A Nine-year series of daily oxygen and hydrogen isotopic composition of precipitation at Concordia station, East Antarctica

The atmospheric processes determining the isotopic composition of precipitation on the Antarctic plateau are yet to be fully understood, as well as the post-depositional processes altering the snow pristine isotopic signal. Improving the comprehension of these physical mechanisms is of crucial importance for interpreting the isotopic records from ice cores drilled in the low accumulation area of Antarctica, e.g., the upcoming Beyond EPICA drilling at Little Dome C. Up to now, few records of the isotopic composition of precipitation in Antarctica are available, most of them limited in time or sampling frequency. Here we present a 9-year long δ18O and δD record (2008-2016) of precipitation at Concordia base, East Antarctica. The snow is collected daily on a raised platform (1 m), positioned in the clean area of the station; the precipitation collection is still being carried out each year by the winter over personnel. A significant positive correlation between isotopes in precipitation and 2-m air temperature is observed at both seasonal and interannual scale; the lowest temperature and isotopic values are usually recorded during winters characterized by a strongly positive Southern Annular Mode index. To improve the understanding of the mechanisms governing the isotopic composition of precipitation, we compare the isotopic data of Concordia samples with on-site observations, meteorological data from the Dome C AWS of the University of Wisconsin-Madison, as well as with high-resolution simulation results from the isotope-enabled atmospheric general circulation models ECHAM5-wiso and ECHAM6-wiso, nudged with the ERA-Interim and ERA5 reanalyses respectively

Characterization of the boundary layer at Dome C (East Antarctica) during the OPALE summer campaign

The regional climate model MAR was run for the region of Dome C located on the East Antarctic plateau, during Antarctic summer 2011–2012, in order to refine our understanding of meteorological conditions during the OPALE observation campaign. A very high vertical resolution is set up in the lower troposphere, with a grid spacing of roughly 2 m. Comparisons are made with observed temperatures and winds near the surface and from a 45 m high tower as well as sodar and radiation data. MAR is generally in very good agreement with the observations but sometimes underestimates cloud formation, leading to an underestimation of the simulated downward long-wave radiation. Absorbed short-wave radiation may also be slightly overestimated due to an underestimation of the snow albedo and this influences the surface energy budget and atmospheric turbulence. Nevertheless the model provides sufficiently reliable information that represent key parameters when discussing the representativeness of chemical measurements made nearby the ground surface during field campaigns conducted at the Concordia site located at Dome C (3233 m a.s.l.)

Effectiveness of psychological support to healthcare workers by the occupational health service: a pilot experience

Work-related stress is a significant risk for healthcare workers (HCWs). This study aims aevaluating the effectiveness of an individual psychological support programme for hospital workersIn all, 35 workers participated (n). A control group of 245 workers (7n) was set. Occupationadistress was measured by the General Health Questionnaire, (GHQ-12), the quality of life by the Short Form-36 health survey, (SF-36), and sickness absence was recorded. Costs and benefits of the service were evaluated and the return on investment (ROI) was calculated. The level of distress was significantly reduced in the treated group at the end of the follow-up (p < 0.001). Quality of life had significantly improved (p < 0.003). A 60% reduction of sickness absence days (SADs) following the intervention was recorded. After the treatment, absenteeism in cases was significantly lower than in controls (p < 0.02). The individual improvement of mental health and quality of life was significantly correlated with the number of meetings with the psychologist (p < 0.01 and p < 0.03, respectively)The recovery of direct costs due to reduced sick leave absence was significantly higher than the costs of the programme; ROI was 2.73. The results must be examined with caution, given the very limited number of workers treated; this first study, however, encouraged us to continue the experience

A unified model for BAM function that takes into account type Vc secretion and species differences in BAM composition

Transmembrane proteins in the outer membrane of Gram-negative bacteria are almost exclusively β-barrels. They are inserted into the outer membrane by a conserved and essential protein complex called the BAM (for β-barrel assembly machinery). In this commentary, we summarize current research into the mechanism of this protein complex and how it relates to type V secretion. Type V secretion systems are autotransporters that all contain a β-barrel transmembrane domain inserted by BAM. In type Vc systems, this domain is a homotrimer. We argue that none of the current models are sufficient to explain BAM function particularly regarding type Vc secretion. We also find that current models based on the well-studied model system Escherichia coli mostly ignore the pronounced differences in BAM composition between different bacterial species. We propose a more holistic view on how all OMPs, including autotransporters, are incorporated into the lipid bilayer

Nonni bit: anziani al computer. Processi e pratiche di alfabetizzazione e di socializzazione nella città educativa

L’ VIII Congresso Nazionale della Società Italiana di e-Learning (Reggio Emilia, 14-16 Settembre 2011) si è posto l’obiettivo di provare a definire quali potranno essere gli scenari di evoluzione della applicazione e utilizzo delle tecnologie dell’informazione e della comunicazione ai processi della formazione, dell’ educazione, dell’editoria e dell’informazione. Uno sguardo, un ponte, verso il futuro o, meglio, verso i futuri possibili

The surface layer observed by a high-resolution sodar at DOME C, Antarctica

International audienc