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Hair and bone samples procured from the remains of Tycho Brahe were analysed by several analytical techniques. In segmented hair samples, concentrations of Fe, As, Ag and Au at the tips exceeded values for the contemporary population; however, they decreased towards the hair bulbs, similarly to Hg, indicating that recent exposure that was discontinued ~2 months prior to Brahe's death. Several other elements did not follow this pattern. Analyses of bones revealed signs of long-term exposure to Au, while many other elements were within expected ranges. Histopathological examination of bone sections yielded no signs of severe bone metabolic disorders. [ABSTRACT FROM AUTHOR]

The heel pain is a common trouble. The most frequent etiology is a plantar fasciitis, where the right diagnostic and therapeutic algorithms are still not broadly known. This article presents current opinion for differential diagnosis, diagnostic procedures and therapeutic approach. [ABSTRACT FROM AUTHOR]

Instrumental neutron activation analysis with both relative and k0 standardization was used in four experienced laboratories to determine element mass fractions in single-wall carbon nanotube certified reference material (CRM) SWCNT-1. Results obtained were evaluated using the National Institute of Standards and Technology (NIST) "Type B On Bias" approach and yielded consensus values in agreement with National Research Council Canada (NRCC) certified values for Fe, Co, Ni, and Mo and provided mass fraction values for 13 additional elements, namely, Na, Mg, Al, K, Ca, Ti, V, Cr, Mn, Br, La, W, and Au. In addition, prompt γ neutron activation analysis was employed to determine mass fractions of H, B, Co, Ni, and Mo. Results of this work provide a basis for the establishment of reference values of element mass fractions in CRM SWCNT-1, thus expanding its usability for more accurate characterization and benchmarking of similar nanotechnology materials.

The synthesis of graphene materials is typically carried out by oxidizing graphite to graphite oxide followed by a reduction process. Numerous methods exist for both the oxidation and reduction steps, which causes unpredictable contamination from metallic impurities into the final material. These impurities are known to have considerable impact on the properties of graphene materials. We synthesized several reduced graphene oxides from extremely pure graphite using several popular oxidation and reduction methods and tracked the concentrations of metallic impurities at each stage of synthesis. We show that different combinations of oxidation and reduction introduce varying types as well as amounts of metallic elements into the graphene materials, and their origin can be traced to impurities within the chemical reagents used during synthesis. These metallic impurities are able to alter the graphene materials' electrochemical properties significantly and have wide-reaching implications on the potential applications of graphene materials.

In order to uncover patterns and processes of segregation of co-existing cytotypes, we investigated a zone in the eastern Alps (Austria) where diploid and hexaploid individuals of the alpine herb Senecio carniolicus Willd. (Asteraceae) co-occur. Linking the fine-scale distribution of cytotypes to environmental and spatial factors revealed segregation along an ecological gradient, which was also reflected in the cytotype-associated plant assemblages. Compared to diploids, hexaploids are found in more species-rich and denser communities. This may be due to their better competitive ability and lower tolerance of abiotic stress compared to the diploids. The lack of any intermediate cytotypes suggests the presence of strong reproductive isolation mechanisms, whose nature is, however, elusive.