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Factors affecting forest dynamics in the Iberian Peninsula from 1987 to 2012. The role of topography and drought.
No full textIn southern Europe, climate trends are expected to be characterized by an increase in temperatures and less water availability. Analyzing the role of structural factors and the influence of a changing climate provides insights into the evolution of forest ecosystems in regions with similar environmental conditions. The Mediterranean fringe of the Iberian Peninsula is of particular interest due to its diverse topo climatic conditions and the increase in drought episodes during the last decades. This work studies forest dynamics in large areas of this geographical region by analyzing nine forest transitions. Vegetation covers were classified from three Landsat scenes for the period 1987-2012, and sub-periods 1987-2002 and 2002-2012. Conditions were described by topography derived variables, human factors and drought-occurrence variables. Boosted regression trees were used to identify the most important variables and describe the relationships between the forest dynamics and key factors. Variables such as solar radiation, topographic wetness index and tolerance to drought have been shown to be key factors in forest succession and when comparisons are made between vegetation groups. Main findings: The transition rate to Mediterranean and sub-Mediterranean broadleaf forests has increased during the analyzed period, while the transition rate to coniferous forests has decreased; Transitions to Mediterranean and sub-Mediterranean broadleaf forests are positively associated with drought occurrence while transitions to conifers are negatively affected by drought; Transitions from shrublands to forest stages are more vulnerable to factors controlling water availability; Important interactions between topography derived variables and drought have been found. The study provides robust evidence that drought occurrence plays an important role in the decline of conifers and the expansion of broadleaves, which could become the dominant species in many areas of the Mediterranean if climate model forecasts are met
Radiometric Correction of Simultaneously Acquired Landsat-7/Landsat-8 and Sentinel-2A Imagery Using Pseudoinvariant Areas (PIA): Contributing to the Landsat Time Series Legacy
No full textThe use of Pseudoinvariant Areas (PIA) makes it possible to carry out a reasonably robust and automatic radiometric correction for long time series of remote sensing imagery, as shown in previous studies for large data sets of Landsat MSS, TM, and ETM+ imagery. In addition, they can be employed to obtain more coherence among remote sensing data from different sensors. The present work validates the use of PIA for the radiometric correction of pairs of images acquired almost simultaneously (Landsat-7 (ETM+) or Landsat-8 (OLI) and Sentinel-2A (MSI)). Four pairs of images from a region in SW Spain, corresponding to four different dates, together with field spectroradiometry measurements collected at the time of satellite overpass were used to evaluate a PIA-based radiometric correction. The results show a high coherence between sensors (r2 = 0.964) and excellent correlations to in-situ data for the MiraMon implementation (r2 > 0.9). Other methodological alternatives, ATCOR3 (ETM+, OLI, MSI), SAC-QGIS (ETM+, OLI, MSI), 6S-LEDAPS (ETM+), 6S-LaSRC (OLI), and Sen2Cor-SNAP (MSI), were also evaluated. Almost all of them, except for SAC-QGIS, provided similar results to the proposed PIA-based approach. Moreover, as the PIA-based approach can be applied to almost any image (even to images lacking of extra atmospheric information), it can also be used to solve the robust integration of data from new platforms, such as Landsat-8 or Sentinel-2, to enrich global data acquired since 1972 in the Landsat program. It thus contributes to the program\u27s continuity, a goal of great interest for the environmental, scientific, and technical community
A generalized definition of reactivity for ecological systems and the problem of transient species dynamics
No full text1. Perturbations to an ecosystem\u27s steady state can trigger transient responses of great ecological relevance. Asymptotic stability determines whether a generic perturbation will fade out in the long run, but falls short of characterizing the dynamics immediately after an equilibrium has been perturbed. Reactivity, traditionally defined as the maximum instantaneous growth rate of small perturbations to a stable steady state, is a simple yet powerful measure of the short- term instability of a system as a whole. In many ecological applications, however, it could be important to focus on the reactivity properties of just some specific, problem-dependent state variables, such as the abundance of a focal species engaged in interspecific competition, either predators or preys in a trophic community, or infectious individuals in disease transmission. 2. We propose a generalized definition of reactivity (g-reactivity) that allows to evaluate the dif- ferential contribution of the state space components to the transient behavior of an ecological system following a perturbation. Our definition is based on the dynamic analysis of a system output, corresponding to an ecologically-motivated linear transformation of the relevant state variables. We demonstrate that the g-reactivity properties of an equilibrium are determined by the dominant eigenvalue of an Hermitian matrix that can be easily obtained from the Jacobian associated with the equilibrium and the system output transformation. 3. As a testbed for our methodological framework, we analyze the g-reactivity properties of simple spatially-implicit metapopulation models of some prototypical ecological interactions, namely competition, predation and transmission of an infectious disease. We identify con- ditions for the temporary coexistence of an invader with a (possibly competitively superior) resident species, for transitory invasion of either prey or predator in otherwise predator- or prey-dominated ecosystems, and for transient epidemic outbreaks. 4. Through suitable examples, we show that characterizing the transient dynamics associated with an ecosystem\u27s steady state can be, in some cases, as important as determining its asymp- totic behavior, from both theoretical and management perspective. Because g-reactivity anal- ysis can be performed for systems of any complexity in a relatively straightforward way, we conclude that it may represent a useful addition to the toolbox of quantitative ecologists
PBZ (Pini, Bonuccelli, Zappella): Scala italiana per la valutazione clinica della Sindrome di Rett
No full text,La Sindrome di Rett ? una malattia genetica del neurosviluppo, che interessa quasi esclusivamente le femmine: la sua variabilit? ? ampia, dal punto di vista sia clinico che genetico. le classificazioni internazionali (Neul et al. 2010)riconoscono forme classiche e varianti con alterazione del gene MECP2 (questo vale per la forma classica e per la variante di Zappella) e altre con alterazioni genetiche differenti: forma congenita (gene FOXG1) e a esordio precoce dell\u27epilessia (CDKL5) che presentano esordio, andamento e gravit? differenti. La PBZ ? una scala di valutazione realizzata per testare la gravit? nella Sindrome di Rett e nelle sue varianti. La scala ? sensibile non solo nel registrare cambiamenti clinici anche minimi della sintomatologia in corso di nuova terapia, di programmi riabilitativi e di arricchimento ambientale ma anche nell\u27indicare la gravit? dei singoli gruppi clinici e genetici. Rispetto alle altre scale utilizzate fino ad oggi come l\u27ISS (Kerr et al. 2001) risulta particolarmente utile per la sua sensibilit? a cogliere modificazioni sintomatologiche nel campo osservazionale come nei trial clinici e farmacologici, nel corso di programmi riabilitativi di arricchimento ambiental
Technical report on the methodology used for the analysis of websites
No full textNew Psychoactive Substances (NPS) are drugs that lay in a grey area of legislation, since they are not internationally and officially banned, possibly leading to their not prosecutable trade. The exacerbation of the phenomenon is that NPS can be easily sold and bought online. This has also some effects over social media like forums and social networks, that are often used to discuss about new drugs and advertise them. This work introduces the techniques that enable the analysis of data coming from the Web, using scraping techniques and indexing of contents for a fast evaluation of analytics, useful for a broader comprehension of the phenomenon. Here we describe a broad list of tools suitable for scraping activity and illustrate how we collected data from forums and websites
#tweeTag: a web?based annotation tool for Twitter data
No full textThe manual annotation of tweets is an essential task for the training of new algorithms based on those data. Unfortunately, conventional and consolidated automatic annotation systems that already exists are based and trained on documents where text is longer than 140 characters (the maximum length of a tweet) and the grammar is correct. Besides the length, tweets must be treated differently because they have peculiar characteristics, such as the presence of links, abbreviations, hashtags and mentions. To face the challenge of the linguistic annotation of tweets, we have created #tweeTag, a web?tool designed for a specific approach on tweets. The tool is able to annotate tweets in three different ways: (i) global annotation to bring out macro characteristics of the tweet, given context (e.g., if it is related to a certain phenomenon, if it is positive or negative etc.)? (ii) textual annotation to annotate the text of a tweet in order to identify information about the topic or content (e.g., whether describes various types of damage to property and/or people, etc)? (iii) timeline annotation to evaluate the credibility of a specific user through the analysis of its timeline. 1 #tweeTag has been developed in order to make it possible to run multiple annotation campaigns with different purposes in order to meet every need. Results show a usable and effective tool, with great potential for the near future. As this is a web application, #tweeTag could also be implemented as a crowdsourcing system
Rivista Tuttoscuola n. 563: Bologna Children\u27s Book Fair
No full textL\u27articolo illustra la partecipazione al Bologna Children\u27s Book Fair della Ludoteca del Registro .it. In particolare l\u27evento ? stata l\u27ocasione per presnetare alla fiera internazionale dedicata all\u27editoria per bambini l\u27app Internetopoli, dedicata al mondo di Internet
Gestione dei Totem Indoor ed Outdoor dell\u27 Area CNR Pisa
No full textLe odierne tecnologie ICT possono essere usate per far confluire dati di vario tipo all\u27interno di un cloud per poi poter essere essere integrati tra di loro e analizzati. Questi dati sono in grado di fornire informazioni intelligenti agli utilizzatori di qualche servizio ed in questa ottica, l\u27 Area della Ricerca di Pisa si ? dotata di un sistema di Totem Interattivi in grado di fornire indicazioni in modo interattivo. Questo documento vuole dare un\u27idea di base della gestione di questo strumento e delle sue potenzialit?
Methods for the Identification of PTEN-Targeting MicroRNAs
No full textmicroRNAs (miRNAs) are a class of ~22nt long single-stranded RNA molecules that have come into light as negative regulators of gene expression at the post-transcriptional level. A growing body of evidence demonstrates that miRNAs are involved in numerous biological and pathological processes. Among the latter, microRNAs play a fundamental role in both cancer development and progression, acting either as oncosuppressor or oncogenic molecules by regulating key genes involved in cellular proliferation and/or survival. One such gene is Phosphatase and Tensin homolog deleted on chromosome 10 (PTEN), which exerts its tumor-suppressive function by inhibiting the Akt/PI3K signaling pathway.PTEN regulation by microRNAs has been extensively studied and PTEN targeting microRNAs are the focus of dozens of publications. This chapter is intended as a resource that can guide through the identification and validation PTEN-targeting miRNAs, using both bioinformatic-based approaches as well as some newly developed and unbiased high-throughput techniques, focusing on the more tricky aspects of these processes
Enhancing Video Surveillance with Usage Control and Privacy-Preserving Solutions
No full textNowadays, the use of video surveillance systems for protecting critical environment is becoming more and more popular. On the one hand, video surveillance systems should be able to detect the presence of unauthorized people in the monitored environments to provide effective physical security. On the other hand, video surveillance systems should be also able to preserve the privacy of authorized people. Moreover, some scenarios require that the right of a person to stay in a monitored room depends on dynamic factors that change over time. To consider these aspects, our paper proposes a video surveillance framework based on the Usage Control model. This framework enforces security policies which continuously control that the people who enter the monitored environment have the permission to stay there. Then, we present two solutions to make our video surveillance framework privacy-preserving. The first solution considers that when the security policy is violated, the video surveillance system records the video stream captured by the video cameras installed in the monitored environment. The second solution uses the Secure-Two party Computation technique to identify the people in the monitored environment in a privacy-preserving way. In this paper, we present the architecture of the proposed framework, we provide an example of Usage Control policy in a real scenario and we describe the main details of our two implementations