References of "2011"
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See detailThe development of female sexual behavior requires prepubertal estradiol.
Brock, Olivier; Baum, Michael J; Bakker, Julie ULg

in Journal of Neuroscience (2011), 31(15), 5574-8

The classic view of brain and behavioral sexual differentiation holds that the neural mechanisms controlling sexual behavior in female rodents develop in the absence of ovarian sex hormone actions ... [more ▼]

The classic view of brain and behavioral sexual differentiation holds that the neural mechanisms controlling sexual behavior in female rodents develop in the absence of ovarian sex hormone actions. However, in a previous study, female aromatase knock-out (ArKO) mice, which cannot convert testosterone to estradiol, showed deficient male-oriented partner preference and lordosis behaviors in response to adult ovarian hormones, raising the possibility that estradiol may contribute to the development of these female sexual behaviors. In the present experiments, administering estradiol prepubertally [between postnatal day 15 (P15) and P25] significantly enhanced the ability of ArKO female mice to display lordosis behavior in response to ovarian hormones administered later in adulthood, whereas treatment with estradiol over an earlier postnatal period (P5-P15) had no such effect. Treatment of ArKO females with estradiol between P15 and P25 also rescued their later preference to approach distal cues from an intact male over an estrous female. ArKO females also displayed significantly less female-directed (male-typical) mounting behavior than wild-type control females when treated with testosterone in adulthood. Prepubertal estradiol treatment failed to reverse this deficit in ArKO females, whereas earlier postnatal estradiol augmented later mounting in both genotypes. Our results provide new evidence for an organizing role of prepubertal estradiol in the development of neural mechanisms that control female-typical sexual behavior. [less ▲]

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See detailTowards Laser Cooling of Iron Atoms
Bastin, Thierry ULg

Conference (2011)

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See detailLong-expected! - First record of demosponge-type spicules in a Devonian stromatoporoid (Frasnian, Belgium).
Da Silva, Anne-Christine ULg; Kershaw, Stephen; Boulvain, Frédéric ULg et al

in Kölner Forum für Geologie und Paläontologie (2011), 19

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See detailScreening for colorectal cancer in asymptomatic average risk patients: role of imaging.
Hock, D.; Ouhadi, R.; Materne, R. et al

in Acta Gastro-Enterologica Belgica (2011), 74(1), 70-6

Early detection of colorectal cancer or advanced adenomas is a public health priority in many industrialized countries. There are various methods of screening average risk individuals for colorectal ... [more ▼]

Early detection of colorectal cancer or advanced adenomas is a public health priority in many industrialized countries. There are various methods of screening average risk individuals for colorectal cancer, and their effectiveness may depend on subjective parameters like local expertise and patient's preferences. This paper reviews these tests with special emphasis regarding imaging techniques that aim to provide less-invasive alternatives to optical colonoscopy (OC) which is the standard of reference. Both Double-Contrast Barium Enema (DCBE) and Virtual Colonoscopy (VC) have >90% sensitivity compared to OC in the detection of clinically relevant colonic lesions. Nevertheless, VC may have an edge over DCBE for technical and reproductivity reasons, as well as greater learning opportunities. Imaging techniques criticisms regarding diminutive and flat lesions, cost, radiation exposure and effects on gastroenterological practice are addressed. [less ▲]

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See detailNonlinear Normal Modes: A Finite Element Approach
Renson, Ludovic ULg; Kerschen, Gaëtan ULg

Conference (2011)

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See detailModal Analysis of Nonlinear Vibrating Systems: Recent Progress and Challenges, KEYNOTE LECTURE
Kerschen, Gaëtan ULg

in Proceeedings of the Eighth European Conference on Structural Dynamics (2011)

Theoretical and experimental modal analysis, i.e., the computation of vibration modes from a mathematical model and from experimental data, respectively, is quite sophisticated and advanced in linear ... [more ▼]

Theoretical and experimental modal analysis, i.e., the computation of vibration modes from a mathematical model and from experimental data, respectively, is quite sophisticated and advanced in linear structural dynamics. However, nonlinearity is a frequent occurrence in real-world engineering structures, and the existing linear methodologies can no longer be used in this context. Therefore, the development of a nonlinear analog of modal analysis would be a timely contribution. Because nonlinear normal modes (NNMs) provide solid mathematical foundations for a rigorous analysis of nonlinear dynamical behaviors, a framework which includes both their computation from finite element models and their identification from experimental data is proposed in this paper. In view of the still limited use of NNMs in structural dynamics, special attention is devoted to develop tools that have the potential to deal with large-scale structures. [less ▲]

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See detailExpression, purification of novel alkaline Staphylococcus xylosus lipase acting at high temperature
Bouaziz, Ahlem ULg; Habib, Horchani; Ben Salem, Nadia et al

in Biochemical Engineering Journal (2011), 54

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See detailDeterminants of high, median and low rates of caesarean deliveries in Belgium
Absil, Gaëtan ULg; Van Parys, A. S.; Bednarek, Stéphanie et al

Report (2011)

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See detailNew method to combine molecular and pedigree relationships
Bömcke, Elisabeth ULg; Soyeurt, Hélène ULg; Szydlowski, Maciej et al

in Journal of Animal Science (2011), 89

Relationship coefficients are traditionally based on pedigree data. Today, with the development of molecular techniques, they are often completely replaced by coefficients calculated from molecular data ... [more ▼]

Relationship coefficients are traditionally based on pedigree data. Today, with the development of molecular techniques, they are often completely replaced by coefficients calculated from molecular data. Examples are relationships from microsatellites for biodiversity studies but also genomic relationships from SNP as currently used in genomic prediction of breeding values. There are, however, many situations in which optimal combination of both sources would be the best solutions. Obviously, this is the case for incompletely genotyped populations, but also when pedigree information is sparse. Also, markers, even dense ones, do not reflect the whole genome and therefore give only an incomplete picture of relationships. The main objective of this study was therefore to develop a method to calculate a relationship matrix by the combination of molecular and pedigree data. It will be useful for all situations where pedigree and molecular data are available. In this study, based on simulations of pedigree and marker data, we used partial least squares regression and linear regression to combine total allelic relationship coefficients calculated for each marker with additive relationship coefficients calculated from incomplete pedigree. The results showed that the greatest advantage of this method, compared with the one that replaces a part of the pedigree-based relationship matrix by a genomic relationship matrix, is that adding the partial pedigree data allows for the correction of the molecular coefficient for the ungenotyped part of the genome. [less ▲]

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See detailNew Methodology to detect toxin-GPCR binding by MALDI-TOF Mass Spectrometry
Echterbille, Julien ULg; De Pauw, Edwin ULg; Gilles, Nicolas et al

Poster (2011)

Introduction More than 50 thousands of venomous species are currently indexed in the world. Each of their venoms is composed of 200 to 1000 different toxins which potentially exhibit a high selectivity ... [more ▼]

Introduction More than 50 thousands of venomous species are currently indexed in the world. Each of their venoms is composed of 200 to 1000 different toxins which potentially exhibit a high selectivity for membrane receptors such as ionic channels or G-protein coupled receptors (GPCRs). GPCRs constitute the larger family of receptors since around 800 different kinds of them are knows. GPCRs are the target of around 30% of the current pharmacopeia drugs. Notable examples include Novartis’s Zelnorm, Eli Lilly’s Zyprexa and Schering-Plough’s Clarinex used to treat constipation, schizophrenia and allergies, respectively. Finding new GPCRs ligands appears of prime interest to design new pharmacological tools and potentially discover the drugs of our future. Interestingly, several toxins from venoms have already been described to bind to this particular family of receptor, opening the way to the discovery of new peptide drugs from animal venoms1-2. This work presents a pioneering MALDI-TOF/TOF based strategy to fish new GPCRs ligands from complex mixtures such as venom fractions. Methods The proof of concept of this methodology was built by studying the binding of [Arg8]-vasopressin (AVP) on type 2-vasopressin receptor (V2). Experimentally, fragments of cellular membranes over-expressing V2 receptors were incubated with cone snail’s venom fraction (~30 peptide toxins) doped by a small amount of AVP. After 2 hours incubation, free and bound fractions were carefully purified with a combination of centrifugation and micro column purifications. Samples were finally analyzed with a Bruker Ultraflex II MALDI-TOF/TOF mass spectrometer and the resulting spectra were interpreted with FlexAnalysis (v3.0), BioTools (v3.2) and SequenceEditor (v3.2) bioinformatics’ softwares from Bruker Daltonics. Preliminary data After the incubation of cellular membranes overexpressing V2 GPCR with a complex mixture of peptides doped by AVP, we clearly detect that the only V2 ligand present in the fraction was the AVP. Our result demonstrates the possibility to identify a ligand of GPCRs from a complex peptide mixture, such as venom fractions. Contrary to radiobinding, this approach allows detecting the direct binding of the toxin and does not imply to know a ligand of the studied GPCR before starting the experiments. This opens the way to the deorphanization of receptors (180 orphans GPCRs over 800). Moreover, since the new ligand is detected by mass spectrometry, it is directly identified from the mixture, without additional purification. Its structural characterization can be directly performed by de novo sequencing experiments. The drawback of our approach is the very long (but crucial!) sample preparation as each sample requires 2 purification steps (for both free and bound fraction). The next step of our work will be the automation of the procedure to allow a high-throughput screening of venom fractions on different GPCRs and the discovery of new ligands. Novel aspect GPCR’s ligands discovery by MALDI-TOF/TOF based techniques: a new pharmacological tool. 1 Quinton, L. et al. Isolation and pharmacological characterization of AdTx1, a natural peptide displaying specific insurmountable antagonism of the a1A-adrenoceptor. British Journal of Pharmacology 159, 316-325 (2010). 2 Rouget, C. et al. Identification of a novel snake peptide toxin displaying high affinity and antagonist behaviour for the α2-adrenoceptors. British Journal of Pharmacology 161, 1361-1374, doi:10.1111/j.1476-5381.2010.00966.x (2010). [less ▲]

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See detailAnalytical validation of the Liaison Calcitonin_II-Gen (DiaSorin)
Cavalier, Etienne ULg; Carlisi, Ignazia ULg; Bekaert, Anne-Catherine ULg et al

in Clinical Chemistry & Laboratory Medicine (2011), 49(2), 271-275

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See detail1D numerical modeling of the flow over a Piano Key Weir
Erpicum, Sébastien ULg; Machiels, Olivier ULg; Archambeau, Pierre ULg et al

in Erpicum, Sébastien; Laugier, Frédéric; Boillat, Jean Louis (Eds.) et al Labyrinth and Piano Key Weirs - PKW 2011 (2011)

Because of the PK-Weir geometric specificities, its hydraulic capacity remains difficult to predict without using experimental techniques. A 1D numerical model of the flow over a PK-Weir has been ... [more ▼]

Because of the PK-Weir geometric specificities, its hydraulic capacity remains difficult to predict without using experimental techniques. A 1D numerical model of the flow over a PK-Weir has been developed at the Research unit HACH at the University of Liege. It is based on a 1D modeling of the inlet and the outlet separately, with a single upstream reservoir and interactions between both flows by exchange of mass and momentum along the lateral crest. The comparison of the numerical results with various experimental data showed the ability of the numerical model to predict with reasonable accuracy the release capacity of a PK-Weir, whatever its geometry. The tests of the solver enable to highlight the significant influence of the inlet and outlet width on the weir release capacity. They also suggest that improvements of the numerical model may lie in the evaluation of the discharge coefficient of the lateral crest. [less ▲]

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See detailField trip 3: Uppermost Devonian and Lower Carboniferous of Southern Belgium
Poty, Edouard ULg; Aretz, Markus; Denayer, Julien ULg

in Kölner Forum für Geologie und Paläontologie (2011), 20

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See detailL'imperatrice. Le Molte Vite di Indira Gandhi
Maiorano, Diego ULg

in Storia della Storiografia (2011), 58

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See detailOptimal design of multi-subject blocked fMRI experiments.
Maus, Bärbel ULg; van Breukelen, Gerard J P; Goebel, Rainer et al

in NeuroImage (2011), 56(3), 1338-1352

The design of a multi-subject fMRI experiment needs specification of the number of subjects and scanning time per subject. For example, for a blocked design with conditions A or B, fixed block length and ... [more ▼]

The design of a multi-subject fMRI experiment needs specification of the number of subjects and scanning time per subject. For example, for a blocked design with conditions A or B, fixed block length and block order ABN, where N denotes a null block, the optimal number of cycles of ABN and the optimal number of subjects have to be determined. This paper presents a method to determine the optimal number of subjects and optimal number of cycles for a blocked design based on the A-optimality criterion and a linear cost function by which the number of cycles and the number of subjects are restricted. Estimation of individual stimulus effects and estimation of contrasts between stimulus effects are both considered. The mixed-effects model is applied and analytical results for the A-optimal number of subjects and A-optimal number of cycles are obtained under the assumption of uncorrelated errors. For correlated errors with a first-order autoregressive (AR1) error structure, numerical results are presented. Our results show how the optimal number of cycles and subjects depend on the within- to between-subject variance ratio. Our method is a new approach to determine the optimal scanning time and optimal number of subjects for a multi-subject fMRI experiment. In contrast to previous results based on power analyses, the optimal number of cycles and subjects can be described analytically and costs are considered. [less ▲]

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See detailNegations at Medinet Habu
Gillen, Todd Jonathan ULg

Conference (2011)

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See detailBrain natriuretic peptide in asymptomatic degenerative mitral regurgitation: determinants and impact on outcome.
Van de Heyning, C; Magne, Julien ULg; Mahjoub, H et al

Conference (2011)

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See detailWeighted Banzhaf power and interaction indexes through weighted approximations of games
Marichal, Jean-Luc; Mathonet, Pierre ULg

in European Journal of Operational Research (2011), 211

The Banzhaf power index was introduced in cooperative game theory to measure the real power of players in a game. The Banzhaf interaction index was then proposed to measure the interaction degree inside ... [more ▼]

The Banzhaf power index was introduced in cooperative game theory to measure the real power of players in a game. The Banzhaf interaction index was then proposed to measure the interaction degree inside coalitions of players. It was shown that the power and interaction indexes can be obtained as solutions of a standard least squares approximation problem for pseudo-Boolean functions. Considering certain weighted versions of this approximation problem, we define a class of weighted interaction indexes that generalize the Banzhaf interaction index. We show that these indexes define a subclass of the family of probabilistic interaction indexes and study their most important properties. Finally, we give an interpretation of the Banzhaf and Shapley interaction indexes as centers of mass of this subclass of interaction indexes. [less ▲]

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