71 research outputs found

    NEAAL 2030: per un impegno permanente nell’Educazione degli adulti. Formatori e learner tra accessibilità, responsabilità e resilienza

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    La nuova Agenda per l’apprendimento degli adulti (NEEAL 2030) definisce le priorità per le azioni e le politiche formative future, stabilendo a fondamento quattro pilastri: inclusione, sostenibilità, giustizia, resilienza. Nonostante le potenzialità innovative enunciate, il documento rivela aspetti di criticità su cui ù necessario proporre una riflessione pedagogicamente orientata per dar vita ad una viva cultura dell’apprendimento permanente, capace di generare un approccio globale e personalizzato all’apprendimento adulto

    Modeling the transport of Saharan dust toward the Mediterranean region: an important issue for its ecological implications

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    Airborne particulate matter (PM) is presently an environmental problem of primary concern, whose role in air quality, climatic and ecological issues is well recognized, though still a matter of extensive investigations (Intergovernmental Panel on Climate Change, 2007).It is of great scientific interest to detect sources of atmospheric particulate matter and quantify their influence on the global and local scales. Unfortunately, emissions are usually not directly available, while PM concentration time series are experimentally accessible, so that the problem often consists in "inverting" these data to determine the region of influence that caused the measured concentration. In this paper we are concerned with an alternative approach to inverse modeling based on backward trajectory analysis (BTA); this approach has the potential to overcome some limitations associated with traditional BTA.We apply this method to the analysis of PM time series from the Monte Cimone observatory, hereafter MCT, a high altitude station on the top of the Italian Northern Apennines, with the aim of estimate the contribution of Saharan dust transport on PM concentration levels registered in the Mediterranean region

    Seasonal variation of size-resolved aerosol fluxes in a Peri-urban deciduous broadleaved forest

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    Eddy covariance measurements of aerosol fluxes were performed above an oak-hornbeam forest in the Po Plain (Northern Italy), from February to May and from September to December 2019. Measurements aimed at assessing the influence of forest phenology and leaf presence/absence on the seasonal evolution of size-segregated aerosol fluxes. The size-resolved aerosol concentration in the range 0.006-10 ÎŒm was sampled with a 14-stage impactor (ELPI+, Dekati, FI), and the filters exposed in May were subjected to chemical analysis. Over the whole sampling period, the forest removed from the atmosphere an average of 3.12 mg of aerosol m−2 d−1. The direction and the intensity of the aerosol fluxes were not constant through the year, as a strong seasonal and size-dependent variability emerged. In particular, leaf-presence drove a net deposition of the accumulation mode aerosol (100 nm< particle diameter Dp<1000 nm) and an emission of the Aitken (10 nm< Dp<100 nm) and coarse mode (Dp>1000 nm) aerosols. On the contrary, in absence of leaves all the sub-micrometer aerosol size-classes showed net daily upward fluxes, while coarse mode aerosol fluxes were prevalently downward. Monthly averages of deposition velocities of Aitken and accumulation mode aerosols correlated with the Leaf Area Index (LAI) seasonal trend, thus indicating an important role of the amount of the leaf surface area on the deposition and emission of these size-classes. Furthermore, an influence of the stomatic activity was suggested for the Aitken mode aerosol, since its deposition velocity followed the same diel course of the stomatal conductance to water. The analysis of the influence of meteorological parameters on aerosol deposition velocities highlighted that dynamic and convective turbulence (described by friction velocity, u* and Deardorff velocity, w*) enhanced the vertical aerosol exchanges, both upward and downward, while the approaching of condensing conditions reduced the flux intensities

    delta C-13 signatures of organic aerosols:Measurement method evaluation and application in a source study

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    Analysis of the stable carbon isotope 13C in organic carbon (OC) can give insight into sources and atmospheric processing of carbonaceous aerosols, provided the 13C source signatures are known. However, only few data on 13C signatures of OC emitted by common sources of carbonaceous aerosol are available in Europe. We present and evaluate an improved version of a measurement method to obtain ή13C signatures on organic aerosols desorbed from filter samples at three different desorption temperatures (200 °C, 350 °C and 650 °C) and apply it in a source study. With our calibration approach, the reproducibility of a L-Valine reference material desorbed at a single temperature step of 650 °C shows a standard deviation of 0.19‰ over a period of more than one year. The average ή13C value for this reference material over 248 measurements is −24.10‰, which shows only a slight bias to the nominal value of −24.03‰. Repeated analysis of ambient filter samples desorbed at three temperature steps show typical standard deviations of about 0.3‰ for all temperature steps (200 °C, 350 °C and 650 °C). Isotopic fractionation due to partial thermal desorption during the individual temperature steps was tested on single compound reference materials. It showed significant isotopic fractionation only at temperature steps, in which a very minor fraction of the compound was desorbed. Possible isotope effects caused by charring of organic material were investigated and found to be not significant. The thermal desorption method was applied to various source filter samples from the region of Naples, Italy. We analyzed two different biomass burning sources, exhaust from a city bus and traffic emissions collected in a tunnel and compared these to ambient filter samples from the same region. ή13C signatures of the total OC show values in a narrow range of about −28‰ to −26‰ for all sources, which does not allow a source apportionment only based on 13C. Nevertheless, the results add information to a source inventory of ή13C, where information of 13C in organic aerosol from specific emission sources are rare. City bus emissions show little variation of ή13C over the temperature steps, whereas biomass burning aerosol is enriched in 13C for OC desorbed at 650 °C. For PM10 samples in the urban tunnel an enrichment in ή13C at the 650 °C temperature steps was observed, which is likely caused by the contribution of carbonate carbon to the carbonaceous material desorbed at this temperature step

    Unprecedented use of silver(I) N-heterocyclic carbene complexes for the catalytic preparation of 1,2-bis(boronate) esters

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    Catalytic diboration of internal and terminal alkenes with Ag(I) N-heterocyclic carbene complexes leads to 1,2-bis(boronate) esters as single intermediates, that can be oxidised towards the corresponding diols.Sanau Torrecilla, Mercedes, [email protected]

    Aurantoside J: a New Tetramic Acid Glycoside from Theonella swinhoei. Insights into the Antifungal Potential of Aurantosides

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    The chemical investigation of an Indonesian specimen of Theonella swinhoei afforded four aurantosides, one of which, aurantoside J (5), is a new compound. The structure of this metabolite, exhibiting the unprecedented N-α-glycosidic linkage between the pentose and the tetramate units, has been determined through detailed spectroscopic analysis. The four obtained aurantosides have been tested against five fungal strains (four Candida and one Fusarium) responsible of invasive infections in immuno-compromised patients. The non-cytotoxic aurantoside I (4) was the single compound to show an excellent potency against all the tested strains, thus providing valuable insights about the antifungal potential of this class of compounds and the structure-activity relationships

    A New Orbiting Deployable System for Small Satellite Observations for Ecology and Earth Observation

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    In this paper, we present several study cases focused on marine, oceanographic, and atmospheric environments, which would greatly benefit from the use of a deployable system for small satellite observations. As opposed to the large standard ones, small satellites have become an effective and affordable alternative access to space, owing to their lower costs, innovative design and technology, and higher revisiting times, when launched in a constellation configuration. One of the biggest challenges is created by the small satellite instrumentation working in the visible (VIS), infrared (IR), and microwave (MW) spectral ranges, for which the resolution of the acquired data depends on the physical dimension of the telescope and the antenna collecting the signal. In this respect, a deployable payload, fitting the limited size and mass imposed by the small satellite architecture, once unfolded in space, can reach performances similar to those of larger satellites. In this study, we show how ecology and Earth Observations can benefit from data acquired by small satellites, and how they can be further improved thanks to deployable payloads. We focus on DORA—Deployable Optics for Remote sensing Applications—in the VIS to TIR spectral range, and on a planned application in the MW spectral range, and we carry out a radiometric analysis to verify its performances for Earth Observation studies

    Impact of circulating tumor DNA mutant allele fraction on prognosis in RAS‐mutant metastatic colorectal cancer

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    Metastatic colorectal cancer; RAS analysis; Prognostic biomarkerCĂĄncer colorrectal en metĂĄstasis; AnĂĄlisis RAS; Biomarcador como pronĂłsticoCĂ ncer colorectal en metĂ stasi; AnĂ lisi RAS; Biomarcador com a pronĂČsticDespite major advances in the treatment of metastatic colorectal cancer (mCRC), the survival rate remains very poor. This study aims at exploring the prognostic value of RAS‐mutant allele fraction (MAF) in plasma in mCRC. Forty‐seven plasma samples from 37 RAS‐mutated patients with nonresectable metastases were tested for RAS in circulating tumor DNA using BEAMing before first‐ and/or second‐line treatment. RAS MAF was correlated with several clinical parameters (number of metastatic sites, hepatic volume, carcinoembryonic antigen, CA19‐9 levels, primary site location, and treatment line) and clinical outcome [progression‐free survival (PFS) and overall survival (OS)]. An independent cohort of 32 patients from the CAPRI‐GOIM trial was assessed for clinical outcome based on plasma baseline MAF. RAS MAF analysis at baseline revealed a significant correlation with longer OS [Hazard ratios (HR) = 3.514; P = 0.00066]. Patients with lower MAF also showed a tendency to longer PFS, although not statistically significant. Multivariate analysis showed RAS MAFs as an independent prognostic factor in both OS (HR = 2.73; P = 0.006) and first‐line PFS (HR = 3.74; P = 0.049). Tumor response to treatment in patients with higher MAF was progression disease (P = 0.007). Patients with low MAFs at baseline in the CAPRI‐GOIM group also showed better OS [HR = 3.84; 95% confidence intervals (CI) 1.5–9.6; P = 0.004] and better PFS (HR = 2.5; 95% CI: 1.07–5.62; P = 0.033). This minimally invasive test may help in adding an independent factor to better estimate outcomes before initiating treatment. Further prospective studies using MAF as a stratification factor could further validate its utility in clinical practice.This work was supported partially by the Instituto de Salud Carlos III (Ministerio de Economia y Competitividad) and `Fondo Europeo de Desarrollo Regional (FEDER), una manera de hacer Europa' grants [FIS PI12-01589 to RS] and RETICC Cancer
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