1,720,959 research outputs found
Studio della composizione della dieta di Lepus corsicanus in un'area SIC-ZPS della Basilicata mediante analisi istologica dei tessuti vegetali rinvenuti nei pellet fecali.
No full textLo studio delle relazioni trofiche (preferenze alimentari, distribuzione e disponibilità quali- quantitativa delle risorse) può contribuire ad individuare e tutelare componenti essenziali del habitat della lepre italica (Lepus corsicanus), specie endemica minacciata. L’unico studio sul comportamento trofico della specie, realizzato nel Parco Regionale dell’Etna, ha evidenziato una dieta molto diversificata, con preferenza per le graminacee. Abbiamo indagato la composizione della dieta di L. corsicanus in ambiente appenninico, nell’area SIC/ZPS “Foresta di Gallipoli Cognato” (4286 ha). Ai fini dello studio della dieta sono stati individuati tre siti campione con esclusiva presenza di L. corsicanus (densità non inferiore a 5 capi/km2), con le seguenti caratteristiche fisionomico vegetazionali: A) Cugno del Pero (370 m s.l.m.): macchia-foresta a leccio e orniello (Viburno-Quercetum ilics s.l.), ripisilva lungo il Basento a pioppo nero e salice bianco (Roso sempervirenti-Populetum nigrae), cespuglieti termofili a Pyrus amygdaliformis, Crataegus monogyna, Pistacia lentiscus (Pruno-Rhamnetalia alaterni), rimboschimento a Pinus halepensis prevalente; B) Scannacapre (532 m s.l.m.): pascolo arborato con Quercus virgiliana e cespugli radi di C. monogyna, Prunus spinosa, P. amygdaliformis, Phyllirea latifolia (Pruno-Rhamnetalia alaterni, Thero-Brachypodietea); C) Caserma Cognato (810 m s.l.m.): querceto misto di Quercus cerris, Q. frainetto (Centaureo-Quercetum pubescentis s.l.) con diradamenti, radure e seminativi. Da marzo 2009 sono stati raccolti mensilmente pellet fecali e campioni vegetali da utilizzare per l’allestimento di preparati istologici e atlanti fotografici di confronto. Per il periodo primaverile-estivo 2009, sono stati allestiti 630 preparati istologici e raccolti circa 260 campioni di piante con evidenti segni di morso delle lepri, relativi a: foglie, fusti, bulbi, rizomi, fiori e frutti appartenenti a oltre 60 taxa. Nei preparati sono stati rinvenuti i seguenti tessuti: epidermide, mesofillo, margine fogliare, tricomi, xilema e parenchimi di riserva. Gli organi maggiormente appetiti sono risultati, in ordine decrescente: foglie (96%), fiori (2%), fusti (1%) e bulbi (1%). I tessuti più frequenti nei campioni fecali sono risultati epidermide (44%) e margine fogliare (20%), seguiti da mesofillo (19%), tricomi (13%), xilema (2,5%) e parenchimi di riserva (1,5%). Nel periodo estivo la dieta è risultata maggiormente differenziata in tutti i siti rispetto al periodo primaverile. In particolare, in primavera prevalgono erbe graminoidi e bulbose, quali Brachypodium sylvaticum, Allium sp. pl., Plantago serraria e Leopoldia comosa, mentre in estate le specie più frequenti sono: Cynodon dactylon, Plantago serraria e Brachypodium sylvaticum (Cugno del Pero); Trifolium pratense, Phlomis herba-ventie Lolium rigidum (Scannacapre); Carex distachya, Picris hieracioides, Agrimonia eupatoria e Centaurea solstitialis (Caserma Cognato). A fronte di una notevole disponibilità di piante appetibili, l’animale si nutre preferenzialmente di un limitato numero di specie (es. Plantago serraria, Brachypodium sylvaticum, Allium sp.pl.). I campionamenti in corso consentiranno di definire in modo più completo le esigenze trofiche dell’animale e di individuare le condizioni ambientali ottimali nelle quali attuare misure di tutela e conservazione
Study of Italian hare (Lepus corsicanus) in different habitats of southern Appennines in Basilicata region. I. Floristic composition of diet.
No full textIn the Park of Gallipoli Cognato was carried out a study on diet
composition of Italian hare. Faeces were monthly collected during
1 year in 3 different sites with the following botanical associations:
site 1 (370 m a.s.l.), Viburno-Quercetum ilicis, Roso sempervirenti-Populetum
nigrae, Pruno-Rhamnetalia alaterni; site 2 (532
m a.s.l.), Pruno-Rhamnetalia alaterni, Thero-Brachypodietea; site
3 (810 m a.s.l.), Centaureo-Quercetum pubescentis. From faeces,
by histological analysis, were identified 78 species
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
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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