1,720,986 research outputs found

    Dealing with disjunct populations of vascular plants: implications for assessing the effect of climate change

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    Species distribution models are the most widely used tool to predict species distributions for species conservation and assessment of climate change impact. However, they usually do not consider intraspecific ecological variation exhibited by many species. Overlooking the potential differentiation among groups of populations may lead to misplacing any conservation actions. This issue may be particularly relevant in species in which few populations with potential local adaptation occur, as in species with disjunct populations. Here, we used ecological niche modeling to analyze how the projections of current and future climatically suitable areas of 12 plant species can be affected using the whole taxa occurrences compared to occurrences from geographically disjunct populations. Niche analyses suggest that usually the disjunct group of populations selects the climatic conditions as similar as possible to the other according to climate availability. Integrating intraspecific variability only slightly increases models’ ability to predict species occurrences. However, it results in different predictions of the magnitude of range change. In some species, integrating or not integrating intraspecific variability may lead to opposite trend in projected range change. Our results suggest that integrating intraspecific variability does not strongly improve overall models’ accuracy, but it can result in considerably different conclusions about future range change. Consequently, accounting for intraspecific differentiation may enable the detection of potential local adaptations to new climate and so to design targeted conservation strategies

    Conservare la Flora di Spiaggia: il progetto PSAMMbeach.

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    PSAMMbeach è un progetto PSR – Misura 16.1, promosso e finanziato dalla Regione Liguria, che ha come obiettivo principale l’avvio di una nuova linea di coltura vivaistica sostenibile basata su piante di spiaggia, che per le loro caratteristiche consentono un risparmio idrico ed energetico durante tutta la fase produttiva. Diversi partners sono stati coinvolti: Confagricoltura come capofila del progetto, il CREA di Sanremo e il vivaio F.lli Rebella di Quiliano per la produzione e il DISTAV per la ricerca. Il monitoraggio della flora delle spiagge liguri avviato dal DISTAV ha permesso di scegliere le specie idonee per la filiera di produzione e si è occupato della raccolta sul territorio regionale del materiale per la propagazione (semi, materiale per talea e piante madri). Scelta del progetto è stata, infatti, quella di utilizzare esclusivamente materiale autoctono. Le piante sono state selezionate per il loro pregio floristico, andando a scegliere specie rare per la Liguria come Pancratium maritimum L., ma anche per la valenza estetica, includendo oltre alle psammofile anche altre specie proprie dell’ambiente costiero in senso lato, come ad esempio Glaucium flavum Crantz., Lagurus ovatus L., Crithmum maritimum L. e Lobularia maritima (L.) Desv. La commercializzazione delle piantine prodotte inizierà dalla prossima primavera, e nello stesso periodo si procederà a piantumare alcune di esse anche in aiuole e giardini pubblici e privati per promozione (il progetto è sostenuto anche da enti locali) e a reintrodurre in modo mirato alcuni esemplari in spiagge libere o private per rafforzare popolazioni depresse in Liguria, che negli ultimi decenni hanno patito le trasformazioni antropiche, con l’auspicio che in futuro si disperdano spontaneamente. Tutto ciò sarà accompagnato da attività di promozione e di divulgazione relative al progetto e alla flora di spiaggia, con la speranza di riuscire a creare una consapevolezza e una sensibilità nuova

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The 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

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    “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

    Appropriate Similarity Measures for Author Cocitation Analysis

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    We 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

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    We 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

    Author Index

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    koamabayili/VECTRON-author-checklist: VECTRON author checklist

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    We 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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