1,720,966 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

    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

    La Coturnice, Stato e Conservazione delle Popolazioni del Parco Nazionale del Cilento, Vallo di Diano e Alburni

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    The Rock Partridge (Alectoris graeca) is a gamebird belonging Galliformes (gallinaceous birds), a wide order of heavy-bodied ground-feeding birds including a lot of well-known species, like turkey, grouse, chicken, and pheasant. Galliformes count about 275 species, divided in 73 genus and 5 families. These are generally medium size to large terrestrial birds, with a short and generally strong bill, short wings and strong legs. They usually prefer to run rather than fly, but if necessary they fly on short distance. Sometimes, male has brightly coloured plumage as well as facial ornamentations such as wattles or crests. Galliformes have a varied diet, with foods taken ranging from vegetarian items (roots, leaves, tubers, fruits, seeds) and to small animals including insects. Phasianidae are the largest family of Galliformes and they include 155 species, among which the Rock Partridge. The Rock Partridge is linked to dry agro-pastoral mountains with heathland, grass and low scrub, rocky escarpments or crags and small agglomerations bushy (10-20% of the total surface area) used as shelters, or repairs from adverse weather conditions and predators. This species tends to avoid bare soil, probably for the greater difficulty in such contexts to find the trophic resources (seeds, sprouts, etc.). The presence of the Rock Partridge is negatively correlated to the wooded areas, probably for their minor trophic importance and the increased presence of predators (such as foxes and wild cat). The Rock Partridg is a typical mountain species that can be found between 800 and 2700 m with a maximum between 1000 and 1200 m in Apennine range. It prefers the mountain south side with a slope between a minimum of 30% to a maximum of 70% (higher values for the slopes with a gradient of 50-59%). Palearctic range of this bird involve Central and Eastern Europe; it is found throughout the Alps, from France to Austria, Central and Southern Apennines, and Sicily in Italy, in the Balkans, in Albania and in Greece. Three living subspecies are usually recognized , which differ in some aspects of their coloration and somewhat more according to molecular studies: A. graeca saxatilis (central rock partridge) in Southern half of the Alps to Bosnia and Appenines; A. g. whitakeri (Sicilian rock partridge) restricted to Sicily; A. g. graeca (eastern rock partridge) distributed from Bosnia to Greece and Bulgaria. The Rock Partridge has undergone a large decline since about 1950 throughout its entire distribution range and in some areas it seems to be even extinct. The IUCN (International Union for the Conservation of Nature) classifies this species as Threatened or Near Threatened in Red Data Books in most of its range. In Italy, A. graeca is evaluated as Vulnerable and it is listed in the first attachment of the Birds Directive (79/409/CEE) by European Union. Furthermore, BirdLife International includes it in SPEC 2 (Species of European Conservation Concern) category (species which have an unfavorable conservation status in Europe). Various phenomena are considered responsible for the decline of the Rock Partridge. The hunting pressure affects this species, so throughout districts of Campania it was forbidden, although there are in act several forms of poaching. The Rock Partridge is also affected by climate change, studies on French Alps suggest that the partridges experienced a rapid decline since 1994, with a minimum 1997-98, caused by freezing winters between ‘94 and ’96. Moreover, hybridization between different subspecies is one of the factors which seriously threatens the genetic integrity of the populations. It was recorded especially in the areas of transition between ranges of different species; for example, hybrids between A. rufa x A. greca (in Southern French) and A. chukar x A. greca (in Bulgaria and Romania) were recognized. Finally, human depopulation of rural mountain areas and the consequent abandonment of traditional land management represent a treat for partridges. In fact, tree and shrub encroachment leads to a decrease in fragmentation of the agro-pastoral landscape, patches suitable for partridges reduce in size and increase in mutual distance. The Rock Partridge, linked to the agro-pastoral habitat, has suffered negative effects through a reduction in connectivity. The opportunity for individuals to move between suitable patches is severely limited causing the development of small and isolated populations. The small size associated with the isolation state can be a serious threat for a lot of populations. Small populations, if reproductively isolated, are the most exposed to inbreeding. In general, raise in inbreeding creates unfavorable conditions (inbreeding depression) and affect reproductive capacity, adaptation to environmental changes, and disease resistance. Inbreeding can indeed lead to disadvantageous or lethal traits causing even extinction of population. The A. graeca decline is particularly pronounced in the Central and Southern Apennines, where it survives in small and fragmented populations. This species is present from Umbrian-Marchigiano Appennines to the Aspromonte (Marche, Umbria, Lazio, Abruzzo, Molise, Campania, Basilicata e Calabria regions) while it seems to be extinct in Northen Appennines, where it was considered present until the first decades of the last century. The total population is estimated to 1939 - 2436 couples, most of which (about 1500, accounting for 69-77% of the total) concentrated in Abruzzi. In Campania, the Rock Partridge has undergone a rapid decline since about 1960. Currently, the Cilento and Vallo di Diano National Park (a protected mountain area in Southern Italy) is the only area where the conspicuous Rock Partridge populations can be found. These populations, waiting for further analyses of the Matese mountains, may be considered the only autochthonous ones in Campania. Thanks to their geographical position they may be an important link between the central Apennines populations and those of Basilicata and Calabria. Also in Cilento, the status of A. graeca is affected by impact of human settlement: poaching and intensive hunting stress the few remaining populations; the introduction of congeneric allochthonous species could be the causes of interspecific competition or hybridization. In the mountain of Cilento, the abandonment of traditional agricultural practices and depopulation of rural areas cause profound changes in the landscape structure and function. The resulting isolation condition could lead the Rock Partridge population toward a bottleneck. It is a sharp reduction in the size of a population due to environmental events or human activities that can reduce the variation in the gene pool of a population. After a bottleneck event, the chance of inbreeding and genetic homogeneity increases and unfavoured alleles can accumulate. In consequence of population size reductions and the loss of genetic variation, the ability to survive for population at the mercy of environmental changes, is reduced. Our research, using molecular genetic marker, have shown that A. graeca populations of Cilento have signature of past bottleneck. Continuous monitoring of this population is essential to define a conservation strategy. Since 1998, a lot of studies were conducted by the Cilento and Vallo di Diano National Park Authority aimed to increase knowledge about the Rock Partridge and delineate suitable management and conservation plans. In the page of this book we tell about this long period research. We start from the estimation of size and distribution of this bird populations. Survey have started in the Park thanks to the involvement of academic researchers, birdwatchers, shepherds, hunters and their dogs. The Rock Partridge is an elusive animal and sniffer dogs are an efficient support for the census activities during the winter. In spring survey, in order to avoid any disturbance to breeding couples, was performed using a play-back method. Geographic Information System was implemented to identify suitable areas in the Park. Multivariate, spatially explicit model based on ecological niche factor analysis (ENFA) was used to predict the habitat suitability (HS) of the A. graeca and to examine the connectivity of the habitat in the study area. ENFA revealed about 42 areas (landscape patches) with 100% suitability for the species, corresponding to approximately 40,000 acres of study area. However, only 15 patches was equal or greater than the minimum vital extension for the bird and 9 of these 15 patches are characterized by the presence of stable units of A. graeca. In this patched landscape live a population scattered on nine mountain: M. Alburni, M. Motola, M. Serra Nuda, M. Cocuzzo delle Puglie, M. San Giacomo, M. Cerasuolo, M. Cervati, M. Faiatella and M. Raia del Pedale. In each mountain we performed about 10 km transect long, with fixed listening points for receiving the acoustic signal. At each point, calls were launched for 4 minutes; the following five minutes were spent to listening to the responses. The data collected in 1998 reveal the presence of small populations of Rock Partridge with an average density of less than 2 individuals/kmq in M. Alburni, M. Motola, M. Serra Nuda, M. St. Giacomo, M. Cervati, M. Faiatella and M. Raia Pedale. Analyses of population in the 2004 showed a slow but worrying demographic decline (1.63 ind/kmq). The number of breeding pairs were about 84 in 2006 when the densities increase to 2.17 ind/kmq remaining so until 2014. In fact, census in the spring and autumn seasons of 2014 has led to prove the presence of the species with he same densities of 2006 in the areas of M.ti Alburni, M.te Motola, M.te San Giacomo, Cervati, M.te Faiatella e Raia del Pedale. The population of Serra Nuda e M.te Cerasuolo seem to disappear. The connectivity analysis shows that there are a isolated unit localized to north (mountains of Alburni) and other remained populations of Partridge to south (mountains of Motola, Serra Nuda, Cerasuolo, Cervati, Faiatella, Raia del Pedale). One of the main management activities of the species in the Park is to preserve and enhance the connectivity among available areas that ensures species survival through maintaining gene flow, genetic variability and providing a source for individuals to offset losses caused by poaching, predation or natural disasters. Identifying and protecting threatened habitats, while balancing the requirements of faunal management policies, economic stability and other human needs, is a key conservation objective. However, the identification and protection of suitable areas are not sufficient to ensure long-term species conservation; we believe that applying management strategies based on the restoration of connectivity through financial support and promotion of traditional agro-pastoral practices is essential for the preservation of Rock Partridge

    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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