1,720,975 research outputs found
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Get PDFWe 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
Structural plasticity at the input stage of the adult cerebellar cortex
Get PDFIn the last decades, a growing amount of evidence has showed that the adult brain is capable of undergoing dramatic reorganisation: learning new skills or acquiring novel experiences determine brain responses in order to reflect the changing circumstances. Changes in behaviour and brain function are probably accompanied by structural alterations in neuronal cells: while extensive descriptions of local rearrangements driven by experience during postnatal development have been provided, the adult brain was classically described to be resistant to such structural modifications. Nevertheless, recent studies convincingly showed that the adult brain is able not only to adapt synaptic transmission, but also to undergo remodelling of pre- and postsynaptic compartments in response to experience. Plasticity phenomena have been generally described for either pre- or postsynaptic compartments within small cortical fields, thus not fully clarifying the influence of structural remodelling on the synaptic transmission, on the neuronal behaviour (e.g. global versus local behaviour of a given axonal projection) and, lastly, on the circuit connectivity. In addition, considerable effort is currently made in order to establish a causal relationship between synaptic, structural and representational or topographic map plasticity. In order to address, at least in part, these questions, we exploited the simple and well-characterized cerebellar circuitry: this system has long been known as a centre for fine motor control and sensorymotor integration; moreover, in the past decade, new results have suggested an involvement of the cerebellum in cognitive and emotional functions. In addition, the cerebellum is a brain region endowed with a high degree of structural plasticity during development, as well as in the adulthood, not only following damage, but also in order to maintain its normal architecture under the influence of activity. The cerebellar anatomy is characterized by a simple and stereotyped connectivity between readily identifiable neurons, and therefore allows the investigation of synaptic rearrangements on a comprehensive scale. We focused our attention on the input stage of the vermal lobule V, namely at the synapse between mossy fiber (MF) terminals and granule cell (GC) dendrites. MF axons convey multimodal sensory information from distinct sources, such as spinal cord, vestibular system and cerebral cortex. The physiological properties and the anatomical arrangement at this stage, make the MF-GC synapse an advantageous system to investigate pre- and postsynaptic structural plasticity induced by experience. Here, we used two distinct behavioural paradigms: in one case, mice were housed in an enriched environment (EE), in order to provide social interactions and extensive sensorymotor stimulation. In a second set of experiments, mice were trained to associate a neutral stimulus with an aversive one, exploiting a pavlovian learning paradigm that relies on fear emotion (fear conditioning, FC). We combined these tasks with large-scale confocal imaging in transgenic mouse lines that express membrane-targeted GFP in few neuronal cells, thus revealing their morphology in crisp details. This approach allowed us to solve and analyze entire MF projections, and related presynaptic terminals, as well as GC dendritic compartments. In general, we found that distinct experiences elicit substantially different remodelling events, in terms of structural outcome and time course. Upon EE, the MF-GC connectivity is profoundly altered in the properties of the afferent projections and in the putative amplification and transmission of the sensory information. The refinement of the connectivity (i.e. the number of presynaptic inputs per cell) is particularly altered in animals that were reared since birth in the enriched context; but a similar robust remodelling of single synaptic units (i.e. the dendritic endings) also occured in animals that experienced EE only in the adulthood. We further found that FC triggers a stepwise remodelling of the local connectivity at the MF-GC synapse, which proceeds for several days after the training and affects the whole population; the extent and quality of remodelling is lobule-specific and can be further modulated according to subsequent experience. The structural rearrangements we observed upon distinct experiences show that the adult cerebellar system is able to undergo extensive reshaping of its connectivity and synaptic organization. Complementary evidence about synaptic transmission at the MF-GC synapse upon EE and FC would help to assess a correlation between anatomical and functional properties
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