1,721,026 research outputs found
Abundances of benthic invertebrates and related environmental variables over a 5-year sampling period in a glacier-fed stream used for hydropower generation (South Tyrol, Italy)
No full textStream benthic macroinvertebrates have been collected for a period of 5 consecutive years, twice a year (2015-2019, in April/May and in September/October), along a longitudinal transect of the Saldur stream, a near pristine glacier-fed stream located in South Tyrol, Italy (46°N, 10° E), part of the International Long Term Ecological Research (ILTER) network (site code: IT-25, LTER_EU_IT_100).
From year 2016 on, a small "run-of-river" (ROR) hydropower plant (max. 3,200 kW/year) started to operate on the stream, and the sampling sites were chosen accordingly, to examine its potential impact on the riverine ecosystem.
Organisms were collected through Surber samplings (0.0506 squared metres, mesh size 500 µm) in 6 sites at different elevation and distance from the glacial source and from the weir of the hydropower plant:
Saldur_1 (2,030 m a.s.l.; 4.962 km from glacial source; ~1 km upstream of the weir ),
Saldur_2A (2,016 m a.s.l.; 5.225 km from glacial source; ~100 m upstream of the weir),
Saldur_2B (2,006 m a.s.l.; 5.325 km from glacial source; located in the river stretch between the weir and the outlet pipe of the two sediment traps of the ROR hydropower plant, so ~ 100 m downstream of the weir);
Saldur_2C (1,997 m a.s.l.; 5.486 km from the glacial source; ~50 m downstream of the above mentioned outlet pipe and ~ 150 m downstream of site 2B);
Saldur_2D (1,779 m a.s.l.; 8.217 km from the glacial source; ~ 3,000 m downstream of the weir);
Saldur_3 (1,645 m a.s.l.; 11.123 km from the glacial source; ~ 6,000 m downstream of the weir).
In all sites, three different sub-samples were collected, and the main substrates present at each site were sampled (macrolithal - rocks of 20-40 cm, and mesolithal - rocks of 6-20 cm).
Faunal nomenclature fully complies with "Fauna Europaea" standard (https://fauna-eu.org).
Contextually, a set of environmental variables was measured (as spot-measurement) during the macroinvertebrate samplings: suspended solids (mL/L); specific conductance at 25° C (mS/cm), water temperature (°C), calculation of the bottom component of the Pfankuch index.
Whilst only in 2018 turbidity (NFU) was measured instead of suspended solids, and all the measurements were conducted using a multiparameter meter (HI9829, Hanna Instruments), for all the remaining years suspended solids were measured after 30 minutes of water sedimentation in a Imhoff cone, and specific conductance through a portable conductimeter (Cond 7, XS Instruments)
Abundances of benthic invertebrates over a 5-year sampling period in a glacier-fed stream used for hydropower generation (South Tyrol, Italy)
No full textStream benthic macroinvertebrates have been collected for a period of 6 consecutive years (2010-2015, from April to September, during the glacial melting) along a longitudinal transect of the Saldur stream, a near pristine glacier-fed stream located in South Tyrol, Italy (46°N, 10° E), part of the International Long Term Ecological Research (ILTER) network (site code: LTER_EU_IT_100).
Organisms were collected through Surber samplings (0.0506 squared metres, mesh size 500 µm) in 3 sites at different elevation and distance from the glacial source: Saldur 1 (2,030 m a.s.l.; 4.962 km), Saldur 2 (2,016 m a.s.l.; 5.325 km), Saldur 3 (1,645 m a.s.l.; 11.123 km)
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
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
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