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See detailImpact of poplar trees on the soil water dynamics of a maize field in West-Flanders
Coussement, Tom; Janssens, Pieter; Elsen, Annemie et al

Conference (2017, February 15)

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See detailDevelopment and implementation of a methodology for hybrid fire testing applied to concrete structures with elastic boundary conditions
Sauca, Ana ULg

Doctoral thesis (2017)

Fire tests remain a precious tool to comprehend the behavior of structures under accidental fire conditions. The common practice in fire testing is to isolate the tested element in a furnace in which the ... [more ▼]

Fire tests remain a precious tool to comprehend the behavior of structures under accidental fire conditions. The common practice in fire testing is to isolate the tested element in a furnace in which the mechanical support conditions are maintained constant throughout the test. However, such tests fail to capture the effect of the structure surrounding the element of interest when this effect cannot be realistically modeled by a free or fixed support condition. It has been observed in large-scale tests that the behavior of entire structures under fire is different compared with the behavior observed in traditional tests on isolated elements. This indicates the importance of capturing accurately the boundary conditions between the element and the remainder of the structure when characterizing the behavior of this element in fire. The literature describes a few attempts at performing fire tests under realistic boundary conditions. In the latter, the tests were still performed on isolated elements but the boundary conditions were updated during the test taking into account the characteristics of the remainder structure. This technique, called hybrid testing, represents an appealing solution to test structural elements under realistic boundary conditions. Hybrid testing is a methodology which offers the advantage of testing singular structural elements (or a group of structural elements) named physical substructure PS while at the same time considering the characteristics of the remainder substructure named numerical NS, thus allowing to model realistic boundary conditions. Pioneering work has been done in the seismic field where this technique is now well described, but the implementation of this methodology for structural fire testing raises important challenges due to the specificities of the field. A few hybrid fire tests have been performed in the past on columns and slabs. Their analysis shows that they all use a similar methodology, which is referred to as the first generation method in this work. The objective of the thesis was to develop and implement a hybrid fire testing methodology on a reinforced concrete beam extracted from a moment resisting frame. Initially, it was intended to build on the first generation method, but after its detailed analysis in the development stage it has been observed that the process can be unstable. The value of the stiffness ratio between the numerical substructure and the physical substructures has been identified as critical in governing the stability of the test, dictating whether the hybrid test needs to be applied in displacement control or force control. This is a severe drawback of the first generation method, as the stiffness ratio is unknown and changing during the test; besides different degrees-of-freedom can require different procedures during the test. Therefore, it has been shown that the first generation method should not be applied as it can lead to instability prematurely during the tests. To overcome the drawbacks of the first generation method, the objective was to develop a new technique that leads to interface equilibrium and compatibility while at the same time is unconditionally stable (i.e. independently of the stiffness ratio). Thus a novel methodology was developed and applied to the case of a concrete beam (PS) being part of a concrete moment resisting frame (NS). The novel method makes use of the PS’s stiffness in addition to the NS’s stiffness as it was the case in the first generation method. The stiffness matrix of the PS is unknown during the test therefore the initial tangent stiffness matrix is considered during the calculations. The latter choice influences the value of the time step to be adopted during the test. Every time step the boundary conditions are updated and it will be discussed how the chosen value can influence the results. A predetermined matrix is used to describe the behavior of the NS during the hybrid fire tests. This approach does not capture the nonlinearity of the remainder but at the same time the implementation is relative simple and the negative effect of the time calculation is eliminated. The procedure to compute the predetermined matrix of the NS is presented in this thesis. One possible direction in the future development of hybrid fire testing is to model the NS in the finite element model. The algorithm of the proposed method is developed and implemented in nonlinear finite element software SAFIR in order to perform virtual hybrid fire tests. The same algorithm is translated in order to be implemented by the company in charge of the control system at the CERIB furnace facility. The thesis also presents a traditional fire test that has been performed on the beam, in order to highlight the differences when testing structural element without and with the real boundary conditions. For the hybrid test, three degrees-of-freedom are controlled at the interface. The furnace facility has an important role to perform successful test where the equilibrium and compatibility are ensured and no instability occurs during the test. The impediments encountered during the tests will be discussed along with the recommendation for a successful hybrid fire test. [less ▲]

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See detailPerfectly matched layers for convex truncated domains with discontinuous Galerkin time domain simulations
Modave, Axel; Lambrechts, Jonathan; Geuzaine, Christophe ULg

in Computers & Mathematics with Applications (2017), 73(4), 684-700

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See detailL’énonciation visuelle entre réflexivité et métalangage
Dondero, Maria Giulia ULg

in Moutat, Audrey; Dondero, Maria Giulia; Beyaert-Geslin, Anne (Eds.) Les plis du visuel. Réflexivité et énonciation dans l’image (2017)

Ce texte vise tout d’abord à illustrer l’hypothèse selon laquelle le langage verbal n’est pas le traducteur unique et universel de toutes les sémiotiques (visuelles, musicales, audiovisuelles, etc.) comme ... [more ▼]

Ce texte vise tout d’abord à illustrer l’hypothèse selon laquelle le langage verbal n’est pas le traducteur unique et universel de toutes les sémiotiques (visuelles, musicales, audiovisuelles, etc.) comme l’affirment la sémiologie de Roland Barthes et l’approche linguistique. Nous comparons ensuite la notion de réflexivité à celle de métalangage : si les études sur la réflexivité sont assez répandues dans plusieurs disciplines concernant l’image dont en histoire de l’art, il n’en est pas de même pour la notion de métalangage qui implique généralement la hiérarchie d’un langage sur l’autre. Nous prenons en considération à ce propos les critiques des détracteurs de la possibilité d’envisager un métalangage visuel qui s’appuient sur la conviction que le langage visuel n’a pas d’alphabet ni de grammaire stables, voire qu’il est démuni d’unités morphologiques ainsi que de règles syntaxiques. Nous illustrons brièvement des tentatives de construire un alphabet d’unités visuelles, telle que celle de Paul Klee, et nous passons en revue des concepts opérationnels qui permettent de concevoir en image une dimension méta et notamment celui de « semi-symbolisme » selon A.J. Greimas et J.-M. Floch ainsi que celui de « pli » chez Ch. Metz. [less ▲]

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See detailTRIFOCAL INTRAOCULAR LENS WITH EXTENDED RANGE OF VISION AND CORRECTION OF LONGITUDINAL CHROMATIC ABERRATION
Pagnoulle, Christophe; Redzovic, Suad; Voisin, Laure et al

Patent (2017)

The present invention relates to an intraocular lens, and in particular to an intraocular lens with three focal points and a diffractive profile on an anterior or posterior face. This lens provides ... [more ▼]

The present invention relates to an intraocular lens, and in particular to an intraocular lens with three focal points and a diffractive profile on an anterior or posterior face. This lens provides extended range of vision (EROV) from far to near distance and reduces linear chromatic aberration (LCA). [less ▲]

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See detailRéflexions pour une anti-pédagogie publique et un chahut endémique : renversement du rapport maître-élève
Franck, Thomas ULg

Conference given outside the academic context (2017)

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See detailThe desire of parenthood: intuitive co-parental behaviors and quality of couple relationship among Italian and Belgian same-sex and opposite-sex couples.
Miscioscia, Marina ULg; Blavier, Adelaïde ULg; Pagone, Paolo et al

in Frontiers in Psychology (2017), 8(110),

Studies that focused on family issues have allowed a great understanding of the aspectsrelated to its subsystems, such as parenting desire and its expectations, couples’satisfaction and quality of child’s ... [more ▼]

Studies that focused on family issues have allowed a great understanding of the aspectsrelated to its subsystems, such as parenting desire and its expectations, couples’satisfaction and quality of child’s outcomes. All these aspects are greatly interconnectedand contribute to the creation of specific family dynamics, such as the quality offamily interactions. The present study focuses on intuitive co-parental behaviors andthe quality of couple relationship observed during the decision process (intention anddesire) to be (or become) parents. Our first goal was to explore these aspects ina cross-national sample made of Italian and Belgian heterosexual, lesbian and gaycouples. We then aimed to evaluate if the degree of internalized homophobia affectsco-parental alliance. The quality of couple relationship and co-parental behaviors havebeen evaluated through the recruitment of a group of 115 stable heterosexual, gay andlesbian couples (230 individuals, 20–50 years of age) without children, who wanted tobecome parents. We used the Prenatal Lausanne Trilogue Play to evaluate the Co-parental Alliance; the couple’s satisfaction was assessed with the Dyadic AdjustmentScale and the Internalized Homophobia with the MISS-LG. In line with the existentliterature, the analysis did not find any difference between lesbian, gay and heterosexualcouples in terms of co-parental alliance. High levels of couple adjustment lead to betterparental performances among both Italian and Belgian couples. The results suggestalso that sexual stigma differs from one country to another, and it has an impact on thecapability of managing co-parenting. Clinical implications should be verified in furtherlongitudinal studies in order to observe the impact on the inter-generational transmissionof psychopathology. [less ▲]

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See detailL’habit fait-il le moine ? Le confesseur du Gouverneur des Pays-Bas espagnols (XVIIe siècle)
Pirlet, Pierre-François ULg

Conference given outside the academic context (2017)

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See detailMagnetocaloric Properties of Zinc-Nickel Ferrites Around Room Temperature
El Maalam, Khadija; Fkhar, lahcen; Mohammed, Hamedoun et al

in Journal of Superconductivity and Novel Magnetism (2017)

In this paper, structural, magnetic, and magnetocaloric properties of zinc-doped nickel ferrite, Zn1−xNixFe2O4 (x = 0.3 and 0.4) were investigated. The samples were prepared using solid-state reaction. X ... [more ▼]

In this paper, structural, magnetic, and magnetocaloric properties of zinc-doped nickel ferrite, Zn1−xNixFe2O4 (x = 0.3 and 0.4) were investigated. The samples were prepared using solid-state reaction. X-ray diffraction (XRD) and magnetization measurements were performed to study crystallographic structure and magnetic properties. For a magnetic field changing from 0 to 5 T, the corresponding isothermal entropy change was found to be near 1.4 J/kg K for both samples. The decreasing of Ni content from x = 0.4 to 0.3, enables to shift the Curie temperature of Zn1−xNixFe2O4 from 450 K toward (325 K). As main results, it was found that the relative cooling power (RCP) could be significantly enhanced by changing Ni concentration in Zn1−xNixFe2O4 (505 J/kg (for x = 0.3) and 670 J/kg (for x = 0.4)), which is considered as a recommended parameter for a wide temperature range in magnetic refrigeration application. Our finding should inspire and open new ways for the enhancement of the magnetocaloric effect in spinel ferrite-based materials. [less ▲]

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See detailTendances globales, besoins locaux et réponses des politiques de développement rural en Wallonie, Belgique
Dogot, Thomas ULg

Conference given outside the academic context (2017)

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See detailMulti-evaporator air-conditioning system
Gillet, Thomas ULg; Lemort, Vincent ULg; Andres, Emmanuelle et al

Conference (2017, February 14)

Regulation in terms of greenhouse gas emissions becomes more and more stringent and the fuel consumption targets decrease. In order to meet these demands, vehicle electrification has increased over the ... [more ▼]

Regulation in terms of greenhouse gas emissions becomes more and more stringent and the fuel consumption targets decrease. In order to meet these demands, vehicle electrification has increased over the last decade. With the arrival of plug-in hybrids and battery electric vehicles, efficient battery cooling system becomes a necessity and has to be integrated into the vehicle thermal management. One of the possibility is to integrate a chiller in the air conditioning system for extreme operating points. Moreover, this kind of system can be dedicated to luxury or large passenger cars for which a secondary evaporator is present to guarantee the comfort for rear passengers. The main challenge of this air-conditioning architecture is to maintain simultaneously the cabin thermal comfort via one or two evaporators on one hand and to maintain the battery cells in an ideal temperature range on the other hand. [less ▲]

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See detailBest Practices for NZEB design in Mixed & Cooling Dominated Climates
Attia, Shady ULg

in HARPUTLUGİL, Timuçin (Ed.) Symposium for Improving Energy Efficiency in Buildings Project (2017, February 14)

High performance buildings including net zero energy buildings (NZEB) are facing difficulty to become market mainstream in warm and hot climates. Beside the economic there are serious technical and design ... [more ▼]

High performance buildings including net zero energy buildings (NZEB) are facing difficulty to become market mainstream in warm and hot climates. Beside the economic there are serious technical and design challenges that hampers design teams design, construct and operate NZEB in mixed and cooling dominated climates. There is a difficulty to make the Passive House standard cross the heating dominated climatic zones in Northern and Central Europe to get implemented in mixed or cooling dominated climates as an ultra-energy efficient building concept. There is a need for setting new climate adaptive energy efficiency target metrics for NZEBs in warm and hot climates. This paper presents guidance and recommendations on the necessary performance target metrics for NZEBs and makes them explicit. Results are based on cross analysis of several case studies, presenting an overview of challenges and providing recommendations based on available empirical evidence to further lower those barriers Worldwide with a focus on the European construction sector. By defining the performance thresholds for NZEBs including the metrics we offer design team the possibility of verification and design assessment during early design decision making phases to instil a kind of practical, evidence based and quantifiable guidance for high performance buildings and in particular NZEBs. [less ▲]

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See detailJuno and the first UVS results from PJ1
Bonfond, Bertrand ULg

Scientific conference (2017, February 14)

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See detailThe interplay of regional systems of innovation, strategic alliances and open innovation
Segers, Jean ULg

Doctoral thesis (2017)

Modern biotechnology is a driving force and a full grown industry in the international economy with ongoing and rapid innovations. The emphasis of this dissertation is on the valorization of red biotech ... [more ▼]

Modern biotechnology is a driving force and a full grown industry in the international economy with ongoing and rapid innovations. The emphasis of this dissertation is on the valorization of red biotech, i.e. pharmaceutical and healthcare applications. Belgium has firmly established itself as an international red biotechnology country, with a world class biotechnology industry in the Flanders and Wallonia bioRegions. Developing a domestic biotechnology industry - and hence new biotechnology firms - can be influenced by regional policy. The pharmaceutical-biotechnology regional and sectoral innovation system is characterized as an international and dynamic network architecture involving numerous players engaged in drug discovery. Regional governments and dedicated public and private network organizations have supported emerging new biotechnology firms by providing critical resources and by promoting an institutional environment that has enabled partnerships between universities, highly specialized research centers, small science based academic spin-offs and corporate spin-outs and large global pharmaceutical companies. Both policy and big firms look at the new biotechnology firms from a strategic point of view. The policy objective is the emergence of new and sustainable firms in the region; the big firms objective is the filling or renewal of the pipelines of products. New biotechnology firms are both beneficiaries and targets of strategic partnering alliances with large and global (bio)pharmaceutical companies. A number of the Belgian new biotechnology firms hold a nodal position as “ most preferred partner ” with multiple alliances in dynamic R&D networks. They have a high degree of integration into global technological networks through strategic alliances. Strategic alliances and open innovation are commonly leveraged. Despite their small size and relative immaturity, some of the new biotechnology firms are able to adopt innovative business models by providing R&D and services to large biopharmaceutical companies and by cooperating with them through open innovation. [less ▲]

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See detailReforming of toluene formed during the gasification of biomass with alumina based catalysts prepared by aqueous sol-gel processes
Claude, Vincent ULg

Doctoral thesis (2017)

Summary in english: The gasification of biomass into bio-syngas (CO+H2) usually goes along with the formation of tars (toluene, naphthalene) which can cause technical problems at the outlet of the reactor ... [more ▼]

Summary in english: The gasification of biomass into bio-syngas (CO+H2) usually goes along with the formation of tars (toluene, naphthalene) which can cause technical problems at the outlet of the reactor. The reforming of these tars via primary catalysts (inside the reactor) or secondary catalysts (outside the reactor) currently appears as the most interesting way from practical and economical point of views. The use of catalysts made of metallic nanoparticles deposited on y-Al2O3 is an efficient combination for tar reforming applications. During this project, an aqueous sol-gel method for the synthesis of y-Al2O3 supports is developed. In the aim of developing catalysts with metallic nanoparticles finely dispersed, supports of y-Al2O3 are modified with a functionalized silicon precursor (3-(2-aminoethylamino)propyltrimethoxysilane, EDAS). The addition of EDAS modifies the properties of y-Al2O3. Samples prepared with other silicon precursors (non-functionalized or functionalized with other chains than the ones of EDAS) highlight that the reactivity of the precursor influences the crystallinity of the support. The presence of a functionalized chain modifies the shape of the crystallites, which leads to a narrower pore size distribution centered on 4 nm and to a higher specific surface area of the support. In order to orientate the project towards the development of either primary or secondary catalysts, catalytic tests are performed with 8000 ppmv of toluene under primary conditions (T = 750-850 °C) with either y-Al2O3 or olivine supports, doped with either 2 wt. % Ni or 10 wt. % Fe. The olivine, known as primary catalyst of reference, shows better performances. In the case of y-Al2O3, the low loading of Ni leads to the formation of a spinel of NiAl2O4 which shows low reducibility, and the doping with Fe favors the y-Al2O3 to a-Al2O3 phase transition of the support. Therefore, the next studies focuse on the development of 10 wt. % Ni/y-Al2O3 catalysts tested in secondary conditions. The reduction of catalysts entirely composed of NiAl2O4 only starts at T = 680 °C during H2- TPR measurements. However, these samples are reduced during the catalytic reforming of 24.000 ppmv of toluene at T = 650 °C. It is demonstrated that under these conditions, toluene is a better reducing agent than H2 or CO, and that the reduction of NiAl2O4 oxide with toluene enables its conversion with a very little formation of coke. For bulk NiO, reduced at low temperatures (T ~ 450 °C), the catalyst does not take advantage of the anti-coking effect brought by the phenomenon of special reduction by toluene, which leads to a quick deactivation of the catalyst by formation of carbon deposit. The addition of a surfactant (stearic acid) during the aqueous sol-gel synthesis efficiently modifies the morphology (mesopores, macropores) of Ni/y-Al2O3 catalysts. Despite a much higher catalytic activity, attributed to a better diffusion of the gaseous reagents, the sample shows a much higher sensibility towards deactivation by coking. It is hypothesized that this weakness is the consequence of the combination of several facts: loss of balance between the reaction rates of toluene cracking and the rates of dissociation-migration of the HO* and O* species + better reducibility of the catalyst, which avoids the phenomenon of special reduction by toluene + presence of large pores, which do not prevent the growth of filamentous carbon. A vast screening of catalysts composed of 10 % Ni/y-Al2O3 and doped with metals (Cu, Mn, Fe, Mo or Mn) or oxides (CaO, K2O, MgO or CeO2) is performed. The samples doped with Mn, Mo, Ca ou K show the most interesting catalytic activities and resistances against coking. It is to notice that, for an identical amount, the samples doped with two different elements (Co+Mo, Mn+Mo, Ca+K or Ce+K) show better catalytic performances compared to those doped with only one type of dopant. The tests of the best catalysts in long-term conditions (30 h) or in presence of H2S are promising. Hence, these catalysts might be adequate for industrial applications. Résumé français: La gazéification de biomasse en bio-syngas (CO+H2) s’accompagne généralement de formation de goudrons (toluène, naphtalène) qui peuvent causer des problèmes techniques en aval du réacteur. Le reformage de ces goudrons via un catalyseur primaire (à l’intérieur du réacteur) ou secondaire (en sortie du réacteur) apparaît actuellement comme la méthode la plus intéressante d’un point de vue pratique et économique. L’utilisation de catalyseurs constitués de nanoparticules métalliques supportées sur y-Al2O3 est une association efficace pour le reformage catalytique de goudrons. Une méthode de synthèse de support y-Al2O3 par voie sol-gel aqueuse est mise au point durant ce projet. Dans l’optique de synthétiser des catalyseurs composés de nanoparticules métalliques finement dispersées, des supports en y-Al2O3 sont modifiés avec un précurseur de silice fonctionnalisé : l’EDAS (3-(2-aminoéthylamino)propyltriméthoxysilane). L’addition d’EDAS modifie les propriétés texturales du support y-Al2O3. Des échantillons préparés avec d’autres types de précurseurs de silice (non-fonctionnalisés ou fonctionnalisés avec d’autres chaînes que celle présente dans l’EDAS) mettent en évidence le fait que la réactivité du précurseur de silice influence la cristallinité du support. La présence d’une chaîne fonctionnalisée modifie quant à elle la forme des cristallites d’alumine, menant ainsi à une distribution de taille de mésopores plus étroite et centrée à 4 nm et une plus grande surface spécifique du support. Afin de déterminer quel type de catalyseurs synthétiser (primaires ou secondaires), le reformage catalytique de 8000 ppmv de toluène en conditions primaires (T = 750-850 °C) est effectué avec des supports constitués de γ-Al2O3 ou d’olivine, dopés avec 2 % Ni ou 10 % Fe. L’olivine, catalyseur primaire de référence, présente de meilleurs résultats pour le reformage du toluène. Dans le cas de y-Al2O3, le faible dopage en Ni conduit à la formation d’un spinelle NiAl2O4 difficile à réduire, et le dopage avec Fe favorise la transition de phase de y-Al2O3 vers a-Al2O3. Les travaux suivants sont donc axés sur le développement de catalyseurs de type 10 % Ni/y-Al2O3 testés en conditions secondaires. La réduction de catalyseurs constitués d’une unique phase de NiAl2O4 ne s’initie qu’à partir de T = 680 °C lors de mesures en température programmée sous H2 (TPR). Cependant, ceux-ci sont réduits lors du reformage catalytique de 24.000 ppmv de toluène à T = 650 °C. Il est démontré que dans ces conditions, le toluène est un meilleur agent réducteur que H2 ou CO, et que la réduction des espèces NiAl2O4 par le toluène permet de convertir celui-ci en syngas tout en prévenant la formation de coke. Lors de la présence de NiO réduit à plus basse température (T ~ 450 °C), le catalyseur ne tire pas avantage du phénomène de réduction spécial des oxydes métalliques par le toluène, ce qui entraîne ainsi la désactivation rapide du catalyseur par cokage. L’ajout d’un surfactant (acide stéarique) lors de la préparation par voie sol-gel aqueuse s’avère efficace afin de modifier la morphologie (mésopores, macropores) de catalyseurs Ni/y-Al2O3. Malgré une activité catalytique nettement plus élevée, attribuée à une meilleure diffusion des réactifs, l’échantillon montre des tendances beaucoup plus importantes à se désactiver par cokage. On émet l’hypothèse que cette faiblesse est due à une combinaison de plusieurs faits: déséquilibre entre la réaction de cracking du toluène et les réactions de dissociation-migration des espèces HO* et O* + meilleure réductibilité empêchant de tirer avantage du phénomène de réduction spécial par le toluène + présence de larges pores ne restreignant pas la croissance de carbone filamentaire. Un large screening de catalyseurs 10 % Ni/y-Al2O3 dopés avec des métaux (Cu, Mn, Fe, Mo ou Mn) ou des oxydes (CaO, K2O, MgO ou CeO2) est effectué. Les échantillons contenant les éléments Mn, Mo, Ca ou K s’avèrent les plus intéressants de par leur activité catalytique et leur résistance au cokage. Pour une même quantité massique ajoutée, les échantillons constitués d’associations de dopants (Co+Mo, Mn+Mo, Ca+K ou Ce+K) affichent de meilleures performances catalytiques que ceux effectués avec un seul dopant. Les résultats obtenus avec les meilleurs catalyseurs lors de tests catalytiques de longue durée (30 h) ou en présence de H2S sont prometteurs. Ceci porte à croire que ces catalyseurs pourraient convenir à une application industrielle. [less ▲]

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See detailL'ocytocine et la biologie du coup de foudre
Geenen, Vincent ULg

Conference given outside the academic context (2017)

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See detailComputational models and probabilistic methods to improve infrastructure resilience to fire
Gernay, Thomas ULg

Scientific conference (2017, February 13)

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See detailUse of primary and secondary polyvinylamines for efficient gene transfection
Dréan, Mathilde; Debuigne, Antoine ULg; Gonçalves, Christine et al

in Biomacromolecules (2017), 18(2), 440-441

Gene transfection with polymeric carrier remains a challenge, particularly high transfection levels combined with low toxicity are hard to achieve. We herein revisit polyvinylamines, an old and neglected ... [more ▼]

Gene transfection with polymeric carrier remains a challenge, particularly high transfection levels combined with low toxicity are hard to achieve. We herein revisit polyvinylamines, an old and neglected family of cationic polymers. They can be readily obtained by controlled hydrolysis of polyvinylamides prepared through (controlled) radical polymerization. A series of tailor-made and well-defined polyvinylamines bearing primary amino groups, and poly(N- methylvinylamine) bearing secondary amines, were evaluated for the transfection of cells with pDNA as a function of their molar mass, molar mass distribution and degree of deacetylation. Unexpected high transfection levels, in combination with low cytotoxicity were recorded for both series. Surprisingly, a great impact of the molar mass was observed for the primary amine polyvinylamine series, whereas the results were mostly independent on molar mass or dispersity for the polymer bearing secondary amine. It was further established that a certain percentage of acetamide groups increased the transfection level, while maintaining low cytotoxicity. These results highlight for the first time the real potential of polyvinylamines as gene carriers, and make these polymers very attractive for further development in gene therapy. [less ▲]

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