results from an experiment where different analytical techniques have been applied on a micrometer level carried out at the most powerful synchrotron microbeam currently available in the world, the microfocus beamline (BL1) at ESRF.

Myotonic dystrophy treated with selenium and vitamin E.

We have previously reported the successful treatment of a patient with myotonic dystrophy with selenium and vitamin E. This paper deals with the treatment of a further five patients with myotonic dystrophy in different stages. All five patients improved subjectively and objectively in two or more respects.

Selenium, zinc, iron and copper levels in serum of patients with arterial and venous leg ulcers.

The total serum concentrations of selenium, zinc, iron and copper were determined in geriatric patients with and without leg ulcers. The levels of selenium, zinc and iron were significantly lower and the copper/zinc ratio was significantly higher in the leg ulcer group compared with control patients. The serum-copper level and the serum-copper/zinc ratio were raised in patients with poor ulcer healing.

Selenium therapy of myotonic dystrophy.

A patient with myotonic dystrophy (MD) has been treated for two years with selenium and vitamin E. The serum selenium concentration and other relevant variables were continuously studied. The patient showed a marked subjective and objective improvement with increased muscular strength and regression of pathological electromyographic findings.

Metal analysis by energy dispersive x-ray fluorescence of bovine brain tubulin and microtubule-associated proteins prepared by phosphocellulose chromatography.

It has been shown by trace metal analysis that tubulin isolated from bovine brain does not contain strongly bound transition metal ions. The traces of zinc and iron found in the fraction of microtubule-associated proteins might originate from previously reported phosphatase activity (Larsson, H., Wallin, M.