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See detailEvaluation of uncertainty sources in the determination of testosterone in urine by calibration-based and isotope dilution quantification using ultra high performance liquid chromatography tandem mass spectrometry
Pitarch-Motellón, Jorge; Roig-Navarro, Antoni F.; Sancho Llopis, Juan V. et al

in Journal of Chromatography A (2017)

Three quantification methodologies, namely calibration with internal standard (Cal-IS, non-weighted), weighted calibration with internal standard (wCal-IS) and isotope pattern deconvolution (IPD) have ... [more ▼]

Three quantification methodologies, namely calibration with internal standard (Cal-IS, non-weighted), weighted calibration with internal standard (wCal-IS) and isotope pattern deconvolution (IPD) have been used for the determination of testosterone in urine by LC-MS/MS. Uncertainty has been calculated and compared for the three methodologies through intra- and inter-laboratory reproducibility assays. IPD showed the best performance for the intra-laboratory reproducibility, with RSD and combined uncertainty values below 4% and 9% respectively. wCal-IS showed similar performance, while Cal-IS where not constant and clearly worse at the lowest concentration assayed (2 ng/mL) reaching RSD values up to 16%. The inter-laboratory assay indicated similar results although wCal-IS RSD (20%) was higher than IPD (10%) and Cal-IS get worse with RSD higher than 40% for the lowest concentration level. Uncertainty budgets calculated for the three procedures revealed that intercept and slope were the most important factors contributing to uncertainty for Cal-IS. The main factors for wCal-IS and IPD were the volumes of sample and/or standard measured. [less ▲]

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See detailLand status of agricultural concessions in Kinshasa (D. R. Congo): Legal framework limitations to Production Incentive.
Masiala Bode, Mabu ULiege; Lebailly, Philippe ULiege; Kinkela Savy Sunda, Charles et al

Conference (2017, March 22)

This article clarifies the land status of agricultural concessions of the Mont-Ngafula council in Kinshasa. This council is particular given that it has a hybrid land status which is both urban and rural ... [more ▼]

This article clarifies the land status of agricultural concessions of the Mont-Ngafula council in Kinshasa. This council is particular given that it has a hybrid land status which is both urban and rural. This therefore entails the application of the two land tenure systems depending on whether the area concerned is urban or rural. The results of this analysis highlights that since the enactment of the 1973 Land Act, access to agricultural land in this region rarely comply with legal procedure; most land occupants rather transact with various individuals who have customary rights over lands (traditional chiefs and customary landowners) instead meeting the competent services. As a matter of fact, from a legal standpoint, most of the occupants simply limit themselves to awarding a provisional occupancy contract, which is just a preparatory step to agricultural concession, the issuance of which appears to be less strenuous as per common practice in the constituency. The fact that land owners limit themselves at the stage of the provisional contract, usually far beyond the officially prescribed deadline, without even launching the application for the concession contract justifies the lack and poor level of development of occupied lands. Meanwhile, the value of these lands increases. The great trust gained by owners from the land administration (through the holding of provisional occupancy contract) and the payment of customary rights enables him/her to keep the funds in serenity and to receive yearly appreciation without an actual agricultural production. Thus, lands status obtained on the basis of this double recognition ensures an apparent land tenure security but does not promote agricultural production. In addition, the Land Act does not include any incentive instruments in this domain, and closer still, mechanisms set out in the law pertaining to the fundamental principles relating to agriculture are not at the verge of being instituted soon, much less the land reform policy initiated by the Congolese Government these past years. [less ▲]

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See detailLes Wallons face au vieillissement
Wiliquet, Muriel ULiege; Voz, Bernard ULiege

Report (2017)

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See detailAdorno, Theodor W., 1903-1969
Hagelstein, Maud ULiege

in Les théoriciens de l'art (2017)

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See detailArtaud, Antonin. 1896-1948
Hagelstein, Maud ULiege

in Les théoriciens de l'art (2017)

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See detailBenjamin, Walter. 1892-1940
Hagelstein, Maud ULiege

in Les théoriciens de l'art (2017)

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See detailBrecht, Bertold. 1898-1956
Hagelstein, Maud ULiege

in Les théoriciens de l'art (2017)

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See detailBataille, Georges. 1897-1962
Hagelstein, Maud ULiege

in Les théoriciens de l'art (2017)

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See detailBurckhardt, Jacob. 1818-1897
Hagelstein, Maud ULiege

in Les théoriciens de l'art (2017)

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See detailCassirer, Ernst. 1874-1945
Hagelstein, Maud ULiege

in Les théoriciens de l'art (2017)

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See detailInvestigation of a heat pump reversible in an organic Rankine cycle and its application in the building sector
Dumont, Olivier ULiege

Doctoral thesis (2017)

This thesis studies the concept of reversible heat pump / organic Rankine cycle (HP/ORC) and its application in the building sector. Chapter one describes this HP/ORC system and its possible applications ... [more ▼]

This thesis studies the concept of reversible heat pump / organic Rankine cycle (HP/ORC) and its application in the building sector. Chapter one describes this HP/ORC system and its possible applications. A tool based on operating maps is developed to determine the feasibility of such a system depending on the operating conditions of a given application. In Chapter two, the reversibility of volumetric machines is studied based on a theoretical comparison followed by experimental results collected on four different compressor/expander technologies. The comparison shows which technology should be used depending on the characteristics of an application. In Chapter three, the design and sizing methodology to optimize the performance of the reversible heat pump /organic Rankine cycle is described. This design and sizing optimisation is performed in the case of the residential application: the reversible HP/ORC system is coupled with a large solar absorber in a building to provide a polyvalent machine able to produce heat or electricity depending on the needs of the building. Steady-state models are then used to predict the annual performance of the system integrated in a building. As the theoretical results are promising in the case of the residential application, a test-rig is built and an experimental campaign is performed in both HP and ORC modes (Chapter four). A global methodology to improve the quality of experimental data is proposed based on two different mathematical tools. The method combines the reconciliation method and the Gaussian Processes sensitivity analysis. A model is calibrated based on experimentation to characterize the performance of the HP/ORC unit with an optimal control and with a wide range of inputs. Chapter five studies the reversible unit in the case of the building application based on advanced dynamic models. The global model combines validated sub-models: the reversible unit, the solar roof, the thermal energy storage, the horizontal ground heat exchanger and the building. An optimal control strategy is developed and presented. A parametric study is performed to observe the performance of the system in a wide range of typologies. The influence of different lights and appliances profiles, building envelopes, integration of batteries, roof tilt angles, locations, storage sizes is developed. Furthermore, a technical and economic comparison with one of the most mature technologies to get a positive energy building, namely photovoltaics panels combined with a heat pump in a passive house, is performed. [less ▲]

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See detailLevel set topology optimization considering damage
Noel, Lise; Duysinx, Pierre ULiege; maute, kurt

in Structural and Multidisciplinary Optimization (2017), 56

This paper provides a level set based topology optimization approach to design structures exhibiting resistance to damage. The geometry of the structures is represented by the level set method. The design ... [more ▼]

This paper provides a level set based topology optimization approach to design structures exhibiting resistance to damage. The geometry of the structures is represented by the level set method. The design domains are discretized by the extended finite element method allowing for fixed non conforming meshes. The mechanical model represents quasi-brittle materials. Undamaged material behavior is assumed linear elastic while a loss of stiffness is introduced through a non-local damage model. Small strains are assumed. The sensitivities are evaluated by an analytical derivation of the discretized governing equations of the system and considering the adjoint approach. As the damage process is irreversible, the structural responses are path-dependent and this dependency is accounted for in the sensitivity analysis. The optimization problems are solved by mathematical programming algorithms, in particular using the GCMMA scheme. The proposed approach is illustrated with two dimensional examples that highlight the influence of degradation on the optimized designs. [less ▲]

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See detailIn Octavo. Des formarts de l'art
Hagelstein, Maud ULiege

Article for general public (2016)

La question du format n'est pas seulement ici l'objet du livre. Ou alors, le lecteur serait en réalité confronté à un objet qui aurait contaminé le regard posé sur lui - au sens positif de la ... [more ▼]

La question du format n'est pas seulement ici l'objet du livre. Ou alors, le lecteur serait en réalité confronté à un objet qui aurait contaminé le regard posé sur lui - au sens positif de la contamination. En effet, le livre "IN OCTAVO" explore lui-même un format alternatif où se mêlent apports théoriques et expériences pratiques (pour autant que ce partage entre théorie et pratique ait un sens : il semble très concrètement discuté par certains contributeurs). Par son rapport à la fois engagé et ludique au format livre, par ses modalités d'organisation, In octavo invente un nouveau genre d'enquête. Que font les formats dans les domaines de l'art, de la science, du traitement de l'information, de la performance, de la muséologie, de ma scène contemporaine ou de la musique ? [less ▲]

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See detailÉvaluation externe du Trade for Development Center
Grega, Pierre; Grega, Natalia; Voz, Bernard ULiege et al

Report (2016)

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See detailGravitational microlensing as a probe for dark matter clumps
Fedorova, E.; Sliusar, V. M.; Zhdanov, V. I. et al

in Monthly Notices of the Royal Astronomical Society (2016), 457(4), 4147-4159

Extended dark matter (DM) substructures may play the role of microlenses in the Milky Way and in extragalactic gravitational lens systems (GLSs).We compare microlensing effects caused by point masses ... [more ▼]

Extended dark matter (DM) substructures may play the role of microlenses in the Milky Way and in extragalactic gravitational lens systems (GLSs).We compare microlensing effects caused by point masses (Schwarzschild lenses) and extended clumps of matter using a simple model for the lens mapping. A superposition of the point mass and the extended clump is also considered. For special choices of the parameters, this model may represent a cusped clump of coldDM, a cored clump of self-interacting darkmatter (SIDM) or an ultra-compact minihalo of DMsurrounding a massive point-like object.We built the resulting micro-amplification curves for various parameters of one clump moving with respect to the source in order to estimate differences between the light curves caused by clumps and by point lenses. The results show that it may be difficult to distinguish between thesemodels. However, some region of the clump parameters can be restricted by considering the high amplification events at the present level of photometric accuracy. Then we estimate the statistical properties of the amplification curves in extragalactic GLSs. For this purpose, an ensemble of amplification curves is generated yielding the autocorrelation functions (ACFs) of the curves for different choices of the system parameters.We find that there can be a significant difference between these ACFs if the clump size is comparable with typical Einstein radii; as a rule, the contribution of clumps makes the ACFs less steep. © 2016 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society. [less ▲]

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See detailThe XXL Survey: XII. Optical spectroscopy of X-ray-selected clusters and the frequency of AGN in superclusters
Koulouridis, E.; Poggianti, B.; Altieri, B. et al

in Astronomy and Astrophysics (2016), 592

Context. This article belongs to the first series of XXL publications. It presents multifibre spectroscopic observations of three 0.55 deg2 fields in the XXL Survey, which were selected on the basis of ... [more ▼]

Context. This article belongs to the first series of XXL publications. It presents multifibre spectroscopic observations of three 0.55 deg2 fields in the XXL Survey, which were selected on the basis of their high density of X-ray-detected clusters. The observations were obtained with the AutoFib2+WYFFOS (AF2) wide-field fibre spectrograph mounted on the 4.2 m William Herschel Telescope. Aims. The paper first describes the scientific rationale, the preparation, the data reduction, and the results of the observations, and then presents a study of active galactic nuclei (AGN) within three superclusters. Methods. To determine the redshift of galaxy clusters and AGN, we assign high priority to a) the brightest cluster galaxies (BCGs), b) the most probable cluster galaxy candidates, and c) the optical counterparts of X-ray point-like sources. We use the outcome of the observations to study the projected (2D) and the spatial (3D) overdensity of AGN in three superclusters. Results. We obtained redshifts for 455 galaxies in total, 56 of which are counterparts of X-ray point-like sources. We were able to determine the redshift of the merging supercluster XLSSC-e, which consists of six individual clusters at z ~ 0.43, and we confirmed the redshift of supercluster XLSSC-d at z ~ 0.3. More importantly, we discovered a new supercluster, XLSSC-f, that comprises three galaxy clusters also at z ~ 0.3. We find a significant 2D overdensity of X-ray point-like sources only around the supercluster XLSSC-f. This result is also supported by the spatial (3D) analysis of XLSSC-f, where we find four AGN with compatible spectroscopic redshifts and possibly one more with compatible photometric redshift. In addition, we find two AGN (3D analysis) at the redshift of XLSSC-e, but no AGN in XLSSC-d. Comparing these findings with the optical galaxy overdensity we conclude that the total number of AGN in the area of the three superclusters significantly exceeds the field expectations. All of the AGN found have luminosities below 7 × 1042 erg s-1. Conclusions. The difference in the AGN frequency between the three superclusters cannot be explained by the present study because of small number statistics. Further analysis of a larger number of superclusters within the 50 deg2 of the XXL is needed before any conclusions on the effect of the supercluster environment on AGN can be reached. © ESO, 2016. [less ▲]

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See detailThe XXL Survey XIV. AAOmega Redshifts for the Southern XXL Field
Lidman, C.; Ardila, F.; Owers, M. et al

in Publications of the Astronomical Society of Australia (2016), 33

We present a catalogue containing the redshifts of 3 660 X-ray selected targets in the XXL southern field. The redshifts were obtained with the AAOmega spectrograph and 2dF fibre positioner on the Anglo ... [more ▼]

We present a catalogue containing the redshifts of 3 660 X-ray selected targets in the XXL southern field. The redshifts were obtained with the AAOmega spectrograph and 2dF fibre positioner on the Anglo-Australian Telescope. The catalogue contains 1 515 broad line AGN, 528 stars, and redshifts for 41 out of the 49 brightest X-ray selected clusters in the XXL southern field. Copyright © Astronomical Society of Australia 2016. [less ▲]

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See detailPhysical properties of the planetary systems WASP-45 and WASP-46 from simultaneous multiband photometry
Ciceri, S.; Mancini, L.; Southworth, J. et al

in Monthly Notices of the Royal Astronomical Society (2016), 456(1), 990-1002

Accurate measurements of the physical characteristics of a large number of exoplanets are useful to strongly constrain theoretical models of planet formation and evolution, which lead to the large variety ... [more ▼]

Accurate measurements of the physical characteristics of a large number of exoplanets are useful to strongly constrain theoretical models of planet formation and evolution, which lead to the large variety of exoplanets and planetary-system configurations that have been observed. We present a study of the planetary systemsWASP-45 andWASP-46, both composed of a mainsequence star and a close-in hot Jupiter, based on 29 new high-quality light curves of transits events. In particular, one transit of WASP-45 b and four of WASP-46 b were simultaneously observed in four optical filters, while one transit of WASP-46 b was observed with the NTT obtaining a precision of 0.30 mmag with a cadence of roughly 3 min. We also obtained five new spectra of WASP-45 with the FEROS spectrograph. We improved by a factor of 4 the measurement of the radius of the planet WASP-45 b, and found that WASP-46 b is slightly less massive and smaller than previously reported. Both planets now have a more accurate measurement of the density (0.959 ± 0.077 ρJup instead of 0.64 ± 0.30 ρJup for WASP-45 b, and 1.103 ± 0.052 ρJup instead of 0.94 ± 0.11 ρJup for WASP-46 b). We tentatively detected radius variations with wavelength for both planets, in particular in the case of WASP-45 b we found a slightly larger absorption in the redder bands than in the bluer ones. No hints for the presence of an additional planetary companion in the two systems were found either from the photometric or radial velocity measurements. © 2015 The Authors. [less ▲]

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