76 research outputs found
Forme di intensificazione e identità degeneri. Strategie identitarie ed esempi di alterità nel De reditu suo di Rutilio Namaziano
This paper focuses on Rutilius Namatianus, praefectus Urbi, who around 417 AD. is forced from Rome to return to his native Gaul, to take care of his possessions. He tells of this journey in De reditu suo, after years of political commitment at the highest levels in the city: during the stops of the journey the author provides large portraits of friends and associates, which he praises virtutes and cursus honorum of. The constant reference to the office of the urban prefecture (or other high government offices) suggests the concern of Rutilius for what makes Rome an excellent place of civilization: temples, roads, aque-ducts, ports, infrastructures that were under direct responsibility of praefectus Urbi. These elements are very significant in the very moment of serious identity crisis in the senatorial class. Rutilius through the portraits of his associates builds the image of a so-cial structure that wants to present itself as the true custodian of the values of the senato-rial class, but not really compact and therefore in need of a renewed identity model. On the other side the invectives and the merciless portraits are served for the "others", the anti-models, who counterbalance this model to be renewed; perhaps the most insidious forms of otherness are the degenerate forms of identical, who - contrary to expectations - deny or subvert the identity model of the senatorial class. Finally, examples of perma-nent liminality are the iuvenis of Gorgona and the shameful lineage of Lepidi, real dys-functional models of identity
Change in tau phosphorylation associated with neurodegeneration in the ME7 model of prion disease
Hyperphosphorylation of the microtubule-associated protein tau is a significant determinant in AD (Alzheimer's disease), where it is associated with disrupted axonal transport and probably causes synaptic dysfunction. Although less well studied, hyperphosphorylation has been observed in prion disease. We have investigated the expression of hyperphosphorylated tau in the hippocampus of mice infected with the ME7 prion agent. In ME7-infected animals, there is a selective loss of CA1 synapse, first discernable at 13 weeks of disease. There is a potential that dysfunctional axonal transport contributes to this synaptopathy. Thus investigating hyperphosphorylated tau that is dysfunctional in AD could illuminate whether and how they are significant in prion disease. We observed no differences in the levels of phosphorylated tau (using MC1, PHF-1 and CP13 antibodies) in detergent-soluble and detergent-insoluble fractions extracted from ME7- and NBH- (normal brain homogenate) treated animals across disease. In contrast, we observed an increase in phospho-tau staining for several epitopes using immunohistochemistry in ME7-infected hippocampal sections. Although the changes were not of the magnitude seen in AD tissue, clear differences for several phospho-tau species were seen in the CA1 and CA3 of ME7-treated animals (pSer(199-202)>pSer(214)>PHF-1 antibody). Temporally, these changes were restricted to animals at 20 weeks and none of the disease-related staining was associated with the axons or dendrites that hold CA1 synapses. These findings suggest that phosphorylation of tau at the epitopes examined does not underpin the early synaptic dysfunction. These data suggest that the changes in tau phosphorylation recorded here and observed by others relate to end-stage prion pathology when early dysfunctions have progressed to overt neuronal loss
Sea-level variability in the Mediterranean Sea from altimetry and tide gauges
Sea-level variability in the Mediterranean Sea was investigated by means of in-situ (tide-gauge) and satellite altimetry data over a period spanning two decades (from 1993 to 2012). The paper details the sea-level variations during this time period retrieved from the two data sets. Mean sea-level (MSL) estimates obtained from tide-gauge data showed root mean square differences (RMSDs) in the order of 40–50 % of the variance of the MSL signal estimated from satellite altimetry data, with a dependency on the number and quality of the in-situ data considered. Considering the individual time-series, the results showed that coastal tide-gauge and satellite sea-level signals are comparable, with RMSDs that range between 2.5 and 5 cm and correlation coefficients up to the order of 0.8. A coherence analysis and power spectra comparison showed that two signals have a very similar energetic content at semi-annual temporal scales and below, while a phase drift was observed at higher frequencies. Positive sea-level linear trends for the analysis period were estimated for both the mean sea-level and the coastal stations. From 1993 to 2012, the mean sea-level trend (2.44 ± 0.5 mm year- 1) was found to be affected by the positive anomalies of 2010 and 2011, which were observed in all the cases analysed and were mainly distributed in the eastern part of the basin. Ensemble empirical mode decomposition showed that these events were related to the processes that have dominant periodicities of ∼ 10 years, and positive residual sea-level trend were generally observed in both data-sets. In terms of mean sea-level trends, a significant positive sea-level trend (> 95 %) in the Mediterranean Sea was found on the basis of at least 15 years of data. © 2016, The Author(s)
Coastal sea responses to atmospheric forcings at two different resolutions
We investigated coastal sea responses to three, multi-day strong wind episodes that occurred in the middle Adriatic during the Target Operational Period (TOP) of the European COastal sea OPerational observing and forecasting system (ECOOP) project. A high-resolution oceanographic model (1 km horizontal, 16 σ vertical layers) based on the modified Princeton Ocean Model (POM) was applied to a highly complex domain located in the coastal area of the eastern Adriatic Sea. The oceanographic model was nested into the Adriatic REGional model (AREG-2) covering the entire Adriatic Sea. Meteorological forcing was prepared by two atmospheric models. The coarser model was the European Centre for Medium-range Weather Forecast model (ECMWF, with horizontal and temporal resolutions of 0.25° and 6 h, respectively), and the finer one was the Aire Limitée Adaptation dynamique Développement InterNational model (ALADIN, with horizontal and temporal resolutions of 8 km and 3 h, respectively, and winds dynamically adapted to a horizontal resolution of 2 km). The results show that small-scale atmospheric features, which arise due to the orographically complex mainland and the number of islands and were not reproduced by the coarser atmospheric model, substantially affected surface currents, mass transports, sea surface temperature (SST) and surface salinity in the coastal area during strong Bora. For strong Sirocco, the atmospheric model's resolution was important for currents on the lee sides of islands. © Author(s) 2011
LIS Training: Rio de la Plata
Agenda and training materials for the Interagency Water Working Group (ISAT) workshop, Building Capacity on Scientifically Robust Tools and Methodologies for IWRM in La Plata Basin: Modeling Framework
LIS Training: Rio de la Plata
Agenda and training materials for the Interagency Water Working Group (ISAT) workshop, Building Capacity on Scientifically Robust Tools and Methodologies for IWRM in La Plata Basin: Modeling Framework
Numerical simulation and decomposition of kinetic energy in the Central Mediterranean: Insight on mesoscale circulation and energy conversion
The spatial and temporal variability of eddy and mean kinetic energy of the Central Mediterranean region has been investigated, from January 2008 to December 2010, by mean of a numerical simulation mainly to quantify the mesoscale dynamics and their relationships with physical forcing. In order to understand the energy redistribution processes, the baroclinic energy conversion has been analysed, suggesting hypotheses about the drivers of the mesoscale activity in this area. The ocean model used is based on the Princeton Ocean Model implemented at 1/32° horizontal resolution. Surface momentum and buoyancy fluxes are interactively computed by mean of standard bulk formulae using predicted model Sea Surface Temperature and atmospheric variables provided by the European Centre for Medium Range Weather Forecast operational analyses. At its lateral boundaries the model is one-way nested within the Mediterranean Forecasting System operational products. The model domain has been subdivided in four sub-regions: Sardinia channel and southern Tyrrhenian Sea, Sicily channel, eastern Tunisian shelf and Libyan Sea. Temporal evolution of eddy and mean kinetic energy has been analysed, on each of the four sub-regions, showing different behaviours. On annual scales and within the first 5 m depth, the eddy kinetic energy represents approximately the 60 % of the total kinetic energy over the whole domain, confirming the strong mesoscale nature of the surface current flows in this area. The analyses show that the model well reproduces the path and the temporal behaviour of the main known sub-basin circulation features. New mesoscale structures have been also identified, from numerical results and direct observations, for the first time as the Pantelleria Vortex and the Medina Gyre. The classical kinetic energy decomposition (eddy and mean) allowed to depict and to quantify the permanent and fluctuating parts of the circulation in the region, and to differentiate the four sub-regions as function of relative and absolute strength of the mesoscale activity. Furthermore the Baroclinic Energy Conversion term shows that in the Sardinia Channel the mesoscale activity, due to baroclinic instabilities, is significantly larger than in the other sub-regions, while a negative sign of the energy conversion, meaning a transfer of energy from the Eddy Kinetic Energy to the Eddy Available Potential Energy, has been recorded only for the surface layers of the Sicily Channel during summer. © Author(s) 2011. CC Attribution 3.0 License
Development of super-ensemble techniques for ocean analyses: The Mediterranean Sea case
This is the author accepted manuscript. The final version is available from the publisher via the DOI in this record.A super-ensemble methodology is proposed to improve the quality of short-term ocean analyses for sea surface temperature (SST) in the Mediterranean Sea. The methodology consists of a multiple linear regression technique applied to a multi-physics multi-model super-ensemble (MMSE) data set. This is a collection of different operational forecasting analyses together with ad hoc simulations, created by modifying selected numerical model parameterizations. A new linear regression algorithm based on empirical orthogonal function filtering techniques is shown to be efficient in preventing overfitting problems, although the best performance is achieved when a simple spatial filter is applied after the linear regression. Our results show that the MMSE methodology improves the ocean analysis SST estimates with respect to the best ensemble member (BEM) and that the performance is dependent on the selection of an unbiased operator and the length of training. The quality of the MMSE data set has the largest impact on the MMSE analysis root mean square error (RMSE) evaluated with respect to observed satellite SST. The MMSE analysis estimates are also affected by training period length, with the longest period leading to the smoothest estimates. Finally, lower RMSE analysis estimates result from the following: a 15-day training period, an overconfident MMSE data set (a subset with the higher-quality ensemble members) and the least-squares algorithm being filtered a posteriori.This work was supported by the University
of Bologna as part of the graduate programme in geophysics and
by the MyOcean2 Project. The CMCC Gemina project funded
J. Pistoia’s studies at the University of Exeter. Publication was
supported from the Italian Ministry of Education, University and
Research under the project RITMARE
Socioeconomic Impact Evaluation for Near Real-Time Flood Detection in the Lower Mekong River Basin
Flood events pose a severe threat to communities in the Lower Mekong River Basin. The combination of population growth, urbanization, and economic development exacerbate the impacts of these events. Flood damage assessments, critical for understanding the effects of flooding on the local population and informing decision-makers about future risks, are frequently used to quantify the economic losses due to storms. Remote sensing systems provide a valuable tool for monitoring flood conditions and assessing their severity more rapidly than traditional post-event evaluations. The frequency and severity of extreme flood events are projected to increase, further highlighting the need for improved flood monitoring and impact analysis. In this study we integrate a socioeconomic damage assessment model with a near real-time flood remote sensing and decision support tool (NASA’s Project Mekong). Direct damages to populations, infrastructure, and land cover are assessed using the 2011 Southeast Asian flood as a case study. Improved land use/land cover and flood depth assessments result in rapid loss estimates throughout the Mekong River Basin. Results suggest that rapid initial estimates of flood impacts can provide valuable information to governments, international agencies, and disaster responders in the wake of extreme flood events
Impacts of representing sea-level rise uncertainty on future flood risks: An example from San Francisco Bay.
Rising sea levels increase the probability of future coastal flooding. Many decision-makers use risk analyses to inform the design of sea-level rise (SLR) adaptation strategies. These analyses are often silent on potentially relevant uncertainties. For example, some previous risk analyses use the expected, best, or large quantile (i.e., 90%) estimate of future SLR. Here, we use a case study to quantify and illustrate how neglecting SLR uncertainties can bias risk projections. Specifically, we focus on the future 100-yr (1% annual exceedance probability) coastal flood height (storm surge including SLR) in the year 2100 in the San Francisco Bay area. We find that accounting for uncertainty in future SLR increases the return level (the height associated with a probability of occurrence) by half a meter from roughly 2.2 to 2.7 m, compared to using the mean sea-level projection. Accounting for this uncertainty also changes the shape of the relationship between the return period (the inverse probability that an event of interest will occur) and the return level. For instance, incorporating uncertainties shortens the return period associated with the 2.2 m return level from a 100-yr to roughly a 7-yr return period (∼15% probability). Additionally, accounting for this uncertainty doubles the area at risk of flooding (the area to be flooded under a certain height; e.g., the 100-yr flood height) in San Francisco. These results indicate that the method of accounting for future SLR can have considerable impacts on the design of flood risk management strategies
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