References of "2009"
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See detailKinematical Optimization of Closed-Loop Multibody Systems
Collard, Jean-François; Duysinx, Pierre ULg; Fisette, Paul

in Botasso, Carlo (Ed.) Multibody Dynamics - Computational Methods and Applications (2009)

Applying optimization techniques in the field of multibody systems (MBS) has become more and more attractive considering the increasing development of computer resources. One of the main issues in the ... [more ▼]

Applying optimization techniques in the field of multibody systems (MBS) has become more and more attractive considering the increasing development of computer resources. One of the main issues in the optimization of MBS concerns closed-loop systems which involve non-linear assembly constraints that must be solved before any analysis of the system. The addressed question is: how to optimize such closed-loop topologies when the objective evaluation relies on the assembly of the system? The authors have previously proposed to artificially penalize the objective function when those assembly constraints cannot be exactly fulfilled. However, the method suffers from some limitations especially due to the difficulty to get a differentiable objective function. Therefore, the key idea of this paper is to improve the penalty approach. Practically, instead of solving the assembly constraints, their norm is minimized and the residue is taken as a penalty term instead of an artificial value. Hence, the penalized objective function becomes differentiable throughout the design space, which enables the use of efficient gradient-based optimization methods such as the sequential quadratic programming (SQP) method. To illustrate the reliability and generality of the method, two applications are presented. They are related to the isotropy of parallel manipulators. The first optimization problem concerns a 3-dof Delta robot with 5 design parameters and the second one deals with a more complex 6-dof model of the Hunt platform involving 10 design variables. [less ▲]

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See detailAn 11 - Year Overview of the belgian donor and transplant statistics bsed on a consecutive yearly data follow-up and comparing two periods : 1997 to 2005 versus 2006 to 2007
Van Gelder, F.; Delbouille, Marie-Hélène ULg; Vandervennet, M. et al

in Transplantation Proceedings (2009), 41

Background. The Belgian Transplant Coordinators Section is responsible for the yearly data follow-up concerning donor and transplantation statistics in Belgium and presents herein a 10-year overview ... [more ▼]

Background. The Belgian Transplant Coordinators Section is responsible for the yearly data follow-up concerning donor and transplantation statistics in Belgium and presents herein a 10-year overview. Methods. The procurement and transplant statistics were compared between 2 periods: Period 1 (P1, 1997–2005) versus Period 2 (P2, 2006–2007). Results. The kidney and liver waiting lists (P1 vs P2) showed an overall decrease for a period of 2 consecutive years in P2; kidney ( 170 patients; 18%), and liver ( 83 patients; 34%). All other waiting lists (heart, lung, pancreas) remained stable. Mean ED further increased (P1 vs P2); 229 (P1) versus 280 (P2, 22.27%). Non–heart-beating donors were significantly ( 288%) more often procured in P2. Mean donor age was 37.9 17.8 years (P1) versus 46.5 19.9 years (P2), and mean organ yield per donor was 3.48 1.7 (P1) versus 3.38 1.8 (P2). Overall transplant activity per million inhabitants increased 21.1%. Conclusion. For 2 consecutive years, the Belgian statistics showed significantly increased donor activity with an impact on waiting list dynamics and transplantation. The mean organ yield per donor was not influenced despite an increased average age and change in reason for death. [less ▲]

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See detailDe l'idée à l'opportunité
Surlemont, Bernard ULg

in Janssen, Frank (Ed.) Entreprendre: Une introduction à l'entrepreneuriat (2009)

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See detailBone mineral density and health related quality of life: a 3-year follow-up study of osteoportic postmenopaul women
Bruyère, Olivier ULg; De Cock, Caroline; Deroisy, Rita ULg et al

in The Open Geritric Medicine Journal (2009), 2

Objective: The objective of this study was to evaluate the relationship between change in bone mineral density (BMD) and change in health related quality of life (HRQoL) over a 3-year eriod, in patients ... [more ▼]

Objective: The objective of this study was to evaluate the relationship between change in bone mineral density (BMD) and change in health related quality of life (HRQoL) over a 3-year eriod, in patients without incident of osteoporotic fracture. Materials and Methods: Prior to the present study, two randomized controlled trials had been carried out to assess the efficacy of a new anti-osteoporotic drug. From the placebo group of those two trials, we selected for the present study 1838 osteoporotic postmenopausal women aged over 50 years, and followed their progress for a period of 3 years. BMD was measured at the lumbar spine and the proximal femur by dual-energy X-ray absorptiometry. Each patient received calcium and vitamin D supplements. HRQoL was assessed using 2 questionnaires: the generic tool Short Form 36 items (SF-36; including mental and physical components) and the specific Quality of Life Questionnaire in Osteoporosis (QUALIOST). Result: At baseline, after adjustment for body mass index (BMI), age, number of vertebral fractures and number of peripheral fractures, multivariate regression analysis showed a significant association between the lumbar BMD and the mental component of the SF-36 (p<0.001). However, the relationship was not significant with the global score of the QUALIOST (p=0.098) and the physical component of the SF-36 (p=0.051). Multivariate regressions did not show a significant relationship between HRQoL and proximal femur BMD at baseline. After 3 years of follow-up, multivariate regression analysis showed no significant association between change in lumbar BMD and the main HRQoL items (global score of the QUALIOST, physical and mental components of the SF-36; p between 0.437 and 0.942). No significant relationships were found between change in femoral BMD and change in the global score of the QUALIOST (p=0.088) or change in the mental component of the SF-36 (p=0.222). However, a significant positive association (p=0.031) appeared between change in the physical component of the SF-36 and femoral BMD change. Conclusion: In osteoporotic postmenopausal women receiving calcium and vitamin D, few relationships were found between BMD and HRQoL. However, these results were not strong enough to indicate a real clinically interesting relationship between HRQoL and BMD. Other studies would need to be performed to verify these results. [less ▲]

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See detailDNA methylation and cancer diagnosis: new methods and applications.
Dehan, Pierre ULg; Kustermans, Gaëlle ULg; Guénin, Samuel ULg et al

in Expert Review of Molecular Diagnostics (2009), 9(7), 651-7

Methylation of cytosines in cytosine-guanine (CpG) dinucleotides is one of the most important epigenetic alterations in animals. The presence of methylcytosine in the promoter of specific genes has ... [more ▼]

Methylation of cytosines in cytosine-guanine (CpG) dinucleotides is one of the most important epigenetic alterations in animals. The presence of methylcytosine in the promoter of specific genes has profound consequences on local chromatin structure and on the regulation of gene expression. Changes in DNA methylation play a central role in carcinogenesis. Hypermethylation and consecutive transcriptional silencing of tumor-suppressor genes has been documented in numerous cancers. The identification of target genes silenced by this modification has a great impact on diagnosis, classification, definition of risk groups and prognosis of cancer patients. Here we outline genome-wide techniques aiming at the identification of relevant methylated promoters. Methods and applications allowing clinicians to monitor the methylation of target genes will be also reviewed. [less ▲]

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See detailDynamics of the negative thermal expansion in tellurium based liquid alloys
Otjacques, C.; Raty, Jean-Yves ULg; Coulet, M-V et al

in Physical Review Letters (2009), 103(24), 2459014-24590142459014

Negative thermal expansion (NTE) in tellurium based liquid alloys (GeTe 6 and GeTe 12) is analyzed through the atomic vibrational properties. Using neutron inelastic scattering, we show that the ... [more ▼]

Negative thermal expansion (NTE) in tellurium based liquid alloys (GeTe 6 and GeTe 12) is analyzed through the atomic vibrational properties. Using neutron inelastic scattering, we show that the structural evolution resulting in the NTE is due to a gain of vibrational entropy that cancels out the Peierls distortion. In the NTE temperature range, these competing effects give rise to noticeable changes in the vibrational density of states spectra. Additional first principles molecular dynamics simulations emphasize the role of the temperature dependance of the Ge atomic environment in this mechanism. For comparison, we extended our study to Ge 2Sb 2Te 5 and Ge 1Sb 2Te 4 phase-change materials. [less ▲]

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See detailCumulate origin and polybaric crystallization of Fe-Ti oxide ores in the Suwalki anorthosite, northeastern Poland
Charlier, Bernard ULg; Namur, Olivier ULg; Duchesne, Jean Clair et al

in Economic Geology (2009), 104

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See detailMario Vargas Llosa y la ficción del indigenismo
Vanden Berghe, Kristine ULg

in Houvenaghel, Eugenia; Logie, Ilse (Eds.) Alianzas entre historia y ficción. Homenaje a Patrick Collard (2009)

En numerosas novelas, Vargas Llosa aborda los mismo temas que en sus ensayos de manera que se establecen ecos entre ficción y no ficción, ecos que, de una u otra manera, apoyan implícitamente la verdad de ... [more ▼]

En numerosas novelas, Vargas Llosa aborda los mismo temas que en sus ensayos de manera que se establecen ecos entre ficción y no ficción, ecos que, de una u otra manera, apoyan implícitamente la verdad de los textos literarios por la de los ensayos historiográficos. También el hecho de que el narrador en sus novelas a menudo tenga rasgos autobiográficos evidentes de su autor contribuye a borrar las fronteras entre universo de ficción interno y universo externo. Además, en varias novelas Vargas Llosa tiende a borrar las fronteras entre los géneros, y acerca la novela al ensayo Al comparar El hablador, novela que publicó en 1987, con el ensayo José María Arguedas o las ficciones del indigenismo, de 1996, nos interrogamos acerca de la relación que existe entre las ideas sobre el indigenismo expresadas por Vargas Llosa en la ficción y fuera de ella. [less ▲]

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See detailCaractérisation de l’induction de mécanismes de défense et de l’émission de sémiochimiques chez Solanum lycopersicum L. en réponse à la présence de miellat
De Clerck, Caroline ULg

Master's dissertation (2009)

Le miellat est une substance épaisse et collante rejetée sur les feuilles et au pied de la plante-hôte par les pucerons pour éliminer l’excédent de sucres qu’ils consomment. Des travaux récents ont montré ... [more ▼]

Le miellat est une substance épaisse et collante rejetée sur les feuilles et au pied de la plante-hôte par les pucerons pour éliminer l’excédent de sucres qu’ils consomment. Des travaux récents ont montré qu’en plus des sucres et des acides aminés, le miellat contenait plusieurs souches bactériennes. L’objectif de ce travail est de déterminer si cette excrétion des pucerons possède un pouvoir éliciteur, à savoir si elle est capable de provoquer une réaction de défense de la part de la plante, ce qui la rendrait plus résistante à des attaques ultérieures. Pour ce faire, différentes étapes dans la mise en place des défenses chez la plante ont été ciblées. Une alcalinisation du milieu extracellulaire chez des cellules de tabac a été observée, essentiellement provoquée par la bactérie S. sciuri contenue dans le miellat. Les résultats permettent également de suspecter une action combinée de la bactérie avec un ou plusieurs de ses métabolites. La mise en présence de plantes entières traitées avec du miellat et du champignon pathogène B. cinerea a permis d’observer une meilleure résistance des plantes traitées. De plus, des cellules de tabac mises en présence de la bactérie S. sciuri montrent une forte mortalité, sans doute due à une réponse hypersensible. Des essais de chémiluminescence et de prélèvement de molécules volatiles ont été réalisés afin de confirmer ces observations mais n’ont donné aucun résultat significatif. Il est donc difficile de conclure, sur base de ces résultats, à l’existence d’un réel pouvoir éliciteur du miellat. Au vu des premiers résultats obtenus ici et afin de les affiner, d’autres techniques plus sensibles devraient être utilisées. [less ▲]

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See detailComment on "Electronic structure and zone-center phonon modes in multiferroic bulk BiFeO3" [J. Appl. Phys. 103, 083712 (2008)]
Hermet, Patrick ULg; Goffinet, Marco ULg; Ghosez, Philippe ULg

in Journal of Applied Physics (2009), 105

In a recent paper, Tutuncu and Srivastava [J. Appl. Phys. 103, 083712 (2008)] report the electronic structure and the assignment of the zone-center phonon modes of the R3c phase of BiFeO3 using the ... [more ▼]

In a recent paper, Tutuncu and Srivastava [J. Appl. Phys. 103, 083712 (2008)] report the electronic structure and the assignment of the zone-center phonon modes of the R3c phase of BiFeO3 using the density functional theory. In the present comment, we point out some physical inaccuracies in their mode assignment. We review their interpretation and analyze which conclusions are actually justified. [less ▲]

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See detailLes défauts d'implantation placentaire et leurs conséquences sur la fonction endothéliale maternelle
Foidart, Jean-Michel ULg; Noël, Agnès ULg; Chantraine, Frédéric ULg et al

in Bulletin Académique National de Médecine (2009), 193(5), 1059-66

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See detailSiGe growth using Si3H8 by low temperature chemical vapor deposition
Takeuchi, Shotaro; Nguyen, Ngoc Duy ULg; Goossens, Jozefien et al

in Thin Solid Films (2009), 518(6), 18

Low temperature epitaxial growth of group-IV alloys is a key process step to realize the advanced Si-based devices. In order to keep high growth rate below 600 $\,^ rc$C, trisilane (Si3H8) was used for ... [more ▼]

Low temperature epitaxial growth of group-IV alloys is a key process step to realize the advanced Si-based devices. In order to keep high growth rate below 600 $\,^ rc$C, trisilane (Si3H8) was used for their growth as an alternative Si precursor gas. Then, we compared the use of Si3H8 versus SiH4 for Si1−xGex growth in H2 and N2 as carrier gas by low temperature chemical vapor deposition. By using Si3H8 and controlling GeH4 flow rate, Si1−xGex growth with high growth rate and wide range of Ge concentration has been achieved compared to SiH4-based process. The growth rate and Ge concentration in Si1−xGex with Si3H8 grown at 600 $\,^ rc$C ranged from 11 to 74 nm/min and from 0 to 40%, respectively. The obtained growth rates with Si3H8 are between 1.5 and 6 times higher than for SiH4 at a given growth condition. Si3H8-based in-situ B- and C-doped Si1−xGex growth with high growth rate was also demonstrated [less ▲]

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See detailL'environnement, nouveau facteur de migrations ?
Gemenne, François ULg

in Jaffrelot, Christophe; Lequesne, Christian (Eds.) L'Enjeu Mondial: Les Migrations (2009)

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See detailPolitiques de la souffrance, politiques du vivant : quand les corps « parlent » de la souffrance
Vrancken, Didier ULg

in Perilleux, Thomas; Cultiaux, John (Eds.) Destins politiques de la souffrance. Intervention sociale, justice, travail (2009)

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See detail30 and 43 months period cycles found in air temperature time series using the Morlet wavelet
Nicolay, Samuel ULg; Mabille, Georges ULg; Fettweis, Xavier ULg et al

in Climate Dynamics (2009), 33

A wavelet-based methodology is applied to relevant climatic indices and air temperature records and allow to detect the existence of unexpected cycles. The scale spectrum shows the presence of two cycles ... [more ▼]

A wavelet-based methodology is applied to relevant climatic indices and air temperature records and allow to detect the existence of unexpected cycles. The scale spectrum shows the presence of two cycles of about 30 and 43 months, respectively, in the air–temperature time series, in addition to the well-known cycles of 1 day and 1 year. The two cycles do not affect the globe uniformly: some regions seem to be more influenced by the period of 30 months (e.g. Europe), while other areas are affected by the period of 43 months (e.g. North-West of the USA). Similar cycles are found in the indices and the regions influenced by these indices: the NAO index and the Western Europe display a cycle of 30 months, while the cycle of 43 months can be found in the ENSO index and in regions where it is known to have an impact. [less ▲]

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See detailUnderstanding of optical readout accuracy with micromechanical sensor cantilever monitored by surface plasmon resonanc
Hastanin, Juriy ULg; Renotte, Yvon ULg; Fleury-Frenette, Karl ULg et al

in Optics Communications (2009), 282

This paper reports a concept of micromechanical sensing of environmental condition using the surface plasmon resonance phenomenon. We calculate the resolution in the cantilever bending monitoring using ... [more ▼]

This paper reports a concept of micromechanical sensing of environmental condition using the surface plasmon resonance phenomenon. We calculate the resolution in the cantilever bending monitoring using the transfer matrix numerical method. We show that the cantilever deflection can be monitored with a resolution in the nanometer range. The SPs resonance behavior of the multilayer stack in the case of gold cantilever is discussed. We believe that this concept permits a low cost and ease of fabrication for a large bi-dimensional array of sensors with an enhanced signal-to-noise ratio. [less ▲]

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See detailGamma interferon production correlates negatively with plasma levels of pregnancy-associated glycoprotein-1 (PAG-1) during gestation in dairy cows naturally infected with Neospora caninum
Lopez-Gatius, F.; Almeria, S.; Yániz, J. L. et al

in O’Leary, M.; Arnett, J. (Eds.) Pregnancy Protein Research (2009)

Gamma interferon (IFN-γ) production has been ascribed a role in protecting cows infected with Neospora caninum against abortion. The present study analyzes the interaction between IFN-γ production and ... [more ▼]

Gamma interferon (IFN-γ) production has been ascribed a role in protecting cows infected with Neospora caninum against abortion. The present study analyzes the interaction between IFN-γ production and levels of plasma pregnancy-associated glycoprotein-1 (PAG-1), as a marker of placental/fetal well-being, throughout gestation in naturally Neospora-infected dairy cows. Data were obtained from 88 pregnant cows from two herds: 62 seropositive and 26 seronegative for the parasite. Blood sample collection was performed on days 40, 90, 120, 150, 180 and 210 of gestation. Plasma was tested for antibodies against N. caninum, PAG-1 and IFN-γ. Twenty five (28.4%) pregnancies were recorded after AI using Holstein-Friesian semen (19 in seronegative and 6 in seropositive animals), and 63 (71.6%) after AI using Limousin semen (7 in seronegative and 56 in seropositive animals). Gamma interferon was detected in the plasma of 14 (22.6%) of the 62 Neospora-seropositive cows and could not be detected in any of the 26 seronegative animals. All 14 cows producing IFN-γ became pregnant by using Limousin semen. Our GLM repeated measures showed no effect of herd, lactation number, milk production at the time of pregnancy diagnosis and Neospora-seropositivity on plasma PAG-1 concentrations. Significant positive effects of both the day of gestation (P<0.0001) and interaction between day of gestation and breed of sire (P = 0.001) on PAG-1 values were registered. Cows carrying twins had higher (P = 0.002) PAG-1 concentrations throughout gestation than cows carrying singletons. Interactions between breed of sire and Neospora-seropositivity (P<0.0001), and between IFN-γ production and Neospora-seropositivity (P = 0.04) were also detected. Thus, Neospora-seronegative cows inseminated with Limousin and Neospora-seropositive cows with no IFN-γ production, exhibited higher PAG-1 concentrations throughout gestation than seropositive cows inseminated with Limousin semen and producing IFN-γ, respectively. Our data indicate that production of IFN-γ correlates negatively and, the production of antibodies against N. caninum is uncorrelated with plasma PAG-1 concentrations during gestation in Neospora-infected dairy cows. Our results also suggest that augmented Th1 cell-mediated immunity is related to a lower risk of abortion and therefore higher resistance to the parasite in cows inseminated with Limousin versus Holstein-Friesian semen. [less ▲]

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See detailMutation des systèmes partisans et résultats électoraux : Proportion congrue et gouvernabilité
Verjans, Pierre ULg

in Matagne, Geoffroy; Beaufays, Jean (Eds.) La Belgique en mutation : Systèmes politiques et politiques publiques (1968-2008) (2009)

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See detailDe rol van de magistratuur in herstelgerichte praktijken
Aertsen, Ivo; Lauwaert, Katrien ULg

in Tijdschrift voor Herstelrecht (2009), 9(2), 38-51

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