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Breast density is a strong risk factor for breast cancer. In this paper, we present an automated approach for breast density segmentation in mammographic images based on a supervised pixel-based classification and using textural and morphological features. The objective of the paper is not only to show the feasibility of an automatic algorithm for breast density segmentation but also to prove its potential application to the study of breast density evolution in longitudinal studies. The database used here contains three complete screening examinations, acquired 2 years apart, of 130 different patients. The approach was validated by comparing manual expert annotations with automatically obtained estimations. Transversal analysis of the breast density analysis of craniocaudal (CC) and mediolateral oblique (MLO) views of both breasts acquired in the same study showed a correlation coefficient of ρ = 0.96 between the mammographic density percentage for left and right breasts, whereas a comparison of both mammographic views showed a correlation of ρ = 0.95. A longitudinal study of breast density confirmed the trend that dense tissue percentage decreases over time, although we noticed that the decrease in the ratio depends on the initial amount of breast density. [ABSTRACT FROM AUTHOR]

The Barcelona harbour is one of the biggest and most important in commercial and passenger traffic in the Mediterranean Sea. In 2003, construction works for the enlargement of the port were carried out with the opening of a new entrance for large boats in the northern area. Following the opening of this new mouth, the redistribution of heavy metals (Hg, Cd, Pb, Cu, Zn, Ni and Cr), As and polychlorinated biphenyls (PCBs) was investigated to discuss their origin and to evaluate the environmental implications. A previous study of the sediments provided a first picture of high levels of heavy metals and PCBs in the innermost harbour (Port Vell). Then, the opening of the northern mouth led to a remarkable decline in the contaminant concentrations and to an improvement of the sediment quality. During the period 2002–2005, the percentage of concentration decreases in Port Vell for Hg, Pb and PCB (from 20% to 34%), for Zn and Cd (from 10% to 15%) and for the remaining metals with values lesser than 10%. This general decline was probably due to a more efficient water flushing between the original and the new northern entrance. Concentrations of target contaminants were also compared against sediment quality guidelines to assess the ecotoxicological significance of sedimentary contaminants on the benthic communities. [ABSTRACT FROM AUTHOR]

Sediments have long been recognised as a sink for many contaminants like polycyclic aromatic hydrocarbons (PAHs) and tributyltin (TBT), which by virtue of their nature can strongly adsorb onto sediments affecting the benthic community inhabiting them. Using geographical information systems, this study reports and combines the results of several already existing studies along Barcelona harbour in order to assess the potential ecological impacts of these contaminants on the benthos of the harbour ecosystem. Chemical analysis indicated low to moderate contents of PAHs and high contents of TBT in sediments in Barcelona harbour. Comparison against existing sediment quality guidelines (SQGs) indicated that acutely toxic effects would not be expected for PAHs but for TBT, which represents a serious environmental threat for the benthic community. Benthos surveys revealed a deterioration of the benthic community throughout the harbour, especially in the inner port. [Copyright &y& Elsevier]