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A batch of electrolysis cells was developed for tritium in water samples enrichment by at least a factor 10. The cell batch is controlled by a pre-programmable electronic system that interrupts the current through any cell when the planned electrolyte volume is attained. A starting and a final distillation of water samples are carried out before and after the electrolytic enrichment. Both distillations are made to dryness in order to avoid isotopic fractionation. A second electrolysis step allowed the tritium enrichment factor (EFT) to be doubled. The EFT was calculated by means of the deuterium enrichment factor (EFD) that was measured by mass spectrometry. The EFT was also measured by liquid scintillation counting. The calculated and measured EFT values were found in good agreement, especially for samples with significant tritium content. (c) 2006 Elsevier Ltd. All rights reserved.

The internal friction phenomenon in metallic and polymeric shape memory materials is analyzed. The experimental results permit validation of a theoretical model which describes qualitatively the temperature dependence of the internal friction for the investigated materials. Moreover, theoretical model accepts not only evaluations of different states of material (solid state structural transformations as martensite-austenite) but also materials very different as nature (metallic or plastic).

Background Lombardy was the epicenter in Italy of the first wave of COVID-19 pandemic. To face the contagion growth, from March 8 to May 8 2020, a regional law re-designed the hub-and-spoke system for time-dependent diseases to better allocate resources for COVID-19 patients. Methods We report the reorganization of the major hospital in Lombardy during COVID-19 pandemic, including the rearrangement of its ICU beds to face COVID-19 pandemic and fulfill its role as extended hub for time-dependent diseases while preserving transplant activity. To highlight the impact of the emergently planned hub-and-spoke system, all patients admitted to a COVID-19-free ICU hub for trauma, neurosurgical emergencies and stroke during the two-month period were retrospectively collected and compared to 2019 cohort. Regional data on organ procurement was retrieved. Observed-to-expected (OE) in-ICU mortality ratios were computed to test the impact of the pandemic on patients affected by time-dependent diseases. Results Dynamic changes in ICU resource allocation occurred according to local COVID-19 epidemiology/trends of patients referred for time-dependent diseases. The absolute increase of admissions for trauma, neurosurgical emergencies and stroke was roughly two-fold. Patients referred to the hub were older and characterized by more severe conditions. An increase in crude mortality was observed, though OE ratios for in-ICU mortality were not statistically different when comparing 2020 vs. 2019. An increase in local organ procurement was observed, limiting the debacle of regional transplant activity. Conclusions We described the effects of a regional emergently planned hub-and-spoke system for time-dependent diseases settled in the epicenter of COVID-19 pandemic in Italy.