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See detailIce-sheet mass balance and climate change
Hanna, E.; Navarro, F.; Pattyn, F. et al

in Nature (2013), 498

Since the 2007 Intergovernmental Panel on Climate Change Fourth Assessment Report, new observations of ice-sheet mass balance and improved computer simulations of ice-sheet response to continuing climate ... [more ▼]

Since the 2007 Intergovernmental Panel on Climate Change Fourth Assessment Report, new observations of ice-sheet mass balance and improved computer simulations of ice-sheet response to continuing climate change have been published. Whereas Greenland is losing ice mass at an increasing pace, current Antarctic ice loss is likely to be less than some recently published estimates. It remains unclear whether East Antarctica has been gaining or losing ice mass over the past 20 years, and uncertainties in ice-mass change for West Antarctica and the Antarctic Peninsula remain large. We discuss the past six years of progress and examine the key problems that remain. [less ▲]

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See detailIch könnte jetzt nicht zeichnen […] und bin nie ein größerer Maler gewesen“ – Passivität und Schöpferkraft der „Künstler ohne Werk
Pontzen, Alexandra ULg

in Busch, Kathrin; Draxler, Helmut (Eds.) Theorien der Passivität (2013)

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See detailIchthyosaurs from the French Rhaetian indicate a severe turnover across the Triassic–Jurassic boundary
Fischer, Valentin ULg; Cappetta, Henri; Vincent, Peggy et al

in Naturwissenschaften (Die) (2014), 101

Mesozoic marine reptiles went through a severe turnover near the end of the Triassic. Notably, an important extinction event affected ichthyosaurs, sweeping a large part of the group. This crisis is ... [more ▼]

Mesozoic marine reptiles went through a severe turnover near the end of the Triassic. Notably, an important extinction event affected ichthyosaurs, sweeping a large part of the group. This crisis is, however, obscured by an extremely poor fossil record and is regarded as protracted over the entire Norian–earliest Jurassic interval, for the lack of a more precise scenario. The iconic whale-sized shastasaurid ichthyosaurs are regarded as early victims of this turnover, disappearing by the middle Norian. Here we evaluate the pattern of this turnover among ichthyosaurs by analysing the faunal record of two Rhaetian localities. One locality is Autun, eastern France; we rediscovered in this material the holotypes or partial ‘type’ series of Rachitrema pellati, Actiosaurus gaudryi, Ichthyosaurus rheticus, Ichthyosaurus carinatus and Plesiosaurus bibractensis; a revised taxonomic scheme is proposed. The second assemblage comes from a new locality: Cuers, southeastern France. Both these assemblages provide several lines of evidence for the presence of shastasaurid-like ichthyosaurs in the Rhaetian of Europe. These occurrences suggest that both the demise of shastasaurids and the sudden radiation of neoichthyosaurians occurred within a short time window; this turnover appears not only more abrupt but also more complex than previously postulated and adds a new facet of the end-Triassic mass extinction [less ▲]

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See detailIchthyosaurs from the Jurassic of Skye, Scotland
Brusatte, S. L.; Young, M. T.; Challands, T. J. et al

in Scottish Journal of Geology (2015), 51(1), 4355

Fossils of Mesozoic vertebrates are rare in Scotland, particularly specimens of marine reptiles such as plesiosaurs and ichthyosaurs. We describe a suite of ichthyosaur fossils from the Early to Middle ... [more ▼]

Fossils of Mesozoic vertebrates are rare in Scotland, particularly specimens of marine reptiles such as plesiosaurs and ichthyosaurs. We describe a suite of ichthyosaur fossils from the Early to Middle Jurassic of Skye, which to our knowledge are the first ichthyosaurs from Scotland to be described and figured in detail. These fossils span approximately 30 million years, from the Sinemurian to the Bathonian, and indicate that ichthyosaurs were a major component of Scottish marine faunas during this time. The specimens include isolated teeth that could represent the most northerly known occurrences of the widespread Sinemurian species Ichthyosaurus communis, a characteristic component of the famous Lyme Regis faunas of England, suggesting that such faunas were also present in Scotland during the Early Jurassic. An associated humerus and vertebrae from Toarcian–Bajocian-aged deposits are named as a new genus and species of basal neoichthyosaurian, Dearcmhara shawcrossi. The taxonomic affinities of this taxon, which comes from a critical but poorly sampled interval in the fossil record, suggest that non-ophthalmosaurid neoichthyosaurians dominated European assemblages around the Early–Middle Jurassic boundary, and were later replaced by ophthalmosaurids, whose radiation likely took place outside Europe. Many of these specimens were collected by amateurs and donated to museum collections, a co-operative relationship essential to the preservation of Scotland’s fossil heritage. [less ▲]

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See detailIchtyofaune du bassin du fleuve Mono (Bénin et Togo): diversité, écologie et impacts anthropiques
Lederoun, Djiman ULg

Doctoral thesis (2015)

This study has three main objectives: (1) to obtain an inventory of the ichthyofauna of the Mono River that is as complete as possible; (2) to study the ecology of this ichthyofauna; and (3) to document ... [more ▼]

This study has three main objectives: (1) to obtain an inventory of the ichthyofauna of the Mono River that is as complete as possible; (2) to study the ecology of this ichthyofauna; and (3) to document the impact of fishing on the exploited stocks based on two targeted species. The inventory was made by compiling the literature, by studying collections of museums and of other institutions and by several sampling campaigns, conducted between February 2011 and March 2014. This resulted in an inventory of 91 fish species belonging to 67 genera, 42 families and 14 orders. The Perciformes (31 species), Siluriformes (18), Osteoglossiformes (10), Cypriniformes (9) and Characiformes (9) are the most diverse families in the Mono River Basin. The most species-rich families are the Cichlidae (9 espèces), Cyprinidae (9), Mormyridae (7), Clariidae (7) and Alestidae (6). Twenty-nine species, of which 7 of freshwater and 22 of marine or estuarine origin have been added to the ichtyofauna as known before this study. Nine species present in museum collections and three species only known from the literature have not been collected again. Several taxonomic problems have been encountered. Two of these cases were studied in depth. Foremost, the taxonomic status of Brycinus leuciscus and B. luteus (Alestiidae, Characiformes) was revised based on specimens originating from the complete distribution range of the two nominal species. This allowed us to synonymise the two species, with Brycinus leuciscus as senior synonym. The latter has been erroneously mentioned from the Mono River. Our results, however, confirmed the presence of two phenotypes, i.e. one with and one without a pre-dorsal hump, which was mentioned in the literature as intra-specific variation in B. leuciscus. A comparative study comparing specimens belonging to 'Barbus' nigeriensis (Cyprinidae, Cypriniformes) of the Mono Basin with those originating from the basins of the Volta, the Ogun et the Niger revealed the presence of a new species, described as Barbus "Vandewalle", a Volta Basin endemic. An indentification key of the different families, genera and species from the Mono Basin is presented. For the ecological study, two seasonal sampling campaigns were performed (from December to mid-March and from mid-July to mid-September) in 2012 and 2013 using gill nets of different mesh-size (10, 12, 17, 20 et 22 mm knot to knot). Sampling was performed at 10 sampling sites that were located upstream and downstream of the Adjarala Falls (the site of a planned hydroelectric plant, 100 km upstream of that of Nangbéto) and upstream and downstream of the dam at Nangbéto. Seventeen physico-chemical and environmental variables were taken at these sites. The ordination of the sampling sites in relation to their values for the physico-chemical, environmental variables and to their fish assemblages was studied using a non-linear method: the self organising map (SOM). The samples were scattered in four groups in function of their physico-chemical and environmental variables. The distance to the source, height of the canopy, rocks, coverage of the canopy, altitude, gravel, mud, sand, water velocity and dissolved oxygen were the most discriminating factors for the obtained groups. The zone of the Adjarala, where a new dam will be constructed, differs by its rocky substrate, the velocity of the water and the relatively high amount of dissolved oxygen. For the ichthyofauna, the SOM suggest a structuring in three groups. Our results oppose the tendency to homogeny in the middle course of rivers, which is probably due to the presence of the dam at Nangbéto. A significant correlation was found between the distribution of the species and the physico-chemical and environmental parameters. The distance to the source, altitude, forested river banks, height of the canopy, velocity of the water, conductivity, transparency and pH were the parameters that explained the distribution of the fish community best. The level of disturbance of the ecosystem, which was studied using the Abundance Biomass Comparison (ABC) showed that the zones at and near the dam at Nangbéto were the most stressed. A length-weight and length-length key was designed for the first time for the 37 species that were the most abundant in the catches. This was done in order to improve the quality of the fisheries statistics collected by fisheries officers on the scale of the basin. The analysis of the allometric coefficient b of the length-weight relation showed that the majority of the fishes had an allometric growth. The condition factor calculated in order to estimate the amount of flesh on the fish showed that the environment was heavily disturbed. To conclude, from the results of the study on the impact of the fisheries on targeted species, it became clear that the population of Sarotherodon melanotheron melanotheron is over-exploited at Lake Toho. At Lakes Doukon and Togbadji, on the other hand, an under-exploitation of the population of S. galilaeus galilaeus was observed. The latter illustrates the possibility of sustainable management even in the presence of intensive fishing pressure. As, in this thesis, several cases of anthropogenic impacts were identified, a regular surveillance programme will be paramount in order to preserve the ichthyological diversity of the Mono River Basin. [less ▲]

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See detail"Ici et là" chez les historiens latins
Longrée, Dominique ULg

in Vuillaume, Marcel (Ed.) Ici et maintenant (2008)

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See detailICON FUV Imager
Mende, Stephen; Chou, Cathy; Loicq, Jerôme ULg et al

Conference (2015, April)

A novel design FUV spectrographic imager is currently under construction at UC Berkeley for the payload of the Ionospheric Connection Explorer (ICON). This instrument will image the limb-view atmosphere ... [more ▼]

A novel design FUV spectrographic imager is currently under construction at UC Berkeley for the payload of the Ionospheric Connection Explorer (ICON). This instrument will image the limb-view atmosphere/ionosphere with a FOV of 24x18 degrees (vertical and horizontal) tilted down by 20⁰ and looking in a direction nominally perpendicular to the spacecraft velocity. From the spacecraft altitude (575 km) the view provides coverage from sub-limb up to ~500 km limb tangent height. There is a steering mirror assembly that allows steering the view ±30⁰ with respect to the nominal direction in order to observe the nightglow emissions along the local magnetic meridian. The instrument uses the spectrographic imager principle first used on the IMAGE spacecraft in which several full two-dimensional instantaneous images are formed in specific wavelength bands. One of the two bands on ICON contains the 135.6 nm atomic oxygen emission while the other band covers the N2 LBH emission region near 157 nm. When the imager is viewing the sunlit atmosphere the instrument provides the limb altitude profile of the atmospheric O/N2 ratio. On the night side the instrument observes the 135.6 nm emission that is produced by the recombination of O+ and therefore provides a good proxy for the nighttime ionospheric density. To minimize data downlink, 6 parallel vertical stripe segments will be transmitted to the ground from both channels every 12 seconds. In addition the nighttime 135.6 nm data will be integrated as two dimensional (spacecraft orbit latitude and longitude) maps. One map is projected on a sphere at 300 km altitude while the other map projects at a surface defined by the tangent height of observation from the ICON satellite. Both maps will be integrated with motion compensation to minimize blurring due to the satellite motion. [less ▲]

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See detailIcon with the Virgin Hodegetria
George, Philippe ULg

in Catalogue de l'exposition Byzantium : Faith and Power (1261-1557), p. 252-253. (2004)

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See detailICON: The Ionospheric Connection Explorer - NASA's Next Space Physics and Aeronomy Mission
Immel, T. J.; Mende, S. B.; Heelis, R. A. et al

Conference (2013)

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See detailIcona bizantina detta "Vergine di San Luca" Liegi, Tesoro della Cattedrale
George, Philippe ULg

in Morello, Giovanni (Ed.) Catalogue de l'exposition Libri di Pietra. Mille anni della cattedrale di Ancona tra Oriente e Occidente, sous la direction de Giovanni Morello (1999)

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See detailIcone d'amore: immagini nuziali e ritratti coniugali tra Quattro e Cinquecento
Bugini, Mariaelena ULg

Scientific conference (2010)

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See detailL'icône du visible
Steinmetz, Rudy ULg

in Etudes Phénoménologiques (2000)

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See detailL'icône, ou les visages de l'invisible
Verbeeck, Muriel ULg; MARKOPOLOU, Eleni

in Buyle, Marjan (Ed.) Restaurer l'invisible, Actes des journées d'étude BRK-APROA (2012)

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See detailIconic turn et critique du paradigme langagier
Hagelstein, Maud ULg

in Bulletin d'Analyse Phénoménologique (2016), 12 (2016)(2),

Comment appréhender le problème de la légalité des significations dans le champ non verbal du visuel ? Tel est l’exercice auquel s’essaie le théoricien de l’image allemand Gottfried Boehm, soucieux de ... [more ▼]

Comment appréhender le problème de la légalité des significations dans le champ non verbal du visuel ? Tel est l’exercice auquel s’essaie le théoricien de l’image allemand Gottfried Boehm, soucieux de dégager les principes formels structurant l’émergence de significations dans le domaine du visuel, tout en tenant à distance l’usage de la grammaire prédicative pour la compréhension des images. Sa proposition s’inscrit dans le cadre des débats autour de ce que l’on appelle — dans le domaine de la théorie de l’image actuelle — l’iconic turn (le « tournant iconique » / ikonische Wendung). À bien des égards, l’iconic turn est lié à une réflexion large sur l’héritage de l’iconologie, cette discipline d’interprétation des images inaugurée en 1912 par le théoricien de l’art Aby Warburg (1866-1929), nourrie par la philosophie des formes symboliques de Ernst Cassirer (1874-1945), et systématisée par Erwin Panofsky (1892-1968) dans ses Essais d’iconologie (1939), notamment1. Visant l’interprétation du contenu symbolique des images, la méthode iconologique concevait l’art comme l’un des domaines essentiels de production de sens, une « forme symbolique » privilégiée, pour reprendre la terminologie cassirérienne2. Le célèbre tableau synthétique repris en introduction aux Essais d’iconologie montre comment procède l’iconologie, par dégagement progressif de couches de significations. S’il a construit sa méthode en dialogue avec la philosophie, Panofsky n’a pas pour autant intégré au cahier des charges de l’iconologie l’ambition de dégager systématiquement les principes formels conditionnant la possibilité même de la signification — raison pour laquelle cette discipline n’est pas à proprement parler philosophique. L’iconologie est exégétique ; elle offre les outils nécessaires à une interprétation précise du contenu des œuvres. Table des matières 1. Changement de paradigme : le tournant iconique 2. La différence iconique : une logique des contrastes 3. L’image montre la monstration 4. Un affranchissement relatif Conclusion [less ▲]

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See detailIconic turn et critique du paradigme langagier
Hagelstein, Maud ULg

Conference (2015, May 05)

Je voudrais envisager ici le problème de la légalité des significations dans le champ non-verbal du visuel, tel qu’il est envisagé par un théoricien de l’image allemand actuel (G. Boehm). On pourrait en ... [more ▼]

Je voudrais envisager ici le problème de la légalité des significations dans le champ non-verbal du visuel, tel qu’il est envisagé par un théoricien de l’image allemand actuel (G. Boehm). On pourrait en effet dégager – selon la proposition de Boehm – un principe formel (au moins) qui structure l’émergence de significations dans le domaine du visuel. Boehm ne parle de grammaire à proprement parler que pour s’en écarter (il rejette l’usage de la grammaire prédicative pour la compréhension des images). [less ▲]

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See detailIconic virtues of diagrams. Peirce and ampliative reasoning
Leclercq, Bruno ULg

Conference (2015, September 08)

In his Critic of pure reason, Immanuel Kant notoriously claimed that, being grounded on the forms of sense intuition, arithmetical and geometrical propositions are both synthetic (i.e. informative) and a ... [more ▼]

In his Critic of pure reason, Immanuel Kant notoriously claimed that, being grounded on the forms of sense intuition, arithmetical and geometrical propositions are both synthetic (i.e. informative) and a priori. Bernard Bolzano, followed in this by the logicist movement (from Gottlob Frege to Rudolf Carnap), answered that the generality and necessity of mathematical propositions and proofs can only be grounded on conceptual analysis. Even though, just like Frege, he is one of the fathers of formal logic, Charles Sanders Peirce provides some semiotic reasons to think that Kant was right: diagrams do convey general meanings and provide some knowledge which is necessary yet non-trivial. Unlike logical analysis, visual presentation of concepts in schemas or diagrams helps to explore concepts by stressing some of their “side” features in such a way that new knowledge is gained: « diagrams evolve what was involved » (CP4/86). This is why, according to Kant’s notion of intuitive construction, mathematical inferences are not merely deductive but are inventive and ampliative. My talk aims at identifying some iconic virtues of diagrams which, according to Peirce, explain their epistemic productivity. A first one lies in the “formal” nature of icons, which allows them to express syntactic relations between descriptive (symbols) and demonstrative (indices) components of structured information. On this respect, even algebraic and ideographic expressions are icons exhibiting a general form – a “rheme” – in which places for indices are filled with variables “x” and “y” meaning “any individual”. For this reason, even though they are singular, diagrams are “abstractions” in the sense that they represent relations rather than their terms. Only with this in prospect can a second, and more studied, feature of diagrams matter, namely their two-dimensionality, which helps to exhibit complex relations that cannot be seen on linear linguistic expressions. Finally, a third feature of diagrams lies in their imaginary rather than referential character. Icons connote without denoting, and therefore they can be informational without this information being limited to singular individuals. Furthermore, this non referential character of icons is what makes them open to virtual exploratory manipulations that allow to consider and investigate possibilities which in turn inform us on not obvious properties of the presently visible configuration. [less ▲]

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See detailIconic virtues of diagrams. Peirce on ampliative reasoning
Leclercq, Bruno ULg

in Signata. Annales des Sémiotiques = Annals of Semiotics (2017)

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