1,720,957 research outputs found
A record of late Quaternary environments at lunette-lakes Bolac and Turangmoroke, Western Victoria, Australia, based on pollen and a range of non-pollen palynomorphs
No full textA palaeoecological record from Lakes Bolac and Turangmoroke details the changing nature of vegetation patterns, lake levels and climate in the drier part of the Victorian Western Plains over approximately the last 90,000 years. In addition to the routine palynological proxies of pollen, spores and charcoal, a range of non-pollen palynomorphs (remains of algae, fungi, insects and other invertebrates) was analysed and described and provides useful additional information on the ecology of past vegetation communities. A chronology for the record is provided by radiocarbon and refined optical luminescence dating in the upper part of the sequence, and the latter technique is used to provide a timeframe for the period beyond the radiocarbon limit. The record shows that during marine isotope stage (MIS) 5.1 and mid MIS 3 the regional vegetation was composed of open woodland dominated by Allocasuarina luehmannii type with low numbers of Banksia, Eucalyptus and other Myrtaceae under which a diverse understorey developed. During these times Lake Turangmoroke held fresh water of varying depths. The degree of representation of MIS 4 and MIS 3 in the record is uncertain owing to discontinuities resulting from the lake having periodically dried. A change to open grassland-steppe occurred shortly after 47,000 years ago and lake levels fluctuated considerably before the lake became shallow and saline. Open grassland-steppe continued through MIS 2 with almost no trees present while the aquatic flora reflected further lake level declines and increasing salinity. Driest conditions, indicated by deflation of lake sediments during lunette building, occurred between similar to 18,000 and similar to 11,000 cal yr BP. Open woodland in the early Holocene was dominated by A. verticillata type until partial replacement by Eucalyptus around 7000-8000 (14)C yr BP when the vegetation cover present at European arrival was established. (c) 2008 Elsevier B.V. All rights reserved
Observed relationships between El Niño-Southern Oscillation, rainfall variability and vegetation and fire history on Halmahera, Maluku, Indonesia
No full textA temporally high-resolution palynological study of the uppermost section of core MD98-2180 from Kau Bay, Halmahera, Indonesia, provides a vegetation and fire record covering the last 250 years. The record is compared with the Maluku Rainfall Index, Southern Oscillation Index (SOI) and southern hemisphere winter sea surface temperatures (SST) for the central Pacific Ocean based on instrumental data, as well as reconstructions of the SOI and the central Pacific SST and historically recorded El Nino events. The results show that significant El Nino events are generally associated with increased representation of Dipterocarpaceae pollen, probably reflecting the mass-flowering of this taxon during El Nino-Southern Oscillation (ENSO) droughts, and elevated charcoal levels, reflecting a greater incidence of fires during these extremely dry periods, while humid phases show increased fern numbers. Our findings demonstrate that pollen records 'ecological' in scale can provide useful additional proxy records of ENSO events
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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