Multiresolution Detection of Persistent Scatterers: A Performance Comparison Between Multilook GLRT and CAESAR

Persistent scatterers (PS) interferometry tools are extensively used for the monitoring of slow, long-term ground deformation. High spatial resolution is typically required in urban areas to cope with the variability of the signal, whereas in rural regions, multilook shall be implemented to improve the coverage of monitored areas. Along this line, SqueeSAR and later Component extrAction and sElection SAR (CAESAR) were introduced for the monitoring of both persistent and (decorrelating) distributed scatterers (DS). Multilook generalized likelihood ratio test (MGLRT) is a detector derived in the context of tomographic SAR processing that has been investigated for a fixed multilook degree. In this work, we address MGLRT and CAESAR in the multiresolution context characterized by a spatially variable multilook degree. We compare the two schemes for the multiresolution selection of PS and DS, highlighting the pros and cons of each scheme, particularly the peculiarities of CAESAR that have important implications at the implementation stage. A performance analysis of both detectors in case of model mismatch is also addressed. Experiments carried out with data acquired by the COSMO-SkyMed constellation support both the theoretical argumentation and the results achieved by resorting to Monte Carlo simulations

Colistin Resistance Onset Strategies and Genomic Mosaicism in Clinical Acinetobacter baumannii Lineages

Abstract: The treatment of multidrug-resistant Gram-negative infections is based on colistin. As result, COL-resistance (COL-R) can develop and spread. In Acinetobacter baumannii, a crucial step is to understand COL-R onset and stability, still far to be elucidated. COL-R phenotypic stability, onset modalities, and phylogenomics were investigated in a clinical A. baumannii sample showing a COL resistant (COLR) phenotype at first isolation. COL-R was confirmed by Minimum-InhibitoryConcentrations as well as investigated by Resistance-Induction assays and Population-AnalysisProfiles (PAPs) to determine: (i) stability; (ii) inducibility; (iii) heteroresistance. Genomics was performed by Mi-Seq Whole-Genome-Sequencing, Phylogenesis, and Genomic Epidemiology by bioinformatics. COLR A. baumannii were subdivided as follows: (i) 3 A. baumannii with stable and high COL MICs defining the “homogeneous-resistant” onset phenotype; (ii) 6 A. baumannii with variable and lower COL MICs displaying a “COL-inducible” onset phenotype responsible for adaptive-resistance or a “subpopulation” onset phenotype responsible for COL-heteroresistance. COL-R stability and onset strategies were not uniquely linked to the amount of LPS and cell envelope charge. Phylogenomics categorized 3 lineages clustering stable and/or unstable COL-R phenotypes with increasing genomic complexity. Likewise, different nsSNP profiling in genes already associated with COL-R marked the stable and/or unstable COL-R phenotypes. Our investigation finds out that A. baumannii can range through unstable or stable COLR phenotypes emerging via different “onset strategies” within phylogenetic lineages displaying increasing genomic mosaicism

Storia e caratteristiche del progetto multicentrico di ricerca "International Self - Report Delinquency Study": il contributo della Criminologia italiana

The present paper reviews the history, the principal characteristics, the recent evolutions and the objectives of the international multi-centric study on juvenile self-report delinquency and victimization called ISRD, and describes the contribution of Italian criminology to the project. The most important international results of the first two waves of the research (ISRD 1 and ISRD2), and the innovations introduced in the planning of the third wave (ISRD3) are also described: The collection of data has been concluded in Italy, but not in all the 35 countries participating to the study

Lista bibliografica

Questa lista bibliografica contiene il secondo aggiornamento della bibliografia della Lisy e deriva dall’assemblaggio da parte della redazione (M. Serdoz ed E. Panfili) dei contributi parziali stilati dai gruppi regionali

Outils de Text Mining pour l'analyse de structures lexicales à éléments variables

The paper aims at showing the advantages of formulating lexical structures with variable elements (LSVE) in terms of symbolic objects (OS). The proposal main consequence is the collapse of the huge information usually present in a text into matrices of complex data. Thus, it is possible to use statistical tools in order to analyse the underlying properties of lexical structures by taking into account their different component distributions. Describing lexical structures with variable elements as symbolic data improves the effort of text mining by putting in a strict relation the knowledge extraction and the statistical analysis steps. The study of such lexical structures is performed by applying a factorial analysis on complex data. An application deals with a very large corpus extracted from Italian newspaper “La Repubblica” during the Nineties. In this study, we analyse the relations among the different components of some lexical structures with variable elements and the temporal evolution of some peculiar semantic traits, related to geographical-historical-political contexts