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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
Stratigraphic architecture of Late Quaternary deposits in the Lower Arno Plain (Tuscany, Italy)
No full textDetailed sedimentological investigation of two continuously-cored boreholes, up to 106 m deep,
combined with stratigraphic analysis of about 300 well logs performed for water research in the area between
Cascina and the Tyrrhenian coast, reveal subsurface stratigraphy of Late Quaternary deposits in the lower Arno
Plain.
Facies analysis of the cores allows identification of twelve different facies associations, grouped into alluvial
and coastal depositional systems. A stratigraphic cross section, roughly parallel to present Arno River and 30 km
long, shows the presence of two trangressive-regressive sequences, attributed to the last two interglacial-glacial
cycles (base of OIS 1 and 5e, respectively). Despite significant facies variability from proximal to distal locations,
the basal transgressive surfaces appear as the most readily identifiable features from both core and borehole data,
and constitute a stratigraphic marker that can be physically traced across the entire study area.
The high resolution stratigraphic data shown in this paper are in marked contrast with previous work, and provide
a new stratigraphic framework for the upper portion of the Viareggio Basin
Characterization of aquifer systems from high-resolution subsurface stratigraphy: the case of the eastern Valdarno basin (Tuscany, Italy)
No full textRealistic models of ground water circulation and transport in modern alluvial
and coastal plains demand an accurate reconstruction of subsurface
sedimentary architecture. In this study, we propose the characterization of a
multilayered aquifer from the subsiding eastern Valdarno Basin, a strategic
area far both water research and pollution issues, between the city of
Pontedera and S. Croce.
An integrated sedimentological, stratigraphic and micropaleontological study of
six continuously cored boreholes allows the detailed reconstruction of Pliocene
to Quaternary stratigraphy in the uppermost 100 m, and shows how a
multidisciplinary approach may represent a successful tool to define
three-dimensional facies relationships with in sedimentary bodies, and thus
aquifer geometries. Moreover, AMS 14C dates associated to Sr isotope data
prompt to place the identified stratigraphic units in a worthy
chronostratigraphic framework, with a coherent depositional evolution in terms
of space and time.
The study area, oriented SW-NE along the Arno River course, is rimmed to the
south and to the north by the Pisa and the Cerbaie Hills, respectively, both
formed by Plio-Quaternary marine and continental deposits. A fault, located
a long the southern margin of the Cerbaie Hills, causes the NNW-dipping, below
the Arno-plain, of the Plio-Quaternary deposits cropping out o n the Pisa Hills.
Stratigraphic architecture in the study area is varied. Except far the Holocene
succession, consisting mainly of fine-grained alluvial-plain deposits lying onto
transgressive swamp deposits and showing a homogenous spatial distribution,
the pre-Holocene deposits exhibit noticeable distinct features west and east of
Pontedera, respectively, due to the activity of a normal fault with an Apenninic
orientation, causing the lowering of the west side of the study area. A thick
Pleistocene alluvial succession, made up by a cyclic alternation of
coarse-grained fluvial channel and fine-grained floodplain deposits, is recorded
beneath Pontedera, whereas eastwards the stratigraphic sequence is
characterized by Early-Middle Pliocene deposits, related to coastal-shallow
marine sands with very subordinate alluvial facies.
Given this structural setting, the reconstruction of stratigraphic architecture
leads to the identification, in the uppermost 100 m, of a multilayered confined
aquifer consisting of five aquifer systems (A-E) ranging in age between the
Holocene and the Early-Middle Pliocene.
Aquifer system A developed during the Holocene and exhibits a markedly
lenticular geometry recording the recent dynamics of the Arno River. The
underlying aquifer system (B), Lower-Middle Pleistocene-Holocene in age,
consists of sands an d gravels of fluvial origin and is recorded only in the
western sector of the examined area. The lower three aquifer systems (C-D-E),
characterizing the eastern sector of the study area, mainly consist of sandy
shallow-marine deposits, Early to Middle Pliocene in age, showing a cyclic
arrangement.
The Quaternary aquifer systems (A-B) exhibit a strongly lenticular shape,
reflecting their fluvial origin, while the Early-Middle Pliocene aquifer systems
(C-D-E) display a higher lateral continuity, as expected from sedimentary
bodies deposited in coastal-littoral setting.
The geological framework and the structural setting suggest the identification
of water recharge areas in the Middle Pliocene sandy deposits cropping out on
the Pisa Hills, taking into account their NNW dipping toward the Arno Plain
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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