1,720,963 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
South American Climate Dynamics and Evolution of the Andes.
Get PDFReconstructing the uplift history of the Andean Plateau (AP) provides important constraints for evaluating tectonic and geodynamic models of orogenesis and plateau formation. Recent elevation reconstructions of the AP, mainly based on stable isotope paleoaltimetry, suggest a rapid and recent rise of ~2.5±1 km of elevation
of the central Andes during the Miocene (10-6 Ma) in response to lithospheric delamination.
However, this uplift scenario is based on the assumption that climate did not change during deposition of paleoaltimetry proxies, and is inconsistent with geological evidence that implies Andean elevations of >2 km at 19-13 Ma. To address these issues, this thesis utilizes regional general circulation models (RegCM3.0,
REMOiso5.0) to quantify changes in South American climate as a function of AP uplift and to evaluate the effects of surface uplift and climate change on the processes that control stable oxygen isotopic compositions in meteoric waters (d18Op). General results show that the Andes have a significant impact on moisture transport, deep convective processes, and precipitation over much of South America through
mechanical forcing of the South American low-level jet and topographic blocking of westerly flow from the Pacific Ocean. In particular, Andean surface uplift intensifies convergence, orographic lifting, moisture transport, and latent heat release, which fuels convection and leads to an increase in precipitation along the eastern flank. Precipitation amount, water vapor source, wind pattern, and temperature are the
factors that control d18Op along the Andes. Changes in the climatic conditions in response to Andean surface uplift influence isotopic source and amount effects and consequently d18Op. Changes in simulated d18Op are not systematic with an increase in Andean surface elevations, but differ in magnitude and timing across the AP. Low d18Op compositions of Miocene carbonates are consistent with simulated fractionation processes at elevations above 3000 m, and the 3-4‰ decrease in carbonate d18Op is smaller than the >5‰ decrease in d18Op simulated for Andean surface uplift from ~3000 to 4000 m. Model result suggest that the isotopic signal preserved in Miocene
Andean carbonates reflects regional changes in low-level atmospheric circulation and
precipitation associated with relatively minor (~1 km) surface uplift.PhDGeologyUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/84526/1/nadinsel_2.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/84526/2/nadinsel_1.pd
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
Late Miocene expansion of grasslands in northwest Argentina linked to shifting hydroclimate: A complex interaction among tectonics, climate, and ecology
No full textFactors driving the late Miocene expansion of C4 grasses remain widely debated. Here, we explored the role of climate and fire in controlling the abundance of C4 vegetation in the Angastaco Basin (Palo Pintado area) and La Viña Basin, NW Argentina, during the late Miocene (ca. 14−5.33 Ma). From paleosol horizons, we reconstructed paleoclimate and paleovegetation conditions using phytolith assemblages, geochemical and isotopic proxies, and polycyclic aromatic hydrocarbons (PAHs) to determine fire input. Our paleoclimate reconstructions suggest a stable mean annual temperature (MAT) of ∼10 °C and a gradual decline in mean annual precipitation (MAP) from 1100 mm yr−1 to 850 mm yr−1. Paleovegetation reconstructions from carbon isotopic composition and phytolith assemblages show a maximum of ∼15% C4 vegetation by 6 Ma. No significant increases in fire occurrence or establishment of fire feedbacks were identified from the PAH data. Though low in abundance (∼3% on average), our data identified the presence of C4 grass by the late Miocene. The lack of significant C4 expansion in this region was likely controlled by the changing hydroclimatic conditions associated with the Andes mountain range—increasing aridity and elevation constraints along with the lack of a fire feedback might have limited the distribution of C4 vegetation.Fil: Azmi, Iffat. North Carolina State University; Estados UnidosFil: Hyland, Ethan. North Carolina State University; Estados UnidosFil: Cotton, Jennifer. California State University Northridge;Fil: Ghosh, Adit. University of Southern California; Estados UnidosFil: Raigemborn, María Sol. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Geológicas. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Investigaciones Geológicas; ArgentinaFil: Tineo, David. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Geológicas. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Investigaciones Geológicas; ArgentinaFil: Hauswirth, Scott. California State University Northridge;Fil: Insel, Nadja. Northeastern Illinois University (northeastern Illinois)
- …
