Search

In this study, we derive the travel times and angles of arrival of head-wave correlations from ocean ambient noise in a shallow ocean waveguide with a layered seabed using a vertical line array. The up- and down-going head waves from the same sediment interface are correlated, and their travel time differences give the travel times of head-wave correlations. The angles of arrival of head-wave correlations from different interfaces depend on the sound speeds in the water and seabed layers according to Snell’s law. The head-wave correlations from the water-sediment interface are periodic in time, while those from deeper interfaces show a more complicated time arrival structure. Combining the travel times and angles of arrival of head-wave correlations from different interfaces, it is able to invert for all the sound speeds and layer thicknesses in the water and seabed. The simulation with wind noise and a sediment layer over a half-space seabed verifies the inversion performance., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

An increasing number of foreigners was observed in Italy even among chronic dialysis patients. We compared demographic, clinical, treatment characteristics and survival probability between groups of Italian and foreign patients with chronic dialysis in Lazio.We analysed data from the Lazio Dialysis and Transplantation Registry from 2004 to 2012 (4,076 prevalent chronic dialysis patients in 31-12-2012). Among 7,970 incident patients, we evaluated, by country of birth, survival probability by using Kaplan-Meier method and mortality risk, through multiple Cox regression.We observed an increase of foreigners among chronic dialysis patients in Lazio from 2004 (4.4%) up to 2012 (7.6%, test for trend: p0,001). Compared with Italians, foreign patients were younger (53.816.3 vs. 68.713.6) and more frequently: women (42.7% vs. 37.7%), HbsAg-positive (18.1% vs. 13.9%), not vaccinated if HBV susceptible (26.8% vs. 20.9%), late referral (21.6% vs. 12.9%) and suitable for kidney transplantation (21.7% vs. 9.9%). Foreigners compared with Italians had higher survival probability at 1 year (91.9% vs. 84.7%) and 5 years (74,6% vs. 51,5%) after chronic dialysis has been started. We observed a lower mortality risk (HR=0.71;IC95%:0.58-0.87) among foreign patients even after adjustment for many potential confounding factors. Our findings suggest that health status and treatment of end stage renal disease, including access to kidney transplantation, were similar between groups of Italian and foreign patients in Lazio. Observed differences in patients' characteristics were probably attributable to younger age of foreigners. However, further analyses are needed to fully explain higher survival probability in chronic dialysis among foreigners compared with Italians.

The idea to couple the Treatment Planning System (TPS) to the information on the real boron distribution in the patient is the main added value of the new methodology set-up at DIMNP of University of Pisa, in collaboration with the JRC of Petten (NL). The methodology has been implemented in the new TPS, called BDTPS (Boron Distribution Treatment Planning System), which takes into account the actual boron distribution in the patient brain, while the standard TPS assumes a uniform boron distribution, absolutely far from the reality. Nowadays, Positron Emission Tomography (PET) is able to provide this in vivo information. The new TPS, based on the Monte Carlo technique, has been validated comparing the main BNCT parameters (thermal flux, boron dose, etc.) as measured during the irradiation of a special heterogeneous boron phantom (HEBOM), ad hoc designed, as calculated by the BDTPS and by the standard TPS SERA. An evident SERA overestimation of the thermal neutron flux, as well as the boron dose, has been detected. On the other hand, BDTPS response is in good agreement with the calculation results obtained using a MCNP analytical model. Hopefully, this study is the starting point for future improvements in the TPS research and will be followed by similar works, with the aim to confirm that PET-based TPS methodology represents the next frontier in the BNCT applications.

E’ possibile attribuire un riconoscimento, una legittimazione ed una regolamentazione giuridica all'opera prestata dai privati nell'attività di rigenerazione e riuso di beni di interesse comune? La leva fiscale può essere considerata come strumento per favorire lo sviluppo di queste attività? Alla prima domanda possiamo rispondere che il concetto, oggi in evoluzione, di sussidiarietà orizzontale, sembra essere lo strumento più idoneo per inquadrare giuridicamente le azioni di privati cittadini che volontariamente decidono di prendersi cura di beni comuni ai più diversi livelli (beni immobili o mobili concernenti il patrimonio artistico/culturale o, più in generale, fruibili da una collettività determinata). Per rispondere alla seconda domanda è, invece, necessario chiedersi se esista un rapporto fra sussidiarietà orizzontale e fiscalità e, cioè, se quest’ultima possa essere idoneo strumento di sviluppo della prima. Scopo del presente paper è analizzare sistematicamente queste problematiche.

The interaction of laser light with a semiconductor surface is studied by means of an optical microscope. The surface treatment is shown to affect the nature of the damage. On lapped surfaces the damage is found to consist essentially of a removal of matter from the semiconductor surface, while on etched surfaces it is mainly limited to the occurence of melting. A qualitative explanation of these differences in behavior is given.The interaction of laser light with a semiconductor surface is studied by means of an optical microscope. The surface treatment is shown to affect the nature of the damage. On lapped surfaces the damage is found to consist essentially of a removal of matter from the semiconductor surface, while on etched surfaces it is mainly limited to the occurence of melting. A qualitative explanation of these differences in behavior is given.