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This pilot study highlights the substantial potential of using isotopically enriched (non-radioactive) metals to study the fate of biodegradable metal implants. It was possible to show that magnesium (Mg) release can be observed by combining isotopic mass spectrometry and isotopic pattern deconvolution for data reduction, even at low amounts of Mg released a from slowly degrading 26 Mg enriched (>99%) Mg metal. Following implantation into rats, structural in vivo changes were monitored by μCT. Results showed that the applied Mg had an average degradation rate of 16 ± 5 μm year −1 , which corresponds with the degradation rate of pure Mg. Bone and tissue extraction was performed 4, 24, and 52 weeks after implantation. Bone cross sections were analyzed by laser ablation inductively coupled plasma mass spectrometry (ICP-MS) to determine the lateral 26 Mg distribution. The 26 Mg/ 24 Mg ratios in digested tissue and excretion samples were analyzed by multi collector ICP-MS. Isotope pattern deconvolution in combination with ICP-MS enabled detection of Mg pin material in amounts as low as 200 ppm in bone tissues and 20 ppm in tissues up to two fold increased Mg levels with a contribution of pin-derived Mg of up to 75% (4 weeks) and 30% (24 weeks) were found adjacent to the implant. After complete degradation, no visual bone disturbance or residual pin-Mg could be detected in cortical bone. In organs, increased Δ 26 Mg/ 24 Mg values up to 16‰ were determined compared to control samples. Increased Δ 26 Mg/ 24 Mg values were detected in serum samples at a constant total Mg level. In contrast to urine, feces did not show a shift in the 26 Mg/ 24 Mg ratios. This investigation showed that the organism is capable of handling excess Mg well and that bones fully recover after degradation. Statement of Significance Magnesium alloys as bone implants have faced increasing attention over the past years. In vivo degradation and metabolism studies of these implant materials have shown the promising application in orthopaedic trauma surgery. With advance in Mg research it has become increasingly important to monitor the fate of the implant material in the organism. For the first time, the indispensible potential of isotopically enriched materials is documented by applying 26 Mg enriched Mg implants in an animal model. Therefore, the spatial distribution of pin-Mg in bone and the pin-Mg migration and excretion in the organism could be monitored to better understand metal degradation as well as Mg turn over and excretion.

An interdisciplinary study, involving geologists, chemists and pedologists, started aiming at identifying a "Geo-Pedo-Fingerprint" (GPF) univocally linking the wine to its origin, namely, the Piedirosso vineyards growing in the Campi Flegrei volcanic area. The focal point of this research was the characterization of the whole parent material-soil-vineyard-wine system, achieved by correlating the elemental pattern - with special reference to micro-nutrients and Rare Earth Elements (REEs) - and Sr isotopic ratios, to identify a reliable and convenient 'GPF', as a guaranteed indicator of wine provenance. A representative soil/Piedirosso vineyard system was identified and characterized. Samples from each soil horizon as well as from vine branches, leaves, grapes and wine were collected and analyzed. All samples were analyzed by multi-collector inductively coupled mass spectrometry (MC-ICPMS) to determine their 87Sr/86Sr isotopic composition, by ICP-Quadrupole MS to measure multi-elemental composition including REE, and by X-Ray Powder Diffraction (XRPD) for the quantitative evaluation of the mineral phases occurring in soil samples.Statistical analysis (Hierarchical Cluster Analysis, Factor Analysis) revealed the existence of separate correlations of element distribution between: i) soil, as nutrient pool source, and vegetative compartments, i.e. branches and leaves, as biochemical yards for nutrient elaboration and marshaling, ii) vegetative compartments and the productive compartment, i.e. grapes as the metabolic outcome of the vine, and, iii) the productive compartment and its artifact produced by man, i.e. wine. However, no sequential correlation of elements from soil to wine did appear, likely because clusters of elements were discriminated due to the varying takeup and fractionation processes in plants, as well as during vinification processes. Therefore, none of the investigated elements was a liable 'GPF' as a candidate tracer from soil to wine.In contrast, the use of a petrogenetic tracer such as 87Sr/86Sr isotopic composition provided satisfactory responses. In fact, the values of such a ratio within the entire studied chain vary in a very small range from 0.7076 to 0.7084, thus falling within the typical range for volcanites of Campi Flegrei (0.7065-0.7086). These results currently represent the only study focusing on a geotracer, such as the 87Sr/86Sr isotopic ratio, linked with a pedological survey to identify the volcanic Campanian wine-producing chains from soil parent material-to-wine. © 2013 Elsevier B.V.

This study is dedicated to the systematic investigation of the effect of interferences on Sr isotopic analyses in biological apatite and carbonate matrices using laser ablation multicollector inductively coupled plasma mass spectrometry (LA-MC ICP-MS). Trends towards higher 87 Sr/ 86 Sr ratios for LA-MC ICP-MS compared to solution-nebulization based MC ICP-MS when analysing bioapatite matrices (e.g. human teeth) and lower ratios in case of calcium carbonates (e.g. fish ear stones) were observed. This effect can be related to the presence of significant matrix-related interferences such as molecular ions (e.g. ( 40 Ca- 31 P- 16 O) + , ( 40 Ar- 31 P- 16 O) + , ( 42 Ca- 44 Ca) + , ( 46 Ca 40 Ar) + ) as well as in many cases concomitant atomic ions (e.g. 87 Rb + , 174 Hf 2 + ). Direct 87 Sr/ 86 Sr ratio measurements in Ca-rich samples are conducted without the possibility of prior sample separation, which can be accomplished routinely for solution-based analysis. The presence of Ca-Ar and Ca-Ca molecular ion interferences in the mass range of Sr isotopes is shown using the mass resolving capabilities of a single collector inductively coupled plasma sector field mass spectrometer operated in medium mass resolution when analysing bioapatites and calcium carbonate samples. The major focus was set on analysing human tooth samples, fish hard parts and geological carbonates. Potential sources of interferences were identified and corrected for. The combined corrections of interferences and adequate instrumental isotopic fractionation correction procedures lead to accurate data even though increased uncertainties have to be taken into account. The results are discussed along with approaches presented in literature for data correction in laser ablation analysis.

We report on the long-term effects of degrading magnesium implants on bone tissue in a growing rat skeleton using continuous in vivo micro-Computed Tomography, histological staining and Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS). Two different magnesium alloys—one rapidly degrading (ZX50) and one slowly degrading (WZ21)—were used to evaluate the bone response and distribution of released Mg and Y ions in the femur of male Sprague-Dawley rats. Regardless of whether the alloy degrades rapidly or slowly, we found that bone recovers restitutio ad integrum after complete degradation of the magnesium implant. The degradation of the Mg alloys generates a significant increase in Mg concentration in the cortical bone near the remaining implant parts, but the Mg accumulation disappears after the implant degrades completely. The degradation of the Y-containing alloy WZ21 leads to Y enrichment in adjacent bone tissues and in newly formed bone inside the medullary space. Locally high Y concentrations suggest migration not only of Y ions but also of Y-containing intermetallic particles. However, after the full degradation of the implant the Y-enrichment disappears almost completely. Hydrogen gas formation and ion release during implant degradation did not harm bone regeneration in our samples., Acta Biomaterialia, 42, ISSN:1742-7061, ISSN:1878-7568

53 metallic elements from smartphones were investigated with regard to metal prices, metal production, and content in comparison to mined ores. The metal content of the 7.42 billion smartphone devices sold from 2012 to 2017 could theoretically maintain the global supply for 91 days for Ga, 73 days for Ta, 23 days for Pd, 14 days for Au, and 6 days for REE. The pure metal value of a single smartphone device for the investigated metals currently sums to 1.13 US $; it averaged at 1.05 US $ from 2012 to 2017 with the highest value of 1.32 US $ in 2012. The Au content is low (16.83 mg per device), yet constitutes the highest value with a current share of approximately 72% of total value for all measured metals, followed by Pd (10%). Approximately 82% of total metal value can be recycled with current standard recycling methods for Au, Cu, Pd, Pt, which only comprise 6 wt% of the total device. The printed circuit board (pcb) contains 90% of the measured Au, 98% of Cu, 99% of Pd, 86% of In, and 93% of Ta. The Au, Pd, Cu, Pt, Ta, In, Ga contents in a smartphone pcb are significantly higher than the metal content in currently mined ores. Magnets contain 96% of the measured REE and 40% of the measured Ga, with higher concentrations than ores for REE and Ga. For Co and Ge, metal content in smartphones (w/o batteries) is lower than in ores.

Trace element concentrations in the rhizosphere were quantified to better understand why soil liming often fails to reduce cadmium (Cd) uptake by plants. Maize seedlings were grown on a soil with natural background levels of Cd and zinc (Zn). Soil liming increased soil pH from 4.9 to 6.5 and lowered the soil solution free ion activities by factor 7 (Cd) and 9 (Zn). In contrast, shoot Cd concentrations were unaffected by liming while shoot Zn concentrations were lowered by factor 1.9. Mapping of labile soil trace elements using diffusive gradients in thin films (DGT) in combination with laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) revealed an almost complete depletion of Cd in the rhizosphere in all soil treatments, showing that Cd uptake is controlled by diffusion. The flux of Cd from soil to the DGT, with direct contact between the soil and the binding gel, was unaffected by liming whereas it decreased by factor 3 for Zn, closely mimicking the contrasting effects of liming on Cd and Zn bioavailability. This evidence, combined with additional flux data of freshly spiked Cd and Zn isotopes in soil and with modelling, suggests that the diffusive transport of Cd in unsaturated soil is more strongly controlled by the labile adsorbed metal concentration than by its concentration in solution. This is less the case for Zn because of its inherently slower desorption compared to Cd. ispartof: SCIENCE OF THE TOTAL ENVIRONMENT vol:738 ispartof: location:Netherlands status: published

In recent decades, an increasing number of studies have aimed to shed light on the origin and spread of tuberculosis in past human populations. Here we present the results of a systematic palaeodemographic and palaeopathological survey of the Early Mediaeval population of Gars/Thunau (Lower Austria), which - at this stage - includes 373 individuals recovered at two archaeological sub-sites: a fortified settlement (including a necropolis) at the top of a hill - probably reserved for social and military elites; and a large riverine settlement at the foot of the hill, a so-called 'suburbium', where burials and an area of 'industrial' character were discovered. We recorded a great number of pathological alterations and a variety of 'classical' features of tuberculosis, such as vertebral destructions (Pott's disease) and joint destructions, and other pathological (unspecific) features probably linked with Mycobacterium tuberculosis infection (e.g. new bone formation at the inner surface of the ribs, endocranial alterations in the form of 'pits', and new bone formation at the cranial base). We hypothesize that the two contemporaneous (∼900-1000 AD) populations of Gars/Thunau differed not only in their social affiliation/condition, but also in the type and frequencies of their population-density-related infectious diseases (in particular tuberculosis). Moreover, we investigated the molecular genetic evidence of the causative organism in a few selected immatures exhibiting pathological changes at the inner wall of the cranium and discuss these findings in regard to the macroscopic features observed. Finally, we analysed carbon and nitrogen stable isotopes of both populations and strontium isotope ratios of the hill-top inhabitants in order to reconstruct certain aspects of diet and mobility to test our hypothesis concerning the specific social and/or military character of the site.

Phosphorus is a major limiting factor in plant growth and crop production. Phosphorus solubilisation, uptake by plant roots and efflux lead to complex, dynamic cycling of P in the vicinity of plant roots. However, direct observation of P dynamics in the rhizosphere at relevant spatial scales (sub-mm) is still lacking. Chemical imaging of the dissolved P concentration around Brassica napus roots was accomplished using diffusive gradients in thin films (DGT) coupled with laser-ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). Mathematical simulations served for investigating the capabilities of the chemical imaging technique. We show here, for the first time, localised P release along root axes and at root apices. Our results point at differential P uptake efficiencies of the two investigated B. napus cultivars. This study advances the current understanding of P dynamics in the rhizosphere and thus of plant P nutrition. This technique can serve to unravel the genotypic effects on rhizosphere mobilisation of P and hence assist breeding of highly P efficient crop cultivars.

Quantitative studies of the distribution pattern of metals in plant tissues provide important information on the potential of metal-accumulator plants for remediation and amelioration of contaminated soils. We used laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) as well as staining with dimethylglyoxime (DMG) to investigate the distribution pattern of nickel (Ni) in root cross-sections of the Ni-hyperaccumulator plant Berkheya coddii Rossler. Plants were grown in rhizoboxes containing soil with 125 mg kg −1 Ni. Roots were embedded in resin and cut into sections for LA-ICP-MS analysis. For DMG-staining analysis, fresh root cross-sections were prepared using a microtome. LA-ICP-MS revealed higher Ni concentrations in the cortex (374 ± 66 mg kg −1 ) than in the stele (210 ± 48 mg kg −1 ) of the investigated roots. The distribution pattern agreed well with those found by DMG-staining. Higher concentrations of Ni were found in the stele compared to the cortex of roots of the control plants not exposed to elevated soil Ni using both techniques. Our results indicate that an active uptake or ion selection mechanism exists for B. coddii in the absence of available Ni in the rhizosphere.

A rapid method is reported for the determination of (90)Sr in contaminated soil samples in the vicinity of the Chernobyl Nuclear Power Plant by ICP-DRC-MS. Sample preparation and measurement procedures focus on overcoming the isobaric interference of (90)Zr, which is present in soils at concentrations higher by more than six orders of magnitude than (90)Sr. Zirconium was separated from strontium in two steps to reduce the interference by (90)Zr(+) ions by a factor of more than 10(7): (i) by ion exchange using a Sr-specific resin and (ii) by reaction with oxygen as reaction gas in a dynamic reaction cell (DRC) of a quadrupole ICP-MS. The relative abundance sensitivity of the ICP-MS was studied systematically and the peak tailing originating from (88)Sr on mass 90 u was found to be about 3 x 10(-9). Detection limits of 4 fg g(-1) (0.02 Bq g(-1)) were achieved when measuring Sr solutions containing no Zr. In digested uncontaminated soil samples after matrix separation as well as in a solution of 5 microg g(-1) Sr and 50 ng g(-1) Zr a detection limit of 0.2 pg g(-1) soil (1 Bq g(-1) soil) was determined. (90)Sr concentrations in three soil samples collected in the vicinity of the Chernobyl Nuclear Power Plant were 4.66+/-0.27, 13.48+/-0.68 and 12.9+/-1.5 pg g(-1) corresponding to specific activities of 23.7+/-1.3, 68.6+/-3.5 and 65.6+/-7.8 Bq g(-1), respectively. The ICP-DRC-MS results were compared to the activities measured earlier by radiometry. Although the ICP-DRC-MS is inferior to commonly used radiometric methods with respect to the achievable minimum detectable activity it represents a time- and cost-effective alternative technique for fast monitoring of high-level (90)Sr contamination in environmental or nuclear industrial samples down to activities of about 1 Bq g(-1).

The isotopic compositions of lead and strontium and the total concentration of 11 elements (Rb, Sr, Ca, Ba, Cu, Zn, Mn, Fe, Pb, Cr, Cd) in NH4NO3 extracts (reflecting the mobile, bioavailable fraction) and total digests of soil fractions along a soil depth profile were analyzed using sectorfield ICP-MS. This information allows distinguishing between recent external (atmospheric deposition) and primary geogenic sources. Both isotopic systems indicate a clear difference between the surface composition and the composition of lower geogenic levels within the investigated soil profile. An increase of the 87Sr/86Sr isotope ratio can be observed in the total digest down to a depth of about 120 cm for Sr, whereas Pb shows a stable isotopic composition starting from a depth of about 60 cm. We found increased isotopic ratios of 87Sr/86Sr in the mobile fraction of the topsoil compared to the subsoil and to the total digest in the topsoil. This observation and the increased Sr levels in the mobile fraction of the topsoil are an indicator for recent deposition of Sr along with the dust derived from the paving of the forest roads in the study area. The significant change of the 87Sr/86Sr ratios in the total digest at 120 cm depth can be related to a variation in the lithology of this layer, which was confirmed by a concomitant change of the conventionally applied Ti/Zr ratio. This lithogenic inhomogeneity was not apparent from the fairly homogenous distribution of total Sr in the soil profile. Similarly, we were able to distinguish the accumulation of anthroponic heavy metal sources and their recent mobilization within the topsoil from long-term leaching of geogenic sources in deeper soil layers.

TlBr single crystals are promising materials as room temperature X- and gamma ray detectors. However, the TlBr detector performance is generally limited by the quality of the initial crystal material. In this work, the chemical aspects of synthesis, purification, and crystal growth are emphasised. The aim of this paper was to develop characterisation methods for TlBr and study the effect of different impurities on the properties of TlBr. Samples of different types were selected for the investigations, viz. melt grown crystals and material precipitated from water solution. One important topic in the research was to study the purification of TlBr crystals by annealing in pure water. In this paper, the materials were characterised by X-ray diffraction, FTIR spectroscopy, I – V measurements and trace element analysis.

LORandite EXperiment (LOREX) plans to measure the time integrated solar neutrino flux of the last few million years via the product of the reaction 205Tl(υe,e−)205Pb in lorandite of the Allchar mine in Macedonia. Utilizing this reaction is only possible if the background of 205Pb produced by the interaction of secondary cosmic ray particles and particles originating from the natural radioactivity within the rock mineral itself is substantially lower than the expected signal from neutrino interactions. Low abundance of cosmic ray induced 205Pb implies good shielding of the mine by the overlying rock. For the assessment of this background fraction it is necessary to acquire information about the past erosion activity at this site. In the present study the erosion rates have been estimated via cosmogenic 26Al produced in situ in quartz of surface rock materials of the Allchar site. Details of the first determinations of in situ produced 26Al with the AMS method at VERA are described, and a rough estimate of the erosion rates at the Allchar site is given.

Laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS) has been used to investigate the elemental variation for tree rings of 20-year-old clonal Norway spruce trees that grew nearby an aluminum smelter. Four years prior to analysis this source of fluoride pollution was shut down and the subsequent variation of the concentration of elements in the tree ring according to their mobility in the tree stem was investigated by means of a LA-ICPMS. The elements Al, Fe, Ca, Ba and Sr showed a significant increase in values after the pollution shutdown. Elements with similar chemical behavior and mobility show similar patterns of distribution. Circular investigations of tree rings show a variation of up to 60% of the elemental concentration depending on the geographical direction following the changing properties (e.g density) of wood. The circular pattern correlate again for elements with similar properties and function. Furthermore, wood which develops in response to unbalanced mechanical pressure, such as wind for example (so called compression wood) shows significant differences in element concentration compared with unstressed wood.

Polycrystalline ZnS films were grown from ZnCl2 and H2S on glass and mica using the atomic layer epitaxy (ALE) technique. Morphological and crystalline changes during the ALE growth of ZnS were studied by AFM and XRD. AFM measurements revealed that substantial agglomeration took place in the beginning of the growth. On glass the nucleation density of ZnS was higher than on mica and consequently the films on glass remained smoother than those on mica. XRD measurements revealed that orientation of the films was stronger on mica than on glass.

Atomic force microscopy was employed to follow the development of Al 2 O 3 films deposited by atomic layer epitaxy (ALE) from AlCl 3 and H 2 O. In contrast to the earlier observations that substantial agglomeration takes place in the beginning of the ALE growth of polycrystalline films, only very small agglomerates were formed during the growth of the amorphous Al 2 O 3 films. Consequently, no pronounced surface roughening took place with increasing film thickness and the resulting films remained much smoother than the polycrystalline films deposited by ALE. Even a 730 nm thick Al 2 O 3 film had a root-mean-square roughness of only 0.7 nm.

The structural development of HfO2 thin films grown from HfCl4 and water onto glass substrates by atomic layer epitaxy at 500 °C was studied with X-ray diffraction, atomic force microscopy and scanning electron microscopy. The films were found to contain two regions of different crystallinity: a thin amorphous starting layer and a subsequent preferentially oriented polycrystalline layer. The films were built up of densely packed grains. Substantial surface roughening occurred along with increasing film thickness. The films were chlorine free as analyzed by Rutherford backscattering spectrometry.

The surface smoothness of TiO2 films grown by atomic layer epitaxy was improved by incorporating thin intermediate Al2O3 layers into them. The elimination of light scattering from the film surface caused a marked increase in the specular transmittance. Optical measurements, atomic force microscopy, scanning electron microscopy and X-ray diffraction were used in examining the relationships between the amount of Al2O3 added and the optical, morphological and structural properties of the films. The mechanism of the surface roughness reduction is discussed.