1,720,980 research outputs found
Utilizzo di immagini satellitari nella gestione post evento degli incendi boschivi
Full text linkL’area Mediterranea è sistematicamente colpita da incendi che danneggiano vaste aree vegetate. Gli incendi boschivi hanno un impatto rilevante sugli ecosistemi e possono causare fenomeni di erosione del terreno, instabilità dei pendii, tendenza alla desertificazione. L’impatto interessa anche l’ambito economico colpito dall’inevitabile diminuzione del turismo.
Ogni anno, in alcune aree del Mediterraneo, come l’Italia, la Francia, il Portogallo, la Spagna e la Grecia, centinaia di migliaia di ettari di foreste sono vittima degli incendi [1]: circa 65000 incendi bruciano approssimativamente 500000 ettari di aree vegetate. Negli ultimi 30 anni, nonostante le nuove tecniche antincendio, le diverse strategie per il contenimento e la tecnologia per l’informazione e la comunicazione, lo scenario non è cambiato. Per apportare miglioramenti nell’informazione e prevenire gli incendi boschivi, è necessario valorizzare l’uso di prodotti derivanti da misure satellitari, i sistemi di rivelazione degli incendi mediante osservazione da terra e dallo spazio ed è necessario migliorare la stima degli effetti dell’incendio sulla vegetazione per stabilire la priorità per gli interventi di ripristino.
Lo scopo del progetto europeo PREFER (Space-based Information Support for Prevention and REcovery of Forest Fires Emergency in the MediteRranean Area) è generare prodotti a supporto delle attività di prevenzione incendi e la fase di recupero e ricostruzione [2], [3].
Il lavoro, svolto grazie al coinvolgimento in questo progetto Europeo, riguarda lo sviluppo di una metodologia per la generazione di mappe di severità del danno da incendio sulla vegetazione (fire damage severity maps) che rientra nell’attività di recupero e ricostruzione. Le mappe vengono ottenute mediante un algoritmo automatico che, utilizzando immagini Landsat 8 ad alta risoluzione spaziale ( 30 m) e bassa risoluzione temporale (16 giorni), calcola gli indici differential Normalized Burn Ratio (DNBR), Burn Severity Index (BSI) e Damage Severity Index (DSI) [4]. Con le soglie del danno per l’indice DSI si ottengono le soglie per gli altri indici e vengono così generate tre mappe del livello di danno per ogni area bruciata.
I risultati ottenuti sono validati con immagini RapidEye ad altissima risoluzione spaziale ( 5 m) prima e dopo l’evento e con foto acquisite in situ.
Viene studiata inoltre l’influenza dell’atmosfera e degli aerosol sulla stima del livello del danno
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
The transcription activation function of C/EBPalpha is required for induction of granulocytic differentiation
No full textThe CCAAT/enhancer binding protein-a. (C/EBPalpha) is a transcription factor required for differentiation of myeloid progenitors. In addition to specific DNA binding, C/EBPa is also involved in protein-protein interactions, some of which (p21, Cdk2/Cdk4, E2F) appear to be required for inhibition of proliferation and possibly differentiation. To investigate the mechanisms of C/EBPalpha-induced granulocytic differentiation, we generated C/EBPalpha mutants reportedly defective in DNA binding, transactivation, and Cdk2/Cdk4 and E2F interaction and assessed their effects in a myeloid precursor cell line, primary bone marrow and C/EBPalpha knockout fetal liver precursor cells. We show here that the DNA binding-deficient Lys298Glu mutant, the E2F binding-deficient basic region mutant 2 (BRM-2) carrying the IIe294AIa and Arg 47AIa substitutions, and the transactivation-deficient N-terminus truncated p30 mutant all fall to promote differentiation on ectopic expression in myeloid precursor cells. By contrast, ectopic expression of the Cdk2/ Cdk4 interaction-deficient Delta177-191 mutant promotes differentiation and induces gene expression as effectively as wildtype C/EBPa. Thus, the integrity of the transactivation and DNA binding domains, but not of the Cdk2/Cdk4 interaction region, is necessary for C/EBPalpha-induced differentiation. Since the E2F binding-deficient BRM-2 mutant interacted with E2F-1 but failed to activate gene expression, our results lend support to the hypothesis that activation of gene transcription is the determining factor in C/EBPalpha-dependent differentiation
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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