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We hypothesize that the rapid onset of the carbon isotope excursion (CIE) at the Paleocene/Eocene boundary (V55 Ma) may have resulted from the accretion of a significant amount of 12C-enriched carbon from the impact of a V10 km comet, an event that would also trigger greenhouse warming leading to the Paleocene/Eocene thermal maximum and, possibly, thermal dissociation of seafloor methane hydrate. Indirect evidence of an impact is the unusual abundance of magnetic nanoparticles in kaolinite-rich shelf sediments that closely coincide with the onset and nadir of the CIE at three drill sites on the Atlantic Coastal Plain. After considering various alternative mechanisms that could have produced the magnetic nanoparticle assemblage and by analogy with the reported detection of iron-rich nanophase material at the Cretaceous/Tertiary boundary, we suggest that the CIE occurrence was derived from an impact plume condensate. The sudden increase in kaolinite is thus thought to represent the redeposition on the marine shelf of a rapidly weathered impact ejecta dust blanket. Published reports of a small but significant iridium anomaly at or close to the Paleocene/Eocene boundary provide supportive evidence for an impact

The elucidation of early mineralization of bone is of great interest to the medical world. A clearer understanding of the initial bone formation processes can lead to information regarding the treatment and prevention of bone disorders and fractures and the manufacture of prosthetics. We exploited the mineralizing capabilities of bone cell cultures (osteoblast cultures) to monitor the earliest composition changes during mineral formation using Raman spectroscopy. We observed the first mineralization in 8-day-old osteoblasts and identified the mineral species as one that is very similar to that found in fetal bone tissue, a lightly carbonated apatite. Raman spectra show that carbonation, an indicator of bone maturity, appears at the first detectable stage of mineralization in osteoblasts, and increases over time. We also isolated single osteoblasts by growing them on fused-silica microscope slides. Not only did these cells exhibit abnormal growth patterns, but they also expressed a mineral composition different to a carbonated apatite. Raman spectra of this mineral species have spectral characteristics comparable to those of b-tricalcium phosphate.

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Satellite data have been largely used to detect and monitor flooding events. In particular, data acquired by passive radiometers were recognized as the most adequate to this aim, thanks to their suitable trade-off between temporal and spatial resolution. In this work, nine years of data acquired by the Advanced Microwave Scanning Radiometer (AMSR-E) aboard Earth Observing System (EOS) Aqua, have been investigated by means of the Robust Satellite Techniques (RST) approach, implementing a robust indicator of soil moisture variation, the Polarization Ratio Variation Index (PRVI). Such an index has been applied to analyze the flood which hit Pakistan during summer 2010. Preliminary results shown in this study demonstrated the potential of such an index in providing reliable information about the presence of extremely wet soils, especially when low frequency AMSR-E channels are used