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See detailCompletion of biological networks: the output kernel trees approach
Geurts, Pierre ULg; Touleimat, Nizar; Dutreix, Marie et al

in Proceedings of the the Workshop on Probabilistic Modeling and Machine Learning in Structural and Systems Biology (2006)

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See detailA complex anterior mediastinal mass: demonstration of pericardial haemangioma by dynamic MRI (2003:10b).
NCHIMI LONGANG, Alain ULg; Ghaye, B.; Szapiro, D. et al

in European Radiology (2004), 14(1), 160-3

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See detailA complex composed of at least two HeLa nuclear proteins protects preferentially one DNA strand of the simple (gt)n(ga)m containing region of intron 2 in HLA-DRB genes.
Maueler, Winfried; Frank, G.; Muller, Marc ULg et al

in Journal of Cellular Biochemistry (1994), 56(1), 74-85

Electrophoretic mobility shift assays reveal that HeLa nuclear proteins bind fast and with measurable affinity to target DNAs containing mixed simple repetitive (gt)n(ga)m stretches. Preincubation of the ... [more ▼]

Electrophoretic mobility shift assays reveal that HeLa nuclear proteins bind fast and with measurable affinity to target DNAs containing mixed simple repetitive (gt)n(ga)m stretches. Preincubation of the proteins at elevated temperature prevents the formation of the major DNA/protein complex in favour of several distinct assemblies. A similar pattern of retarded bands was observed employing higher salt concentrations in the binding reaction. Thus conformational changes of different proteins appear to influence the complex rather than alternating DNA structures. Separation of the total nuclear extract into a water soluble and an insoluble protein fraction leads to a complete loss of target DNA binding capability of the fractions. The binding capacity is restored by combining the two fractions suggesting that at least two protein components are necessary to form a complex with the target sequence. The proteins can be differentiated into heat sensitive, water soluble and temperature stable, water insoluble, respectively. Furthermore, specifically binding polypeptides are not detectable by Southwestern analyses, probably because the essential components are separated during electrophoresis. DNase I footprint analyses yield four different protein binding regions only on the (gt)n(ga)m harbouring strand. The footprints cover larger portions of the mixed simple repeat in addition to a portion 5' of the (gt)n part. Hence at least two nuclear protein components of unknown biological function have to be present simultaneously to protect preferentially the (gt)n(ga)m-containing strand of intron 2 in HLA-DRB genes. [less ▲]

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See detailComplex dynamics and targeted energy transfer in linear oscillators coupled to multi-degree-of-freedom essentially nonlinear attachments
Tsakirtzis, Stylianos; Panagopoulos, Panagiotis; Kerschen, Gaëtan ULg et al

in Nonlinear Dynamics (2007), 48(3), 285-318

We study the dynamics of a system of coupled linear oscillators with a multi-DOF end attachment with essential (nonlinearizable) stiffness nonlinearities. We show numerically that the multi-DOF attachment ... [more ▼]

We study the dynamics of a system of coupled linear oscillators with a multi-DOF end attachment with essential (nonlinearizable) stiffness nonlinearities. We show numerically that the multi-DOF attachment can passively absorb broadband energy from the linear system in a one-way, irreversible fashion, acting in essence as nonlinear energy sink (NES). Strong passive targeted energy transfer from the linear to the nonlinear subsystem is possible over wide frequency and energy ranges. In an effort to study the dynamics of the coupled system of oscillators, we study numerically and analytically the periodic orbits of the corresponding undamped and unforced hamiltonian system with asymptotics and reduction. We prove the existence of a family of countable infinity of periodic orbits that result from combined parametric and external resonance interactions of the masses of the NES. We numerically demonstrate that the topological structure of the periodic orbits in the frequency-energy plane of the hamiltonian system greatly influences the strength of targeted energy transfer in the damped system and, to a great extent, governs the overall transient damped dynamics. This work may be regarded as a contribution towards proving the efficacy the utilizing essentially nonlinear attachments as passive broadband boundary controllers. [less ▲]

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See detailComplex dynamics of a linear oscillator with a nonlinear attachment
Lee, Young Sup; Kerschen, Gaëtan ULg; Vakakis, Alexander F. et al

in Fifth EUROMECH Nonlinear Dynamics Conference, Eindhoven, 2005 (2005, August)

We study the dynamics of a two-degree-of-freedom (DOF) nonlinear system consisting of a grounded linear oscillator coupled to a light mass by means of an essentially nonlinear (nonlinearizable) stiffness ... [more ▼]

We study the dynamics of a two-degree-of-freedom (DOF) nonlinear system consisting of a grounded linear oscillator coupled to a light mass by means of an essentially nonlinear (nonlinearizable) stiffness. We show that the structure of periodic orbits of the undamped system greatly influences the damped dynamics, as it causes complicated transitions between modes in the damped transient motion. In addition, there is the possibility of strong passive energy transfer (energy pumping) from the linear oscillator to the nonlinear attachment if certain periodic orbits of the undamped dynamics are excited by the initial conditions.. [less ▲]

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See detailComplex dynamics of a nonlinear aerospace structure: experimental identification and modal interactions
Noël, Jean-Philippe ULg; Renson, Ludovic ULg; Kerschen, Gaëtan ULg

in Journal of Sound & Vibration (2014), 333

Nonlinear system identification is a challenging task in view of the complexity and wide variety of nonlinear phenomena. The present paper addresses the identification of a real-life aerospace structure ... [more ▼]

Nonlinear system identification is a challenging task in view of the complexity and wide variety of nonlinear phenomena. The present paper addresses the identification of a real-life aerospace structure possessing a strongly nonlinear component with multiple mechanical stops. The complete identification procedure, from nonlinearity detection and characterization to parameter estimation, is carried out based upon experimental data. The combined use of various analysis techniques, such as the wavelet transform and the restoring force surface method, brings different perspectives to the dynamics. Specifically, the structure is shown to exhibit particularly interesting nonlinear behaviors, including jumps, modal interactions, force relaxation and chattering during impacts on the mechanical stops. [less ▲]

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See detailComplex genetic structures between nascent species in Southeast Asian Black rats (Rattus rattus complex)
Pagès, Marie ULg; Bazin, Eric; Galan, Maxime et al

Scientific conference (2012, January 19)

Black rats are among the major invasive vertebrates with severe ecological, economic and health impacts. Remarkably, their evolutionary history has received little attention and there is no firm agreement ... [more ▼]

Black rats are among the major invasive vertebrates with severe ecological, economic and health impacts. Remarkably, their evolutionary history has received little attention and there is no firm agreement on how many species should be recognized within the Black rat complex. Members of the species complex are native from India and Southeast Asia. Current taxonomy suggests that three taxa live in sympatry in several places of Thailand, Cambodia and Lao People's Democratic Republic where the present study was conducted: two accepted species (Rattus tanezumi, Rattus sakeratensis) and an additional mitochondrial lineage of unclear taxonomic status here referred as ‘Rattus R3’. We used an extensive sampling, morphological data and diverse genetic markers of different evolutionary rates and parental inheritance (two mitochondrial DNA genes, one nuclear gene and eight microsatellite loci) to assess the reproductive isolation between these three taxa. Two close Asian relatives, Rattus argentiventer and Rattus exulans, were included in the genetic analyses for comparison. Genetic analyses revealed discordant patterns between the mitochondrial and the nuclear data. The mitochondrial phylogeny identified three reciprocally monophyletic clades in the Black rat complex. Yet, the phylogeny of the nuclear exon IRBP and the clustering and assignation analyses using the eight microsatellites failed to separate tanezumi and R3. Morphometric analyses reinforced the nuclear data. The incongruence between mitochondrial data and nuclear (and morphological) data, render tanezumi/R3 paraphyletic for mitochondrial lineages with respect to sakeratensis. Different evolutionary processes such as shared ancestral polymorphism and incomplete lineage sorting or hybridization with massive mitochondrial introgression between incipient species may be invoked to account for this unusual genetic pattern in mammals. [less ▲]

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See detailComplex Hydrogeological Study of the Alluvial Transboundary Aquifer of Szamos/Somes (Romania-Hungary)
Lenart, Laszlo; Madarasz, Tamas; Miko, Lajos et al

in Water resources management in the 21th century. Subtheme 4, Relevance and sustainability of the intensive groundwater developments (2003)

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See detailThe complex injuries produced by percutaneous injection of fluids under very high pressure
RADERMECKER, Régis ULg; Thiry, A.; Beaujean, M.

in Journal of Vascular Diseases (1999, September), 11

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See detailThe complex injuries produced by percutaneous injection of fluids under very high pressure
Beaujean, M.; Thiry, A.; RADERMECKER, Régis ULg

Poster (2001, June 23)

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See detailComplex invasion pattern of the cerebral cortex bymicroglial cells during development of the mouse embryo.
Avila Macaya, Ariel Salvatore ULg

in Glia (2012)

Microglia are the immune cells of the central nervous system. They are suspected to play important roles in adult synaptogenesis and in the development of the neuronal network. Microglial cells originate ... [more ▼]

Microglia are the immune cells of the central nervous system. They are suspected to play important roles in adult synaptogenesis and in the development of the neuronal network. Microglial cells originate from progenitors in the yolk sac. Although it was suggested that they invade the cortex at early developmental stages in the embryo, their invasion pattern remains largely unknown. To address this issue we analyzed the pattern of cortical invasion by microglial cells in mouse embryos at the onset of neuronal cell migration using in vivo immunohistochemistry and ex vivo time-lapse analysis of microglial cells. Microglial cells begin to invade the cortex at 11.5 days of embryonic age (E11.5). They first accumulate at the pial surface and within the lateral ventricles, after which they spread throughout the cortical wall, avoiding the cortical plate region in later embryonic ages. The invasion of the cortical parenchyma occurs in different phases. First, there is a gradual increase of microglial cells between E10.5 and E14.5. From E14.5 to E15.5 there is a rapid phase with a massive increase in microglia, followed by a slow phase again from E15.5 until E17.5. At early stages, many peripheral microglia are actively proliferating before entering the parenchyma. Remarkably, activated microglia accumulate in the choroid plexus primordium, where they are in the proximity of dying cells. Time-lapse analysis shows that embryonic microglia are highly dynamic cells. [less ▲]

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See detailComplex magnetic ordering in Eu3InP3: A new rare earth metal zintl compound
Jiang, J.; Payne, A. C.; Olmstead, M. M. et al

in Inorganic Chemistry (2005), 44(7), 2189-2197

Eu(3)lnP(3) has been prepared as large single crystals with an indium flux reaction. The structure of the new compound is isotypic to Sr(3)lnP(3) and crystallizes in the orthorhombic space group Pnma with ... [more ▼]

Eu(3)lnP(3) has been prepared as large single crystals with an indium flux reaction. The structure of the new compound is isotypic to Sr(3)lnP(3) and crystallizes in the orthorhombic space group Pnma with unit cell dimensions of a = 12.6517(15) angstrom, b = 4.2683(5) angstrom, and c = 13.5643(14) angstrom (Z = 4, T = 140 K, R1 = 0.0404, wR2 = 0,0971 for all data). The structure consists of one-dimensional chains of corner-shared distorted [InP2P2/2](6-) tetrahedra separated by rows of Eu2+ ions. Two of the three crystallographically distinct europium sites have a short Eu(1)-Eu(2) distance of 3.5954(7) angstrom, which yields Eu-Eu dimers. The Eu-P bond distances range from 2.974(2) to 3.166(2) angstrom. The temperature dependence of the conductivity indicates that Eu(3)lnP(3) is a small band gap semiconductor. Both magnetization and Eu-151 Mossbauer spectral measurements indicate that the europium in Eu(3)lnP(3) is divalent and that at least two magnetic transitions occur. Magnetization studies reveal magnetic transitions at 14, 10.4, and similar to 5 K. These transitions are also observed in heat capacity studies of Eu(3)lnP(3). The Mossbauer spectra indicate that the two europium sites are ordered at 12 K and that all three europium sites are ordered at 8 K. [less ▲]

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See detailComplex modulation of singing behavior by testosterone in an open-ended learner, the European Starling.
Van Hout, Alain J*-M; Eens, Marcel; Balthazart, Jacques ULg et al

in Hormones & Behavior (2009), 56(5), 564-73

In many temperate zone songbird species males only produce song during the breeding season, when plasma testosterone (T) levels are high. Males of some species sing throughout the year, even when T levels ... [more ▼]

In many temperate zone songbird species males only produce song during the breeding season, when plasma testosterone (T) levels are high. Males of some species sing throughout the year, even when T levels are low, indicating a dissociation between high T levels and song rate. Given that few studies have taken advantage of these species, we compare here song traits expressed under high versus low T concentrations and we study the role of testosterone in adult song learning in the European Starling, an open-ended learner in which repertoire size dramatically increases with age. We performed a detailed comparison of song complexity and song rate between fall and spring in 6-year-old intact male European starlings. In parallel, we investigated whether potential seasonal changes were regulated by the gonadally induced increase in plasma T, by comparing seasonal changes in intact and castrated males of the same age (castrated as juveniles during their first fall) and by subsequently experimentally elevating T in half of the castrated males. While song rate and stereotypy did not differ between intacts and castrates or between fall and spring, both groups increased their average song bout length from fall to spring, but only intact males increased their repertoire size, indicating that effects of seasonal T changes differ between song traits. Intact males overall displayed a larger song repertoire and a longer bout length than the castrates, and implantation with T caused a turnover in repertoire composition in castrates. However, as the castrates had never experienced high T levels and yet displayed a markedly higher repertoire size than that of typical yearling males, this suggests that the progressive increase of song repertoire with age in male starlings is not dependent on gonadal T, although it may be T-enhanced. [less ▲]

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See detailComplex populations of minor pathogens associated with roots from barley plants infected by barley yellow mosaic virus.
Ijdenberg, P.; Kummert, J.; Lepoivre, Philippe ULg

in Parasitica (1986), 42(4),

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See detailThe Complex Problem of Ards: Pathophysiology, Management
Lamy, Maurice ULg

in Acta Anaesthesiologica Belgica (1988), 39(3 Suppl 2), 37-41

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See detailComplex protists in Mesoproterozoic rocks.
Javaux, Emmanuelle ULg; knoll, A. H.; Walter, M.

Conference (2001, April)

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See detailComplex protists in Mesoproterozoic rocks.
Javaux, Emmanuelle ULg; Knoll, A. H.; Walter, Malcolm

Conference (2001)

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See detailComplex regulation of the FRD3 gene in Arabidopsis relatives
Charlier, Jean Benoit; Polese, Catherine ULg; Nouet, Cécile ULg et al

Poster (2014, March 31)

Detailed reference viewed: 16 (4 ULg)