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Drowning is the leading cause of death by accident of everyday life in people under 25 years of age. Xenobiotics are frequently involved in drowning cases but their influence on the diagnosis of fatal drowning has not been studied so far. This preliminary study aimed to assess the influence of an alcohol and/or a drug intoxication on the autopsy signs of drowning, and on the results of diatom analyses in drowning deaths. Twenty-eight autopsy cases of drowning including 19 freshwater drownings, 6 seawater drownings, and 3 brackish water drownings were prospectively included. Toxicological and diatom tests were performed in each case. The influence of alcohol and other xenobiotics on drowning signs and diatom analyses was assessed separately then in combination through a global toxicological participation score (GTPS). Diatom analyses showed positive results in lung tissue in every case. No significant association was found between the degree of intoxication and the diatom concentration in the organs, even after considering freshwater drowning cases only. The vast majority of the traditional autopsy signs of drowning were not significantly affected by the individual toxicological status either, with the exception of lung weight which tended to raise in case of intoxication, probably due to the pulmonary edema and congestion increase. Further research on larger autopsy samples is needed to confirm the results of this exploratory study. [ABSTRACT FROM AUTHOR]

The oxidation of chromium at 300 °C was investigated in situ by ToF -SIMS for three different oxygen pressures ( $$P_{{{\text{O}}_{2} }} = 2.0 \times 10^{ - 7}$$ , 6.0 × 10 and 2.0 × 10 mbar). Sequential exposure to the O isotopic tracer was performed to reveal the governing transport mechanism in the oxide film. The evolution of the oxide thickness was monitored. Volatilization of CrO was evidenced. A model was used to describe the kinetics resulting from the measurements. Both the parabolic and volatilization constants showed a dependence on oxygen partial pressure like $$P_{{{\text{O}}_{2} }}^{ - 1/n}$$ , with n = 1.9 ± 0.1, indicating a defect structure mainly consisting of oxygen vacancies. The re-oxidation in O shows a growth of the oxide layer at the metal/oxide interface, demonstrating an oxidation process governed by anionic transport via oxygen vacancies. The diffusion coefficient of oxygen in the oxide was determined by fitting the ToF -SIMS depth profiles. It is 2.0 × 10 cm s. [ABSTRACT FROM AUTHOR]

Scanning tunneling microscopy was used to study the reactivity of self-organized nanostructured O/Cu(110) surfaces towards H 2 S. We took advantage of the fast and easy nanostructuring process of the O/Cu(110) system to study in detail the reaction mechanisms on three structures having different width of CuO stripes. Detachment of Cu–O chains from CuO stripes occurred in all cases but the formation of S-c(2 ×2) islands was observed only on wider ( >10 nm) CuO stripes. At low exposure, structures were observed at the CuO stripe edge. Linear structures, aligned along the [ 1 1 ¯ 0 ] direction and showing 2 × periodicity, were also observed on copper stripes. The competition between detachment and c(2 × 2) island growth mechanism depends on the H 2 S adsorption rate. At higher pressure, it is shown that the sulfidation only proceeds by sulfur islands growth in wider CuO stripes. These results show that self-organized nanostructures on metal surfaces are powerful tools to study reactions at the nanometer scale and the relationship between local structure and reactivity. [ABSTRACT FROM AUTHOR]

A method for tuning the nanostructures formed by self-organized growth of oxygen on Cu(110) surface is proposed. It is shown that the range of possible nanostructures, consisting in alternating stripes of bare and oxidized copper, can largely be extended by the co-adsorption of sulfur. The classical Marchenko–Vanderbilt model describing the nanostructuration was generalized in order to take into account the change in the surface properties induced by the presence of sulfur. This modified model enabled us to infer the expressions of the periodicity and width of the self-organized stripes as a function of the sulfur and oxygen coverages. [ABSTRACT FROM AUTHOR]