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Abstract Over the last few years, photocatalytic titanium dioxide coatings have been explored in laboratory conditions to create building materials with self-cleaning and depolluting abilities. Assessing the performances of the photocatalytic surfaces under real conditions may provide basic knowledge to evaluate the potential of real applications of TiO 2 coatings in buildings. In this study, the performance of photocatalytic limestone surfaces obtained through coating with water-dispersed TiO 2 nanoparticles were investigated in an urban environment. Coated and uncoated samples were exposed to an urban site for one year. Before the exposure and periodically afterwards, optical microscopy observations, colour and contact angle measurements were performed on the sample surface. At the end of the exposure period, samples underwent a capillary water absorption test and self-cleaning efficiency was evaluated by a Rhodamine B photodegradation test. Ti and soluble fraction amounts on the sample surfaces were determined by X-ray Fluorescence (XRF) and ion chromatography, respectively. The overall results showed the TiO 2 coating was better able to preserve the surface colour properties early after exposure. After eight months, this effect was lost and the self-cleaning efficiency was reduced to negligible final rates. No clear wettability results and no meaningful capillary behaviour were recorded. A decrease of the photocatalytic activity was due to both partial titania loss and deactivation phenomena. The role of soluble salt ions either adsorbed from the environment or produced by the photocatalytic abatement of pollutants was recognized in the deactivation of the photocatalysts and their accumulation deserves attention for possible stone damage risk implications. Highlights • Performances of a nano-TiO 2 coated limestone in an urban environment are investigated. • Self-cleaning decrease is partially due to the coating loss from the surface. • Coating promotes soluble salt accumulation on the surface leading to NPs deactivation. • Salt ions absorbed from the marine environment strongly contribute to TiO 2 deactivation. • Physical surface properties not always meaningful to follow photocatalyst performances. [ABSTRACT FROM AUTHOR]

Despite significant improvements in the treatment and outcomes of early-stage breast cancer, the quest continues to find biological and molecular markers that would enable earlier diagnosis or better prediction of treatment efficacy and toxicity. Metabolomics—the latest and one of the most exciting of the ‘omic’ sciences—has shown early promise as a non-invasive diagnostic aid in ovarian cancer, and may allow the detection of subtle metabolic changes that could have diagnostic, prognostic or predictive value in breast cancer. Routine monitoring of circulating tumour cells (CTCs) has also been advocated as a novel means of detecting breast cancer progression earlier, and identifying alterations in tumour cells that might signal the need for therapy changes. Ongoing studies should help to answer important questions relating to the use of metabolomics and CTC evaluation as new strategies to monitor cancer progression and identify markers of chemotherapy activity and toxicity. [ABSTRACT FROM PUBLISHER]

The correlation between the optical properties and microstructural parameters of organic semiconductor polymeric thin films is investigated by spectroscopic ellipsometry. Different poly(arylenephenylene)-based films have been deposited by spincoating. The effect of deposition conditions on the microstructure and, hence, optical constants of the polymeric thin films and the dependence of the optical properties and π–π* transition on the structure of the chain backbone are studied. [Copyright &y& Elsevier]