1,590 research outputs found
Multitemporal dendrogeomorphological analysis of slope instability in Upper Orcia Valley (Southern Tuscany, Italy)
The Upper Orcia Valley (Southern Tuscany, Italy) is a key site for the
comprehension of denudation processes typically acting in Mediterranean
badlands (calanchi) areas, thanks to the availability of long-lasting
erosion monitoring datasets and the rapidity of erosion processes development.
These features make the area suitable as an open air laboratory
for the study of badlands dynamic and changes in geoheritage due to
erosion (i.e. active geomorphosites).
Decadal multitemporal investigations on the erosion rates and the
geomorphological dynamics of the study area allowed to highlight a decrease
in the average water erosion rates during the last 60 years. More in
detail, a reduction of bare land and, consequently, of erosion processes
effectiveness and a contemporary increasing frequency of mass wasting
events were recorded. These trends can be partly related to the land cover
changes occurred in the study area from the 1950s onwards, which
consist of the significant increase of reforestation practices and important
other forms of human impacts on slopes, mainly land levelling for
agricultural exploitation.
In order to better identify the most significant phases of geomorphological
instability occurred in this area during the last decades, an
integrated approach based on multitemporal geomorphological mapping
and dendrogeomorphology analysis on specimen of Pinus nigra Arn.
was used. In detail, trees colonizing a denudation slope located in the
surrounding of the Radicofani town (Tuscany, Italy) and characterized
by calanchi and shallow mass movements deposits, were analyzed for
the 1985-2012 time period. The analysis of the growth anomaly indexes
and of compression wood allowed to determine a spatio-temporal differentiation
along the slope and respect to an undisturbed reference site.
The negative anomaly index results to be more pronounced in the trees
located on the investigated slope with respect to the ones sampled in
a non-disturbed area. Compression wood characterizes trees on slope
sectors mainly affected by runoff and/or mass movements with a different
persistence. Erosion rates were finally calculated through dendrogeomorphological
analysis on tree roots exposure (0.31-3 cm/y runoff
prevailing; 5.86-27.5 cm/y, mass movements prevailing). Dendrogeomorphological
results are in accordance with those obtained in the investigated
areas with multitemporal photogrammetric and geomorphologic
analyses
Fluvial dynamics and watermills location in Basilicata (Southern Italy)
Watermills (grain mills, waulk mills, olive mills, sawmills and
threshing machines) operated in the Basilicata Region from the Roman
Period until the early decades of the twentieth century, representing an
important feature of waterways that is today almost totally forgotten. Using
documentary sources, ancient maps and field survey it is possible to
catalogue and identify the location of these ancient hydraulic structures.
Watermills were usually placed far enough away from the river to avoid
inundation during floods, and near natural knickpoints or artificial steps
in the river long profile that were created by mill engineers. Mill construction
often had significant impacts on a rivers morphology, because
it was necessary to divert the river discharge towards the mill wheel, to
drive the grain-grinding mechanism. Watermill typological variations
have been examined in relation to variations in river pattern to assess
the ways in which the hydrographic and hydrological settings of the Basilicata
Region have affected mill siting and operation. Most Basilicata
watermills were built with a horizontal water-wheel and a tower. The
characteristics of the tower and the associated hydraulic structures varied
according to the environmental setting. Finally, mill positions define
also the locations on the river system that have already been used
to exploit hydraulic power and thus could be useful for future use in the
micro-hydroelectric secto
The LOFT (Large Observatory for X-ray Timing) background simulations
The Large Observatory For X-ray Timing (LOFT) is an innovative medium-class
mission selected for an assessment phase in the framework of the ESA M3 Cosmic
Vision call. LOFT is intended to answer fundamental questions about the
behaviour of matter in the very strong gravitational and magnetic fields around
compact objects. With an effective area of ~10 m^2 LOFT will be able to measure
very fast variability in the X-ray fluxes and spectra. A good knowledge of the
in-orbit background environment is essential to assess the scientific
performance of the mission and to optimize the instrument design. The two main
contributions to the background are cosmic diffuse X-rays and high energy
cosmic rays; also, albedo emission from the Earth is significant. These
contributions to the background for both the Large Area Detector and the Wide
Field Monitor are discussed, on the basis of extensive Geant-4 simulations of a
simplified instrumental mass model.Comment: Proceedings of SPIE, Vol. 8443, Paper No. 8443-209, 201
The effect of the displacement damage on the Charge Collection Efficiency in Silicon Drift Detectors for the LOFT satellite
The technology of Silicon Drift Detectors (SDDs) has been selected for the
two instruments aboard the Large Observatory For X-ray Timing (LOFT) space
mission. LOFT underwent a three year long assessment phase as candidate for the
M3 launch opportunity within the "Cosmic Vision 2015 -- 2025" long-term science
plan of the European Space Agency. During the LOFT assessment phase, we studied
the displacement damage produced in the SDDs by the protons trapped in the
Earth's magnetosphere. In a previous paper we discussed the effects of the Non
Ionising Energy Losses from protons on the SDD leakage current. In this paper
we report the measurement of the variation of Charge Collection Efficiency
produced by displacement damage caused by protons and the comparison with the
expected damage in orbit.Comment: 17 pages, 7 figures. Accepted for publication by Journal of
Instrumentatio
Anthropogenic modifications to the drainage network of Rome (Italy). The case study of the Aqua Mariana
Rome is characterized by millennia of urbanization. Long lasting geomorphological investigations have allowed the geomorphological description of the city centre and the valorisation of its geomorphological heritage. In this paper the spatial change of the hydrographic network in historical times is illustrated, with some examples showing how deep has been, and still it is, the link between the historical-cultural development and the natural geomorphological and hydrological characteristics of the Roman territory. In particular, the most relevant human interventions on the drainage network, in the southern area of the city centre, have been investigated. Before the land-use modifications of Roman-age, this area was drained by the most important left tributary of the Tiber River within the city walls, the Nodicus River, more recently known as Aqua Mariana. This stream has undergone many anthropogenic modifications and diversions during the centuries, and its original path is known only downstream of the San Giovanni Basilica. According to geomorphological, archaeological and geological evidences, it is possible to hypothesize that the dimension of the pre-urbanization drainage basin, as known and reconstructed in the available literature, should have been until now underestimated
Dendrochronological and geomorphological investigations to assess water erosion and mass wasting processes in the Apennines of Southern Tuscany (Italy)
The Tyrrhenian side of the Central Apennines is located in a lively geological context, in which uplift/denudation dynamics played a key role in landscape evolution. Intense water erosion and gravitational processes led to the development of spectacular badlands on the widespread clayey hillslopes. The Crete d'Arbia badlands (as part of the Crete Senesi of Southern Tuscany) represent one of the most beautiful examples of these landforms developed on Pliocene clays. On the other hand, these rapidly evolving landforms endanger the artistic heritage of the area, as with the Monte Oliveto Maggiore Abbey that was constructed on the top of a badland hillslope and confers additional value to the landscape.In the perspective of monitoring and reconstructing some significant phases of the relief evolution of this area an integrated approach has been used, which is based on dendrogeomorphology and geomorphological monitoring techniques. In particular, the correspondence between the data from dendrogeomorphological indicators and the measured denudation rates on badland hillslopes was tested. The sampling for dendrogeomorphological analysis has been performed in two stages on 45 trees of the Pinus pinea L. species, on hillslopes affected by soil creep and shallow landslides, in order to identify annual ring growth anomalies, compression wood and roots exposure. Trees' local behaviour is not homogeneous but some common trends have been detected on the basis of the anomaly index and compression wood. Since 1993 several monitoring stations at badland denudation "hot spots" have been equipped with erosion pins; quantitative data from monitoring stations, compared to pluviometric series, indicated critical phases of denudation that were supported by dendrochronological data. The integrated approach between dendrogeomorphology and geomorphological monitoring techniques allowed calibration of both tools in order to extend the analysis in the period preceding the field measurements. This kind of approach, capable of implementation in many contexts, could be particularly helpful in order to forecast the relief evolutionary trend
Interleukin-2 inhalation therapy in renal cell cancer: a case report and review of the literature
Renal cell carcinoma (RCC) is the most common malignancy of the kidney. One third of RCC presents metastatic disease at the time of diagnosis, usually leading to a fatal outcome. Small response rates were seen with most cytotoxic agents including gemcitabine and vinorelbine, whereas systemic therapy with high doses of interleukin 2 (IL-2) has been shown to provide durable complete remissions. However, in consideration of its severe toxicity, IL-2 immunotherapy is restricted to selected patients. Aerosol IL-2 has been introduced as an alternative therapy in cancer patients. However, only very few data are available on its use in patients with pulmonary metastatic RCC. This paper briefly summarizes current clinical experience with the use of inhaled IL-2 therapy, either as a single therapy or in combination with other treatments. In addition, we report on a male patient with pulmonary metastasized RCC who achieved a durable complete response to combined gemcitabine/vinorelbine and interleukin-2 inhalation therapy
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