Herein we report a novel study on the reaction mechanism of non-aqueous aluminum/graphite cell chemistry employing 1-ethyl-3-methylimidazolium chloride:aluminum trichloride (EMIMCl:AlCl 3 ) as the electrolyte. This work highlights new insights into the reversibility of the anion intercalation chemistry besides confirming its outstanding cycle life exceeding 2000 cycles, corresponding to more than 5 months of cycling test. The reaction mechanism, involving the intercalation of AlCl 4 À in graphite, has been fully characterized by means of ex situ X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), X-ray absorption near edge structure spectroscopy (XANES) and small-angle X-ray scattering (SAXS), evidencing the accumulation of anionic species into the cathode as the main factor responsible for the slight initial irreversibility of the electrochemical process. Fig. 7 Ex situ SEM images of PG and aluminum electrodes subjected to different numbers of cycles (pristine, and 50 th and 500 th cycles). The electrodes (in the fully discharged state) were taken from Al/EMIMCl:AlCl 3 /PG cells cycled at 25 mA g À1 for the first 5 cycles and 75 mA g À1 for the following cycles (25 C).This journal is

The highest incidence of melanoma in red haired individuals is attributed to the synthesis and phototoxic properties of pheomelanin pigments. Recently, pheomelanin has also been implicated in UV-independent pathways of oxidative stress; however, the underlying mechanisms have remained uncharted. Herein, we disclose the unprecedented property of purified red human hair pheomelanin (RHP) to promote (i) the oxygen-dependent depletion of major cell antioxidants, for example glutathione and NADH; (ii) the autoxidative formation of melanin pigments from their precursors. RHP would thus behave as a unique 'living' polymer and biocatalyst that may grow by simple exposure to monomer building blocks and may trigger autoxidative processes. These results yield new clues as to the origin of the pro-oxidant state in the red hair phenotype, uncover non-enzymatic pathways of melanogenesis, and pave the way to innovative strategies for melanoma prevention.

Hydrophilic interaction liquid chromatography (HILIC) is a popular technique for the separation of polar compounds, which are poorly retained by reversed-phase liquid chromatography. Despite the versatility and the potentiality of this technique, many analysts still feel uncomfortable when approaching it. The HILIC retention mechanism is not completely elucidated and the availability of many different stationary phases may be confusing during method development. Understanding the principles that drive the separation and how they can be influenced by the selection of both stationary phase and chromatographic conditions enhances the range and the quality of possible applications. For this purpose, the review discusses the primary interactions at the basis of HILIC separations and presents an overview of the most common HILIC stationary phases. The effects of the stationary phase type and chromatographic parameters (i.e., organic solvent and salt content, mobile phase pH and column temperature) on each specific interaction are highlighted.

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