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RESUMENEn el presente trabajo se dan a conocer los resultados de los análisis de espectroscopía infrarroja realizados a dos cuentas de ámbar procedentes de la fase II de la necrópolis de Herrería (Molina de Aragón, Guadalajara), fechada a finales del Bronce Final y precedente inmediato de la primera fase celtibérica de dicho cementerio. Los resultados confirman la procedencia báltica de esta materia prima. Ello la convierte en una nueva evidencia +de la llegada de elementos continentales hasta la Meseta oriental, donde dicho substrato cultural desempeñó un papel importante en la gestación de los posteriores pueblos prerromanos. ABSTRACT This paper shows the results of the analysis done with two amber beads coming of the cemetery of Herrería II (Molina de Aragón, Guadalajara); it is dated in LateBronze Age, preceding the Celtiberian period. The Baltic origin of the raw material has been confirmed by the analysis and this origin provides the evidence that continental cultural influences arrived to the meseta during mentioned period.Palabras clave: Ámbar; Península Ibérica; Siglos X-IX a .C .; Intercambios; Arqueometría .

The exposure to chemical mixtures is a problem of concern in developing countries and it is well known that the kidney is the major target organ for toxic elements. This cross-sectional study aimed to estimate the individual and composite mixture effect of a large number of chemical elements on kidney function in gold-mining and surrounding non-mining populations in northeast Colombia. We measured concentrations of 36 chemical elements in hair as indicators of chronic exposure from 199 adult participants. We estimated the effect of exposure to mixtures of chemical elements on estimated glomerular filtration rate (eGFR) using weighted quantile sum regression (WQS). The WQS index of the mixture was associated with reduced eGFR (Coefficient −2.42; 95%CI: −4.69, −0.16) being Be, Cd, Pb, As, and Mn, the principal contributors of the toxic mixture. Mining activities and Hg concentration were not associated with decreased kidney function. Our results suggest that complex mixtures of chemical elements, mainly heavy metals, act as nephrotoxic in these populations and therefore the analysis of chemical element mixtures is a better approach to identify environmental and occupational chemical risks for kidney damage.

Tin (II) oxide has been proposed as potential anode material in lithium rechargeable batteries. Different methods to obtain such compound have been developed with relative difficulty due to the fact that Sn(II) is easily oxidized to Sn(IV). We have applied a different methodology to synthesize SnO-romarchite by modifying the solvent nature of the controlled precipitation route using acetic acid and not water. Although the formation of Sn(IV) oxide could not be completely avoided, X-ray diffraction analysis confirmed the synthesis of metastable tin(II) oxide as major phase at room temperature. In depth analysis using Popa's model for Rietveld refinement allows to precise that the material corresponds to small and distorted crystallites, very anisotropic in size. SEM technique confirmed the microstructure is build of flower-like agglomerates of ~15 μm, in turn made of plate-like individual grains that remind the crystallite structure anisotropy.