1,721,085 research outputs found
First confirmed record of the Lessepsian migrant Pteragogus pelycus Randall, 1981 (Teleostei: Labridae) for the North African coasts
Full text link4 pages, 2 figuresOn July 2010, a single specimen of Pteragogus pelycus was captured by gillnets along the coasts of Alexandria, Egypt (approximate position 31°14′N, 29°55′E) between 15 and 25 m of depth. This observation represents the first confirmed record of this species from the North African coastsThis study was supported by the EuroMediterranean Center for Climatic Changes and the Italian Ministry for the Environment and the Territory (Project: The impacts of biological invasions and climate change on the biodiversity of the Mediterranean Sea), and partially supported by the EU Mediterranean Sea Acidification under a changing climate project (MedSeA; grant agreement 265103)Peer reviewe
Trophic relationships at intrannual spatial and temporal scales of macro and megafauna around a submarine canyon off the Catalonian coast (western Mediterranean)
No full textInfluence of environmental variables on the spatio-temporal dynamics of bentho-pelagic assemblages in the middle slope of the Balearic Basin (NW Mediterranean)
No full textNile damming as plausible cause of extinction and drop in abundance of deep-sea shrimp in the western Mediterranean over broad spatial scales
No full text9 pages, 4 figures, 2 tablesGreatly increased retention of flow in Nile River reservoirs was initiated in 1964, after completion of the Aswan High Dam, which induced important oceanographic changes in the Mediterranean Sea, including deep waters (below a depth of 150 m). Based on an analysis of data series starting in the 1940s/1950s, the giant red shrimp Aristaeomorpha foliacea has become locally extinct off of the Catalonian coasts (and elsewhere in the northwestern Mediterranean) at depths of 400–900 m, with a simultaneous and significant drop in the catches of red shrimp, Aristeus antennatus, in the second half of the 1960s. The extinction and sharp decline of deep-shrimp populations off Catalonian coast (at ca. 3200 km westwards from Nile Delta) followed the 1964 drop in Nile discharge with a delay of ca. 3–5 yrs (breakpoint analysis applied to data series). The breakpoints detected in the second half of 1960s both in Nile runoff and shrimps’ abundance were independent of climatic events in the study area (e.g. changes in NAO) and occurred before the increase in fishing effort off Catalonian coasts (breakpoint in 1973–1974). The Levantine Intermediate Water (LIW), inhabited by A. foliacea in the western Basin, had significant temperature (T) and salinity (S) increases in the 1950–1970 period, and Nile damming has contributed about 45% of the total S increase of Western Mediterranean deep-water masses from the 1960s to the late 1990s (Skliris and Lascaratos, 2004). This had to increase, for instance, LIW salinity at its formation site in the eastern Mediterranean. Nile damming was probably a triggering factor for the extinction/drop in abundance of deepsea shrimp off Catalonian coastsThe research was performed within the framework of the MICYT projects BIOMARE (CTM2006-13508-C02-02-MAR) and ANTROMARE (CTM2009-12214-C02-01-MAR)Peer reviewe
Unwanted catches, quota systems and the EU Landing Obligation: An economic and econometric analysis
No full textThe EU Landing Obligation (LO) is inspired by an environmental concern. Bycatches cannot be thrown at sea anymore but brought to land because of many (ethical) and mostly environmental concerns. Discards, in fact, can generate negative impacts on the marine ecosystems and ecological equilibrium, given increased mortality in fish populations and impact on marine biodiversity. The LO has also implications for the organization of the fishery sector (that bears costs of re-organization). The more fishers stick to the rule the better environmental management is guaranteed. The LO generates a trade-off (and potential source of conflict) between fishery markets efficiency and marine environmental protection. The paper, therefore, explores under what conditions markets and environmental protection can "match". The paper takes an economic perspective and provides an economic analysis of (a proposed) discard quota system for regulating unwanted catches in the European fishery sector. Using a simple model, the study evaluates whether and how the regulation designs proper mechanisms that align incentives for different economic agents (e.g. fishers and environmental concerned regulators), which are characterized by different objective functions. The study also provides selected empirical analysis. Results show that fishers choice to comply (or not) with the regulation and the proposed discard quota system, is not only affected by the legal constraint/discard ban per se but also by (1) a set of market conditions that vary day by day and (2) the degree of credible incentive design and implementation of the regulation (and related degree of credible applicability of the fines). An important aspect for the efficient working of the quota system refers to the need to design a mechanism that is also based on experience and evidence. For instance, in the Sicilian case study examined here, the probability to illegally discard UWC varies according to the type of product that is caught. In this perspective, the proposed UWC quota trade has the highest probability to work the higher is the probability (for the fisher) to be fined, the higher are the UWC price and the quantity. On the contrary, the UWC quota trade has the lowest probability to work, the lower is the probability to be fined, the lower is the quantity of UWC and the higher is the price in illegal markets
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
The distribution of megabenthic, invertebrate epifauna in the Balearic Basin (western Mediterranean) between 400 and 2300 m: Environmental gradients influencing assemblages composition and biomass trends
No full textVariations 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
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