3D space intersection features extraction from Synthetic Aperture Radar images

The main purpose of this Thesis is to develop new theoretical models in order to extend the capabilities of SAR images space intersection techniques to generate three dimensional information. Furthermore, the study aims at acquiring new knowledge on SAR image interpretation through the three dimensional comprehension of the scene. The proposed methodologies allow to extend the known radargrammetric applications to vector data generation, exploiting SAR images acquired with every possible geometries. The considered geometries are points, circles, cylinders and lines. The study assesses the estimation accuracy of the features in terms of absolute and relative position and dimensions, analyzing the nowadays operational SAR sensors with a special focus on the national COSMO-SkyMed system. The proposed approach is original as it does not require the direct matching between homologous points of different images, which is a necessary step for the classical radargrammetric techniques; points belonging to the same feature, circular or linear, recognized in different images, are matched through specific models in order to estimate the dimensions and the location of the feature itself. This approach is robust with respect to the variation of the viewing angle of the input images and allows to better exploit archive data, acquired with diverse viewing geometries. The obtained results confirm the validity of the proposed theoretical approach and enable important applicative developments, especially in the Defence domain: (i) introducing original three dimensional measurement tools to support visual image interpretation; (ii) performing an advanced modelling of building counting only on SAR images; (iii) exploiting SAR images as a source for geospatial information and data; (iv) producing geospatial reference information, such as Ground Control Point, without any need for survey on the ground

Does Sex Speed Up Evolutionary Rate and Increase Biodiversity?

Most empirical and theoretical studies have shown that sex increases the rate of evolution, although evidence of sex constraining genomic and epigenetic variation and slowing down evolution also exists. Faster rates with sex have been attributed to new gene combinations, removal of deleterious mutations, and adaptation to heterogeneous environments. Slower rates with sex have been attributed to removal of major genetic rearrangements, the cost of finding a mate, vulnerability to predation, and exposure to sexually transmitted diseases. Whether sex speeds or slows evolution, the connection between reproductive mode, the evolutionary rate, and species diversity remains largely unexplored. Here we present a spatially explicit model of ecological and evolutionary dynamics based on DNA sequence change to study the connection between mutation, speciation, and the resulting biodiversity in sexual and asexual populations. We show that faster speciation can decrease the abundance of newly formed species and thus decrease long-term biodiversity. In this way, sex can reduce diversity relative to asexual populations, because it leads to a higher rate of production of new species, but with lower abundances. Our results show that reproductive mode and the mechanisms underlying it can alter the link between mutation, evolutionary rate, speciation and biodiversity and we suggest that a high rate of evolution may not be required to yield high biodiversity

Effects of compression on SAR image interpretability

SAR images relevance for IMINT (IMagery INTelligence) and civil protection applications has increased in the last years, especially regarding the provision of information to decision makers acting in Area of Operations outside the national borders. Therefore, it is necessary to send information, as well as images, to the Area of Operations through Telecommunication satellites. The large data amount of new systems requires both large bandwidth allocation and transmission time, clearly unacceptable for near real-time applications. Image compression could be a suitable solution, but strict image-interpretability limitations request the saving of critical details. This research analyzes the effect of JPEG and wavelet-based compression on interpretability of SAR images provided by COSMO-SkyMed (CSK) system and Sandia National Laboratories. Images were given to a set of military analysts who expressed a subjective judgement on the image quality and used them to carry out actual detection tasks. Both subjective and objective results show that a moderate amount of compression is perfectly acceptable and does not entail measurable losses in the ability to detect targets of interest. The wavelet-based techniques provide superior performance w.r.t. JPEG, as expected, and the use of ROIs further improves the experimental results

Morphea, an unusual side effect of anti-TNF-alpha treatment

[No abstract available

Geological constraints for earthquake faulting studies in the Colfiorito area (central Italy)

On September 26, 1997. at 00.33 h (GMT), a Mw 5.7 earthquake occurred in the axial zone of the Umbria-Marche Apennines of central Italy, in the Colfiorito basin area. At 09.40 h (GMT), a Mw 6.0 earthquake again struck the area within the Colfiorito basin, a major intramontane basin filled with Quaternary continental deposits. The two main shocks, and the associated aftershocks were within a roughly NNW-SSE trending zone of largest damage (Imax 10), in which ground deformation has been observed. Along this trend, Cello et al. (1997a) had mapped a few capable faults, showing transtensional to pure extensional kinematics. Field inspection of the mapped faults, carried out after the main shocks, revealed that some of them were locally reactivated (for lengths of several hundreds metres and surface slip in the range of 2-8 cm) during the September 26, 1997 earthquakes.On September 26, 1997. at 00.33 h (GMT), a Mw 5.7 earthquake occurred in the axial zone of the Umbria-Marche Apennines of central Italy, in the Colfiorito basin area. At 09.40 h (GMT), a Mw 6.0 earthquake again struck the area within the Colfiorito basin, a major intramontane basin filled with Quaternary continental deposits. The two main shocks, and the associated aftershocks were within a roughly NNW-SSE trending zone of largest damage (Imax 10), in which ground deformation has been observed. Along this trend, Cello et al. (1997a) had mapped a few capable faults, showing transtensional to pure extensional kinematics. Field inspection of the mapped faults, carried out after the main shocks, revealed that some of them were locally reactivated (for lengths of several hundreds metres and surface slip in the range of 2-8 cm) during the September 26, 1997 earthquakes

The prognostic value of histology in ulcerative colitis in clinical remission with mesalazine

Background: The aim of the study was to compare the prognostic value of histological and endoscopic activity in patients with ulcerative colitis (UC). Methods: Patients in clinical remission for 1 year under treatment with mesalazine underwent a planned colonoscopy with biopsies. Histological activity was scored using the histological activity index (HAI). Endoscopic activity was scored using the Mayo endoscopic subscore (MES). The clinical course was evaluated measuring relapses needing steroids during a follow up of 3 years. Results: A total of 52 patients were enrolled into the study and followed up for 3 years. At baseline 29 patients (55.77%) had no endoscopic lesions, and 17 patients (32.69%) showed no histological alteration. At 3 years of follow up, overall, 26 patients (50%) were still in steroid-free remission. Using univariate logistic regression analysis, both histological (HAI ⩾ 1) and endoscopic activity (MES ⩾ 1) were significantly associated with outcome, showing, respectively, a relapse risk (odds ratio [OR]) 16.4 times higher than histological remission (HAI 0) (96% confidence interval [CI]: 3.2–84.3) and 6.3 times higher with respect to endoscopic remission (MES 0) (96% CI: 1.9–21.3). After multivariate logistic regression analysis, histological activity was the only factor significantly associated with outcome (OR 10.2; 95% CI: 1.7–59.4). Conclusions: Histological activity has the most powerful prognostic value in predicting the need for steroids in patients with UC in stable clinical remission on mesalazine. It could be considered as a target of therapy in UC