Last 7 days
Bookmark and Share    
Full Text
Peer Reviewed
See detailModeling pre-metastatic lymphvascular niche in the mouse ear sponge assay.
Garcia-Caballero, Melissa; Van De Velde, Maureen ULg; Blacher, Silvia ULg et al

in Scientific Reports (2017), 7

Lymphangiogenesis, the formation of new lymphatic vessels, occurs in primary tumors and in draining lymph nodes leading to pre-metastatic niche formation. Reliable in vivo models are becoming instrumental ... [more ▼]

Lymphangiogenesis, the formation of new lymphatic vessels, occurs in primary tumors and in draining lymph nodes leading to pre-metastatic niche formation. Reliable in vivo models are becoming instrumental for investigating alterations occurring in lymph nodes before tumor cell arrival. In this study, we demonstrate that B16F10 melanoma cell encapsulation in a biomaterial, and implantation in the mouse ear, prevents their rapid lymphatic spread observed when cells are directly injected in the ear. Vascular remodeling in lymph nodes was detected two weeks after sponge implantation, while their colonization by tumor cells occurred two weeks later. In this model, a huge lymphangiogenic response was induced in primary tumors and in pre-metastatic and metastatic lymph nodes. In control lymph nodes, lymphatic vessels were confined to the cortex. In contrast, an enlargement and expansion of lymphatic vessels towards paracortical and medullar areas occurred in pre-metastatic lymph nodes. We designed an original computerized-assisted quantification method to examine the lymphatic vessel structure and the spatial distribution. This new reliable and accurate model is suitable for in vivo studies of lymphangiogenesis, holds promise for unraveling the mechanisms underlying lymphatic metastases and pre-metastatic niche formation in lymph nodes, and will provide new tools for drug testing. [less ▲]

Detailed reference viewed: 17 (5 ULg)
Full Text
Peer Reviewed
See detailRationalising vitamin B6 biofortification in crop plants.
Fudge, Jared; Mangel, Nathalie; Gruissem, Wilhelm et al

in Current Opinion in Biotechnology (2017), 44

Vitamin B6 encompasses a group of related compounds (vitamers) that can only be biosynthesised de novo by plants and microorganisms. Enzymatic cofactor and antioxidant functions for vitamin B6 are ... [more ▼]

Vitamin B6 encompasses a group of related compounds (vitamers) that can only be biosynthesised de novo by plants and microorganisms. Enzymatic cofactor and antioxidant functions for vitamin B6 are established in all kingdoms. Human vitamin B6 dietary insufficiency or genetic defects in B6 vitamer interconversion result in various neurological and inflammatory pathologies with several populations at-risk or marginal for vitamin B6 status. Three (rice, wheat and cassava) of the world's top five staple crops do not meet the recommended dietary allowance for vitamin B6, when consumed as a major proportion of the diet. In addition, controlled enhancement of the appropriate B6 vitamer in crops has the potential to confer stress resistance. Thus, crop biofortification strategies represent an opportunity to reduce the risk of deficiency in populations with limited diet diversity and quality, as well as improving stress tolerance. [less ▲]

Detailed reference viewed: 23 (3 ULg)
Full Text
Peer Reviewed
See detailRegional sea level changes for the 20th and the 21st century induced by the regional variability in Greenland ice sheet surface mass loss
Meyssignac, B.; Fettweis, Xavier ULg; Chevrier, R. et al

in Journal of Climate (2017), online

Surface mass balance (SMB) variations of the Greenland ice sheet (GrIS) has been identified as an important contributor to contemporary and projected global mean sea level variations but their impact on ... [more ▼]

Surface mass balance (SMB) variations of the Greenland ice sheet (GrIS) has been identified as an important contributor to contemporary and projected global mean sea level variations but their impact on the regional sea level change pattern is still poorly known. This study provides for the first time, consistent estimates (i.e. computed with the same models over the past -1900-2015- and over the future -2015-2100-) of GrIS SMB over 1900-2100 based on the output of 32 atmospheric-ocean General Circulation Models and Earth system models involved in the Climate Model Intercomparison Project phase 5 (CMIP5). It is based on a downscaling technique calibrated against the MAR regional climate model in order to calculate an ensemble of 32 Greenland SMB estimates at regional scale. Because the GrIS SMB does not respond uniformly to greenhouse gases (GHG) emissions. the southern part of the GrIS is more sensitive to climate warming. This study shows that it should be in imbalance in the 21st century sooner that the northern part. This regional variability affects significantly the associated relative sea level pattern over the entire ocean and particularly along the eastern coast of US and the northern coast of Europe. This highlights the necessity of taking into account GrIS regional SMB changes to evaluate accurately relative sea level changes in future projections. [less ▲]

Detailed reference viewed: 26 (3 ULg)
Full Text
Peer Reviewed
See detailHigh resolution (1 km) positive degree-day modelling of Greenland ice sheet surface mass balance, 1870–2012 using reanalysis data
Wilton, D.; Jowett, A.; Hanna, E. et al

in Journal of Glaciology (2017), 63

We show results from a positive degree-day (PDD) model of Greenland ice sheet (GrIS) surface mass balance (SMB), 1870–2012, forced with reanalysis data. The model includes an improved daily temperature ... [more ▼]

We show results from a positive degree-day (PDD) model of Greenland ice sheet (GrIS) surface mass balance (SMB), 1870–2012, forced with reanalysis data. The model includes an improved daily temperature parameterization as compared with a previous version and is run at 1 km rather than 5 km resolution. The improvements lead overall to higher SMB with the same forcing data. We also compare our model with results from two regional climate models (RCMs). While there is good qualitative agreement between our PDD model and the RCMs, it usually results in lower precipitation and lower runoff but approximately equivalent SMB: mean 1979–2012 SMB (± standard deviation), in Gt a−1, is 382 ± 78 in the PDD model, compared with 379 ± 101 and 425 ± 90 for the RCMs. Comparison with in situ SMB observations suggests that the RCMs may be more accurate than PDD at local level, in some areas, although the latter generally compares well. Dividing the GrIS into seven drainage basins we show that SMB has decreased sharply in all regions since 2000. Finally we show correlation between runoff close to two calving glaciers and either calving front retreat or calving flux, this being most noticeable from the mid-1990s. [less ▲]

Detailed reference viewed: 49 (3 ULg)
Full Text
Peer Reviewed
See detailPEGylated and Functionalized Aliphatic Polycarbonate Polyplex Nanoparticles for Intravenous Administration of HDAC5 siRNA in Cancer Therapy
Frère, Antoine ULg; Baroni, Alexandra; Hendrick, Elodie ULg et al

in ACS Applied Materials and Interfaces (2017), 25(9(3)), 2181-2195

Guanidine and morpholine functionalized aliphatic polycarbonate polymers are able to efficiently deliver histone deacetylase 5 (HDAC5) siRNA into the cytoplasm of cancer cells in vitro leading to a ... [more ▼]

Guanidine and morpholine functionalized aliphatic polycarbonate polymers are able to efficiently deliver histone deacetylase 5 (HDAC5) siRNA into the cytoplasm of cancer cells in vitro leading to a decrease of cell proliferation were previously developed. To allow these biodegradable and biocompatible polyplex nanoparticles to overcome the extracellular barriers and be effective in vivo after an intravenous injection, polyethylene glycol chains (PEG750 or PEG2000) were grafted on the polymer structure. These nanoparticles, showed an average size of about 150 nm and a slightly positive zeta potential with complete siRNA complexation. Behavior of PEGylated and non-PEGylated polyplexes were investigated in the presence of serum, in terms of siRNA complexation (Fluorescence Correlation Spectroscopy), size (Dynamic Light Scattering and Single-Particle Tracking), interaction with proteins (Isothermal Titration Calorimetry) and cellular uptake. Surprisingly, both PEGylated and non-PEGylated formulations presented relatively good behavior in the presence of fetal bovine serum (FBS). Hemocompatibility tests showed no effect of these polyplexes on hemolysis and coagulation. In vivo biodistribution in mice was performed and showed a better siRNA accumulation at the tumor site for PEGylated polyplexes. However, cellular uptake in protein-rich conditions showed that PEGylated polyplex lost their ability to interact with biological membranes and enter into cells, showing the importance to perform in vitro investigations in physiological conditions closed to in vivo situation. In vitro, the efficiency of PEGylated nanoparticles decreases compared to non-PEGylated particles, leading to the loss of the antiproliferative effect on cancer cells. [less ▲]

Detailed reference viewed: 39 (8 ULg)
Full Text
Peer Reviewed
See detailExome copy number variation detection: Use of a pool of unrelated healthy tissue as reference sample
Wenric, Stéphane ULg; Sticca, Tiberio ULg; CABERG, Jean-Hubert ULg et al

in Genetic Epidemiology (2017)

An increasing number of bioinformatic tools designed to detect CNVs (copy number variants) in tumor samples based on paired exome data where a matched healthy tissue constitutes the reference have been ... [more ▼]

An increasing number of bioinformatic tools designed to detect CNVs (copy number variants) in tumor samples based on paired exome data where a matched healthy tissue constitutes the reference have been published in the recent years. The idea of using a pool of unrelated healthy DNA as reference has previously been formulated but not thoroughly validated. As of today, the gold standard for CNV calling is still aCGH but there is an increasing interest in detecting CNVs by exome sequencing. We propose to design a metric allowing the comparison of two CNV profiles, independently of the technique used and assessed the validity of using a pool of unrelated healthy DNA instead of a matched healthy tissue as reference in exome-based CNV detection. We compared the CNV profiles obtained with three different approaches (aCGH, exome sequencing with a matched healthy tissue as reference, exome sequencing with a pool of eight unrelated healthy tissue as reference) on three multiple myeloma samples. We show that the usual analyses performed to compare CNV profiles (deletion/amplification ratios and CNV size distribution) lack in precision when confronted with low LRR values, as they only consider the binary status of each CNV. We show that the metric-based distance constitutes a more accurate comparison of two CNV profiles. Based on these analyses, we conclude that a reliable picture of CNV alterations in multiple myeloma samples can be obtained from whole-exome sequencing in the absence of a matched healthy sample. [less ▲]

Detailed reference viewed: 31 (8 ULg)
Full Text
Peer Reviewed
See detailAssessing Inter- and Intramolecular Continuous-Flow Strategies towards Methylphenidate Hydrochloride
Gerardy, Romaric ULg; Winter, Marc; Vizza, Alessandra et al

in Reaction Chemistry and Engineering (2017), 2(2), 149-158

Detailed reference viewed: 17 (6 ULg)
Full Text
Peer Reviewed
See detailLe peuple et les intellectuels au Mexique. Quelques avatars d'une relatio difficile
Vanden Berghe, Kristine ULg

in Goin, Emilie; Provenzano, François (Eds.) Usages du peuple. Savoirs, discours, politiques. (2017)

Detailed reference viewed: 13 (1 ULg)
Full Text
Peer Reviewed
See detailThe role of fatty acid beta-oxidation in lymphangiogenesis.
Wong, Brian W.; Wang, Xingwu; Zecchin, Annalisa et al

in Nature (2017), 542(49),

Lymphatic vessels are lined by lymphatic endothelial cells (LECs), and are critical for health. However, the role of metabolism in lymphatic development has not yet been elucidated. Here we report that in ... [more ▼]

Lymphatic vessels are lined by lymphatic endothelial cells (LECs), and are critical for health. However, the role of metabolism in lymphatic development has not yet been elucidated. Here we report that in transgenic mouse models, LEC-specific loss of CPT1A, a rate-controlling enzyme in fatty acid beta-oxidation, impairs lymphatic development. LECs use fatty acid beta-oxidation to proliferate and for epigenetic regulation of lymphatic marker expression during LEC differentiation. Mechanistically, the transcription factor PROX1 upregulates CPT1A expression, which increases acetyl coenzyme A production dependent on fatty acid beta-oxidation. Acetyl coenzyme A is used by the histone acetyltransferase p300 to acetylate histones at lymphangiogenic genes. PROX1-p300 interaction facilitates preferential histone acetylation at PROX1-target genes. Through this metabolism-dependent mechanism, PROX1 mediates epigenetic changes that promote lymphangiogenesis. Notably, blockade of CPT1 enzymes inhibits injury-induced lymphangiogenesis, and replenishing acetyl coenzyme A by supplementing acetate rescues this process in vivo. [less ▲]

Detailed reference viewed: 27 (2 ULg)
Full Text
Peer Reviewed
See detailPercevoir et reconnaître des symboles : La théorie de la représentation iconique de Dominic Lopes
Hagelstein, Maud ULg

in Bulletin d'Analyse Phénoménologique (2017)

In his works on the epistemological value of images (Understanding Pictures — 1996), Dominic Lopes (Department of Philosophy — University of British Columbia) develops an analytical aesthetics primarily ... [more ▼]

In his works on the epistemological value of images (Understanding Pictures — 1996), Dominic Lopes (Department of Philosophy — University of British Columbia) develops an analytical aesthetics primarily concerned with iconic representation. His analysis distinguishes two models of iconic representation comprehension. In the first model, inspired by perceptual approaches like that of Richard Wollheim, the process of image recognition is rooted in perception (to sum it up: perceptualism embraces the idea of « likeness » between the image and what it represents). One of this model’s shortcomings, however, is that it too readily assumes that perception can be a natural, straightforward process. Indeed, iconic representation can not be understood through perception alone, as vision is of course influenced by cultural and, most of all, cognitive processes. A representative model thus needs to account for the ways in which iconic recognition differs from ordinary visual recognition. In the second model, which build off of symbolic approaches like that of Nelson Goodman, iconic representation works the same way as other types of symbols, particularly linguistic ones. Thus, this approach considers the similarities between images and language (representations which are both affected by processes of denotation and predication). However, we all know how strongly image theoreticians have been resisting the linguistic paradigm (iconic turn topic): some worry about overlooking the image’s semantic density in favor of its « simple » descriptive quality. Lopes finds a path between these two models by developing a « theory of aspect recognition », which incorporates perceptive elements into a symbolic structure. According to Lopes, if we agree that images belong to symbolic systems of denotation, then « they might be symbols for which the reference is dependent on the carrying out of perceptive aptitudes », a claim which my talk will explore. I will also discuss how Lopes’ theory accounts for skills acquisition (the capacity to recognize) through images, and shows how images help these skills progressively develop. [less ▲]

Detailed reference viewed: 18 (0 ULg)
Full Text
Peer Reviewed
See detailAsynchronous Power Flow on Graphic Processing Units
Marin, Manuel ULg; Defour, David; Milano, Federico

in Procedings (2017)

Detailed reference viewed: 20 (1 ULg)
Full Text
Peer Reviewed
See detailA French version of the Balanced Time Perspective Scale: Factor structure and relation to cognitive reappraisal.
Barsics, Catherine ULg; Rebetez, Marie; Rochat, Lucien et al

in Canadian Journal of Behavioural Science = Revue Canadienne des Sciences du Comportement (2017), 49(1), 51-57

A frequent and equal tendency to think positively about one’s past and future has been conceptualised as a balanced time perspective (TP). Such a dispositional temporal orientation has been associated ... [more ▼]

A frequent and equal tendency to think positively about one’s past and future has been conceptualised as a balanced time perspective (TP). Such a dispositional temporal orientation has been associated with higher life satisfaction and happiness. The aim of the present study was to develop and to validate a French version of the Balanced Time Perspective Scale (BTPS; Webster, 2011), which has been specifically designed to assess the combined use of positive future and past mental representations as resources for the self. Data were collected from an online survey in a sample of 622 French-speaking individuals from the general population. Results indicated that the French version of the BTPS replicated the 2-factor structure of the original questionnaire, and showed excellent internal consistency. External validity was supported by specific rela- tionships with measures of TP and positive affect. In addition, a high propensity to project oneself positively both in the future and the past was associated with greater use of cognitive reappraisal. [less ▲]

Detailed reference viewed: 30 (0 ULg)
Full Text
Peer Reviewed
See detailDesign sensitivity analysis for shape optimization based on the Lie derivative
Kuci, Erin ULg; Henrotte, François ULg; Duysinx, Pierre ULg et al

in Computer Methods in Applied Mechanics & Engineering (2017)

Abstract The paper presents a theoretical framework for the shape sensitivity analysis of systems governed by partial differential equations. The proposed approach, based on geometrical concepts borrowed ... [more ▼]

Abstract The paper presents a theoretical framework for the shape sensitivity analysis of systems governed by partial differential equations. The proposed approach, based on geometrical concepts borrowed from differential geometry, shows that sensitivity of a performance function (i.e. any function of the solution of the problem) with respect to a given design variable can be represented mathematically as a Lie derivative, i.e. the derivative of that performance function along a flow representing the continuous shape modification of the geometrical model induced by the variation of the considered design variable. Theoretical formulae to express sensitivity analytically are demonstrated in detail in the paper, and applied to a nonlinear magnetostatic and a linear elastic problem, following both the direct and the adjoint approaches. Following the analytical approach, one linear system of which only the right-hand side needs be evaluated (the system matrix being known already) has to be solved for each of the design variables in the direct approach, or for each performance functions in the adjoint approach. A substantial gain in computation time is obtained this way compared to a finite difference evaluation of sensitivity, which requires solving a second nonlinear system for each design variable. This is the main motivation of the analytical approach. There is some freedom in the definition of the auxiliary flow that represents the shape modification. We present a method that makes benefit of this freedom to express sensitivity locally as a volume integral over a single layer of finite elements connected to both sides of the surfaces undergoing shape modification. All sensitivity calculations are checked with a finite difference in order to validate the analytic approach. Convergence is analyzed in 2D and 3D, with first and second order finite elements. [less ▲]

Detailed reference viewed: 40 (8 ULg)
Full Text
See detailPortrait et durabilité de différentes voies de valorisations des ressources céréalières wallonnes. Résultats extraits du projet ALT-4-CER
Van Stappen, Florence; Delcour, Alice ULg; Decruyenaere, Virginie et al

in Bodson, Bernard; Watillon, Bernard (Eds.) Livre Blanc Céréales : 1967-2017 : 50 ans de partenariat entre agriculteurs et chercheurs. Edition février 2017 (2017)

Cet article a pour but de communiquer de manière succincte les résultats du projet ALT-4-CER, financé par le Centre wallon de Recherches agronomiques (CRA-W) sur base des fonds de la loi de ... [more ▼]

Cet article a pour but de communiquer de manière succincte les résultats du projet ALT-4-CER, financé par le Centre wallon de Recherches agronomiques (CRA-W) sur base des fonds de la loi de défiscalisation des institutions de recherches Moerman. Ce projet s'est déroulé de mars 2011 à juillet 2015. Le projet comportait les objectifs suivants : (1) dresser un portrait des utilisations actuelles des céréales wallonnes ; (2) élaborer des scénarios originaux d'évaluations possibles de l'utilisation des céréales wallonnes en concertation avec le secteur wallon ; (3) évaluer, sur base d'analyses du cycle de vie (ACV), les impacts environnementaux (et socio-économiques, disponibles mais non repris dans cet article) de la production et la transformation des céréales wallonnes selon des exemples de filières de valorisation. L'article présente des informations, extraites des résultats du projet, sur le portrait en 2010 de la valorisation des céréales wallonnes et sur l'estimation de l'impact environnemental de la production de céréales en Wallonie. Il se limite à donner les conclusions et messages-clés de l'étude sur la construction de scénarios possibles d'évolution de l'utilisation des céréales wallonnes d'une part et, d'autre part, sur l'utilisation des céréales pour la production d'énergie. [less ▲]

Detailed reference viewed: 15 (1 ULg)
Full Text
Peer Reviewed
See detailLe commun à l'épreuve du conflit : médiation esthétique et expérience de la communauté
Servais, Christine ULg

in Recherches en Communication (2017)

Cet article propose une conception de la médiation culturelle où la notion de médiation est lestée d’un rapport complexe au tiers, rapport susceptible de prendre en compte le conflit que peut constituer ... [more ▼]

Cet article propose une conception de la médiation culturelle où la notion de médiation est lestée d’un rapport complexe au tiers, rapport susceptible de prendre en compte le conflit que peut constituer la prise de position du destinataire auquel s’adressent les dispositifs de médiation. Cette approche de la médiation conserve la distinction entre passage et forçage, ce qui la situe dans un cadre politique. [less ▲]

Detailed reference viewed: 45 (9 ULg)
Full Text
Peer Reviewed
See detailSpaces Snu, diametral dimension and property Omega bar
Demeulenaere, Loïc ULg

in Journal of Mathematical Analysis and Applications (2017), 449(2), 1340-1350

This paper investigates two topological invariants in the context of the sequence spaces Snu, which are metric topological vector spaces defined in order to study the regularity of signals. First, it ... [more ▼]

This paper investigates two topological invariants in the context of the sequence spaces Snu, which are metric topological vector spaces defined in order to study the regularity of signals. First, it extends the formula already known of the diametral dimension of spaces Snu to some non-locally pseudoconvex ones. Second, it proves that locally p-convex spaces Snu verifies the property "Omega id", which is equivalent to Omega bar for Fréchet spaces. [less ▲]

Detailed reference viewed: 48 (34 ULg)
Full Text
Peer Reviewed
See detailFederalism and decentralisation in Belgium
Husson, Jean-François ULg; Mahieu, Céline; Sägesser, Caroline

in Ruano de la Fuente, José-Manuel (Ed.) The Palgrave Handbook on Decentralisation in Europe (2017)

This chapter explain the Belgian federalism (Regions, Communities) and decentralisation (provinces, municipalities,...). Competencies, coordination bodies and financing schemes are described while ... [more ▼]

This chapter explain the Belgian federalism (Regions, Communities) and decentralisation (provinces, municipalities,...). Competencies, coordination bodies and financing schemes are described while presenting some challenges ahead. [less ▲]

Detailed reference viewed: 51 (7 ULg)
Full Text
Peer Reviewed
See detailOn the equality between two diametral dimensions
Bastin, Françoise ULg; Demeulenaere, Loïc ULg

in Functiones et Approximatio Commentarii Mathematici (2017), 56(1), 95-107

Detailed reference viewed: 117 (60 ULg)