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See detailThe PLATO 2.0 Mission
Rauer, H.; Catala, C.; Aerts, C. et al

in Experimental Astronomy (2014)

PLATO 2.0 has recently been selected for ESA’s M3 launch opportunity (2022/24). Providing accurate key planet parameters (radius, mass, density and age) in statistical numbers, it addresses fundamental ... [more ▼]

PLATO 2.0 has recently been selected for ESA’s M3 launch opportunity (2022/24). Providing accurate key planet parameters (radius, mass, density and age) in statistical numbers, it addresses fundamental questions such as: How do planetary systems form and evolve? Are there other systems with planets like ours, including potentially habitable planets? The PLATO 2.0 instrument consists of 34 small aperture telescopes (32 with 25 s readout cadence and 2 with 2.5 s candence) providing a wide field-of-view (2232 deg 2) and a large photometric magnitude range (4–16 mag). It focusses on bright (4–11 mag) stars in wide fields to detect and characterize planets down to Earth-size by photometric transits, whose masses can then be determined by ground-based radial-velocity follow-up measurements. Asteroseismology will be performed for these bright stars to obtain highly accurate stellar parameters, including masses and ages. The combination of bright targets and asteroseismology results in high accuracy for the bulk planet parameters: 2 %, 4–10 % and 10 % for planet radii, masses and ages, respectively. The planned baseline observing strategy includes two long pointings (2–3 years) to detect and bulk characterize planets reaching into the habitable zone (HZ) of solar-like stars and an additional step-and-stare phase to cover in total about 50 % of the sky. PLATO 2.0 will observe up to 1,000,000 stars and detect and characterize hundreds of small planets, and thousands of planets in the Neptune to gas giant regime out to the HZ. It will therefore provide the first large-scale catalogue of bulk characterized planets with accurate radii, masses, mean densities and ages. This catalogue will include terrestrial planets at intermediate orbital distances, where surface temperatures are moderate. Coverage of this parameter range with statistical numbers of bulk characterized planets is unique to PLATO 2.0. The PLATO 2.0 catalogue allows us to e.g.: - complete our knowledge of planet diversity for low-mass objects, - correlate the planet mean density-orbital distance distribution with predictions from planet formation theories,- constrain the influence of planet migration and scattering on the architecture of multiple systems, and - specify how planet and system parameters change with host star characteristics, such as type, metallicity and age. The catalogue will allow us to study planets and planetary systems at different evolutionary phases. It will further provide a census for small, low-mass planets. This will serve to identify objects which retained their primordial hydrogen atmosphere and in general the typical characteristics of planets in such low-mass, low-density range. Planets detected by PLATO 2.0 will orbit bright stars and many of them will be targets for future atmosphere spectroscopy exploring their atmosphere. Furthermore, the mission has the potential to detect exomoons, planetary rings, binary and Trojan planets. The planetary science possible with PLATO 2.0 is complemented by its impact on stellar and galactic science via asteroseismology as well as light curves of all kinds of variable stars, together with observations of stellar clusters of different ages. This will allow us to improve stellar models and study stellar activity. A large number of well-known ages from red giant stars will probe the structure and evolution of our Galaxy. Asteroseismic ages of bright stars for different phases of stellar evolution allow calibrating stellar age-rotation relationships. Together with the results of ESA’s Gaia mission, the results of PLATO 2.0 will provide a huge legacy to planetary, stellar and galactic science. [less ▲]

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See detailThe PLATO End-to-End CCD Simulator -- Modelling space-based ultra-high precision CCD photometry for the assessment study of the PLATO Mission
Zima, W.; Arentoft, T.; De Ridder, J. et al

in Astronomische Nachrichten (2010, October 09), 331(9-10),

The PLATO satellite mission project is a next generation ESA Cosmic Vision satellite project dedicated to the detection of exo-planets and to asteroseismology of their host-stars using ultra-high ... [more ▼]

The PLATO satellite mission project is a next generation ESA Cosmic Vision satellite project dedicated to the detection of exo-planets and to asteroseismology of their host-stars using ultra-high precision photometry. The main goal of the PLATO mission is to provide a full statistical analysis of exo-planetary systems around stars that are bright and close enough for detailed follow-up studies. Many aspects concerning the design trade-off of a space-based instrument and its performance can best be tackled through realistic simulations of the expected observations. The complex interplay of various noise sources in the course of the observations made such simulations an indispensable part of the assessment study of the PLATO Payload Consortium. We created an end-to-end CCD simulation software-tool, dubbed PLATOSim, which simulates photometric time-series of CCD images by including realistic models of the CCD and its electronics, the telescope optics, the stellar field, the pointing uncertainty of the satellite (or Attitude Control System [ACS] jitter), and all important natural noise sources. The main questions that were addressed with this simulator were the noise properties of different photometric algorithms, the selection of the optical design, the allowable jitter amplitude, and the expected noise budget of light-curves as a function of the stellar magnitude for different parameter conditions. The results of our simulations showed that the proposed multi-telescope concept of PLATO can fulfil the defined scientific goal of measuring more than 20000 cool dwarfs brighter than mV =11 with a precision better than 27 ppm/h which is essential for the study of earth-like exo-planetary systems using the transit method. [less ▲]

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See detailThe PLATO Simulator: modelling of high-precision high-cadence space-based imaging
Marcos-Arenal, P.; Zima, W.; De Ridder, J. et al

in Astronomy and Astrophysics (2014)

Many aspects of the design trade-off of a space-based instrument and its performance can best be tackled through simulations of the expected observations. The complex interplay of various noise sources in ... [more ▼]

Many aspects of the design trade-off of a space-based instrument and its performance can best be tackled through simulations of the expected observations. The complex interplay of various noise sources in the course of the observations make such simulations an indispensable part of the assessment and design study of any space-based mission. We present a formalism to model and simulate photometric time series of CCD images by including models of the CCD and its electronics, the telescope optics, the stellar field, the jitter movements of the spacecraft, and all important natural noise sources. This formalism has been implemented in a versatile end-to-end simulation software tool, called PLATO Simulator, specifically designed for the PLATO space mission to be operated from L2, but easily adaptable to similar types of missions. We provide a detailed description of several noise sources and discuss their properties, in connection with the optical design, the allowable level of jitter, the quantum efficiency of the detectors, etc. The expected overall noise budget of generated light curves is computed as a function of the stellar magnitude, for different sets of input parameters describing the instrument properties. The simulator is offered to the scientific community for future use. [less ▲]

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See detailPlaton néokantien
Dewalque, Arnaud ULg

Book published by Vrin (in press)

Recueil de textes des principaux philosophes néokantiens sur la théorie platonicienne des Idées (R. H. Lotze, H. Cohen, P. Natorp, W. Windelband, E. Lask, B. Bauch, R. Hönigswald).

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See detailPlaton: le Politique, introduction, traduction et commentaire
Dixsaut, Monique; El Murr, Dimitri; Gavray, Marc-Antoine ULg et al

Book published by Vrin (in press)

Nouvelle traduction commentée et annotée du Politique de Platon

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See detailPlatonisme et néoplatonisme antique
Gavray, Marc-Antoine ULg

in Touati, Houari (Ed.) Encyclopédie de l'humanisme méditerranéen (2014)

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See detailPlatyhypnidium mutatum, a mysterious new moss from Germany
Ochyra, R.; Vanderpoorten, Alain ULg

in Journal of Bryology (1999), 21

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See detailPlatypsyllus castoris Ritsema, 1869 (Coleoptera, Leptinidae), espèce nouvelle pour la faune de Belgique
Libois, Roland ULg

in Bulletin de la Société Royale Belge d'Entomologie = Bulletin van de Koninklijke Belgische Vereniging voor Entomologie (2000), 136(1), 30-31

This paper reports for the first time, the presence of Platypsyllus castoris Rits. in Belgium. The insects were collected on a road killed European beaver found in Anseremme (Dinant) in December 1999 ... [more ▼]

This paper reports for the first time, the presence of Platypsyllus castoris Rits. in Belgium. The insects were collected on a road killed European beaver found in Anseremme (Dinant) in December 1999. This beaver is one of those that were recently illegaly reintroduced in various parts of southern Belgium. [less ▲]

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See detailPlausible values : how to deal with their limitations
Monseur, Christian ULg; Adams, Ray

in Journal of Applied Measurement (2009), 10(3),

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See detailPlay it again, Pinocchio
Curreri, Luciano ULg

in Le avventure di Pinocchio : Storia di un burattino (2002)

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See detailPlay it again, Pinocchio : Pinocchiate, racconti d'Italia, paradigmi
Curreri, Luciano ULg

Book published by Moretti & Vitali (in press)

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See detailA Play of Significance: Roy Williams's Days of Significance and the Question of Labels
Ledent, Bénédicte ULg

in Collier, Gordon; Delrez, Marc; Fuchs, Anne (Eds.) et al Engaging with Literature of Commitment (vol. 2): The Worldly Scholar (2012)

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See detailPlazma urea-N koncentracio és a vemhesülés közötti összefüggés vizsgalata egy holstein-fris tehenészetben
Szenci, O; Simonsen, E.I; Karen, A et al

in Proceeding of effect of plasma urea-N concentration on fertility in a Holstein-friesian dairy herd (2002, October 10)

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See detailPLE for extraction of dioxins in animal feed and ingredients
Focant, Jean-François ULg; Scholl, Georges ULg; De Pauw, Edwin ULg et al

in Organohalogen Compounds (2010, September), 72

Within the entire complex procedure required to measure dioxins and related compounds in biological matrices, the extraction step is often seen as a well controlled step. Although maybe true for many ... [more ▼]

Within the entire complex procedure required to measure dioxins and related compounds in biological matrices, the extraction step is often seen as a well controlled step. Although maybe true for many human and food-related matrices, the situation is very different for animal feed and feed ingredients. Specific European guidelines (e.g. Commission Directive 2006/13/EC, Commission Regulation (EC) No 152/2009) exist for animal feed but only list general requirements for the various stages of the procedure. The liberty is left to laboratories to select, for example, the tools used for the extraction steps. This has the advantage to allow ‘in-house’ methods to be used, as long as they satisfy with all the requirements of the EU Regulation. In that context, it is foreseen that the European Committee for Standardization (CEN) will soon propose a standard for the determination of PCDD/Fs and PCBs in animal feed that would be the reference method to be used to solve potential issues in case of dispute over results reported from different laboratories. A major point of concern is that it has been reported earlier1 that most commonly accepted extraction procedure can conduct to significantly different results for the extraction of dioxins and related compounds in feed and feed additives such as mineral clays and various oxides. Several non-instrumental and instrumental automated approaches are available for extraction. Soxhlet extractors have long been the most used tools for non-instrumental extraction of solids. They have proven to be very efficient but some limitations encouraged the development of other approaches based on instrumental techniques. For feed extraction, pressurized liquid extraction (PLE) (also branded as accelerated solvent extraction ASE®) is the technique of choice for high sample throughput. This study reports on the investigation of the use of various solvent mixtures, extraction temperatures, and instruments (parallel PLE, sequential ASE®) for the extraction of 17 PCDD/Fs and 12 dioxin-like PCBs in mineral clay, bovine feed, fish meal, and in-house quality control animal compound feed. [less ▲]

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See detailPLE for Extraction of Dioxins in Animal Feed and Ingredients
Focant, Jean-François ULg

Scientific conference (2010, April)

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See detailA Plea to Bridge the Gap between Antifungals and the Management of Onychomycosis
ARRESE ESTRADA, Jorge ULg; Pierard-Franchimont, Claudine ULg; Pierard, Gérald ULg

in American Journal of Clinical Dermatology (2001), 2(5), 281-4

Onychomycosis represents a stubborn problem for the clinician facing up to the realities of antifungal treatments. There are obvious discrepancies between data given by in vitro antifungal testings ... [more ▼]

Onychomycosis represents a stubborn problem for the clinician facing up to the realities of antifungal treatments. There are obvious discrepancies between data given by in vitro antifungal testings, pharmacodynamics and pharmacokinetics, and those gathered from clinical experience. This critical review is an attempt at bridging the gap between in vitro and in vivo information about oral antifungals that aim to treat onychomycoses. Common sense shows that the in vitro concept of fungicidy cannot be simply extrapolated into clinical practice. Indeed, chlamidoconidia and arthroconidia present in vivo are much more resistant to antifungals than hyphae. Corneofungimetry may be a realistic bioassay in predicting antifungal activity in human infections. Boosting hyphae growth from conidia while taking antifungals is a new and appealing treatment modality that deserves controlled study. [less ▲]

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See detailPlease Doctor, Resist NOTES!
DETRY, Olivier ULg

in Annals of Surgery (2011), 254(5), 839-840

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