Browsing
     by title


0-9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

or enter first few letters:   
OK
Full Text
Peer Reviewed
See detailThe contribution of large genomic deletions at the CDKN2A locus to the burden of familial melanoma.
Lesueur, F.; de Lichy, M.; Barrois, M. et al

in British Journal of Cancer (2008), 99(2), 364-70

Mutations in two genes encoding cell cycle regulatory proteins have been shown to cause familial cutaneous malignant melanoma (CMM). About 20% of melanoma-prone families bear a point mutation in the ... [more ▼]

Mutations in two genes encoding cell cycle regulatory proteins have been shown to cause familial cutaneous malignant melanoma (CMM). About 20% of melanoma-prone families bear a point mutation in the CDKN2A locus at 9p21, which encodes two unrelated proteins, p16(INK4a) and p14(ARF). Rare mutations in CDK4 have also been linked to the disease. Although the CDKN2A gene has been shown to be the major melanoma predisposing gene, there remains a significant proportion of melanoma kindreds linked to 9p21 in which germline mutations of CDKN2A have not been identified through direct exon sequencing. The purpose of this study was to assess the contribution of large rearrangements in CDKN2A to the disease in melanoma-prone families using multiplex ligation-dependent probe amplification. We examined 214 patients from independent pedigrees with at least two CMM cases. All had been tested for CDKN2A and CDK4 point mutation, and 47 were found positive. Among the remaining 167 negative patients, one carried a novel genomic deletion of CDKN2A exon 2. Overall, genomic deletions represented 2.1% of total mutations in this series (1 of 48), confirming that they explain a very small proportion of CMM susceptibility. In addition, we excluded a new gene on 9p21, KLHL9, as being a major CMM gene. [less ▲]

Detailed reference viewed: 80 (22 ULg)
Full Text
Peer Reviewed
See detailContribution of Lexico-Semantic Processes to Verbal Short-Term Memory Tasks: A Pet Activation Study
Collette, Fabienne ULg; Majerus, Steve ULg; Van der Linden, Martial ULg et al

in Memory (2001), 9(4-6), 249-259

Recent studies have demonstrated the intervention of long-term memory processes in verbal STM tasks and several cognitive models have been proposed to explain these effects. A PET study was performed in ... [more ▼]

Recent studies have demonstrated the intervention of long-term memory processes in verbal STM tasks and several cognitive models have been proposed to explain these effects. A PET study was performed in order to determine whether supplementary cerebral areas are involved when subjects have to execute short-term memory tasks for items having representations in long-term memory (in comparison to items without such representations: words vs non-words). Results indicate that verbal STM for words specifically involves the left middle temporal gyrus (BA 21) and temporo-parietal junction (BA 39). These areas can be associated with lexical and semantic processes. These results are in agreement with cognitive models that postulate the simultaneous influence of lexical and semantic long-term representations on verbal STM processes and/or a lexico-semantic buffer. [less ▲]

Detailed reference viewed: 42 (4 ULg)
Full Text
See detailThe contribution of macroalgae to the assessment of the ecological quality of the rivers in Wallonia based on macrophytes indicator values in the British and French approaches.
Sossey Alaoui, Khadija ULg; Galoux, Daniel; Rosillon, Françis ULg

Poster (2009)

In accordance with the water Framework Directive (WFD, European Parliament & The Council of the European Union, 2000) defining the overall ecological status of rivers, many hundred sites were analysed in ... [more ▼]

In accordance with the water Framework Directive (WFD, European Parliament & The Council of the European Union, 2000) defining the overall ecological status of rivers, many hundred sites were analysed in the Walloon network. Within each sample, macroalgae data were gathered at species/or at genus level and the main water quality parameters were collected several times per year from 2005 to 2009. <br /><br />Seventeen species and genera cited in the French and English lists of macrophyte methods used to assess the ecological quality of rivers were considered. Within these sites, the ratio of the macroalgae among the contributory species was examined and the impact of these on the final scores of the River Macrophytes Nutrient index (United Kingdom, Wilby et al.,2006) and the biological macrophytic index in rivers (France, Haury et al., 2006) was analysed.At the same time, a ranking of these macroalgae along a trophy gradient has been established thanks to a principal component analysis of the physico-chemical parameters and a weighting of the species presence in a given waterbody by its abundance.The relationships between macroalgae scores and those found in France and in United Kingdom were studied using the Spearman rank correlation coefficient. <br /><br />Literature: <br /><br />European Parliament & The Council of the European Union, 2000. Directive 2000/60/EC of the European Parliament and of the Council establishing a framework for the Community action in the field of water policy. Official Journal of the European Communities 327: 1-72.Haury, J., M.-C. Peltre, M. Trémolières, J. Barbe, G. Thiébaut, I. Bernez, H. Daniel, P. Chatenet, G. Haan-Archipof, S. Muller, A. Dutartre, C. Laplace-Treyture, A. Cazaubon & E. Lambert-Servien, 2006. A new method to assess water trophy and organic pollution – the Macrophyte Biological Index for Rivers (IBMR): its application to different types of river and pollution. Hydrobiologia 570: 153-158. Willby, N., J. Pitt & G. Phillips, 2006. Summary of approach used in LEAFPACS for defining ecological quality of rivers and lakes using macrophyte composition. Draft Report January 2006. [less ▲]

Detailed reference viewed: 96 (9 ULg)
Full Text
Peer Reviewed
See detailContribution of MT1-MMP and of Human Laminin-5 Gamma2 Chain Degradation to Mammary Epithelial Cell Migration
Gilles, Christine ULg; Polette, M.; Coraux, C. et al

in Journal of Cell Science (2001), 114(Pt 16), 2967-76

Membrane-type matrix metalloproteinase 1 (MT1-MMP) is a membrane-anchored matrix metalloproteinase (MMP) that is frequently associated with processes involving tissue remodelling and cell migration. We ... [more ▼]

Membrane-type matrix metalloproteinase 1 (MT1-MMP) is a membrane-anchored matrix metalloproteinase (MMP) that is frequently associated with processes involving tissue remodelling and cell migration. We have examined MT1-MMP expression and subcellular distribution as a function of MCF10A mammary epithelial cell migration using an in vitro outgrowth migration assay. Stronger expression of MT1-MMP was observed at the mRNA and at the protein level in cells at the periphery of the outgrowth. As shown by videomicroscopy, these cells were involved in an orientated cell migration, in contrast to stationary cells distant from the periphery. Furthermore, MT1-MMP was mainly distributed in lamellipodia of migratory cells, as well as at their basal surface in contact with the substrate. Laminin-5 (Ln-5), a recently described substrate for MT1-MMP, was deposited preferentially in the matrix by migratory cells. Fragments of the gamma2 subunit of Ln-5 were also identified in migratory cultures of MCF10A cells, attesting to its proteolytic degradation. These fragments corresponded in size to those we observed after incubation of purified human Ln-5 with the recombinant catalytic domain of human MT1-MMP. We also show that anti-Ln5 blocking antibodies, MMP inhibitors (BB94 and TIMP-2) and MT1-MMP antisense oligonucleotides significantly decreased MCF10A cell migration. Taken together, these observations demonstrate that MT1-MMP is spatially and temporally regulated during MCF10A cell migration, and suggest that MT1-MMP-mediated pericellular proteolysis of Ln-5 gamma2 chain could contribute to this process. [less ▲]

Detailed reference viewed: 58 (4 ULg)
Full Text
Peer Reviewed
See detailThe contribution of multi-purpose farming to the food security of small-scale farmers: An agro-economic analysis in the lowland Mekong alluvial plain
Tong, Chantheang; Diepart, Jean-Christophe ULg

in Diepart, Jean-Christophe (Ed.) Learning for resilience: Insights from Cambodia’s rural communities (2015)

Agricultural development models are the focus of intense debate in the Cambodian policy-making arenas. A model inspired by the ‘Green Revolution’, which promotes industrialization of rice cropping systems ... [more ▼]

Agricultural development models are the focus of intense debate in the Cambodian policy-making arenas. A model inspired by the ‘Green Revolution’, which promotes industrialization of rice cropping systems and is mainly dependent on external inputs, is usually contrasted with multi-purpose farming (MPF) in which rice cropping is integrated with other production to maximize their interactions and complementarities. The purpose of this research is to present some economic arguments based on the experience in promoting MPF of CEDAC (Centre d’Etude et de Dévelopement Agricole Cambodgien, also known as the Cambodian Center for Study and Development in Agriculture). We develop a comparative analysis between conventional rice cropping systems and MPF to analyze the production economics and the overall patterns of household labor diversification. Focusing primarily on rainy-season rice production, we attribute significant advantage to MPF against non-MPF practices. These differences are perceptible in higher rice yield, lower cash-paid costs, and higher value-added per hectare. However, these differences become less significant when multi-purpose farming is only partially implemented, i.e. if some elements of the system are missing. MPF provides employment opportunities that represent a reliable alternative to job migration. Under MPF, family labor is used more on-farm than is the case with non- MPF farms and is more homogenously distributed throughout the year. However, we identify barriers that curb the scaling-up of this innovation, which include limited access to information, anticipated lack of labor, lack of capacity or technical skills, lack of up-front capital to make the initial investment in land conversion to MPF, and land plot sizes that are too small to be converted to this model. We also discuss the opportunities to create markets for products of differentiated quality produced under multi-purpose farming. [less ▲]

Detailed reference viewed: 13 (0 ULg)
Peer Reviewed
See detailThe contribution of Multidimensional IRT for modeling applicants performance on a SJT.
Lothe, Benoit ULg; Monseur, Christian ULg; Hansez, Isabelle ULg

Poster (2013, May)

Situational judgment tests (SJTs) are testing methods often used in Personnel Selection to appraise different constructs (Whetzel & McDaniel, 2009). In the framework of an overall career progression ... [more ▼]

Situational judgment tests (SJTs) are testing methods often used in Personnel Selection to appraise different constructs (Whetzel & McDaniel, 2009). In the framework of an overall career progression program in a Public Administration, SJTs were developed to assess several competencies relevant to both task (e.g. planning, managing, etc.) and contextual performance (e.g. helping behaviour, organizational loyalty, etc.). Each competency is a combination of KSAOs needed to perform efficiently in a specific context (Campion & al., 2012; Le Boterf 2008). Given the lack of internal consistency of SJT and the dichotomous nature of the data, we decide to use Multidimensional Item Response Theory (MIRT) model to examine the issue of construct validity. Based on Hartig & Höhler (2009), we use MIRT compensatory model to estimate the latent covariance structures of the SJT. Different model are tested and compared depending on the number of dimension involved, the nature of the items and latent variables relation (between or within-item multidimensionality) and the number of model parameter (one or two parameter model). The results and findings lead us to discuss some implications (gaining accuracy, modeling performance in complex task, etc.) and limitations (dealing with complex loading structure, etc.) of using IRT, over and above classical test theory, in the specific case of SJTs applicants performance. The originality of this communication also lies in the way we addressed SJTs reliability and construct validity issues with a measurement based model that differs from the one usually used in the field. [less ▲]

Detailed reference viewed: 115 (7 ULg)
Full Text
Peer Reviewed
See detailContribution of Mutant Analysis to the Understanding of Enzyme Catalysis: The Case of Class a Beta-Lactamases
Matagne, André ULg; Frère, Jean-Marie ULg

in Biochimica et Biophysica Acta (1995), 1246(2), 109-27

Class A beta-lactamases represent a family of well studied enzymes. They are responsible for many antibiotic resistance phenomena and thus for numerous failures in clinical chemotherapy. Despite the facts ... [more ▼]

Class A beta-lactamases represent a family of well studied enzymes. They are responsible for many antibiotic resistance phenomena and thus for numerous failures in clinical chemotherapy. Despite the facts that five structures are known at high resolution and that detailed analyses of enzymes modified by site-directed mutagenesis have been performed, their exact catalytic mechanism remains controversial. This review attempts to summarize and to discuss the many available data. [less ▲]

Detailed reference viewed: 73 (3 ULg)
Peer Reviewed
See detailContribution of MX dynamin, oligoadenylate synthetase, and protein kinase R to anti-paramyxovirus activity of type-1 interferons in vitro
Leroy, M.; Baise, Etienne ULg; Pire, G. et al

in American Journal of Veterinary Research (2007), 68

OBJECTIVE: To determine the contribution of MX dynamin, oligoadenylate synthetase (OAS), and double-stranded RNA-dependent protein kinase R (PKR) to the antiviral effects of type 1 interferons (IFNs ... [more ▼]

OBJECTIVE: To determine the contribution of MX dynamin, oligoadenylate synthetase (OAS), and double-stranded RNA-dependent protein kinase R (PKR) to the antiviral effects of type 1 interferons (IFNs) against bovine parainfluenza-3 virus (PI-3V) infection of Vero cells. SAMPLE POPULATION: Vero cell cultures. PROCEDURES: PI-3V yield was first compared between control and transfected type 1 IFNs-incompetent Vero cells expressing recombinant OAS or MX proteins. Afterwards, phosphorylation of eukaryotic initiation factor 2 alpha (eIF2alpha) was used to scale the degree of PKR activation upon infection of Vero cells by PI-3V. RESULTS: Overexpression of OAS did not result in significantly decreased viral replication. Phosphorylated eIF2alpha forms, the hallmark of PKR activation, were not increased in IFNalpha-primed infected Vero cells. Although human MXA contributed to partial blockade of replication of bovine PI-3V, the antiviral effect was not as strong as that of IFNalpha. CONCLUSIONS AND CLINICAL RELEVANCE: The powerful anti-Paramyxovirus activity of type 1 IFNs is mediated by noncanonic pathways. [less ▲]

Detailed reference viewed: 46 (1 ULg)
Full Text
Peer Reviewed
See detailContribution of nanoclays to the barrier properties of a model proton exchange membrane for fuel cell application
Thomassin, Jean-Michel ULg; Pagnoulle, Christophe; Caldarella, Giuseppe ULg et al

in Journal of Membrane Science (2006), 270(1-2), 50-56

Direct methanol fuel cells (DMFCs) that use a proton exchange membrane (PEM) as electrolyte, is a promising alternative source of energy for the future. However, methanol crossover from the anodic side to ... [more ▼]

Direct methanol fuel cells (DMFCs) that use a proton exchange membrane (PEM) as electrolyte, is a promising alternative source of energy for the future. However, methanol crossover from the anodic side to the cathodic one is a major problem in DMFC. Proper dispersion of layered silicates within the fuel cell membrane has been proposed as a strategy for improving the barrier properties of the membrane. The validity of this approach has been tested in case of a model membrane consisting of phosphotungstic acid doped poly(vinyl alcohol). A solvent casting technique has been used, which allows the nanofiller to be delaminated by an ultrasonic pre-treatment, as confirmed by TEM and XRD analysis. The layered silicates have a favourable impact on the methanol permeability, whose the decrease overcompensates some loss in ionic conductivity. [less ▲]

Detailed reference viewed: 38 (0 ULg)
Full Text
See detailContribution of new radiocarbon dates to track the impact of past anthropogenic disturbances on current vegetation in Central Africa
Morin-Rivat, Julie ULg; Gillet, Jean-François ULg; Bourland, Nils ULg et al

Poster (2012, July)

Introduction: Understanding current Central Africa vegetation patterns faces the scarcity of data about their past evolution. However, a growing hypothesis suggests that past human activities could have ... [more ▼]

Introduction: Understanding current Central Africa vegetation patterns faces the scarcity of data about their past evolution. However, a growing hypothesis suggests that past human activities could have had a substantial influence on vegetation (Van Gemerden et al. 2003, Brncic et al. 2009). Indeed, by creating large openings (fig. 1), they might have triggered the expansion of light-demanding species currently suffering from a lack of regeneration. This lack of saplings could have been caused by the change in land use since colonization with the sedentarization of shifting cultivators. Aim of the study: To investigate the potential relationship between past anthropogenic disturbances and present vegetation. Material & methods: Fieldworks combining anthracological and ecological approaches have been undertaken in Northern Congo and South-Eastern Cameroon (fig. 2). We excavated thirty 150-200 cm deep pits under different forest covers and vegetation types to identify evidences of past human presence (i.e potsherds, fig. 3, slags from metallurgy, anthropogenic pieces of charcoals and anthropophilous charred seeds). Charcoals and seeds (oil palm Elaeis guineensis, fig. 4, Canarium schweinfurthii) in combination with artifacts have been dated. Results: A set of 38 new radiocarbon dates ranging from 15,200 cal BP to present time have been obtained. They confirm the existence of important past fire events in a region where natural ones seldom occur. Together with artifacts, our findings support the few already available dates documenting evidences of past human activities in Central African rainforests. On the 36 most recent dates (fig. 5), the majority belongs to the 2,300-1,400 cal BP period (61%). The whole semi-deciduous forest zone is concerned by this period of intense disturbances with a high rate of fragmentation. It follows the last great arid phase ca. 2,500 cal BP and might be linked to the iron workers expansion. Another pool of dates between 650 and 250 cal BP (33%) associated with potsherds might be correlated to a dry phase contemporary to the Little Ice Age in Europe. That last group of dates points out the potential positive impact of anthropogenic disturbances connected to a dry climatic event on light-demanding species populations. Indeed, this is consistent with the fact that most of current light-demanding trees have a higher number of stems around 100 cm dbh. Conclusion: Our multidisciplinary approach allowed new insights into the link between human history and vegetation dynamics in Central Africa. Further investigations should be conducted to go deeper into the understanding of the evolution of Central African rainforests and to improve the management of currently logged light-demanding species resulting from the LIA period. Thirty new dates from sixteen soil profiles are forthcoming. References: Brncic T., Willis M., K. J., Harris D. J., Telfer M. W. & Bailey M. W. 2009. Fire and climate change impacts on lowland forest composition in northern Congo during the last 2580 years from palaeoecological analyses of a seasonally flooded swamp. The Holocene, 19, 79-89. Reimer P. J., Baillie M. G. L., Bard E., Bayliss A., Beck J. W., Blackwell P. G., Bronk Ramsey C., Buck C. E., Burr G. S., Edwards R. L., Friedrich M., Grootes P. M., Guilderson T. P., Hajdas I., Heaton T. J., Hogg A. G., Hughen K. A., Kaiser K. F., Kromer B., McCormac F. G., Manning S. W., Reimer R. W., Richards D. A., Southon J.R., Talamo S., Turney C. S. M., van der Plicht J., & Weyhenmeyer, C. E. 2009. IntCal09 and Marine09 radiocarbon age calibration curves, 0-50,000 years cal BP. Radiocarbon, 51(4), 1111-1150. Van Gemerden B. S., Olff H., Parren M. P. E, Bongers F. 2003. The pristine rain forest? Remnants of historical human impacts on current tree species composition and diversity. Journal of Biogeography, 30, 1381-1390. [less ▲]

Detailed reference viewed: 389 (57 ULg)
Full Text
Peer Reviewed
See detailCONTRIBUTION OF NEW TECHNIQUES TO STUDY GAIT IN THE OLDERS
GILLAIN, Sophie ULg; Petermans, Jean ULg

in Annals of Physical and Rehabilitation Medicine (2013), 56

Detailed reference viewed: 42 (4 ULg)
Peer Reviewed
See detailContribution of Peripheral Blood Pooling to Central Hemodynamic Disturbances During Endotoxin Insult in Intact Dogs
D'Orio, Vincenzo ULg; Wahlen, C.; Naldi, Marco ULg et al

in Critical Care Medicine (1989), 17(12), 1314-9

The aim of the present study was to determine possible effects of Escherichia coli endotoxin on peripheral vascular compliance and relate them to concomitant central hemodynamic disturbances. Endotoxin ... [more ▼]

The aim of the present study was to determine possible effects of Escherichia coli endotoxin on peripheral vascular compliance and relate them to concomitant central hemodynamic disturbances. Endotoxin was infused at 0.25 micrograms/kg.min during 2 h in six anesthetized dogs, while six additional animals served as controls. Vascular compliance of the systemic circulation was calculated in intact animals from the changes in CVP after known changes in systemic blood volume. In control dogs, vascular compliance averaged 2.3 ml/mm Hg.kg body weight. During slow endotoxin infusion, cardiovascular effects were measurable only after a certain period of time had elapsed from the start of endotoxin insult and consisted of hypotension associated with systemic vasodilation. Systemic BP decreased gradually from 124 to 68 mm Hg while vascular compliance was finally increased by 100%, when compared to control values. This latter rise was responsible for a reduction in the cardiac preloads. Pulmonary wedge pressure and CVP were decreased from 7.1 to 3.4 and from 4.5 to 2.6 mm Hg, respectively. However, parallel to the decrease in left ventricular preload, endotoxin induced a progressive decrease in left ventricular afterload. Because of the balance in ventricular loading, cardiac output remained almost unchanged. After volume loading (dextran 30 ml/kg), cardiac output was remarkably increased from 3.28 to 6.24 L/min.m2 while peripheral vasodilation was not affected by this maneuver. It is concluded that low dose endotoxin infusion induces in dogs a hemodynamic pattern similar to human sepsis. The left ventricular loading changes are related to an enhanced systemic vascular compliance from 2.3 to 4.5 ml/mm Hg.kg. High flow shock state is encountered provided peripheral blood pooling is compensated by adequate volume replacement. [less ▲]

Detailed reference viewed: 53 (2 ULg)
Full Text
Peer Reviewed
See detailContribution of Pet Scanning to the Evaluation of Abdominal Aortic Aneurysm
Sakalihasan, Natzi ULg; Hustinx, Roland ULg; Limet, Raymond ULg

in Seminars in Vascular Surgery (2004), 17(2), 144-53

The size of abdominal aortic aneurysms (AAA) is the most usual predictor of the risk for rupture. Because chronic metalloproteinases production and activation by inflammatory cells causes degradation of ... [more ▼]

The size of abdominal aortic aneurysms (AAA) is the most usual predictor of the risk for rupture. Because chronic metalloproteinases production and activation by inflammatory cells causes degradation of elastin and collagen in the aneurysmal wall, the detection of an increased metabolic process preceding fissuration and rupture could be a more sensitive predictor of rupture risk. We investigated the metabolic activity of the aneurysmal wall by whole-body positron emission tomography (PET) in 26 patients with a documented AAA (mean diameter 63 mm, extremes 45 mm and 78 mm). A positive (18)F-fluorodeoxyglucose ((18)F-FDG) uptake at the level of the AAA was observed in 38% of the cases (10 of 26 patients). Nine of these 10 patients required emergent or urgent aneurysmectomy for ruptured (n = 1), leaking (n = 1), rapidly expanding (n = 2), or painful (n = 5) aneurysms; the negative (18)F-FDG uptake patients had a more benign course. This preliminary study suggests a possible correlation between (18)F-FDG uptake by the aneurysm wall and the triggering of processes leading to rupture. The (18)F-FDG uptake in the aneurysm wall may correspond to the accumulation of inflammatory cells responsible for the production and activation of degrading enzymes. PET scan seems useful in high-risk patients. Positive PET imaging in these cases would help us to decide to proceed with surgery, despite factors favoring a surveillance strategy. [less ▲]

Detailed reference viewed: 64 (8 ULg)
Full Text
Peer Reviewed
See detailContribution of platelet glycoprotein VI to the thrombogenic effect of collagens in fibrous atherosclerotic lesions.
Cosemans, Judith M E M; Kuijpers, Marijke J E; Lecut, Christelle ULg et al

in Atherosclerosis (2005), 181(1), 19-27

Collagens (types I and III) are among the strongest thrombus-forming components of the vascular subendothelium. We compared the thrombogenic effects of four collagen-containing advanced atherosclerotic ... [more ▼]

Collagens (types I and III) are among the strongest thrombus-forming components of the vascular subendothelium. We compared the thrombogenic effects of four collagen-containing advanced atherosclerotic lesions with those of purified types I and III collagen fibers. Cell-free homogenates from the human plaques effectively promoted platelet adhesion and aggregate formation under high-shear flow conditions, as well as exposure of procoagulant phosphatidylserine (PS) on platelets. With all plaques, blocking of the glycoprotein VI (GPVI) receptor for collagen abolished aggregation and PS exposure. Blocking of platelet ADP receptors resulted in similar, but less complete inhibitory effects. Type I collagen was more potent than type III collagen in inducing aggregation and PS exposure under flow, via stimulation of GPVI and ADP receptors. Type I collagen also more strongly enhanced thrombin generation with platelets and tissue factor, again via GPVI activation and PS exposure. The plaque material enhanced thrombin generation, partly due to the presence of tissue factor and partly via GPVI and ADP receptors. Together, these results indicate that in advanced plaques collagen type I is a major trigger of thrombus formation and PS exposure, acting via GPVI and ADP release, while tissue factor directly enhances coagulation. [less ▲]

Detailed reference viewed: 41 (4 ULg)
Full Text
Peer Reviewed
See detailContribution of polyalky(meth)acrylates to the design of PVC melt viscosity
Vankan, R.; Fayt, Roger; Jérôme, Robert ULg et al

in Polymer Engineering & Science (1996), 36(12), 1675-1684

The shear viscosity of poly(vinylchloride) (PVC) at 200°C can be decreased by at least one order of magnitude by the addition of as little as 5 wt% poly n-alkyl-(meth)acrylates (PMA) of a much lower ... [more ▼]

The shear viscosity of poly(vinylchloride) (PVC) at 200°C can be decreased by at least one order of magnitude by the addition of as little as 5 wt% poly n-alkyl-(meth)acrylates (PMA) of a much lower dynamic viscosity than PVC. For this effect to be observed, the polymeric additive must be immiscible with PVC at 200°C. The average size of the dispersed phases is observed in the range of 0.5 to 5 m; size fluctuation in this domain has no significant effect. When these conditions are met, there is a linear increase in the shear viscosity ratio blend/PVC from 0.2 to 1.0 with increasing logarithmic values of the dynamic viscosity ratio of the additive over PVC [(log(/)) from -4 to -1]. [less ▲]

Detailed reference viewed: 18 (4 ULg)
Full Text
Peer Reviewed
See detailContribution of positron emission tomography in pleural disease.
Duysinx, Bernard ULg; Corhay, Jean-Louis ULg; Larock, Marie-Paule ULg et al

in Revue des Maladies Respiratoires (2010), 27(8), 47-53

INTRODUCTION: Positron emission tomography (PET) now plays a clear role in oncology, especially in chest tumours. We discuss the value of metabolic imaging in characterising pleural pathology in the light ... [more ▼]

INTRODUCTION: Positron emission tomography (PET) now plays a clear role in oncology, especially in chest tumours. We discuss the value of metabolic imaging in characterising pleural pathology in the light of our own experience and review the literature. BACKGROUND: PET is particularly useful in characterising malignant pleural pathologies and is a factor of prognosis in mesothelioma. Metabolic imaging also provides clinical information for staging lung cancer, in researching the primary tumour in metastatic pleurisy and in monitoring chronic or recurrent pleural pathologies. CONCLUSIONS: PET should therefore be considered as a useful tool in the diagnosis of liquid or solid pleural pathologies. [less ▲]

Detailed reference viewed: 58 (5 ULg)