1,720,987 research outputs found

    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

    Isafruit, progetto europeo per favorire e migliorare il consumo di frutta

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    Nei giorni 20-22 giugno scorso si è tenuta presso la Facoltà di Agraria dell’Università di Bologna la 2a General Assembly del Progetto integrato europeo Isafruit, con il concreto sostegno della Facoltà di Agraria, della Regione Emilia Romagna e delle principali organizzazioni di produttori frutticoli italiani. Questo progetto è, tra quelli dedicati esclusivamente alla frutta, il maggiore sia per entità del budget totale, sia per entità del finanziamento Ue, nonché per il numero di partner partecipanti

    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

    Moderato ombreggiamento in pesco: effetti su consumo idrico, assimilazione e ripartizione dell’energia

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    Il processo fotosintetico, alla base dell’incremento della sostanza secca nelle piante, risulta essere strettamente legato all’intensità luminosa. Tuttavia al di sopra di una determinata soglia di irradianza (punto di saturazione) il tasso fotosintetico non mostra alcun incremento, raggiungendo uno stato stazionario. L’eccesso di energia radiante, oltre ad enfatizzare le perdite dovute ai processi di fotoinattivazione e foto protezione (Non Photochemical Quenching, trasporti elettronici alternativi e foto respirazione), comporta un incremento della temperatura ed un relativo aumento dei consumi idrici dovuti alla traspirazione fogliare. Una possibile strategia che la pianta opera per contrastare le perdite idriche consiste nel modulare l’apertura stomatica, sebbene questo comporti una diminuzione dell’organicazione della CO2 ed un incremento della temperatura interna degli organi fotosintetici. Nel presente lavoro vengono valutate e confrontate le performance produttive, fotosintetiche, lo stato idrico e l’entità dei meccanismi fotoprotettivi e di fotoinattivazione di piante di pesco (cv Alice col.) sottoposte a regimi luminosi di piena luce e di moderato ombreggiamento (40%) attraverso apprestamenti protettivi. La riduzione della radiazione incidente di circa il 40% non ha fatto registrare alcun decremento della fotosintesi netta mentre, in combinazione con il relativo abbassamento della temperatura occorso sotto rete ombreggiante, ha determinato il decremento della traspirazione e del potenziale idrico delle foglie ed un corrispettivo incremento dell’efficienza d’uso dell’acqua. La radiazione incidente in eccesso è stata indirizzata principalmente al processo fotoprotettivo di Non Photochemical Quenching, capace di dissipare fino al 68% della luce assorbita dalle foglie, coadiuvato dai trasporti elettronici alternativi e dalla foto respirazione. Gli alberi sottoposti a regime di moderato ombreggiamento hanno mostrato produzioni più elevate attribuibili, probabilmente, ad un miglior stato idrico delle piante ed alle mancate perdite di fotosintati determinate dai processi fotoprotettivi e di foto inattivazione

    Gestione dell’energia radiante nelle piante da frutto: utilizzazione, foto-protezione e foto-danno. Quali implicazioni per la produttività?

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    The energetic basis of orchard productivity lies in the interaction between the tree and sunlight. The light intercepted by a plant is linearly related to the amount of dry matter it produces. This concept drew the evolution of the new, intensive orchard planting systems, although this dependence seems to be more subordinate to planting system rather than light intensity. At whole plant level not always the increase of irradiance determines productivity improvement. One of the reasons can be the plant intrinsic un-efficiency in using energy. Generally in full light only the 5–10% of the total incoming photosynthetic photon flux density (PPFD) is allocated to net photosynthesis. Therefore preserving or improving this efficiency becomes pivotal for scientist and fruit growers. Net photosynthesis increases with light until the saturation point and additional PPFD doesn’t improve carboxylation. In several parts of the world, under clear sky the PPFD reaches commonly 2000 μmol photons m-2 s-1 or above, and about 50% of the incoming light is enough for reaching the saturating point in most plant species. On the other hand, about half of the available light may be in excess. Even tough a conspicuous energy amount is reflected or transmitted, plants can not avoid to absorb photons in excess. The chlorophyll over-excitation promotes the reactive oxygen species (ROS) production increasing the photoinhibition (photo-damage) risks. The dangerous consequences of photoinhibition forced plants to evolve a complex and multilevel machine able to dissipate the energy excess quenching heat (Non Photochemical Quenching), moving electrons (water-water cycle, cyclic transport around PSI, glutathione-ascorbate cycle and photorespiration) and scavenging the generated ROS. The price plants must pay for this equipment is the use of CO2 and reducing power with a consequent decrease of the photosynthetic efficiency, both because some photons are not used for carboxylation and an effective CO2 and reducing power loss occurs. The wide photo-protective apparatus, although is not able to cope with the excessive incoming energy, therefore photo-damage occurs. Each event increasing the photon pressure and/or decreasing the efficiency of the described photo-protective mechanisms (i.e. thermal stress, water and nutritional deficiency) can emphasize the photoinhibition. Likely in nature a small amount of not damaged photo-systems is found because of the effective, efficient and energy consuming recovery system. Since the damaged PSII is quickly repaired with energy expense, it would be interesting to investigate how much PSII recovery costs to plant productivity. This review purposes to improve the knowledge about the several strategies accomplished for managing the incoming energy and the light excess implication on photo-damage in plants. Furthermore the chlorophyll fluorescence measure technique is described. This is the most useful method, particularly because it can be used in vivo as well and it is possible to quantify and discriminate the contribution of pathways in which the incoming photon pressure is engaged. Finally some cases of light excess linked with abiotic stresses and particular physiological condition on fruit species are reported

    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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