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See detailLixiviation bactérienne de concentrés métalliques issus des résidus de craquage catalytique
Bastin, David ULiege; Lewis, Grégory

Report (2009)

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See detailLL-diaminopimelic acid containing peptidoglycans in walls of Streptomyces sp. and of Clostridium perfringens (type A).
Leyh-Bouille, Mélina; Bonaly, Roger; Ghuysen, Jean-Marie ULiege et al

in Biochemistry (1970), 9(15), 2944-2952

In a major part of the wall peptidoglycans of Streptomyces sp. and of Clostridium perfringens, L-alanyl-D-isoglutaminyl-(L1)-LL-diaminopimelyl-(L1)-D-alanine peptides are cross-linked via D-alanylglycyl ... [more ▼]

In a major part of the wall peptidoglycans of Streptomyces sp. and of Clostridium perfringens, L-alanyl-D-isoglutaminyl-(L1)-LL-diaminopimelyl-(L1)-D-alanine peptides are cross-linked via D-alanylglycyl-(L2)-LL-diaminopimelic acid linkages (peptidoglycan of the chemotype II group). The Myxobacter AL-I endopeptidase hydrolyzes both D-alanyl-glycine and glycyl-LL-diaminopimelic acid linkages in the walls of C. perfringens, liberating free glycine. In contrast, the Myxobacter AL-I endopeptidase hydrolyzes only D-alanyl-glycine linkages in walls of Streptomyces sp. and the liberation of the glycine residues requires subsequent treatment with an aminopeptidase. No explanation for this observation can be proposed at this time. A minor component of the AL-I endopeptidase hydrolysate of the Streptomyces and C. perfringens walls is a resistant peptide dimer. Analyses indicate that the cross-link in this dimer may be mediated through LL-diamino-pimelylglycyl-LL-diaminopimelic acid linkages. The C termini of the peptide moieties in the wall peptidoglycans are either D-alanine or LL-diarninopimelic acid but never D-alanyl-D-alanine, thus indicating the presence in these microorganisms of carboxypeptidases similar to those of Escherichia coli. [less ▲]

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See detailLlandovery biostratigraphy of the Paraná Basin, East Paraguay
Mendlowicz Mauller, P.; Pereira, E.; Grahn, Y. et al

Conference (2004)

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See detailLlandovery miospore biostratigraphy and stratigraphic evolution of the Parana Basin, Paraguay - Palaeogeographic implications
Steemans, Philippe ULiege; Pereira, E.

in Bulletin de la Société Géologique de France (2002), 173(5), 407-414

The Parana Basin covers 1,600,000 km(2) including parts of southern Brazil, Paraguay, Uruguay and Argentina. It contains rocks ranging from the Ordovician to Tertiary in age. The present study is focused ... [more ▼]

The Parana Basin covers 1,600,000 km(2) including parts of southern Brazil, Paraguay, Uruguay and Argentina. It contains rocks ranging from the Ordovician to Tertiary in age. The present study is focused on the Itacurubi Group, of Llandovery age, from Paraguay. The sedimentology and palynology have been studied in three boreholes from the central part of Paraguay. The Itacurubi Group consists of the Euzebio Ayala, Vargas Pena and Cariy Formations. It corresponds to a complete transgressive - regressive cycle with maximum flooding in the Vargas Pena Formation. The sediments of the group were deposited in a glacio-marine regime and are included in the second order sequence. The palynofacies are dominated by acritarchs and chitinozoans, with miospores rare. Among the latter, cryptospores are most abundant and trilete spores very rare. The miospore assemblages are typical of the Llandovery. The presence of Laevolancis divellomedia and the successive first occurrence of the trilete spore genus Ambitisporites, followed by Archaeozonotriletes, allow the recognition of three biozones : divellomedia I, divellomedia II and chulus-nanus. Correlations between the three boreholes based on miospore biostratigraphy and sequence stratigraphy techniques are similar. The miospore assemblages have important palaeogeographic implications: (1) Ordovician / Silurian miospore assemblages, identified in South America are similar to those described in palaeogeographically distinct regions such as China, UK, Belgium, USA etc. This suggests that the phytogeographical differentiation proposed by Gray et al. [1992], with a Malvinokaffric Realm characterised by smooth tetrads and an extra-Malvinokaffric Realm characterised by ornamented tetrads, has to be reconsidered. Clearly, the same miospores are recovered from both regions, no matter if they are close to the palaeo-equator or the palaeo-pole, as is the case in Paraguay. These findings suggest that the same vegetation could survive under various climates. (2) In theory, large oceans could be impassable geographic barriers for land plant miospores larger than 25 mum in diameter. As similar miospore assemblages occur, around the Ordovician - Silurian boundary, on the Gondwana, Avalonia and Laurentia plates, it seems likely that these palaeo-continental plates were in close proximity permitting the expansion of the vegetation through these continents. Therefore, palaeogeographic reconstructions with narrow oceans between the continents better explain early miospore biogeographies in early Silurian times. (3) Maps produced by Dalziel et al. [1994] better explain the diachronism of trilete spore first appearances Hirnantian in Turkey, Rhuddanian in Saudi Arabia, early Aeronian in Libya, late Aeronian in Paraguay, latest Aeronian in UK, and possibly Telychian in USA. (4) The Baltica plate could possibly have been isolated by a geographic barrier during the Ashgill and the Llandovery, as only simple naked tetrads are known from that plate. The first appearance of the trilete spores in Gotland during the early Wenlock could correspond to the end of this geographic isolation. This apparent isolation of the Baltica plate could be due to a lack of data. [less ▲]

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See detailLloyd relaxation using analytical Voronoi diagram in the L_infinite norm and its application to quad optimization
Mouton, Thibaud ULiege; Béchet, Eric ULiege

in Jiao, Xiangmin (Ed.) Proceedings of the 21st International Meshing Roundtable (2012)

An incremental Delaunay triangulation algorithm to generate Voronoi diagrams within the L∞ norm is presented. The main qualities are the preserva- tion of the simplicity of the classical L2 version and ... [more ▼]

An incremental Delaunay triangulation algorithm to generate Voronoi diagrams within the L∞ norm is presented. The main qualities are the preserva- tion of the simplicity of the classical L2 version and its its intrinsic robustness It is then coupled to the well known Lloyd algorithm for computing Centroidal Voronoi Tesselations of point sets. This algorithm is then used to generate well shaped quadri- lateral meshes. [less ▲]

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See detailThe LMC transition star R 84 and the core of the LH 39 OB association.
Heydari-Malayeri, M.; Courbin, F.; Rauw, Grégor ULiege et al

in Astronomy and Astrophysics (1997), 326

On the basis of sub-arcsecond imaging obtained at the ESO NTT with SUSI and the ESO ADONIS adaptive optics system at the 3.6m telescope, we resolve and study the core components of the LMC OB association ... [more ▼]

On the basis of sub-arcsecond imaging obtained at the ESO NTT with SUSI and the ESO ADONIS adaptive optics system at the 3.6m telescope, we resolve and study the core components of the LMC OB association LH 39. The central star of the association, the rare transition object R 84, is also investigated using CASPEC echelle spectroscopy at the ESO 3.6m telescope. A new, powerful image restoration code that conserves the fluxes allows us to obtain the magnitudes and colors of the components. We bring out some 30 stars in a ~16"x16" area centered on R 84. At a resolution of 0.19"(FWHM), the closest components to R 84 are shown to be stars #21 and #7 lying at 1.1"NW and 1.7"NW respectively of the transition star. The former is possibly a blue star of V=16.7mag and the latter with its V=17.5mag is the reddest star of the field, after R 84. Star #7 turns out to be too faint to correspond to the red M2 supergiant previously reported to contaminate the spectrum of R 84. If the late-type spectrum is due to a line-of-sight supergiant with a luminosity comparable to R 84, it should lie closer than 0.12" to R 84. The transition star shows spectral variability between 1982 and 1991. We also note some slight radial velocity variations of the Of emission lines over timescales of several years. Furthermore, we derive the spectral types of two of the brightest stars of the cluster, using long slit spectra obtained at the NTT telescope equipped with EMMI, and discuss the apparent absence of O type stars in this association. [less ▲]

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See detailLNCaP prostate cancer imaging with biologically functionalized gold nanoparticles in 2D and 3D cell culture
Schol, Daureen ULiege; Fleron, Maximilien ULiege; Greisch, Jean - François et al

in Anticancer Research (2008), 28

One of the main objectives of this project is to realize and validate a versatile lab system composed of functionalized nanoparticles for diagnosis of different superficial and accessible cancers, e.g ... [more ▼]

One of the main objectives of this project is to realize and validate a versatile lab system composed of functionalized nanoparticles for diagnosis of different superficial and accessible cancers, e.g. prostate cancer. Gold nanorods have been synthesized and functionalized with antibodies targeting specific antigens on cancer cell lines. [less ▲]

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See detailLNG carrier – new innovative product
Constantinescu, A.; Rigo, Philippe ULiege; Guillaume Combecave, J.-L.

in IMPROVE Workshop (EU Project FP6 n°031382), DUBROVNIK 17-18 Sept. 2009, Croatia, Editor V. Zanic – Univ. of Zagreb (2009, September)

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See detailLNG carrier- Structural design aspects
Amrane, Amirouche ULiege; Constantinescu, Adrien; Bair, Frédéric ULiege et al

in IMPROVE Workshop (EU Project FP6 n°031382), DUBROVNIK 17-18 Sept. 2009, Croatia, Editor V. Zanic – Univ. of Zagreb, pp90-95 (Vol I) (2009, September)

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See detailThe LNQ25 and ELN PVT Metrics Exhibit a Good Sensitivity to Sleep Deprivation and are Independent from the Subject
Latour, Philippe ULiege; Van Droogenbroeck, Marc ULiege

Poster (2017, October 09)

Introduction Performance of people undergoing critical tasks (like driving) may be impaired completely by the lowering of their vigilance level, due to sleep deprivation for instance. This reduction of ... [more ▼]

Introduction Performance of people undergoing critical tasks (like driving) may be impaired completely by the lowering of their vigilance level, due to sleep deprivation for instance. This reduction of performance may be measured by metrics computed from the reaction times (RT) recorded during a 10min Psychomotor Vigilance Test (PVT). Here, we analyze and compare the sensitivity to sleep deprivation and the subject dependent variability of the PVT metrics performance, with a special emphasis on the time interval sizes. Materials and Methods Individuals (22 volunteers; 11 males, 11 females, mean 22.2y., range 19-34 years) follow an uninterrupted 28h sleep deprivation standard PVT protocol during which they achieved two groups of three PVT sessions (in different conditions). The first PVT of each group is in Non-SDP condition (9h30 and 10h30 Day 1) and the second and third PVT of each group are in SDP condition (2h30, 3h30, 10h30 and 11h30 day 2). The subjects fill a sleep journal during the week before the experiment. We checked that they had a normal sleep-wake cycle with no sleep deprivation, jet-lag or shift work and no medication. During the PVT of the first group, the subjects were wearing the glasses of the Phasya’s Drowsimeter. We compute the usual PVT metrics; meanRT, meanRS (Reaction Speed) and LN500 (500ms lapses number). We also compute LNQ25 (adaptive lapses number computed with a subject dependent threshold) and ELN (Expected Lapse Number, computed from a subject-dependent estimation of the lapse probability). Results We use the “Effect Size” (ES, ratio of the mean by the standard deviation of the difference of metrics in the SDP and Non-SDP conditions) to assess the sensitivity to sleep deprivation. For the 10min (resp. 1min, 3min) interval, the ES of LNQ25 and ELN are respectively 1.38 (resp. 0.95, 1.22) and 1.35 (resp. 0.85, 1.14), the ES of meanRS, meanRT and LN500 are 1.23 (resp. 0.91, 1.09), 0.81 (resp. 0.54, 0.68) and 0.85 (resp. 0.63, 0.77). We classify the intervals on which metrics are computed as SDP or non-SDP. We use a fixed threshold for the metrics, independent of the subject. In the ROC curves, the TPR (for a FPR of 10%) assesses the quality of the classification, and then also the subject independence. For the 10min (resp. 1min, 3min) interval, the TPR of LNQ25 and ELN are respectively 0.86 (resp. 0.56, 0.75) and 0.83 (resp. 0.58, 0.75), the TPR of meanRS, meanRT and LN500 are 0.42 (resp. 0.38, 0.41), 0.40 (resp. 0.39, 0.40) and 0.42 (resp. 0.24, 0.30). Conclusions We demonstrate that LNQ25 and ELN enable a quite good classification of the SDP condition for time intervals greater than or equal to 3min, independently of the subject. On the other hand, these metrics provide also a good sensitivity to sleep deprivation. They outperform the usual metrics for both criteria. For time intervals below 3min, the performances degrade first progressively and then much more quickly below 1min. [less ▲]

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See detailLo specchio secondario adattivo dell’LBT: calibrazione del prototipo P45
Ricci, Davide ULiege

Master's dissertation (2006)

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See detailLoad modulation strategies of residential heat pumps for demand-response programs with different thermal storage options
Georges, Emeline ULiege; Lemort, Vincent ULiege

in Proceedings of the 4th International High Performance Buildings Conference at Purdue (2016, July)

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See detailLoad Shedding Controllers against Voltage Instability: a comparison of designs
Moors, Cedric; Lefebvre, Daniel; Van Cutsem, Thierry ULiege

in Proc. IEEE Porto Power Tech Conference (2001, September)

This paper discusses and compares three types of undervoltage load shedding closed-loop controllers in terms of performances and design computational effort. We first describe the various controllers and ... [more ▼]

This paper discusses and compares three types of undervoltage load shedding closed-loop controllers in terms of performances and design computational effort. We first describe the various controllers and identify the parameters to be optimized. Next, we present an optimization methodology applicable to all three types of controllers. This approach allows to find the controller parameters which optimize an overall performance objectiw. Results are presented on the Hydro-Qukbec system, in which load shedding is presently planned. [less ▲]

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See detailA load shedding scheme against both short- and long-term voltage instabilities in the presence of induction motors
Otomega, Bogdan; Van Cutsem, Thierry ULiege

in Proceedings of the IEEE Trondheim Power Tech 2011 conference (2011, June)

In the presence of induction motors in loads, long-term voltage instability may result in sharp voltage decreases, once the generators supporting transmission voltages have their field currents limited ... [more ▼]

In the presence of induction motors in loads, long-term voltage instability may result in sharp voltage decreases, once the generators supporting transmission voltages have their field currents limited. Furthermore, after a fault, induction motors may fail re-accelerating and their stalling leads to short-term voltage instability. This paper investigates the ability of the load shedding scheme, previously proposed by the authors, to deal with both short and long-term voltage instabilities. The scheme is distributed with minimal amount of information exchange. It is also shown that the selectivity of this protection scheme can be increased by prioritizing in time the various controllers. Detailed time simulations of a test system are reported. [less ▲]

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See detailLoad-Introdcution resistance of column webs in strong axis beam-to-column joints
Maquoi, René ULiege; Jaspart, Jean-Pierre ULiege

Learning material (1992)

Present paper is aimed at presenting the results of the study performed at F1 the University of Liege on the deformability and the resistance of column H5 web panels in strong axis beam-to-column joints ... [more ▼]

Present paper is aimed at presenting the results of the study performed at F1 the University of Liege on the deformability and the resistance of column H5 web panels in strong axis beam-to-column joints, when subjected to ‘:5 transverse loads carried over by the beam(s). "S Formulae for the assessment of the ultimate resistance and stability E (buckling and crippling) of the column webs are proposed; they are based on me the conclusions of a parametrical study which is briefly described. b‘ Present paper is restricted to the beam-to-column joints with ll or I E‘ hobrolled sections. [less ▲]

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See detailLoad-introduction deformability of column webs in strong axis beam-to-column joints and structural stability of frames.
Jaspart, Jean-Pierre ULiege; Atamaz Sibai, W.

in Proceedings of the Fourth international colloquium on structural stability asian session (ICSSAS'89) (1989)

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See detailLoadbearing capacity criteria in fire resistance testing
Dumont, Fabien ULiege; Wellens, Eric ULiege; Gernay, Thomas ULiege et al

in Materials and Structures (2016), 49(11), 4565-4581

The European system for fire testing and classification of loadbearing building elements lacks consistency because the two standards that have to be applied prescribe different criteria for assessing the ... [more ▼]

The European system for fire testing and classification of loadbearing building elements lacks consistency because the two standards that have to be applied prescribe different criteria for assessing the loadbearing performance. This article analyzes the implications of the present conflict between the standard for testing and the standard for classification. The prescribed criteria for loadbearing performance are related to the exceedance of deflection and rate of deflection thresholds. A database of 46 fire resistance tests performed at the University of Liege is collected that contains the time at which these thresholds are reached in fire tests with different typologies of elements (walls, floors, columns and beams). Then, the loadbearing performance (and hence the fire resistance rating) can be derived according to the two standards. The evolutions of deflection and rate of deflection during the tests are also analyzed to gain a better understanding of the adequacy of the standards. The selection of one or the other standard affects the time at which “failure” is deemed to occur in fire tests. Statistically speaking, the difference in terms of failure time that results from using one or the other standard has a 25% probability to exceed 10%. In certain cases, this results in a difference in fire resistance rating; this was observed for 3 of the analyzed tests. The apparent contradiction in two codes in application has potential practical implications and therefore needs to be solved. The article suggests some guidelines for defining homogenized and consistent criteria. [less ▲]

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See detailLoadbearing capacity criteria in fire resistance testing
Dumont, Fabien ULiege; Wellens, Eric ULiege; Franssen, Jean-Marc ULiege

Report (2015)

Experimental testing may be used to demonstrate the fire resistance of building construction elements. In order to allow comparing the results of tests made in different laboratories on various types of ... [more ▼]

Experimental testing may be used to demonstrate the fire resistance of building construction elements. In order to allow comparing the results of tests made in different laboratories on various types of elements, the tests have to be performed under well-defined standardised conditions. Such standards define the heating and loading conditions, but also the performance criteria that have to be applied to measure the fire resistance duration. In Europe, the procedure that leads to the classification of building construction elements with regards to fire resistance involves a two level process. In the first stage, one or several tests are performed by a laboratory that must have accreditation according to ISO 17025, and one test report is issued for each test. Thereafter, a competent body will compile the necessary test reports and issue a classification report, the results of which can be used by the different stakeholders of the construction process, e.g. by authorities having jurisdiction. For the loadbearing performance, it appears that different logical combinations of the criteria are considered in the test standard and in the classification standard, leading to a inextricable situation. This situation has to be fixed in order to lead to a complete credible and applicable system. In order to provide scientific evidence about the consequences of adopting one or the other of both loadbearing definitions, the results of 46 tests performed in the fire resistance lab of the University of Liege in the recent years are analysed in this paper. [less ▲]

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