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See detailMiddle Miocene climate and vegetation model reconstructions and their validation with the NECLIME database
François, Louis ULg; Henrot, Alexandra-Jane ULg; Utescher, Torsten et al

in Geophys. Res. Abstracts (2014), 16

The NECLIME database gathers data of the fossil flora recorded at many localities around the world at different times of the Miocene. François et al. (Palaeogeography, Palaeoclimatology, Palaeoecology ... [more ▼]

The NECLIME database gathers data of the fossil flora recorded at many localities around the world at different times of the Miocene. François et al. (Palaeogeography, Palaeoclimatology, Palaeoecology, 304, 359–378, 2011) have presented a new method for evaluating palaeoclimate model simulations from such fossil floras. In this method, palaeovegetation is simulated from climate model outputs, using a dynamic vegetation model. Model vegetation reconstruction is then compared to the vegetation cover indicated by the fossil flora record at the various localities, using a common classification of plant functional types (PFTs) in the data and the model. Here, we apply this method to test several published Middle Miocene climate simulations conducted with General Circulation Models of different complexity: (a) Planet Simulator, (b) FOAM-LMDZ4, (c) MPI-ESM, (d) CCSM3.0 and (4) CESM1.0. Corresponding palaeovegetation distributions are simulated with the CARAIB dynamic vegetation model, in which an upgraded vegetation classification involving 26 PFTs has been imple- mented. The NECLIME palaeoflora data from 154 localities distributed worldwide have been translated in terms of the presence/absence of these PFTs. A comparison of models and data is then undertaken globally and in selected regions of the world, using all available localities. The level of agreement varies among models, among PFTs and among regions. For instance, some models are able to produce tropical and subtropical PFTs in Europe consistently with the data, but the agreement for these PFTs may be much poorer in other parts of the world, such as in northeastern Eurasia. [less ▲]

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See detailMiddle Miocene climate and vegetation modelling with PLASIM and CARAIB
Henrot, Alexandra ULg; François, Louis ULg; Favre, Eric ULg et al

Conference (2009, April 21)

In a long-term climatic cooling trend, the Middle Miocene represents one of the last warm periods of the Neogene, culminating with the Miocene Climatic Optimum, MCO (17-15 My). Palynological studies ... [more ▼]

In a long-term climatic cooling trend, the Middle Miocene represents one of the last warm periods of the Neogene, culminating with the Miocene Climatic Optimum, MCO (17-15 My). Palynological studies suggest that the warmer climatic conditions prevailing during the MCO allowed warm forests to expand poleward of the subtropical zone, with evergreen forests proliferating in North America and Europe (Jimenez-Moreno and Suc, 2007, Palaeogeogr. Palaeoclimatol. Palaeoecol. 253: 208-225). In this work, we used the Planet Simulator (Fraedrich et al., 2005, Meteorol. Z. 14: 299-304 and 305-314), an Earth system model of intermediate complexity, to carry out several simulation experiments, where we have assessed the effects of the absence of ice on the continents, the opening of the Central American and Eastern Tethys seaways, the lowering of the topography on land and the effect of various atmospheric CO2 concentrations, in agreement with the values reported in the litterature. We then produced several vegetation distributions, using the dynamic vegetation model CARAIB (Galy et al., 2008, Quat. Sci. Rev. 27: 1396-1409), to analyse if the climatic forcings considered are sufficient to explain the expansion of warmer forest types to higher latitudes. Our results indicate that an increase of atmospheric CO2 concentration, higher than the present-day one, is necessary to allow subtropical forest types to expand poleward. This result agrees with recent paleo-atmospheric CO2 reconstruction from stomatal frequency analysis, which suggests 500 ppmv of CO2 during the MCO. However, the required warming may be due to processes not considered in our setup (e.g. full oceanic circulation or other greenhouse gases). [less ▲]

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See detailMiddle Miocene climate and vegetation models and their validation with proxy data
Henrot, Alexandra-Jane ULg; Utescher, T.; Erdei, B. et al

in Palaeogeography, Palaeoclimatology, Palaeoecology (2016)

The Miocene is a relatively recent epoch of the Earth's history with warmer climate than today, particularly during the middle Miocene Climatic Optimum (MMCO, approximately 17-15Ma). Although the cause of ... [more ▼]

The Miocene is a relatively recent epoch of the Earth's history with warmer climate than today, particularly during the middle Miocene Climatic Optimum (MMCO, approximately 17-15Ma). Although the cause of the warming is probably not only attributable to CO2, but also to changes in orography and configuration of ocean gateways, this time interval represents an ideal case study to test the ability of climate models to simulate warm climates comparable to those that the Earth may experience in the near future. However, even with higher than present-day CO2 concentrations, the MMCO warming inferred from terrestrial proxy data has been difficult to reproduce in climate models.Since fossil flora do not provide direct information on climate, but on flora and vegetation, climate model results are generally compared to climate reconstructions obtained from the fossil flora. In this study, we apply an alternative method by simulating palaeovegetation from the outputs of the climate model, using a dynamic vegetation model. Model vegetation reconstruction can then be compared to the vegetation cover indicated by the fossil flora record at the various localities, provided that a common classification of plant functional types (PFTs) is used for the data and the model. Here, we reconstruct the vegetation of the middle Miocene with the global dynamic vegetation model CARAIB, using the climatologies derived from five atmospheric general circulation models. The reliability of the simulations is examined on a presence/absence basis of PFTs by comparison of vegetation reconstructions to palaeoflora data recorded in the Northern Hemisphere and the Tropics.This comparison provides an overall agreement around 60% between model and data, when all sites and tree types are considered. Three model simulations out of five show to be better at predicting the absence than the presence. The presence of warm-temperate mixed forests in the middle latitudes, dominated by broadleaved deciduous warm temperate and subtropical trees is generally well reproduced in CARAIB simulations. However, poor agreement is obtained for the presence of tropical PFTs out of the Tropics and for warm PFTs at latitudes northward of 50°N, where climate models remain too cold to produce assemblages of trees consistent with the data. Nevertheless, the model-data comparison performed here highlights several mismatches that could result not only from missing feedbacks in the climate simulations, but also from the data. The results of the likelihood analysis on presence/absence of PFTs illustrate the uncertainties in the PFT classification of the Neogene floral records. The coexistence of some PFTs in the palaeovegetation data is impossible to reproduce in the vegetation model simulations because of the climatic definition of the modern PFTs. This result indicates either a bias in the identification of modern analogues for fossil plant taxa, or a possible evolution of environmental requirements of certain plants. © 2016 Elsevier B.V. [less ▲]

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See detailA Middle Paleolithic site with blade technology at Al Tiwayrat, Qena, Upper Egypt
Vermeersch, Pierre M.; Van Peer, Philip; Rots, Veerle ULg

in Antiquity (2005), 79(305),

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See detailThe Middle to Upper Palaeolithic transition at Trou Al'Wesse: A preliminary overview of stratigraphic units 17 to 15
Miller, Rebecca ULg; Stewart, John; Knul, Monika et al

in Notae Praehistoricae (2015), 35

Units 17, 16 and 15, currently being excavated on the terrace, cover the Middle to Upper Palaeolithic transition at the site of Trou Al'Wesse. These include Late Mousterian layers (Unit 17), an ... [more ▼]

Units 17, 16 and 15, currently being excavated on the terrace, cover the Middle to Upper Palaeolithic transition at the site of Trou Al'Wesse. These include Late Mousterian layers (Unit 17), an archaeologically sterile unit (Unit 16) that contains fauna that will clarify environmental and climatic changes across the transition, and Aurignacian layers (Unit 15). In addition, the discovery of an Aurignacian endscraper on a large blade in previously unexcavated deposits and an undisturbed cave bear den inside the cave suggests that the cave deposits will contain evidence of Mousterian and Aurignacian occupations untouched by the 19th century excavations of Dupont and Fraipont. This paper presents a preliminary overview of the stratigraphic sequence and chronology on the terrace as well as the lithic and faunal assemblages recovered so far. [less ▲]

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See detailThe Middle to Upper Palaeolithic transition in the North-Western European plain
Flas, Damien ULg

Scientific conference (2008)

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See detailThe Middle to Upper Paleolithic transition in Europe: current issues
Flas, Damien ULg

Scientific conference (2010)

Detailed reference viewed: 26 (1 ULg)
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See detailThe Middle-Devonian proto-ovule Runcaria heinzelinii Stockmans 1968
Gerrienne, Philippe ULg; Meyer-Berthaud, B.; Fairon-Demaret, Muriel ULg et al

Conference (2005)

Detailed reference viewed: 45 (0 ULg)
See detailLe Middle-Jazz , l'Ere des Big Bands
Sacré, Robert ULg

Conference given outside the academic context (1986)

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See detailMiddle-Upper Devonian Miospores from the Ghadamis Basin (Tunisia-Libya): systematics and stratigraphy
Loboziak, S; Streel, Maurice ULg

in Review of Palaeobotany and Palynology (1989), 58

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See detailMidsagittal Jaw Movement Analysis for the Scoring of Sleep Apneas and Hypopneas
Senny, Frédéric ULg; Destiné, Jacques ULg; Poirrier, Robert ULg

in IEEE Transactions on Biomedical Engineering (2008), 55(1), 87-95

Given the importance of the detection and classification of sleep apneas and hypopneas (SAHs) in the diagnosis and the characterization of the SAH syndrome, there is a need for a reliable noninvasive ... [more ▼]

Given the importance of the detection and classification of sleep apneas and hypopneas (SAHs) in the diagnosis and the characterization of the SAH syndrome, there is a need for a reliable noninvasive technique measuring respiratory effort. This paper proposes a new method for the scoring of SAHs based on the recording of the midsagittal jaw motion (MJM, mouth opening) and on a dedicated automatic analysis of this signal. Continuous wavelet transform is used to quantize respiratory effort from the jaw motion, to detect salient mandibular movements related to SAHs and to delineate events which are likely to contain the respiratory events. The classification of the delimited events is performed using multilayer perceptrons which were trained and tested on sleep data from 34 recordings. Compared with SAHs scored manually by an expert, the sensitivity and specificity of the detection were 86.1% and 87.4%, respectively. Moreover, the overall classification agreement in the recognition of obstructive, central, and mixed respiratory events between the manual and automatic scorings was 73.1%. The MJM signal is hence a reliable marker of respiratory effort and allows an accurate detection and classification of SAHs. [less ▲]

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See detailMidsagittal Jaw Movements as a Sleep/Wake Marker
Senny, Frédéric ULg; Destiné, Jacques ULg; Poirrier, Robert ULg

in IEEE Transactions on Biomedical Engineering (2009), 56(2), 303-309

The seriousness of the obstructive sleep apnea/hypopnea syndrome is measured by the apnea-hypopnea index (AHI), the number of sleep apneas and hypopneas over the total sleep time (TST). Cardiorespiratory ... [more ▼]

The seriousness of the obstructive sleep apnea/hypopnea syndrome is measured by the apnea-hypopnea index (AHI), the number of sleep apneas and hypopneas over the total sleep time (TST). Cardiorespiratory signals are used to detect respiratory events while the TST is usually assessed by the analysis of electroencephalogram traces in polysomnography (PSG) or wrist actigraphy trace in portable monitoring. This paper presents a sleep/wake automatic detector that relies on a wavelet-based complexity measure of the midsagittal jaw movement signal and multilayer perceptrons. In all, 63 recordings were used to train and test the method, while 38 recordings constituted an independent evaluation set for which the sensitivity, the specificity, and the global agreement of sleep recognition, respectively, reached 85.1%, 76.4%, and 82.9%, compared with the PSG data. The AHI computed automatically and only from the jaw movement analysis was significantly improved (p < 0.0001 ) when considering this sleep/wake detector. Moreover, a sensitivity of 88.6% and a specificity of 83.6% were found for the diagnosis of the sleep apnea syndrome according to a threshold of 15. Thus, the jaw movement signal is reasonably accurate in separating sleep from wake, and, in addition to its ability to score respiratory events, is a valuable signal for portable monitoring. [less ▲]

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See detailMidterm clinical outcome following Edwards SAPIEN or Medtronic Corevalve transcatheter aortic valve implantation (TAVI): Results of the Belgian TAVI registry.
Collas, Valerie M.; Dubois, Christophe ULg; LEGRAND, Victor ULg et al

in Catheterization and cardiovascular interventions : official journal of the Society for Cardiac Angiography & Interventions (2015), 86(3), 528-35

OBJECTIVE: To assess midterm (3 years) clinical outcomes of transcatheter aortic valve implantation (TAVI) in Belgium using the Edwards SAPIEN valve or the Medtronic CoreValve transcatheter heart valve ... [more ▼]

OBJECTIVE: To assess midterm (3 years) clinical outcomes of transcatheter aortic valve implantation (TAVI) in Belgium using the Edwards SAPIEN valve or the Medtronic CoreValve transcatheter heart valve (THV). BACKGROUND: Medium and long term follow-up data of both THVs are still relatively scarce, although of great clinical relevance for a relatively new but rapidly expanding treatment modality. Therefore, reporting mid- and long term clinical outcome data, coming from large "real world" national registries, remains contributive. METHODS: Between December 2007 and March 2012, 861 "real world" patients who were not candidates for surgical aortic valve replacement as decided by the local heart teams, underwent TAVI at 23 sites. Eleven sites exclusively used SAPIEN THV (n = 460), while 12 exclusively used CoreValve THV (n = 401). Differences in clinical outcomes by valve system were assessed, according to access route and baseline EuroSCORE risk profile (<10%: low, 10-20%: intermediate and >20%: high risk). RESULTS: Overall cumulative survival at 3 years was 51% for SAPIEN vs. 60% for CoreValve (P = 0.021). In transfemorally treated patients, SAPIEN and CoreValve had similar survival at 3 years for each of the baseline EuroSCORE cohorts (low risk: 72% vs. 76%, P = 0.45; intermediate risk: 62% vs. 59%, P = 0.94; high risk: 48% vs. 53%, P = 0.65). CONCLUSION: Cumulative midterm 3 year survival after transfemoral TAVI in "real world" patients refused for surgery with similar baseline EuroSCORE risk profile is not different between SAPIEN or CoreValve. [less ▲]

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