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Abstract: 222Rn concentrations have been monitored during the dry season in August 2009 and August 2010, in a reworked alluvial-pyroclastic soil of the Pietramelara Plain, in Southern Italy, with the aim of determining the role of atmospheric factors in producing the quasi-periodic oscillations in soil 222Rn concentrations reported in the literature. In this study we present the results of a detailed analysis and matching of soil 222Rn concentrations, meteorological and solar parameters where the observed oscillations feature a characteristic behavior with second order build-up and depletion limbs, separated by a daily maximum and minimum. All these features are clearly shown to be tied to sunrise and sunset timings and environmental radiative flux regimes. Furthermore, a significant, and previously unreported, second order correlation (r 2 = 0.73) between daily maximum hourly global radiation and the daily range of soil 222Rn concentrations has been detected, allowing estimates of the amplitude of these oscillations to be made from estimated or measured solar radiation data. The correlation has been found to be valid even in the presence of persistent patchy daytime cloudiness. In this case a daytime prolongation of the night-time build up stage and an attenuation or even suppression of daytime depletion is observed (a previously unreported effect). Neither soil cracking, nor precipitation, both suggested in some studies as causative factors for these oscillations, during the dry season appear to be necessary in explaining their occurrence. We also report the results of an artificial shading experiment, conducted in August 2009, that further support this conclusion. As soil 222Rn concentrations during the dry season show a characteristic daily cycle, radon monitoring in soils under these conditions necessarily has to be gauged to the timings of the daily maximum and minimum, as well as to the eventual occurrence of cloudiness and to its related effects, in order to avoid erroneous conclusions. [Copyright &y& Elsevier]

Abstract: 222Rn concentrations have been measured in a well located on the edge of a large Pleistocene–Holocene fan and belonging to the shallow pyroclastic aquifer of the Pietramelara Plain, southern Italy. The aim of this study has been both to characterise the hydrological inputs that determine the influx of 222Rn to the shallow aquifer and to understand the correlations between 222Rn, major ions, physical–chemical parameters and rainfall. Results obtained from the time series indicate that the studied well shows a 222Rn variability that is inconsistent with a mechanism of pure hydrological amplification, such as described in Radon hazard in shallow groundwaters: Amplification and long term variability induced by rainfall (De Francesco et al., 2010a). On the contrary, in this well hydrological amplification appears to be mainly tied to the upwelling of alluvial fan waters, rich in radon, in response to pistoning from recharge in the carbonate substrate. This upwelling of alluvial fan waters occurs during almost the whole period of the annual recharge and is also responsible of the constant increase in 222Rn levels during the autumn–spring period, when both the water table level and weekly rainfall totals drop. Furthermore, a rapid delivery mechanism for 222Rn likely operates through fracture drainage in concomitance with the very first late summer–early autumn rains, when rainfall totals appear largely insufficient to saturate the soil storage capacity. Results obtained from this study appear to be particularly significant in both radon hazard zoning in relation to the shallow aquifer and possibly also for indoor radon, owing to possible shallow aquifer–soil–building exchanges. Moreover, both the spike-like events and the long wave monthly scale background fluctuations detected can also have potential significance in interpreting 222Rn time series data as seismic and/or volcanic precursors. Finally, 222Rn has proved to be an excellent tracer for hydrological inputs to the shallow aquifer when combined with major ions, physical–chemical data and geological and geomorphological controls. [Copyright &y& Elsevier]

Abstract: Indoor radon concentrations have been measured with the α track etch integrated method in public buildings in the town of Pietramelara, north-western Campania, Southern Italy. In particular, our measurements were part of an environmental monitoring program originally aimed at assessing the range of seasonal fluctuations in indoor radon concentrations, at various floors of the studied buildings. However, subsequent analysis of the data and its comparison with the meteorological data recorded in the same period has shown an unexpected pattern at the different floors. In this report we present data suggesting that, besides the well-known medium and longterm periodicity, there could also be a differentiation in major meteorological controlling factors at the different floors of the buildings, a fact that does not appear to have been reported previously. While the lower floors proved to be markedly affected by rainfall, for the upper floors, instead, a different behaviour has been detected, which could possibly be related to global solar radiation. [ABSTRACT FROM AUTHOR]

Abstract: 222Rn concentrations have been determined with a RAD7 radon detector in shallow groundwaters of the Pietramelara Plain, north-western Campania, southern Italy, where pyroclastic deposits, along with recent stream alluvial sediments, come in contact with Mesozoic carbonate reservoirs. The aim of this study has been to study the annual variation of 222Rn concentration in the shallow groundwaters, scarcely considered in the literature and of obvious relevance for radon hazard evaluation. Our results definitely show that 222Rn levels are characterized by a clear annual periodicity, strictly related to rainfall and water table levels, with a pronounced difference between the dry and the wet season. In this last case with concentrations increasing up to two orders of magnitude (up to two times the lower threshold given in the Recommendation 2001/928/EURATOM for public waters). In relation to this, experimental field data will be presented to demonstrate that this variability is due to purely hydrological mechanisms, mainly rinse out and discharge that control leaching efficiency. The detected cycle (Radon Hydrological Amplification Cycle, RHAC) has been generalized for the Mediterranean Tyrrhenian climate. The marked and seasonally persistent amplification in 222Rn levels poses the problem of evaluating the epidemiological risk brought up by this previously not yet reported mechanism. This mechanism, occurring in shallow groundwaters, very likely should strongly influence indoor radon levels via groundwater–soil–building exchange. [Copyright &y& Elsevier]

Abstract: It has been proposed that retinoblastoma is ‘caused’ by two sequential mutations affecting the RB1 gene, but this is a rather outdated view of cancer aetiology that does not take into account a large amount of new acquisitions such as chromosomal and epigenetic alterations. Retinoblastoma remains probably the only cancer in which the rather simplistic ‘two hit’ mutational model is still considered of value, although cancer is known to be associated with genomic and microsatellite instability, defects of the DNA mismatch repair system, alterations of DNA methylation and hystone acethylation/deacethylation, and aneuploidy. Moreover, as it is shown herein, the predictions made by the ‘two hit’ model, are not fulfilled by the clinical and epidemiological data reported so far. Moreover, while the role of mutational events in cancer has been largely questioned in the more recent literature, no serious effort has been done to investigate the role of epigenetic alterations and aneuploidy in retinoblastoma. Through the analysis of the specialised literature and a set of original epidemiological and biological data concerning retinoblastoma, the authors illustrate the evidences arguing against the ‘two hit’ hypothesis and propose that epigenetic factors and aneuploidy play central roles in the disease. [Copyright &y& Elsevier]

Abstract: Recently, mycophenolate mofetil (MMF) has been introduced in the immunosuppressive strategy after kidney transplantation. Recently, the existence of a MMF associated embriopathy has been hypothesized, namely, multiple craniofacial malformations. Only 1 report has described chorioretinal coloboma. We report a case of woman who used MMF throughout pregnancy after kidney transplantation. Her newborn developed coloboma of the right eye associated with an ocular cyst without any other malformation. The other drugs used by our patient are not considered teratogenic. Therefore, it seems reasonable to conclude a causal relationship between MMF and the malformation observed in this newborn. [Copyright &y& Elsevier]