1,721,030 research outputs found
Reef status in the Rasfari region (North Malé Atoll, Maldives) five years before the mass mortality event of 1998
No full textThe Maldives was severely hit by massive coral bleaching and subsequent mortality in 1998. The results
of reef monitoring in the following years have supported contrasting views about their recovery
potential, partly because of the scarcity of information on the situation before 1998. Quantitative data on
coral assemblages collected in 1993 in the Rasfari region (North Male ́ Atoll) may provide a base-line for
the evaluation of the present status of the Maldivian reefs. Five years before the 1998 mortality, most
coral communities appeared to be similar, in terms of both coral cover and growth-form composition, to
those described in 1958 and 1964, notwithstanding increased human pressure and local events such as
minor bleaching episodes in 1987 and crown-of-thorns starfish (COTS) attacks in 1989. Three lessons can
be learnt from these results to help to understand the present situation, some ten years after the 1998
mass mortality. First, Maldivian reefs proved in the past to be capable of maintaining flourishing coral life
despite various disturbances. Second, four years had been sufficient for complete reef recovery after
a (minor) bleaching event. Third, recovery after both COTS attack and bleaching follows a predictable
path suggesting that the presence of a three-dimensional community structure, which should reduce
post settlement mortality of coral recruits, is essential for rapid coral recovery. As coral recruitment
remains high and large tabular Acropora colonies are now reappearing, it is expected that Maldivian reefs
should return to their original condition within the next few years
THERMOHALINE VARIABILITY AND ANTARCTIC BOTTOM WATER FORMATION AT THE ROSS SEA SHELF BREAK
No full textTHERMOHALINE VARIABILITY AND ANTARCTIC BOTTOM WATER FORMATION AT THE ROSS SEA SHELF BREAK
No full textWe use hydrological and current meter data collected in the Ross Sea, Antarctica between 1995 and 2006 to describe the spatial and temporal variability of water masses involved in the production of Antarctic Bottom Water (AABW). Data were collected in two regions of known outflows of dense shelf water in this region; the Drygalski Trough (DT) and the Glomar-Challenger Trough (GCT). Dense shelf water just inshore of the shelf break is dominated by High Salinity Shelf Water (HSSW) in the DT and Ice Shelf Water (ISW) in the GCT. The HSSW in the northern DT freshened by 0.06 in 11 y, while the ISW in the northern GCT freshened by 0.04 in 8 y and warmed by 0.04 °C in 11 y, dominated by a rapid warming during austral summer 2001/02. The Antarctic Slope Front separating the warm Circumpolar Deep Water (CDW) from the shelf waters is more stable near GCT than near DT, with CDW and mixing products being found on the outer DT shelf but not on the outer GCT shelf. The different source waters and mixing processes at the two sites lead to production of AABW with different thermohaline characteristics in the central and western Ross Sea. Multi-year time series of hydrography and currents at long-term moorings within 100 km of the shelf break in both troughs confirm the interannual signals in the dense shelf water and reveal the seasonal cycle of water mass properties. Near the DT the HSSW salinities experienced maxima in March/April and minima in September/October. The ISW in the GCT is warmest in March/April and coolest between August and October. Mooring data also demonstrate significant high-frequency variability associated with tides and other processes. Wavelet analysis of near-bottom moored sensors sampling the dense water cascade over the continental slope west of the GCT shows intermittent energetic pulses of cold, dense water with periods from 32 h to 5 days
The high resolution combined topographic model of Panarea island (Aeolian island, Italy)
No full textAerial digital photogrammetry, aerial laser scanning and multibeam bathymetry are integrated to generate the first 3-D high resolution DTMM of the volcanic island of Panarea
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
Deep-sea polychaetes (Annelida) from the Malta Escarpment (western Ionian Sea)
No full textThe polychaete assemblages from an escarpment area in the western Ionian Sea are characterised in terms of species richness, evenness and trophic composition. Moreover, the first occurrence of the genus Barantolla in the Mediterranean Sea, and of Lumbrinerides carpinei and Exogone (Parexogone) campoyi in Italian waters, is reported. Aricidea trilobata Laubier and Ramos, 1974 is redescribed on the basis of new material with the new name Aricidea (Acmira) jeaneteae, together with a brief description of two deep-water species belonging to the genus Levinsenia
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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