Marin Kasimir ou l’art des passages

in Henrion, Pierre (Ed.) Marin Kasimir (2005)

Un panorama et une analyse de l'oeuvre de Marin Kasimir, artiste d'origine autrichienne vivant et travaillant à Bruxelles, dont les images panoramiques, disposées dans des caissons lumineux, ornent ... [more ▼]

Un panorama et une analyse de l'oeuvre de Marin Kasimir, artiste d'origine autrichienne vivant et travaillant à Bruxelles, dont les images panoramiques, disposées dans des caissons lumineux, ornent intérieurs d'immeubles et lieux publics dans de nombreuses grandes villes européennes. [less ▲]

Marine clay minerals, deep circulation and climate

in De Vernal, Anne; Hillaire-Marcel, Claude (Eds.) Proxies in Late Cenozoic Paleoceanography (2007)

Marine mammal selenium linked mercury detoxifaction processes

Poster (2002, May 13)

New results confirm earlier findings on the importance of tiemannite acumulation on speciation and inter-tissue relationships. It is hardly surprising that, as opposed to what was concluded earlier, major ... [more ▼]

New results confirm earlier findings on the importance of tiemannite acumulation on speciation and inter-tissue relationships. It is hardly surprising that, as opposed to what was concluded earlier, major inter-regional differences in Hg accumulation can be demonstrated when comparing several populations of harbour porpoise on an age corrected basis. Important inter-species differences, probably depending on prey choice, are found, even after correction for "relative age". Regional differences are more important than the inter-species variability, at least within both classically described sub-orders of cetaceans. Based on actual estimates of MeHg exposure and tissue concentrations of Hg and MeHg in harbour porpoise from the Southern North Sea, Hg detoxification through precipitation of tiemannite is evaluated to neutralise on average 12% of the overall MeHg intake at age 7. Based on the idea of a 3 fold excess in toxicity of mercury over selenium and a 5 to 15 molar concentration excess of selenium over Hg in fish, Hg seems to play the major part in the mutual detoxification. The formation of tiemannite was previously described as resulting from a two-step accumulation mechanism appearing at a threshold level of Hg 100 g/g fw in liver. The reaching of an equimolar Hg to Se ratio can, however, be fully explained by the gradual increase of tiemannite levels in liver only. The new view is that molar Hg to Se hepatic ratios go towards equimolarity along with the slow nature of the tiemannite detoxification process, with tiemannite gradually taking the upper hand over MeHg, IHg2+ and a surplus of "free" selenium with the increase of the total Hg load. [less ▲]

Marine mammals from the North Sea: Approach of their feeding ecology through stable isotope and cadmium measurements

Poster (2000)

The fertile waters of the North Sea represent one major life site for at least three different marine mammal species: the harbour porpoise, Phocoena phocoena , the harbour seal, Phoca vitulina, and the ... [more ▼]

The fertile waters of the North Sea represent one major life site for at least three different marine mammal species: the harbour porpoise, Phocoena phocoena , the harbour seal, Phoca vitulina, and the white-beaked dolphin, Lagenorhynchus albirostris. More occasionally, oceanic species such as the white-sided dolphin Lagenorhynchus acutus, the sperm whale Physeter macrocephalus or the fin whale Balaenoptera physalus can be sighted or found stranded. Very few data dealing with marine mammal diet in the North Sea are available. In order to contribute to the feeding ecology of these North Sea marine mammals, Cd as well as 15N and 13C measurements have been performed in their tissues. Sperm whales and white-sided dolphins display high renal Cd levels (258 µg.g-1 and 88 µg.g-1 dry weight respectively). Mean Cd concentrations measured in harbour porpoise, harbour seal, white beaked dolphin and fin whale kidneys remain low (mean: 5, 0.9, 0.5 and 4 µg.g-1 respectively). However, some adult porpoises display renal Cd concentrations higher than 10 µg.g-1. Mean 13C measured in the muscles of sperm whales, fin whales and white-sided dolphins are more negative compared to harbour porpoise, harbour seal or white-beaked dolphin mean value. Cd contaminated porpoises display significant lower muscle 13C than other porpoises. Both low d13C and high Cd levels suggest a greater reliance of white-sided dolphins, sperm whales on oceanic cephalopods. It appears that some harbour porpoises can also feed on oceanic squids suggesting dynamic interactions between the North Sea and the North Atlantic porpoise populations. [less ▲]

Marine mammals from the southern North Sea: feeding ecology data from delta C-13 and delta N-15 measurements

in Marine Ecology. Progress Series (2003), 263

The harbour porpoise Phocoena phocoena, grey seal Halichoerus grypus, harbour seal Phoca vitulina and white-beaked dolphin Lagenorhynchus albirostris are regularly found stranded along southern North Sea ... [more ▼]

The harbour porpoise Phocoena phocoena, grey seal Halichoerus grypus, harbour seal Phoca vitulina and white-beaked dolphin Lagenorhynchus albirostris are regularly found stranded along southern North Sea coasts. Occasionally, offshore species such as the fin whale Balaenoptera physalus, the white-sided dolphin L. acutus and the sperm whale Physeter macrocephalus are also found stranded. In order to trace their diet, we measured delta(13)C and delta(15)N in their muscles as well as in 49 invertebrate and fish species collected from the southern North Sea. The delta(15)N data indicate that the harbour seal, grey seal and white-beaked dolphin occupy the highest trophic position, along with ichtyophageous fishes such as the cod Gadus morhua (mean muscle values of 18.7, 17.9, 18.8 and 19.2parts per thousand respectively). The harbour porpoise occupies a slightly lower trophic position (mean delta(15)N value of 16.2parts per thousand), reflecting a higher amount of zooplanktivorous fishes in its diet (mean delta(15)N of 14.7parts per thousand); 2 suckling harbour porpoises displayed a significant delta(15)N enrichment of 2.2parts per thousand compared to adult females. Adult females are delta(15)N-enriched compared to adult male harbour porpoises. Fin whales, sperm whales and white-sided dolphins are C-13-depleted compared to southern North Sea particulate organic matter and species, suggesting that despite regular sightings, they do not feed within the southern North Sea area. [less ▲]

Marine predators as sentinels for our oceans and human health

Conference (2011, November 08)

“During the course of the 20th century, the planet became and is now chemically different from any previous time”. (1) Organic and inorganic chemicals occur in greater abundance because of human activity ... [more ▼]

“During the course of the 20th century, the planet became and is now chemically different from any previous time”. (1) Organic and inorganic chemicals occur in greater abundance because of human activity and end up in the ocean. As more humans inhabit coastal regions, question arises about the health of our oceans. Marine vertebrates such as marine fish, turtles, birds and mammals are used to get early warning about negative trends and impact linked to anthropogenic activities. Such organisms are qualified as sentinel species (2). In turn, sentinels will permit us to better characterize and potentially manage negative impacts on human and animal health associated with our oceans. Marine predators including marine mammals and birds can present elevated concentrations of these organic and inorganic chemicals in their tissues, due to their high position in the trophic chain, their life span, and their fat store in which lipophilic chemicals accumulate. Humans and marine predators share common routes of exposures such as (1) the maternal transfer through placenta and milk and (2) trophic transfer through ingestion of marine fish and shellfish. Furthermore, some human population rely on marine mammal consumption for subsistence. Marine predators offer a snapshot of ocean health that could potentially impact human health. In the hope that this paper will stimulate the research much needed for assessing ocean health in the context of a rapidly changing environment, we provide here a review of (i) levels and trends of contaminants and relationships with biotic and abiotic factors, (ii) toxicological effects and (iii) spatial and geographical trends in tissues of marine predators. We conclude this communication by presenting several necessary perspectives such a more thorough follow of organic and inorganic pollutants in the marine environment including the use of isotopic tracers to assess the local versus global aspects of marine pollution. (1) Reddy, C. M., Stegeman, J. J. & Hahn, M. E. in Oceans and human Health (eds P.J. Walsh et al.) 121-144 (Academic Press, 2008). (2) Bossart G.D. (2011). Vet. Path. 48:676-690. [less ▲]

Marine vertebrate remains from the Toarcian-Aalenian succession of southern Beaujolais, Rhône, France

in Geological Magazine (in press)

A previously undocumented marine vertebrate fauna comprising ichthyosaur, plesiosaur, marine crocodilian and fish remains from the Toarcian-Aalenian succession at Lafarge quarry, southern Beaujolais ... [more ▼]

A previously undocumented marine vertebrate fauna comprising ichthyosaur, plesiosaur, marine crocodilian and fish remains from the Toarcian-Aalenian succession at Lafarge quarry, southern Beaujolais, Rhône, France is described on the basis of both historical collections and new discoveries. The taxonomic composition of the Lafarge quarry marine vertebrate assemblage highlights its cosmopolitan nature and strong relationships with taxa known from elsewhere in Europe. Several groups are recorded for the first time in the Toarcian-Aalenian succession of France, implying new palaeobiogeographic interpretations, and prompting discussion of marine amniote diversity during this interval. [less ▲]

Mario Vargas Llosa, l'éternel révolté

in Revue des Questions Scientifiques (2011), 182(1-2), 147-153

Die Marionettentheaterkompanie "Carlo Colla e Figli"

in Das Andere Theater (2011), 21(79), 16-19

Mariposas de Madrid : Los narradores italianos y la guerra civil española

Book published by Prensas Universitarias de Zaragoza (2009)