1,720,964 research outputs found
Ecological implications of wood anatomy, ring growth and shoot allometry of Mediterranean maquis species
Full text linkWood anatomical and structural features are key elements in the water relations of plants. To verify if the plants grown in four sites characterized by different climatic gradients modify the distribution of biomass were recorded biometric and wood features in five shrub species (3 individual for species) asQuercus ilex,Arbutus unedo,Phyllirea latifolia,Pistacia lentiscus,Cistus monspeliensistypical of Mediterranean ecosystems in the Sardinia region.The characterization of the species has required the measurement of the following parameters: leaf area (Aleaf), leaf dry weight (PS), specific leaf area (SLA), amplitude of the growth rings and mean diameter of the xylem vessels of the basal portion of the stem. The research has also provided the integration of dendrochronological analysis of ring woody with climate data (precipitation and temperature) of the study sites examined and the analysis of the anatomical features of the wood at the ultrastructural level. Through the observation of digitized photos of microsections transverse, have been measured wood vessels diameter. Our results suggested that aridity, rather than winter temperature, controls stem xylem response in the studied shrub species.The study aims to provide information on the ecological role of plant species under study and the functions of the conduction is the key to survival in conditions of stress caused summer aridity
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
Comparative ecological network analysis: an application to Italy
Full text linkEcological networks (ENs), i.e. compounds of a set of patches interconnected through a set of corridors, are major strategies for counteracting landscape fragmentation in stressed urban, peri-urban and rural domains. They are adopted in many cases worldwide and their success or difficult rooting can be used as a living indicator of the inclination of human settlements to favour the development of green systems. We aim at constructing a network analysis method and testing it to the comparative study of two ENs to be developed in Sassari and Nuoro, Italy. We will study ENs with the same number of nodes, analyse the size of the patches, and scrutinize the main variables expressing the topological and weighted centrality. This approach allows us to locate the hotspots of the ENs, i.e. the places that need to be protected from external negative drivers. Results demonstrate that the method is useful, as it helps finding similarities and dissimilarities in different ecological systems and confirms that network analysis has very good potential when applied in a comparative modality
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
Comparing ecological networks in peri-urban landscapes: an application to Italy
No full textEcological networks consist of ensembles of habitat areas connected through material or immaterial corridors and are one the major counteractions to landscape fragmentation, i.e. the process of subdivision of large portion of green zones into smaller and more isolated areas. In this paper we study two ecological networks for the towns of Nuoro and Sassari (Italy) by applying complex network analysis tools able to describe their structure through simple and intuitive measures. Results are interesting, as they comparatively provide us with useful indication about the basic characteristics and the most central patches of the systems
- …
