361 research outputs found

    Snowfall series of Turin, 1784-1992: climatological analysis and action on structures

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    The snowfall series of Turin, northwest Italy, is one of the longest available for Europe, with daily observations starting in 1784 and continuous since 1788. The unpublished 207 years data set was carefully obtained from original manuscripts and filed on magnetic media. Mean yearly snowfall amount is 48.9 cm showing a high interannual variability (variation coefficient 79%), with about seven snow days from October through April; the maximum amount was measured in winter 1784–85 (233 cm), followed by 1808–9 with 163 cm. Maximum daily amount was on 4 December 1844 with 64 cm. During the whole period a negative trend is exhibited, increasing in the years following 1890. This pattern is confirmed by the Mann-Kendall test. The change derives from regional climate rather than expansion of the urban area. Return periods of yearly maximum snow loads are calculated in order to contribute to the definition of new values for structural design. A case study of heavy snowfall in January 1987 is examined

    Urban air pollution, climate change and wildfires: The case study of an extended forest fire episode in northern Italy favoured by drought and warm weather conditions

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    The aim of the paper is to describe the spread forest fire event occurred in the Italian Alps in 2017 under extremely drought conditions. In the study the root causes of wildfires and their direct relapses to the air quality of the Western Po valley and the urban centre of Torino have been assessed by means of air pollution measurements (focused to particulate matter with reference samplers and optical particle counters OPCs), meteorological indicators and additional public data. Results show a good correlation among different urban sites and instrument technologies. Concentration data, compared with environmental conditions and historical values describe the clear impact of fires on both local and regional air quality. Indeed, the deferred impact of wildfires on the local wood biomass energy supply chain is briefly outlined. Keywords: Air quality, Biomass, Climate change, Forest fires, Particulate matter, Wildfire

    Statistical analysis of inter-arrival times of rainfall events for Italian Sub-Alpine and Mediterranean areas

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    Abstract. In this work a set of time-series of inter-arrival times of rainfall events, at daily scale, was analysed, with the aim to verify the issue of increasing duration of dry periods. The set consists of 12 time-series recorded at rain gauges in 1926–2005, six of them belong to an Italian Sub-Alpine area (Piedmont) and six to a Mediterranean one (Sicily). In order to overcome the problem related to limited sample size for high values of inter-arrival times, the discrete probability polylog-series distribution was used to fit the empirical data from partial (20 yr) time-series. Moreover, a simple qualitative trend analysis was applied to some high quantiles of inter-arrival times as well as to the average extent of rain clusters. The preliminary analysis seems to confirm the issue of increasing duration of dry periods for both environments, which is limited to the ''cold'' season

    Peritoneal Hydatidosis

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    Secondary peritoneal hydatidosis is caused by spontaneous or iatrogenic rupture of hepatic echinococcal cysts. We describe the case of a 65-year-old Tunisian male patient with previous history of liver hydatidosis who presented to our attention with subocclusive status. Imaging revealed a retrovesical hydatid cyst, adherent to the sigmoid colon. The treatment of choice was surgical removal of the cyst and the sigmoid colon. The patient is now being closely followed up

    Pathophysiology of hypoxemia in mechanically-ventilated patients with COVID-19: A computed tomography study

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    The pathogenesis of hypoxemia during acute respiratory distress syndrome caused by SARS-CoV-2 infection (C-ARDS) is debated. Some observations led to hypothesize ventilation to perfusion mismatch, rather than anatomical shunt, as the main determinant of hypoxemia. In this observational study 24 C-ARDS patients were studied 1 (0–1) days after intubation. Patients underwent a CT scan analysis to estimate anatomical shunt and a clinical test to measure venous admixture at two fractions of inspired oxygen (FiO2), to eliminate oxygen-responsive mechanisms of hypoxemia (ventilation to perfusion mismatch and diffusion limitation). In 10 out of 24 patients venous admixture was higher than anatomical shunt both at clinical (≈50 %) and 100 % FiO2. These patients were ventilated with a higher PEEP and had lower amount of anatomical shunt compared with patients with venous admixture equal/lower than anatomical shunt. In a subset of C-ARDS patients early after endotracheal intubation, hypoxemia might be explained by an abnormally high perfusion of a relatively low anatomical shunt

    Rapamycin does not adversely affect intrahepatic islet engraftment in mice and improves early islet engraftment in humans.

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    Objective: In this study we examined the effect of rapamycin (RAPA), a key component of the immunosuppressive regimen in clinical islet transplantation, on islet engraftment and function in vivo. Methods and results: Diabetic C57BL/6 or BALB/C recipient mice were transplanted with 350 syngeneic islets through the portal vein (PV-Tx; C57BL/6 n = 60; BALB/C n = 22) and treated with once-daily oral RAPA (1 mg/kg) or vehicle. No differences in post-transplant blood glucose concentrations and glucose tolerance were observed between RAPA-and vehicle-treated mice. The impact of RAPA on human islet engraftment was assessed in 10 patients with type 1 diabetes treated with 0.1 mg/kg/day rapamycin before islet transplantation. Compared to non pre-treated islet transplant recipents (n = 12), RAPA pre-treated patients had increased blood RAPA concentrations (p = 0.006) and fasting C-peptide concentrations (p = 0.005) in the two weeks post-transplant. RAPA pre-treatment was associated with a reduction in chemokines CCL2 and CCL3 concentrations pre-transplant (p < 0.01), and a dampened chemokine response (p = 0.005) post-transplant. Concordantly, in vitro RAPA inhibited the secretion of CCL2 and CCL3 by monocytes. Conclusion: Rapamycin does not adversely affect intrahepatic islet engraftment in the mouse, and potentially improves islet engraftment in humans by an anti-inflammatory mechanism

    Applying a probabilistic model of rainfall and snow days occurrence to daily series recorded in NW Italy.

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    Daily precipitation records exist spanning several decades. A valuable amount of climatic information exists in the time-series of interarrival times (IT), defined as the succession of times (number of days) elapsed from a rainy (or snowy) day to the one immediately preceding it.In a previous work, Agnese et al. (2014) have been successfully tested some probabilistic modelling of rain occurrence on Sicily rainfall data; particularly, the better fitting of IT’s observed frequencies was obtained by 3-parameter Lerch-series distribution. In this work thisdistribution is tested on 70 years of 20 precipitation time-series taken in the North-West Italy, both in the plain and in the mountains, up to the 2000 meters altitude. In such Mediterranean climatetwo markedly different behaviours were observed in the dry semester (April to September) and in the wet one (October to March). A better fit was obtained with that simple subdivision of the year, in comparison with the whole year modelling. However, the NW Italy climate is both more similar to the Central Europe one, and it is deeply influenced by the higher peaks of the Alps. Therefore the seasonality of daily precipitation data is much more complicated. Usually spring and fall are the seasons characterized by the higher precipitations, but the convective vs. frontal events also play a role in the IT distributions. In this work, different subdivisions were compared with the whole year fitting. The whole year Lerch distributions successfully fitted the data in a part of the time series, opening the way to interesting climate applications

    Variations of Lys Glacier (Monte Rosa Massif, Italy) from the Little Ice Age to the Present from Historical and Remote Sensing Datasets

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    Alpine glaciers respond to climate imbalance by adjusting their mass and length. In turn, these changes modify the glacial and periglacial environment, leading to increased supraglacial debris cover, the development of glacial lakes and glacier fragmentation. In this research, we investigated the evolution of Lys Glacier (Monte Rosa Group), by studying length, area and volume changes, and evolution of its supraglacial debris cover and proglacial lakes by means of historical sources and high-resolution aerial and satellite orthophotos. Lys Glacier retreated almost continuously, by nearly 2 km, from its maximum Little Ice Age position. More recently, the glacier lost 11.91% of its area between 1975 and 2014 and underwent fragmentation in 2009. Over the same period, glacier fragmentation and tongue stagnation affected the formation and rapid growth of a series of ice-contact lakes and led to a non-linear debris cover evolution. The glacier was also subjected to strong volume losses, with more than 135 m thinning on the ablation tongue from 1991 to 2014. Analysis of the meteorological records (1927–present) from the closest weather station reveals a considerable increase in average annual temperatures by more than 1°C from the mean of 1971–1989 to the mean of 1990–2017
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