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See detailOrganocatalytic coupling of CO2 with oxetane
Alves, Margot ULg; Grignard, Bruno ULg; Boyaval, Amélie ULg et al

in ChemSusChem (2017), 10(6), 1128-1138

The organocatalytic coupling of CO2 with oxetanes is investigated under solvent-free conditions. The influence of the main reaction parameters (type of organocatalytic system, pressure and temperature) on ... [more ▼]

The organocatalytic coupling of CO2 with oxetanes is investigated under solvent-free conditions. The influence of the main reaction parameters (type of organocatalytic system, pressure and temperature) on the yield, the product formed and the selectivity of the reaction are discussed. An onium salt combined with a fluorinated alcohol promotes the efficient and selective organocatalytic synthesis of α,ω-hydroxyl oligocarbonates by coupling CO2 with oxetanes at 130 °C and at a CO2 pressure as low as 2 MPa. NMR characterizations were correlated with MALDI-ToF analyses for elucidating the structure of the oligomers. Online FTIR studies under pressure, NMR titrations and DFT calculations allowed an in-depth understanding of the reaction mechanism. Finally, CO2- based poly(carbonate-co-urethane)s were synthesized by step- growth polymerization of hydroxyl telechelic oligocarbonates with MDI. The organocatalytic system described in this paper constitutes an innovative sustainable route to the selective preparation of hydroxyl telechelic carbonates, of high interest for many applications, notably for the polyurethane business, especially for coatings or foams. [less ▲]

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See detailOrganocatalytic coupling of CO2 with a propargylic alcohol: a comprehensive study of the reaction mechanism combining in- situ ATR-IR spectroscopy and DFT calculations
Boyaval, Amélie ULg; Méreau, Raphaël; Grignard, Bruno ULg et al

in ChemSusChem (2017), 10(6), 1241-1248

The metal-free coupling of propargylic alcohols with carbon dioxide catalysed by guanidine derivatives was investigated in detail through the combination of online kinetic studies by in-situ ATR-IR ... [more ▼]

The metal-free coupling of propargylic alcohols with carbon dioxide catalysed by guanidine derivatives was investigated in detail through the combination of online kinetic studies by in-situ ATR-IR spectroscopy and DFT calculations. Bicyclic guanidines, namely TBD and MTBD, are effective catalysts for the conversion of 2-methyl-3-butyn-2-ol to α-methylene cyclic carbonate and oxoalkyl acyclic carbonate under mild reaction conditions. The lower selectivity of TBD in comparison with MTBD towards the formation of α-methylene cyclic carbonate was elucidated from DFT calculations and is related to the bifunctional activity (base/H-bond donor) of TBD decreasing the Gibbs free energy of the reaction path for the formation of the acyclic carbonate. Introduction [less ▲]

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See detailL'extrême possible. Lecture musicale de textes d'Elfriede Jelinek
Neelsen, Sarah ULg

Speech/Talk (2017)

Une sélection de textes parmi les centaines d’essais écrits par le Prix Nobel de Littérature sera présentée par Sarah Neelsen à l’occasion de la parution de son livre Les essais d’Elfriede Jelinek. Genre ... [more ▼]

Une sélection de textes parmi les centaines d’essais écrits par le Prix Nobel de Littérature sera présentée par Sarah Neelsen à l’occasion de la parution de son livre Les essais d’Elfriede Jelinek. Genre, relation, singularité (Honoré Champion 2016). Au gré d’un parcours thématique à travers une œuvre foisonnante et mal connue, ces textes parlent de la voix et des femmes, des objets du quotidien et de la peur du vide, d’enfermement et de télévision. La lecture des textes par des étudiants, comédiens et musiciens arpentera les contours du possible, tantôt dehors tantôt dedans. [less ▲]

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See detailThe Belgian election system
Bouhon, Frédéric ULg

Conference (2017, March 21)

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See detailTranscriptome analysis of pancreatic cells across distant species highlights novel important regulator genes.
tarifeno-Saldiva, estefania; Lavergne, Arnaud ULg; Bernard, Alice et al

in BMC Biology (2017), 15

Background Defining the transcriptome and the genetic pathways of pancreatic cells is of great interest for elucidating the molecular attributes of pancreas disorders such as diabetes and cancer. As the ... [more ▼]

Background Defining the transcriptome and the genetic pathways of pancreatic cells is of great interest for elucidating the molecular attributes of pancreas disorders such as diabetes and cancer. As the function of the different pancreatic cell types has been maintained during vertebrate evolution, the comparison of their transcriptomes across distant vertebrate species is a mean to pinpoint genes under strong evolutionary constrains due to their crucial function and which have preserved their selective expression in these pancreatic cell types. Results In this study, RNA-sequencing was performed on pancreatic alpha-, beta- and delta endocrine cells as well as the acinar and ductal exocrine cells isolated from adult zebrafish transgenic lines. Comparison of these transcriptomes identified many novel markers including transcription factors and signaling pathways components specific for each cell type. By performing interspecies comparisons, we identified hundreds of genes with conserved enriched expression in endocrine and exocrine cells among human, mouse and zebrafish. This list includes many genes known as crucial for pancreatic cell formation or function, but also pinpoints many factors whose pancreatic function is still unknown. A large set of endocrine-enriched genes can already be detected at early developmental stages as revealed by the transcriptomic profiling of embryonic endocrine cells, indicating a potential role in cell differentiation. The actual involvement of conserved endocrine genes in pancreatic cell differentiation was demonstrated in zebrafish for myt1b, whose invalidation leads to a reduction of alpha-cells, and for cdx4, selectively expressed in endocrine delta-cells and crucial for their specification. Intriguingly, comparison of the endocrine alpha- and beta-cell subtypes from human, mouse and zebrafish reveals a much lower conservation of the transcriptomic signatures for these two endocrine cell subtypes compared to the signatures of pan-endocrine and exocrine cells. These data suggest that the identity of the alpha- and beta-cells relies on a few key factors, corroborating numerous examples of inter-conversion between these two endocrine cell subtypes. Conclusion. This study highlights both evolutionary conserved and species-specific features that will help to unveil universal and fundamental regulatory pathways as well as pathways specific to human and laboratory animal models such as mouse and zebrafish. [less ▲]

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See detailUltimate strength of cylindrical shells with cutouts
Eui Lee, Sang; Sahin; Rigo, Philippe ULg et al

in Ships and Offshore Structures (2017)

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See detailSimultaneous synthesis and chemical functionalization of emulsion-templated porous polymers using nitroxide-terminated macromolecular surfactants
Mathieu, Kevin ULg; De Winter, Julien; Jérôme, Christine ULg et al

in Polymer Chemistry (2017), 8(11), 1850-1861

The design of functional 3D macroporous monoliths has become a necessity for a wide range of applications. Traditional post-modification strategies of porous materials are efficient but often consist in ... [more ▼]

The design of functional 3D macroporous monoliths has become a necessity for a wide range of applications. Traditional post-modification strategies of porous materials are efficient but often consist in tedious multi-steps processes. This work describes a straightforward macromolecular surfactant-assisted method for producing chemically functionalized macroporous polyHIPEs with interconnected structures. Accordingly, high internal phase emulsion-templated polymerizations were implemented in the presence of SG1-terminated amphiphilic copolymers prepared by nitroxide- mediated radical polymerization (NMP). The latter served as both stabilizers and functionalizing agents upon thermal activation of its terminal alkoxyamine and covalent anchoring of the released radical copolymer onto the walls of the scaffold. The effect of the polymerization temperature on the functionalization and openness of the final porous materials was explored. As a result, a range of open-cell styrene and acrylate-based polyHIPEs chemically grafted with PEO were obtained. Moreover, polyHIPEs were also decorated with alkyne-bearing PEO and subsequently modified via CuAAc click chemistry in order to demonstrate the potential of this macromolecular surfactants-assisted functionalization method. [less ▲]

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See detailL'extrême droite et le populisme en Europe
Debras, François ULg

Scientific conference (2017, March 21)

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See detailKNN-MDR: a learning approach for improving interactions mapping performances in genome wide association studies
Abo Al Chamlat, Sinan ULg; Farnir, Frédéric ULg

in BMC Bioinformatics (2017), 18

Background Finding epistatic interactions in large association studies like genome-wide association studies (GWAS) with the nowadays-available large volume of genomic data is a challenging and largely ... [more ▼]

Background Finding epistatic interactions in large association studies like genome-wide association studies (GWAS) with the nowadays-available large volume of genomic data is a challenging and largely unsolved issue. Few previous studies could handle genome-wide data due to the intractable difficulties met in searching a combinatorial explosive search space and statistically evaluating epistatic interactions given a limited number of samples. Our work is a contribution to this field. We propose a novel approach combining K-Nearest Neighbors (KNN) and Multi Dimensional Reduction (MDR) methods for detecting gene-gene interactions as a possible alternative to existing algorithms, e especially in situations where the number of involved determinants is high. After describing the approach, a comparison of our method (KNN-MDR) to a set of the other most performing methods (i.e., MDR, BOOST, BHIT, MegaSNPHunter and AntEpiSeeker) is carried on to detect interactions using simulated data as well as real genome-wide data. Results Experimental results on both simulated data and real genome-wide data show that KNN-MDR has interesting properties in terms of accuracy and power, and that, in many cases, it significantly outperforms its recent competitors. Conclusions The presented methodology (KNN-MDR) is valuable in the context of loci and interactions mapping and can be seen as an interesting addition to the arsenal used in complex traits analyses. [less ▲]

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See detailOils and CO2, a promising combination for designing insulating foams and high performance coatings
Detrembleur, Christophe ULg; Alves, Margot ULg; Grignard, Bruno ULg et al

Conference (2017, March 21)

Making plastics more sustainable by valorizing waste CO2 as a cheap, inexhaustible and renewable feedstock is an early stage technology with strong innovation potential that imposes itself as a strategic ... [more ▼]

Making plastics more sustainable by valorizing waste CO2 as a cheap, inexhaustible and renewable feedstock is an early stage technology with strong innovation potential that imposes itself as a strategic driver for developing future low carbon footprint materials and technologies. With a global production estimated to 18 million tons for 2016, polyurethane (PU) is one of the most important polymers in our everyday life applications (automotive, building and construction, coatings, etc.). Industrially, PU is produced by step-growth polymerization between di- or polyisocyanates and di- or polyols. However, isocyanates are toxic and drastic changes in the REACH regulations limiting/banning the use of isocyanates are expected. There is a need today to develop new greener and safer alternatives to produce PU. Valorizing CO2 as C1 feedstock for producing precursors entering in the synthesis of polyurethanes by a non-isocyanate route (NIPU) is a promising strategy to solve this challenge. In this talk, we will focus on the synthesis and characterization of novel NIPUs foams for thermal insulation, and NIPUs coatings for metal protection. Our research highlights benefit of merging bio-resources (such as vegetable oils) with carbon dioxide transformation. In the first part of this talk, we will report on the fast synthesis of bio- and CO2-sourced cyclic carbonates by coupling CO2 with epoxides using a new highly efficient bicomponent homogeneous organocatalyst under solvent-free and mild experimental conditions. The mechanism of the activation of the reaction will be discussed, and scaling up of the technology will be demonstrated (15kg scale). In the second part, we will illustrate the use of these bio- and CO2-sourced cyclic carbonates for the production of microcellular NIPU foams with closed cells morphology for thermal insulating applications, but also for preparing hybrid NIPUs coatings for metal protection. [less ▲]

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See detailInfluence of granular fraction and origin of recycled concrete aggregates on their properties
Zhao, Zengfeng ULg; Courard, Luc ULg; Michel, Frédéric ULg et al

in European Journal of Environmental and Civil Engineering (2017)

Large quantities of construction and demolition wastes are produced each year. In order to make good use of recycled concrete aggregates (RCA) in concrete, it is very important to study the influence of ... [more ▼]

Large quantities of construction and demolition wastes are produced each year. In order to make good use of recycled concrete aggregates (RCA) in concrete, it is very important to study the influence of the granular fraction and the origin of RCA on their properties. In this study, RCA from industrial produced blocks (RCA_Blocks) and slabs (RCA_Slabs) were crushed and then separated into four granular fractions (0/2, 2/6.3, 6.3/14, 14/20 mm). Each granular fraction of RCA was physically characterised. Real RCA from recycling plant were also used for comparison. The results showed that recycled sands offered significantly higher cement paste content (higher bound water content) than coarse recycled aggregates. The fine RCA had therefore a higher water absorption coefficient compared to coarser fractions of RCA. The water absorption of finer fraction of RCA could be extrapolated precisely from the relationship between water absorption and cement paste content (or bound water content) of three coarse fractions of RCA. The values of hardened cement paste content obtained for the RCA_Blocks were lower than those measured on the RCA_Slabs, which was due to a smaller amount of initial cement paste content in blocks. The results showed that RCA_Slabs were more angular than RCA_Blocks. [less ▲]

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See detailConférence-débat avec le Raoul Collectif
Cormann, Grégory ULg; Hamers, Jérémy ULg

Conference given outside the academic context (2017)

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See detailMultidisciplinary rehabilitation program after breast cancer: benefits on physical function, anthropometry and quality of life.
Leclerc, Anne-France ULg; Foidart-Dessalle, Marguerite ULg; Tomasella, Marco ULg et al

in European Journal of Physical and Rehabilitation Medicine (2017)

BACKGROUND: Different clinical trials show beneficial effects of physical training offered during and / or after breast cancer treatment. However, given the variety of side effects that may be encountered ... [more ▼]

BACKGROUND: Different clinical trials show beneficial effects of physical training offered during and / or after breast cancer treatment. However, given the variety of side effects that may be encountered, physical training could be combined with psychological, relational and social guidance. This kind of multidisciplinary program has been little studied so far. AIM: To determine the benefits of a three-month multidisciplinary rehabilitation program among women after breast cancer treatment. DESIGN: Controlled no-randomized trial. SETTING: University for outcomes, University Hospital Center for interventions. POPULATION: Two hundred and nine outpatients who have been treated for a primary breast carcinoma. METHODS: Patients were divided into a control group (n=106) and an experimental group (n=103) which has benefited from a rehabilitation program of three months including physical training and psycho-educational sessions. The assessments, performed before and after the program, included functional assessments ("Sit and Reach Test", maximal incremental exercise test and "Six-Minute Walk Test"), body composition measurements (body mass index (BMI) and body fat percentage) and a questionnaire (European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30). RESULTS: After three months, flexibility, walking distance and all parameters measured during the maximal incremental exercise, except maximal heart rate, were significantly improved in the experimental group. The body fat percentage was significantly decreased and a significant improvement was observed for perceived health status (quality of life), functional role, emotional state, physical, cognitive and social functions and for most symptoms. In the control group, most of these improvements didn't appear and a significant increase in BMI and body fat percentage was observed. CONCLUSIONS: This trial identifies the benefits of a well detailed multidisciplinary rehabilitation program, including physical re-conditioning and psycho-educational sessions, with important improvements in functional capacity, body composition and the majority of functions and symptoms among women after breast cancer treatment. CLINICAL REHABILITATION IMPACT: Through its results, this study could contribute to the development of hospital quality standards for oncologic rehabilitation. Physiotherapists can efficiently propose this kind of multidisciplinary rehabilitation program. [less ▲]

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