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See detailLeczenie osteoporozy--jakie mamy mozliwosci.
Reginster, Jean-Yves ULg

in Polskie Archiwum Medycyny Wewnetrznej (2007), 117(7), 283-4

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See detailLED
Aresti, Alessandro ULg

in AA. VV. (Ed.) 90 parole per novant’anni di invenzioni, scoperte, piccole e grandi rivoluzioni quotidiane (2015)

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See detailLedoux's convection criterion in evolution and asteroseismology of massive stars
Lebreton, Yves; Montalban Iglesias, Josefa ULg; Godart, Mélanie ULg et al

in Communications in Asteroseismology (2009), 158

Saio et al. (2006) have shown that the presence of an intermediate convective zone (ICZ) in post-main sequence models could prevent the propagation of g-modes in the radiative interior and hence avoid the ... [more ▼]

Saio et al. (2006) have shown that the presence of an intermediate convective zone (ICZ) in post-main sequence models could prevent the propagation of g-modes in the radiative interior and hence avoid the corresponding radiative damping. The development of such a convective region highly depends on the structure of the star in the mu-gradient region surrounding the convective core during the main sequence phase. In particular,the development of this ICZ depends on physical processes such as mass loss, overshooting (Chiosi & Maeder 1986, Chiosi et al. 1992, see also Godart et al., 2009) and convective instability criterion (Schwarzschild's or Ledoux's criteria). In this paper we study the consequences of adopting the Ledoux's criterion on the evolution of the convective regions in massive stars (15 and 20 M_{o}), and on the pulsation spectrum of these new B-type variables (also called SPBsg). [less ▲]

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See detailThe LEECH Exoplanet Imaging Survey. Further constraints on the planet architecture of the HR 8799 system (Corrigendum)
Maire, A.-L.; Skemer, A. J.; Hinz, P. M. et al

in Astronomy and Astrophysics (2015), 579

The LBT is an international collaboration among institutions in the United States, Italy and Germany. LBT Corporation partners are: The University of Arizona on behalf of the Arizona university system ... [more ▼]

The LBT is an international collaboration among institutions in the United States, Italy and Germany. LBT Corporation partners are: The University of Arizona on behalf of the Arizona university system; Istituto Nazionale di Astrofisica, Italy; LBT Beteiligungsgesellschaft, Germany, representing the Max-Planck Society, the Astrophysical Institute Potsdam, and Heidelberg University; The Ohio State University, and The Research Corporation, on behalf of The University of Notre Dame, University of Minnesota, and University of Virginia. [less ▲]

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See detailThe LEECH Exoplanet Imaging Survey. Further constraints on the planet architecture of the HR 8799 system
Maire, A.-L.; Skemer, A. J.; Hinz, P. M. et al

in Astronomy and Astrophysics (2015), 576

Context. Astrometric monitoring of directly imaged exoplanets allows the study of their orbital parameters and system architectures. Because most directly imaged planets have long orbital periods (>20 AU ... [more ▼]

Context. Astrometric monitoring of directly imaged exoplanets allows the study of their orbital parameters and system architectures. Because most directly imaged planets have long orbital periods (>20 AU), accurate astrometry is challenging when based on data acquired on timescales of a few years and usually with different instruments. The LMIRCam camera on the Large Binocular Telescope is being used for the LBT Exozodi Exoplanet Common Hunt (LEECH) survey to search for and characterize young and adolescent exoplanets in L' band (3.8 μm), including their system architectures. <BR /> Aims: We first aim to provide a good astrometric calibration of LMIRCam. Then, we derive new astrometry, test the predictions of the orbital model of 8:4:2:1 mean motion resonance proposed for the system, and perform new orbital fitting of the HR 8799 bcde planets. We also present deep limits on a putative fifth planet inside the known planets. <BR /> Methods: We use observations of HR 8799 and the Θ[SUP]1[/SUP] Ori C field obtained during the same run in October 2013. <BR /> Results: We first characterize the distortion of LMIRCam. We determine a platescale and a true north orientation for the images of 10.707 ± 0.012 mas/pix and -0.430 ± 0.076°, respectively. The errors on the platescale and true north orientation translate into astrometric accuracies at a separation of 1'' of 1.1 mas and 1.3 mas, respectively. The measurements for all planets agree within 3σ with a predicted ephemeris. The orbital fitting based on the new astrometric measurements favors an architecture for the planetary system based on 8:4:2:1 mean motion resonance. The detection limits allow us to exclude a fifth planet slightly brighter or more massive than HR 8799 b at the location of the 2:1 resonance with HR 8799 e (~9.5 AU) and about twice as bright as HR 8799 cde at the location of the 3:1 resonance with HR 8799 e (~7.5 AU). The LBT is an international collaboration among institutions in the United States, Italy, and Germany. LBT Corporation partners are: The University of Arizona on behalf of the Arizona university system; Istituto Nazionale di Astrofisica, Italy; LBT Beteiligungsgesellschaft, Germany, representing the Max-Planck Society, the Astrophysical Institute Potsdam, and Heidelberg University; The Ohio State University, and The Research Corporation, on behalf of The University of Notre Dame, University of Minnesota, and University of Virginia. [less ▲]

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See detailThe LEECH Exoplanet Imaging Survey: Characterization of the Coldest Directly Imaged Exoplanet, GJ 504 b, and Evidence for Superstellar Metallicity
Skemer, Andrew J.; Morley, Caroline V.; Zimmerman, Neil T. et al

in Astrophysical Journal (2016), 817

As gas giant planets and brown dwarfs radiate away the residual heat from their formation, they cool through a spectral type transition from L to T, which encompasses the dissipation of cloud opacity and ... [more ▼]

As gas giant planets and brown dwarfs radiate away the residual heat from their formation, they cool through a spectral type transition from L to T, which encompasses the dissipation of cloud opacity and the appearance of strong methane absorption. While there are hundreds of known T-type brown dwarfs, the first generation of directly imaged exoplanets were all L type. Recently, Kuzuhara et al. announced the discovery of GJ 504 b, the first T dwarf exoplanet. GJ 504 b provides a unique opportunity to study the atmosphere of a new type of exoplanet with a ˜500 K temperature that bridges the gap between the first directly imaged planets (˜1000 K) and our own solar system's Jupiter (˜130 K). We observed GJ 504 b in three narrow L-band filters (3.71, 3.88, and 4.00 μm), spanning the red end of the broad methane fundamental absorption feature (3.3 μm) as part of the LBTI Exozodi Exoplanet Common Hunt (LEECH) exoplanet imaging survey. By comparing our new photometry and literature photometry with a grid of custom model atmospheres, we were able to fit GJ 504 b's unusual spectral energy distribution for the first time. We find that GJ 504 b is well fit by models with the following parameters: T[SUB]eff[/SUB] = 544 ± 10 K, g < 600 m s[SUP]-2[/SUP], [M/H] = 0.60 ± 0.12, cloud opacity parameter of f[SUB]sed[/SUB] = 2-5, R = 0.96 ± 0.07 R[SUB]Jup[/SUB], and log(L) = -6.13 ± 0.03 L[SUB]⊙[/SUB], implying a hot start mass of 3-30 M[SUB]jup[/SUB] for a conservative age range of 0.1-6.5 Gyr. Of particular interest, our model fits suggest that GJ 504 b has a superstellar metallicity. Since planet formation can create objects with nonstellar metallicities, while binary star formation cannot, this result suggests that GJ 504 b formed like a planet, not like a binary companion. The LBT is an international collaboration among institutions in the United States, Italy, and Germany. LBT Corporation partners are the University of Arizona on behalf of the Arizona university system; Istituto Nazionale di Astrophisica, Italy; LBT Beteiligungsgesellschaft, Germany, representing the Max-Planck Society, the Astrophysical Institute Potsdam, and Heidelberg University; The Ohio State University, and the Research Corporation, on behalf of the University of Notre Dame, University of Minnesota, and University of Virginia. [less ▲]

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See detailThe LEECH Exoplanet Imaging Survey: Orbit and Component Masses of the Intermediate-age, Late-type Binary NO UMa
Schlieder, Joshua E.; Skemer, Andrew J.; Maire, Anne-Lise et al

in Astrophysical Journal (2016), 818

We present high-resolution Large Binocular Telescope LBTI/LMIRcam images of the spectroscopic and astrometric binary NO UMa obtained as part of the LBT Interferometer Exozodi Exoplanet Common Hunt ... [more ▼]

We present high-resolution Large Binocular Telescope LBTI/LMIRcam images of the spectroscopic and astrometric binary NO UMa obtained as part of the LBT Interferometer Exozodi Exoplanet Common Hunt exoplanet imaging survey. Our H-, K[SUB]s[/SUB]-, and L‧-band observations resolve the system at angular separations <0.″09. The components exhibit significant orbital motion over a span of ∼7 months. We combine our imaging data with archival images, published speckle interferometry measurements, and existing spectroscopic velocity data to solve the full orbital solution and estimate component masses. The masses of the K2.0 ± 0.5 primary and K6.5 ± 0.5 secondary are 0.83 ± 0.02 M[SUB]⊙[/SUB] and 0.64 ± 0.02 M[SUB]⊙[/SUB], respectively. We also derive a system distance of d = 25.87 ± 0.02 pc and revise the Galactic kinematics of NO UMa. Our revised Galactic kinematics confirm NO UMa as a nuclear member of the ∼500 Myr old Ursa Major moving group, and it is thus a mass and age benchmark. We compare the masses of the NO UMa binary components to those predicted by five sets of stellar evolution models at the age of the Ursa Major group. We find excellent agreement between our measured masses and model predictions with little systematic scatter between the models. NO UMa joins the short list of nearby, bright, late-type binaries having known ages and fully characterized orbits. Based on data obtained with the STELLA robotic telescope in Tenerife, an AIP facility jointly operated by AIP and IAC. [less ▲]

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See detailLEECH: A 100 Night Exoplanet Imaging Survey at the LBT
Skemer, Andrew; Apai, Daniel; Bailey, Vanessa et al

in Exploring the Formation and Evolution of Planetary Systems (2014, January 01)

In February 2013, the LEECH (LBTI Exozodi Exoplanet Common Hunt) survey began its 100-night campaign from the Large Binocular Telescope atop Mount Graham in Arizona. LEECH neatly complements other high ... [more ▼]

In February 2013, the LEECH (LBTI Exozodi Exoplanet Common Hunt) survey began its 100-night campaign from the Large Binocular Telescope atop Mount Graham in Arizona. LEECH neatly complements other high-contrast planet imaging efforts by observing stars in L' band (3.8 microns) as opposed to the shorter wavelength near-infrared bands (1-2.3 microns). This part of the spectrum offers deeper mass sensitivity for intermediate age (several hundred Myr-old) systems, since their Jovian-mass planets radiate predominantly in the mid-infrared. In this proceedings, we present the science goals for LEECH and a preliminary contrast curve from some early data. [less ▲]

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See detailLeeman Paul
Tomasovic, Dick ULg

in Moins, Philippe (Ed.) Image par image, le cinéma d’animation en communauté Wallonie-Bruxelles (2001)

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See detailLeer y escribir la literatura científica
Pochet, Bernard ULg; Durand, F.M.

Book published by Fundación universitaria para la investigación, desarrollo, ciencia y cultura San Antonio Abad del Cusco (FUNSAAC) (2016)

Esta obra (traducido por F. M. Durand del francés “Lire et écrire la littérature scientique” el 2012, incluye actualizaciones posteriores) no es una guía de empleo de internet o de diversas ... [more ▼]

Esta obra (traducido por F. M. Durand del francés “Lire et écrire la littérature scientique” el 2012, incluye actualizaciones posteriores) no es una guía de empleo de internet o de diversas herramientas documentales. Es une herramienta de formación científica con un enfoque resueltamente metodológico. Sirve de soporte a los cursos de metodología documental y de literatura científica de Gembloux Agro-Bio Tech (ULg). Puede ampliamente ser utilizado en todas las eseñanzaz y las formaciones que tocan a la literatura científica exactas y aplicadas. Basada en más de veinte años de experiencia y redactado en un estilo simple y directo, esta obra aborda los diferentes aspectos de la búsqueda de informaciones científicas y de la utilización de este información así como los de la producción de artículos publicados en revistas con comité de lectura. El lector por tanto es considerado como lector y usuario de la información científica, y como productor de esta información. Es este enfoque global de la comunicación científica que justifica la elección del título. [less ▲]

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See detailHet Leerdercorpus Nederlands in theorie en in de praktijk
Perrez, Julien ULg; Degand, Liesbeth

Conference (2009, August 24)

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See detailHet Leerdercorpus Nederlands
Degand, Liesbeth; Perrez, Julien ULg

Conference (2003)

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See detailHet Leerdercorpus Nederlands: Perspectieven op de tussentaal van Franstaligen
Degand, Liesbeth; Jansonius, Maarten; Perrez, Julien ULg

Conference (2004)

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See detailLeerdoelen en testformaat : De Europese Talencertificaten : Certificaat Nederlands
Hennen, Karl-Heinz; Vromans, Joseph ULg

Book published by Weiterbildungs-Testsysteme (1999)

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See detailDe leerkrachten en de pedagogisch-didaktische Vernieuwing
de Landsheere, Gilbert ULg

in Doceo (1972), 182

Het ware ongetwijfeld interessant hier ook enkele experimentele demonstraties over weerstanden tegen de vernieuwing te beschrijven. In dit korte bestek is dat echter niet mogelijk. Besluitend wil ik: een ... [more ▼]

Het ware ongetwijfeld interessant hier ook enkele experimentele demonstraties over weerstanden tegen de vernieuwing te beschrijven. In dit korte bestek is dat echter niet mogelijk. Besluitend wil ik: een onvoorwaardelijke waarschuwing laten horen. In onze veranderende samenleving, die zich resoluut en snel verwetenschappelijkt, trachten de opvoedingsdeskundigen soms met een onthutsende goede wil. de school in de vernieuwing in te schakelen. Slecht geïnformeerd, onvoldoende uitgerust met onderzoeksmethodes, slagen zij er niet altijd in een onderscheid te maken tussen de pedagogische mythe en de realiteit, tussen goedkope beweringen en wetenschap. Het getuigt van een ontzettende naïviteit te geloven dat de pedagogisch-didactische wetenschap op alle vragen kan antwoorden, alle problemen kan oplossen. Maar zo maar zonder meer aanvaarden dat de school verder kan evolueren naar haar echte rol in de maatschappij, zonder de beslissingen te doen steunen op strenge studies of de resultaten van de vernieuwingen te onderwerpen aan objectieve evaluaties, getuigt van een niet minder grote naïviteit. Ons land heeft een zeer dringende nood aan een net van onderzoekscentra van hoog niveau. Deze centra moeten zowel op gedetacheerde leerkrachten als academisch geschoolden, inspecteurs en administratieve mensen een beroep doen. Een school in ontwikkeling, deel uitmakend van een samenleving in wording, heeft klaarziende en getrainde geesten nodig. Avonturiers moeten uitgeschakeld worden. [less ▲]

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See detailDe Leeuw van Waterloo. Een trefpunt van verleden, heden en toekomst
Raxhon, Philippe ULg

in Tollebeek, Jo (Ed.) België, een parcours van hennering. Plaatsen van geschiedenis en expansie (2008)

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See detailLEF1-mediated MMP13 gene expression is repressed by SIRT1 in human chondrocytes.
Elayyan, Jinan; Lee, Eun-Jin; Gabay, Odile et al

in FASEB journal : official publication of the Federation of American Societies for Experimental Biology (2017)

Reduced SIRT1 activity and levels during osteoarthritis (OA), promotes gradual loss of cartilage. Loss of cartilage matrix is accompanied by an increase in matrix metalloproteinase (MMP) 13, partially ... [more ▼]

Reduced SIRT1 activity and levels during osteoarthritis (OA), promotes gradual loss of cartilage. Loss of cartilage matrix is accompanied by an increase in matrix metalloproteinase (MMP) 13, partially because of enhanced LEF1 transcriptional activity. In this study, we assessed the role of SIRT1 in LEF1-mediated MMP13 gene expression in human OA chondrocytes. Results showed that MMP13 protein levels and enzymatic activity decreased significantly during SIRT1 overexpression or activation by resveratrol. Conversely, MMP13 gene expression was reduced in chondrocytes transfected with SIRT1 siRNA or treated with nicotinamide (NAM), a sirtuin inhibitor. Chondrocytes challenged with IL-1beta, a cytokine involved in OA pathogenesis, enhanced LEF1 protein levels, and gene expression, resulting in increased MMP13 gene expression; however, overexpression of SIRT1 during IL-1beta challenge impeded LEF1 levels and MMP13 gene expression. Previous reports showed that LEF1 binds to the MMP13 promoter and transactivates its expression, but we observed that SIRT1 repressed LEF1 protein and mRNA expression, ultimately reducing LEF1 transcriptional activity, as judged by luciferase assay. Finally, mouse articular cartilage from Sirt1-/- presented increased LEF1 and MMP13 protein levels, similar to human OA cartilage. Thus, demonstrating for the first time that SIRT1 represses MMP13 in human OA chondrocytes, which appears to be mediated, at least in part, through repression of the transcription factor LEF1, a known modulator of MMP13 gene expression.-Elayyan, J. Lee, E.-J., Gabay, O., Smith, C. A., Qiq, O., Reich, E., Mobasheri, A., Henrotin, Y., Kimber, S. J., Dvir-Ginzberg, M. LEF1-mediated MMP13 gene expression is repressed by SIRT1 in human chondrocytes. [less ▲]

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See detailLefort et Althusser : lecteurs de Machiavel
Mancuso, Eva ULg

Scientific conference (2014, February 20)

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