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Abstract: Thin films can make a useful link between single crystal and supported vanadium oxide. The deposition of vanadium oxide thin films with physical vapour deposition techniques ensures clean and highly controllable synthesis. The resulting material is easily accessed with surface sensitive techniques. On flat TiO2 anatase substrates, XPS–XPD and UPS indicated that the vanadia deposition was epitaxial, and fully oxidised if performed in situ. A step closer to typical industrial catalysts was achieved by sputter deposition onto sub-millimetre inert particles. In addition to surface characterisation, these model particle catalysts allow use in reactors for catalytic testing under relevant process conditions. On both silica and titania supports, sputter deposited vanadia of varying thickness proved to be equally well dispersed. Oxidative dehydrogenation (ODH) activity was higher over vanadia/titania (anatase) than over vanadia/silica, demonstrating the synergetic interaction between anatase and vanadia. Highest activity in alkane ODH was observed for vanadia a few monolayers thick, supported on titania-coated particles. [Copyright &y& Elsevier]

The article discusses developments and applications of three-dimensional elemental imaging by means of synchroton radiation micro X-ray fluorescence (micro-XRF) in environmental chemistry. Synchrotron radiation (SR) sources within electron or positron storage rings have been the most brilliant sources of hard X-rays available for scientists today. It also tackles elemental imaging in environmental toxicology.

Abstract: VAlO(N) oxynitrides are promising novel catalysts for the ammoxidation of propane to acrylonitrile. These catalysts are obtained after nitridation of a VAlO oxide precursor in NH3 or during the reaction in a NH3/C3H8/O2 mixture. The local structure around the vanadium atoms in the oxide precursor and in several catalysts that have been used in catalytic tests is studied by X-ray absorption spectroscopy (XAS). The nitridation in NH3 was followed with in situ XAS. The oxide precursors have tetrahedral co-ordinated vanadium, while after full nitridation octahedrons are found and a small decrease in vanadium oxidation state occurs. The catalysts used in the ammoxidation reaction consist of a mixture of these tetrahedrons and octahedrons. [Copyright &y& Elsevier]

Aim A fair to moderate concordance in grading of the total mesorectal excision ( TME) surgical specimen by local pathologists and a central review panel has been observed in the PROCARE (Project on Cancer of the Rectum) project. The aim of the present study was to evaluate the difference, if any, in the accuracy of predicting the oncological outcome through TME grading by local pathologists or by the review panel. Method The quality of the TME specimen was reviewed for 482 surgical specimens registered on a prospective database between 2006 and 2011. Patients with a Stage IV tumour, with unknown incidence date or without follow-up information were excluded, resulting in a study population of 383 patients. Quality assessment of the specimen was based on three grades including mesorectal resection ( MRR), intramesorectal resection ( IMR) and muscularis propria resection ( MPR). Using univariable Cox regression models, local and review panel histopathological gradings of the quality of TME were assessed as predictors of local recurrence, distant metastasis and disease-free and overall survival. Differences in the predictions between local and review grading were determined. Results Resection planes were concordant in 215 (56.1%) specimens. Downgrading from MRR to MPR was noted in 23 (6.0%). There were no significant differences in the prediction error between the two models; local and central review TME grading predicted the outcome equally well. Conclusion Any difference in grading of the TME specimen between local histopathologists and the review panel had no significant impact on the prediction of oncological outcome for this patient cohort. Grading of the quality of TME as reported by local histopathologists can therefore be used for outcome analysis. Quality control of TME grading is not warranted provided the histopathologist is adequately trained. [ABSTRACT FROM AUTHOR]

Lake sediments contain valuable information about past volcanic and seismic events that have affected the lake catchment, and they provide unique records of the recurrence interval and magnitude of such events. This study uses a multilake and multiproxy analytical approach to obtain reliable and high-resolution records of past natural catastrophes from ~600-yr-old annually laminated (varved) lake sediment sequences extracted from two lakes, Villarrica and Calafquén, in the volcanically and seismically active Chilean Lake District. Using a combination of micro-X-ray fluorescence (μXRF) scanning, microfacies analysis, grain-size analysis, color analysis, and magnetic-susceptibility measurements, we detect and characterize four different types of event deposits (lacustrine turbidites, tephra-fall layers , runoff cryptotephras, and lahar deposits) and produce a revised eruption record for Villarrica Volcano, which is unprecedented in its continuity and temporal resolution. Glass geochemistry and mineralogy also reveal deposits of eruptions from the more remote Carrán-Los Venados volcanic complex, Quetrupillán Volcano, and the Huanquihue Group in the studied lake sediments. Time-series analysis shows 112 eruptions with a volcanic explosivity index (VEI) 2 from Villarrica Volcano in the last ~600 yr, of which at least 22 also produced lahars. This signifi cantly expands our knowledge of the eruptive frequency of the volcano in this time window, compared to the previously known eruptive history from historical records. The last VEI 2 eruption of Villarrica Volcano occurred in 1991. Based on the last ~500 yr, for which we have a complete record from both lakes, we estimate the probability of the occurrence of future eruptions from Villarrica Volcano and statistically demonstrate that the probability of a 22 yr repose period (anno 2013) without VEI 2 eruptions is 1.7%. This new perspective on the recurrence interval of eruptions and historical lahar activity will help improve volcanic hazard assessments for this rapidly expanding tourist region, and it highlights how lake records can be used to signifi cantly improve historical eruption records in areas that were previously uninhabited. [ABSTRACT FROM AUTHOR]

Guidelines recommend surgery for Stage I‐II, chemoradiation for Stage III and systemic therapy for Stage IV non‐small cell lung cancer (NSCLC). However, patient related factors and patient preferences influence treatment decisions. We investigated patterns of care for Belgian NSCLC patients in 2010‐2011, based on population‐based data from the Belgian Cancer Registry and administrative databases. The relationship between patient characteristics, institutional diagnostic volume, type of treatment and survival was investigated. Overall, 20.8% of patients received no oncological treatment. 59% and 22.1% of Stage I‐II patients received primary surgery or (chemo)radiation respectively. 34% of Stage III patients received chemoradiation and 17% of Stage IIIA patients had surgery. 70% of Stage IV patients received chemotherapy or targeted therapy. Moderate variability between centres was observed. For Stage IV, systemic therapy was less frequently used in higher volume centres and 1‐year survival was lower in centres that had ≥ 50 new patients yearly. Although not all NSCLC patients received treatment as ideally recommended by guidelines, these results do not necessarily represent poor quality of care as patient characteristics and preferences need to be taken into account. Treatment options targeted towards patients with co‐morbidity or unfit patients is warranted to improve outcomes of all NSCLC patients. [ABSTRACT FROM AUTHOR]

The ultimate origin of water in the Earth's hydrosphere is in the deep Earth-the mantle. Theory and experiments have shown that although the water storage capacity of olivine-dominated shallow mantle is limited, the Earth's transition zone, at depths between 410 and 660 kilometres, could be a major repository for water, owing to the ability of the higher-pressure polymorphs of olivine-wadsleyite and ringwoodite-to host enough water to comprise up to around 2.5 per cent of their weight. A hydrous transition zone may have a key role in terrestrial magmatism and plate tectonics, yet despite experimental demonstration of the water-bearing capacity of these phases, geophysical probes such as electrical conductivity have provided conflicting results, and the issue of whether the transition zone contains abundant water remains highly controversial. Here we report X-ray diffraction, Raman and infrared spectroscopic data that provide, to our knowledge, the first evidence for the terrestrial occurrence of any higher-pressure polymorph of olivine: we find ringwoodite included in a diamond from Juína, Brazil. The water-rich nature of this inclusion, indicated by infrared absorption, along with the preservation of the ringwoodite, is direct evidence that, at least locally, the transition zone is hydrous, to about 1 weight per cent. The finding also indicates that some kimberlites must have their primary sources in this deep mantle region. [ABSTRACT FROM AUTHOR]

Recent studies have suggested that exposure of the freshwater invertebrate Daphnia magna to dietary Zn may selectively affect reproduction without an associated increase of whole body bioaccumulation of Zn. The aim of the current research was therefore to investigate the hypothesis that dietary Zn toxicity is the result of selective accumulation in tissues that are directly involved in reproduction. Since under field conditions simultaneous exposure to both waterborne and dietary Zn is likely to occur, it was also tested if accumulation and toxicity under combined waterborne and dietary Zn exposure is the result of interactive effects. To this purpose, D. magna was exposed during a 16-day reproduction assay to Zn following a 5 × 2 factorial design, comprising five waterborne concentrations (12, 65, 137, 207, and 281 μg Zn/L) and two dietary Zn levels (49.6 and 495.9 μg Zn/g dry wt.). Tissue-specific Zn distribution was quantified by synchrotron radiation based confocal X-ray fluorescence (XRF). It was observed that the occurrence of reproductive inhibition due to increasing waterborne Zn exposure (from 65 μg/L to 281 μg/L) was accompanied by a relative increase of the Zn burdens which was similar in all tissues considered (i.e., the carapax, eggs, thoracic appendages with gills and the cluster comprising gut epithelium, storage cells and ovaries). In contrast, the impairment of reproduction during dietary Zn exposure was accompanied by a clearly discernible Zn accumulation in the eggs only (at 65 μg/L of waterborne Zn). During simultaneous exposure, bioaccumulation and toxicity were the result of interaction, which implies that the tissue-specific bioaccumulation and toxicity following dietary Zn exposure are dependent on the Zn concentration in the water. Our findings emphasize that (i) effects of dietary Zn exposure should preferably not be investigated in isolation from waterborne Zn exposure, and that (ii) XRF enabled us to provide possible links between tissue-specific bioaccumulation and reproductive effects of Zn. [ABSTRACT FROM AUTHOR]