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See detailThe Human Vpac(1) Receptor - Three-Dimensional Model And Mutagenesis Of The N-Terminal Domain
Lins, Laurence ULg; Couvineau, A.; Rouyer-Fessard, C. et al

in Journal of Biological Chemistry (2001), 276(13),

The human VPAC(1) receptor for vasoactive intestinal peptide (VIP) and pituitary adenylate cyclase activating peptide belongs to the class II family of G-protein-coupled receptors with seven transmembrane ... [more ▼]

The human VPAC(1) receptor for vasoactive intestinal peptide (VIP) and pituitary adenylate cyclase activating peptide belongs to the class II family of G-protein-coupled receptors with seven transmembrane segments. Like for all class II receptors, the extracellular N-terminal domain of the human VPAC(1) receptor plays a predominant role in peptide ligand recognition. To determine the three-dimensional structure of this N-terminal domain (residues 1-144), the Protein Data Bank (PDB) was screened for a homologous protein. A subdomain of yeast lipase B was found to have 27% sequence identity and 50% sequence homology with the N-terminal domain (8) of the VPAC(1) receptor together with a good alignment of the hydrophobic clusters. A model of the N-terminal domain of VPAC(1) receptor was thus constructed by homology. It indicated the presence of a putative signal sequence in the N-terminal extremity. Moreover, residues (Glu(36), Trp(67), Asp(68), Trp(73), and Gly(109)) which were shown to be crucial for VIP binding are gathered around a groove that is essentially negatively charged. New putatively important residues for VIP binding were suggested from the model analysis. Site-directed mutagenesis and stable transfection of mutants in CHO cells indicated that Pro(74), Pro(87), Phe(90), and Trp(110) are indeed important for VIP binding and activation of adenylyl cyclase activation. Combination of molecular modeling and directed mutagenesis provided the first partial three-dimensional structure of a VIP-binding domain, constituted of an electronegative groove with an outspanning tryptophan shell at one end, in the N-terminal extracellular region of the human VPAC(1) receptor. [less ▲]

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See detailExpression and function of the collagen receptor GPVI during megakaryocyte maturation.
Lagrue-Lak-Hal, A. H.; Debili, N.; Kingbury, G. et al

in Journal of Biological Chemistry (2001), 276(18), 15316-25

In this report, the expression and function of the platelet collagen receptor glycoprotein VI (GPVI) were studied in human megakaryocytes during differentiation and maturation of mobilized blood and cord ... [more ▼]

In this report, the expression and function of the platelet collagen receptor glycoprotein VI (GPVI) were studied in human megakaryocytes during differentiation and maturation of mobilized blood and cord blood derived CD34(+) cells. By flow cytometry, using an anti-GPVI monoclonal antibody or convulxin, a GPVI-specific ligand, GPVI was detected only on CD41(+) cells including some CD41(+)/CD34(+) cells, suggesting expression at a stage of differentiation similar to CD41. These results were confirmed at the mRNA level using reverse transcription-polymerase chain reaction. GPVI expression was low during megakaryocytic differentiation but increased in the more mature megakaryocytes (CD41(high)). As in platelets, megakaryocyte GPVI associates with the Fc receptor gamma chain (FcRgamma). The FcR gamma chain was detected at the RNA and protein level at all stages of megakaryocyte maturation preceding the expression of GPVI. The other collagen receptor, alpha(2)beta(1) integrin (CD49b/CD29), had a pattern of expression similar to GPVI. Megakaryocytic GPVI was recognized as a 55-kDa protein by immunoblotting and ligand blotting, and thus it presented a slightly lower apparent molecular mass than platelet GPVI (58 kDa). Megakaryocytes began to adhere to immobilized convulxin via GPVI after only 8-10 days of culture, at a time when megakaryocytes were maturing. At this stage of maturation, they also adhered to immobilized collagen by alpha(2)beta(1) integrin-dependent and -independent mechanisms. Convulxin induced a very similar pattern of protein tyrosine phosphorylation in megakaryocytes and platelets including Syk, FcRgamma, and PLC(gamma)2. Our results showed that GPVI is expressed early during megakaryocytic differentiation but functionally allows megakaryocyte adherence to collagen only at late stages of differentiation when its expression increases. [less ▲]

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See detailPancreas development in zebrafish: early dispersed appearance of endocrine hormone expressing cells and their convergence to form the definitive islet.
Biemar, F.; Argenton, F.; Schmidtke, R. et al

in Developmental Biology (2001), 230(2), 189-203

To begin to understand pancreas development and the control of endocrine lineage formation in zebrafish, we have examined the expression pattern of several genes shown to act in vertebrate pancreatic ... [more ▼]

To begin to understand pancreas development and the control of endocrine lineage formation in zebrafish, we have examined the expression pattern of several genes shown to act in vertebrate pancreatic development: pdx-1, insulin (W. M. Milewski et al., 1998, Endocrinology 139, 1440-1449), glucagon, somatostatin (F. Argenton et al., 1999, Mech. Dev. 87, 217-221), islet-1 (Korzh et al., 1993, Development 118, 417-425), nkx2.2 (Barth and Wilson, 1995, Development 121, 1755-1768), and pax6.2 (Nornes et al., 1998, Mech. Dev. 77, 185-196). To determine the spatial relationship between the exocrine and the endocrine compartments, we have cloned the zebrafish trypsin gene, a digestive enzyme expressed in differentiated pancreatic exocrine cells. We found expression of all these genes in the developing pancreas throughout organogenesis. Endocrine cells first appear in a scattered fashion in two bilateral rows close to the midline during mid-somitogenesis and converge during late-somitogenesis to form a single islet dorsal to the nascent duodenum. We have examined development of the endocrine lineage in a number of previously described zebrafish mutations. Deletion of chordamesoderm in floating head (Xnot homolog) mutants reduces islet formation to small remnants, but does not delete the pancreas, indicating that notochord is involved in proper pancreas development, but not required for differentiation of pancreatic cell fates. In the absence of knypek gene function, which is involved in convergence movements, the bilateral endocrine primordia do not merge. Presence of trunk paraxial mesoderm also appears to be instrumental for convergence since the bilateral endocrine primordia do not merge in spadetail mutants. We discuss our findings on zebrafish pancreatogenesis in the light of evolution of the pancreas in chordates. [less ▲]

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See detailOptimisation des arcs paraboliques et en chaînette – aide à la conception sur base d'indicateurs morphologiques
Latteur, Pierre ULg; Samyn, Philippe; De Wilde, Patrick

in Revue Française de Génie Civil (2001), 5

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See detailLes médias belges et l'"Etat social actif" : genèse, reproduction et diffusion du nouveau sens commun socio-économique
Geuens, Geoffrey ULg

in Quaderni : la Revue de la Communication (2001), 45 ("Figures du journalisme")

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See detailThe organotypic culture of HPV-transformed keratinocytes: an effective in vitro model for the development of new immunotherapeutic approaches for mucosal (pre)neoplastic lesions.
Delvenne, Philippe ULg; Hubert, Pascale ULg; Jacobs, Nathalie ULg et al

in Vaccine (2001), 19(17-19), 2557-64

The purpose of this study is to develop a reliable in vitro human model to test new immunotherapeutic approaches for squamous cell carcinoma that develop on mucosal surfaces. The organotypic (raft ... [more ▼]

The purpose of this study is to develop a reliable in vitro human model to test new immunotherapeutic approaches for squamous cell carcinoma that develop on mucosal surfaces. The organotypic (raft) culture permits cells to proliferate and differentiate at an air-liquid interface on a dermal equivalent support. Normal keratinocytes stratify and fully differentiate in a manner similar to the normal squamous epithelial tissues, while human papillomavirus-immortalized and established squamous carcinoma cell lines exhibit dysplastic morphologies similar to (pre)neoplastic lesions seen in vivo. We have demonstrated the ability of these organotypic cultures to be manipulated by altering the epithelial stratification with cytokines (interferon-gamma and tumor necrosis factor-alpha) and by integrating activated lymphocytes or dendritic cells into the in vitro formed epithelial sheet. This model may provide a useful tool to investigate the factors contributing to the presence and function of immunocompetent cells within a neoplastic epithelium that develops on a mucosal surface. [less ▲]

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See detailEffets benefiques de l'activite physique sur les facteurs de risque cardio-vasculaire.
Scheen, André ULg; Paquot, Nicolas ULg

in Revue Médicale de Liège (2001), 56(4), 239-43

Numerous observational (epidemiological surveys) or interventional (controlled trials) studies demonstrated that regular physical activity increases insulin sensitivity in normal subjects and decreases ... [more ▼]

Numerous observational (epidemiological surveys) or interventional (controlled trials) studies demonstrated that regular physical activity increases insulin sensitivity in normal subjects and decreases insulin resistance in patients with obesity and/or type 2 diabetes. These favourable effects are at least partially linked to a reduction in abdominal fat mass. This results in a significant improvement of lipid profile, with a decrease in the concentrations of total cholesterol, LDL cholesterol and triglycerides, associated with an increase of HDL cholesterol level. Such favourable metabolic effects related to regular physical activity probably explain the better cardiovascular prognosis observed in regularly exercising subjects as compared to sedentary individuals. These observations should motivate any practitioner to promote endurance physical exercise in every subject, especially in individuals at high cardiovascular risk. [less ▲]

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See detailPractical Aspects Of Computational Chemistry Calculations Through Pc Networks: The Ramses-Beowulf Implementation
Beuve-Mery, D.; Rahman, M.; Ducarme, P. et al

in Journal of Computational Chemistry (2001), 22(2), 172-7

We have built clusters of PC using up to 320 processors in parallel. The first cluster was built in 1996 from 64 computers. The parallel architectures are named RAMSES. In this article, we share our ... [more ▼]

We have built clusters of PC using up to 320 processors in parallel. The first cluster was built in 1996 from 64 computers. The parallel architectures are named RAMSES. In this article, we share our experience and discuss our choices. The architecture is composed of Pentium processors connected by a 100 Mbits/s Ethernet network. Because RAMSES are built of independent computers, the system is easily maintained, and can be modified by adding or removing machines. Two programs, which are dedicated to molecular modeling and were previously developed on single machines (OSIRIS and IMPALA), have been adapted. IMPALA models peptide and protein interaction with membranes, OSIRIS simulates an ab initio folding of globular proteins. After parallelization, each program consists of two parts: one is the human/RAMSES interface, and the second is the simulation per se. The parallel architecture is transparent for the users. Tests of the IMPALA and OSIRIS efficiencies are shown and discussed. [less ▲]

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See detailAdaptations hormono-metaboliques a l'exercice musculaire.
Scheen, André ULg; Jandrain, Bernard ULg

in Revue Médicale de Liège (2001), 56(4), 195-9

Physical exercise induces numerous metabolic and hormonal changes that may be influenced by various factors, among which the intensity and the duration of the exertion seem to play a major role besides ... [more ▼]

Physical exercise induces numerous metabolic and hormonal changes that may be influenced by various factors, among which the intensity and the duration of the exertion seem to play a major role besides the possible influence of the intake of exogenous substrates. Such modifications are necessary to satisfy the marked increase in energy demand by exercising muscles, while maintaining plasma glucose concentrations within physiological range. The purpose of the present concise review is to analyse the most important fuel-hormonal adaptations observed during short heavy muscular exercise or during prolonged exercise of moderate intensity as well as those observed after physical training in normal subjects. [less ▲]

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See detailThymic Expression of Insulin-Related Genes in an Animal Model of Autoimmune Type 1 Diabetes
Kecha-Kamoun, Ouafae; Achour, Imane; Martens, Henri ULg et al

in Diabetes/Metabolism Research & Reviews (2001), 17(2, Mar-Apr), 146-52

BACKGROUND: Insulin and multiple other autoantigens have been implicated in the pathogenesis of autoimmune type 1 diabetes, but the origin of immunological self-reactivity specifically oriented against ... [more ▼]

BACKGROUND: Insulin and multiple other autoantigens have been implicated in the pathogenesis of autoimmune type 1 diabetes, but the origin of immunological self-reactivity specifically oriented against insulin-secreting islet beta-cells remains obscure. The primary objective of the present study was to investigate the hypothesis that a defect in thymic central T-cell self-tolerance of the insulin hormone family could contribute to the pathophysiology of type 1 diabetes. This hypothesis was investigated in a classic animal model of type 1 diabetes, the Bio-Breeding (BB) rat. METHODS: The expression of the mammalian insulin-related genes (Ins, Igf1 and Igf2) was analysed in the thymus of inbred Wistar Furth rats (WF), diabetes-resistant BB (BBDR) and diabetes-prone BB (BBDP) rats. RESULTS: RT-PCR analyses of total RNA from WF, BBDP and BBDR thymi revealed that Igf1 and Ins mRNAs are present in 15/15 thymi from 2-day-old, 5-day-old and 5-week-old WF, BBDR and BBDP rats. In contrast, a complete absence of Igf2 mRNA was observed in more than 80% of BBDP thymi. The absence of detectable Igf2 transcripts in the thymus of BBDP rats is tissue-specific, since Igf2 mRNAs were detected in all BBDP brains and livers examined. Using a specific immunoradiometric assay, the concentration of thymic IGF-2 protein was significantly lower in BBDP than in BBDR rats (p<0.01). CONCLUSIONS: The present study suggests an association between the emergence of autoimmune diabetes and a defect in Igf2 expression in the thymus of BBDP rats. This tissue-specific defect in gene expression could contribute both to the lymphopenia of these rats (by impaired T-cell development) and the absence of central T-cell self-tolerance of the insulin hormone family (by defective negative selection of self-reactive T-cells). [less ▲]

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See detailModelling migration from high-density polyethylene containers into concentrated solutions used as food flavourings
Fauconnier, Marie-Laure ULg; Panhaleux, V.; Vanzeveren, E. et al

in Food Additives & Contaminants (2001), 18(11), 1040-1045

Migration from high-density polyethylene into different liquids (hexane, ethanol, lemon terpenes and their emulsions) was modelled using the response surfaces method. Polynomial equations (z = A + Bx + Cy ... [more ▼]

Migration from high-density polyethylene into different liquids (hexane, ethanol, lemon terpenes and their emulsions) was modelled using the response surfaces method. Polynomial equations (z = A + Bx + Cy + Dx(2) + Ey(2) + Fxy) were established and parameters determined for each compound. Correlation coefficients were generally > 90%. Analysis indicated that 2,4-bis(1,1-dimethylethyl) phenol, probably due to the degradation of the antioxidant additive tris(2,4- bis(1,1-dimethylethyl) phenyl) phosphite, migrated into each liquid tested, whatever the temperature. Oligomers (10-30 carbons) terminated by a vinyl group were also detected. [less ▲]

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See detailPotential impact of the main benthic amphipods on the eastern Weddell Sea shelf ecosystem (Antarctica)
Dauby, Patrick ULg; Scailteur, Yves; Chapelle, Gauthier et al

in Polar Biology (2001), 24

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See detailLivres de médecine illustrés dans l'Egypte gréco-romaine
Marganne, Marie-Hélène ULg; Istasse, Nathaël

in Medicina nei Secoli : Arte e Scienza (2001), 13(1), 1-23

The paper deals with the illustrated medical texts from Hellenism to Byzantine age. It refers particularly to the two herbaria of Tebnytis and Antinoopolis, reconstructing the history and production ... [more ▼]

The paper deals with the illustrated medical texts from Hellenism to Byzantine age. It refers particularly to the two herbaria of Tebnytis and Antinoopolis, reconstructing the history and production techniques of scientific illustrated books of antiquity. [less ▲]

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See detailReticulocyte transferrin receptor (TfR) expression and contribution to soluble TfR levels.
R'Zik, Samir ULg; Loo, Martine; Beguin, Yves ULg

in Haematologica (2001), 86(3), 244-51

BACKGROUND AND OBJECTIVES: Transferrin receptor (TfR) expression in erythroid cells is regulated by a number of factors, including iron status and erythropoietin (Epo) stimulation. However, the impact of ... [more ▼]

BACKGROUND AND OBJECTIVES: Transferrin receptor (TfR) expression in erythroid cells is regulated by a number of factors, including iron status and erythropoietin (Epo) stimulation. However, the impact of these factors on reticulocyte TfR expression in vivo has never been studied. A soluble form of TfR (sTfR) is present in serum in proportion to the mass of cellular TfR. Although sTfR shedding by reticulocytes and erythroblasts has been demonstrated in vitro, the contribution of reticulocyte TfR to serum sTfR has never been evaluated in vivo. DESIGN AND METHODS: We measured directly the total number of reticulocyte TfR in normal rats of different age and iron status, as well as in animals experiencing various conditions and treatments aimed at altering erythropoietic activity and iron status, including rHuEpo therapy, hemolytic anemia, phlebotomies, hypertransfusions, thiamphenicol-induced red cell aplasia or inflammation. In addition, we examined the impact of repeated hypertransfusions with normal, reticulocyte-poor and reticulocyte-rich blood on serum sTfR levels. RESULTS: The number of TfR molecules per reticulocyte was around 50,000 in young rats but was around 100,000 in older animals. These values remained constant in most conditions and in particular were not influenced by iron supplementation or iron overload. However, functional iron deficiency as well as rHuEpo therapy resulted in increased reticulocyte TfR expression. In addition, TfR numbers in reticulocytes were elevated in the early phase of recovery after acute hemolysis or red cell aplasia but normalized soon after. Hypertransfusion experiments clearly demonstrated that reticulocytes can contribute substantially to sTfR levels in vivo. INTERPRETATION AND CONCLUSIONS: TfR numbers are regulated in vivo by the same factors as in vitro, in particular iron deficiency and erythropoietin stimulation. Circulating reticulocytes contribute significantly to serum sTfR levels. [less ▲]

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See detailVingt ans après... Regards d'un didacticien sur l'enseignement de la littérature française de Belgique
Dumortier, Jean-Louis ULg

in Textyles : Revue des Lettres Belges de Langue Française (2001), 19

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See detailSerum soluble transferrin receptor concentration is an accurate estimate of the mass of tissue receptors.
R'Zik, Samir ULg; Beguin, Yves ULg

in Experimental hematology (2001), 29(6), 677-85

OBJECTIVE: Serum levels of the soluble transferrin receptor (sTfR) vary depending on the erythropoietic activity and iron status. In vitro, sTfR shed in the incubation medium correlates well with cellular ... [more ▼]

OBJECTIVE: Serum levels of the soluble transferrin receptor (sTfR) vary depending on the erythropoietic activity and iron status. In vitro, sTfR shed in the incubation medium correlates well with cellular TfR, but this relationship has never been established in vivo. To determine the value of serum sTfR as a quantitative marker of the body mass of tissue TfR, we designed experiments to examine the correlation between serum sTfR and tissue TfR in rats with various degrees of erythropoietic activity or iron status. MATERIALS AND METHODS: We studied changes in erythropoietic activity in normal rats as well as in animals experiencing hemolysis, phlebotomy-induced iron deficiency, transfusion- or thiamphenicol-induced erythroid aplasia, or inflammation. At the end of follow-up, ferrokinetic studies were performed and animals were sacrificed. Organs were isolated and homogenized to determine the total mass of tissue TfR from the sum of tissue solubilized TfR in the bone marrow, spleen, liver, and blood cells (direct method). An indirect method was developed to derive the corporeal mass of tissue TfR from a representative marrow sample. RESULTS: As expected, serum sTfR and total mass of tissue TfR varied as a function of iron status and erythropoiesis. Relative erythroid expansion in the spleen was greater than in the bone marrow. With the exception of phlebotomized animals, the indirect method correlated very well with direct measurements of the total mass of tissue TfR (r = 0.97, p < 0.0001). There was a close relationship between the total mass of tissue TfR and the total mass of serum sTfR (r = 0.79, p < 0.0001). Serum sTfR represented approximately 5-6% of the total mass of tissue TfR in most experimental situations, but this ratio was twice as high during iron-restricted erythropoiesis. In addition, the ratio could be higher or lower in nonsteady-state situations, because changes in tissue TfR occurred faster than those of serum sTfR. CONCLUSIONS: Serum sTfR represents a constant proportion of the total mass of tissue TfR over a wide range of erythropoietic activity. However, iron deficiency results in a higher proportion of serum sTfR, and the pace of change in serum sTfR levels is slower than that of tissue TfR mass. [less ▲]

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See detailLiquid chromatographic analysis of local anesthetics in human plasma after sample preparation by on-line dialysis. Optimization by use of experimental design
Chiap, Patrice ULg; Boulanger, Bruno ULg; Fotsing, Lucas ULg et al

in Chromatographia (2001), 53(11-12), 678-686

A fully automated method involving dialysis, clean-up and enrichment of the dialysate on a pre-column packed with a strong cation-exchange phase, and subsequent liquid chromatographic (LC) analysis with ... [more ▼]

A fully automated method involving dialysis, clean-up and enrichment of the dialysate on a pre-column packed with a strong cation-exchange phase, and subsequent liquid chromatographic (LC) analysis with UV detection at 220 nm has been developed for the determination of local anesthetics (prilocaine, mepivacaine, and bupivacaine) in human plasma. All sample-handling operations were executed automatically by means of an Asted XI system. To identify the most important conditions affecting analyte recovery from the dialysis and trace-enrichment processes, a seven-factor D-optimal design with 16 experimental points was elaborated as a screening test A four-factor D-optimal design with 24 experimental points was then used to predict and optimize analyte recovery. Derringer's desirability function was also used to deduce optimum conditions for analyte recovery and dialysis time within the experimental domain. Finally, the method developed was validated. Mean recoveries were approximately 72% for bupivacaine and approximately 67% for mepivacaine and prilocaine. The limits of quantification were 28 ng mL(-1) for bupivacaine and 25 ng mL(-1) for mepivacaine and prilocaine. [less ▲]

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See detailCombined Effects of Experimental Heavy-Metal Contamination (Cu, Zn, and CH3Hg) and Starvation on Quail's Body Condition: Parallelism with a Wild Common Guillemot (Uria aalge) Population Found Stranded at the Belgian Coast
Debacker, Virginie ULg; Rutten, Astrid; Jauniaux, Thierry ULg et al

in Biological Trace Element Research (2001), 82(1-3, Summer), 87-107

Combined effects of heavy-metal contamination (Cu, Zn, and CH3Hg) and starvation were tested on common quails (Coturnix coturnix japonica) and used as a model for comparison with a wild common guillemot ... [more ▼]

Combined effects of heavy-metal contamination (Cu, Zn, and CH3Hg) and starvation were tested on common quails (Coturnix coturnix japonica) and used as a model for comparison with a wild common guillemot (Uria aalge) population found stranded at the Belgian coast. Appropriate heavy-metal levels were given to the quails to obtain concentrations similar to those found in the seabirds's tissues. The contaminated animals were then starved for 4 d to simulate the evident malnutrition symptoms observed at the guillemot's level. In such conditions, food intake and total-body weight are shown to decrease in contaminated individuals with simultaneous significant hepatic and renal increase of the heavy-metal concentrations. Like guillemots, higher heavy-metal levels were observed in those contam- inated quails that had also developed a cachectic status characterized by a general atrophy of their pectoral muscle and complete absence of subcutaneous and/or abdominal fat depots. Although likely the result of a general protein catabolism during starvation, it is suggested that these higher metal levels could as well enhance a general muscle wasting process (cachectic status). [less ▲]

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See detailAlgebraic decay of the survival probability in chaotic helium
Schlagheck, Peter ULg; Buchleitner, A.

in Physical Review. A (2001), 63(2), 024701

We demonstrate that the classical helium atom exhibits algebraic decay of the survival probability in the autoionizing eZe configuration. Excitation towards asymptotic orbits of marginal stability is ... [more ▼]

We demonstrate that the classical helium atom exhibits algebraic decay of the survival probability in the autoionizing eZe configuration. Excitation towards asymptotic orbits of marginal stability is identified as the cause of the nonexponential decay. Since one electron travels along a bound Kepler trajectory of infinite excitation in these orbits, we argue that the classical decay law will prevail in the quantum dynamics of a wave packet launched along the eZe configuration. [less ▲]

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See detailMigraine - advances in genetic research and possible link to neurophysiological abnormalities
Sandor, Peter S.; Agosti, Reto; Schoenen, Jean ULg

in Schweizer Archiv für Neurologie, Neurochirurgie und Psychiatrie = Archives Suisses de Neurologie, Neurochirurgie et de Psychiatrie (2001), 152

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See detailA New Design of Equilibrator to Monitor Carbon Dioxide in Highly Dynamic and Turbid Environments
Frankignoulle, M.; Borges, Alberto ULg; Biondo, Renzo ULg

in Water Research (2001), 35(5), 1344-7

A new design of equilibrator for carbon dioxide monitoring in natural waters is described. It consists in a vertical tube filled with marbles through which water is flowing while equilibrating with a ... [more ▼]

A new design of equilibrator for carbon dioxide monitoring in natural waters is described. It consists in a vertical tube filled with marbles through which water is flowing while equilibrating with a closed air circuit. It offers several advantages compared with classical equilibrators, among which is a fast response time (half-life constant approximately 30 s) and the potential to work in very turbid water. The proposed equilibrator is of particular interest to monitor carbon dioxide in coastal ecosystems, such as estuaries, which are known to be turbid and highly dynamic. Two performance tests and some field results are presented to illustrate the efficiency of the proposed system. [less ▲]

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See detailCharge critique et longueur de flambement des éléments à inertie variable et aux conditions d'extrémité élastiques
Latteur, Pierre ULg

in revue scientifique des Instituts supérieurs industriels francophones de Belgique (2001), 15

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See detailQuelle évaluation externe des élèves pour quels socles de compétences ?
Bodin, A.; Delory, C.; Lafontaine, Dominique ULg et al

in Pédagogies, réformes et innovations dans l'enseignement (2001), 14

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See detailLes notions d'indices et de charges en procédure pénale
Jacobs, Ann ULg

in Revue de Jurisprudence de Liège, Mons et Bruxelles (2001)

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See detailIncidences morphodynamiques et biologiques de réaménagements de rivières : le cas de l’Ourthe occidentale à Moircy
Jonet; Petit, François ULg; Dupont, E. et al

in Bulletin de la Société Géographique de Liège (2001)

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See detailLa divinyl éther synthase de plantes
Hoyaux, P.; Fauconnier, Marie-Laure ULg; Delcarte, J. et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2001), 5(2), 79-84

Divinyl ether synthase, an enzyme of the lipoxygenase pathway transforms, in potato tubers, 9-hydroperoxides of fatty acids into colneleic and colnelenic acid, two divinyl ethers of fatty acids. The ... [more ▼]

Divinyl ether synthase, an enzyme of the lipoxygenase pathway transforms, in potato tubers, 9-hydroperoxides of fatty acids into colneleic and colnelenic acid, two divinyl ethers of fatty acids. The enzyme has been described in a limited number of quite different plants. The enzyme has also been detected in tomato roots, garlic bulbs, tobacco plants and in marine algae. The enzyme is bound to membranes and is located in the microsomal fraction. The molecular weight of the enzyme exceeds 100,000 Da, its optimal pH is around 9 and its high specificity for 9-hydroperoxides as substrate is described. The reactional mechanism has been elucidated using radio-labelled molecules. Colneleic and colnelenic acid can be degraded enzymatically or not into aldehydes and oxo-acids. Those last compounds are also formed by the action of hydroperoxide lyase on 9-hydroperoxides of fatty acids. As other enzymes of the lipoxygenase pathway, reaction products of divinyl ether synthase are involved in pathogenic resistance. Colneleic and colnelenic acid content in potato plants has been corelated with resistance to Phytophthora infestans. [less ▲]

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See detailRadiative lifetime measurements and transition probabilities of astrophysical interest in Er III
Biémont, Emile ULg; Garnir, Henri-Pierre ULg; Bastin, Thierry ULg et al

in Monthly Notices of the Royal Astronomical Society (2001), 321

Radiative lifetimes of seven excited states of Er III have been measured using time-resolved laser-induced fluorescence following two-photon excitation. Relativistic Hartree-Fock calculations taking core ... [more ▼]

Radiative lifetimes of seven excited states of Er III have been measured using time-resolved laser-induced fluorescence following two-photon excitation. Relativistic Hartree-Fock calculations taking core-polarization effects into account are found to be in excellent agreement with the experimental results. A large set of new calculated transition probabilities is presented for many transitions of astrophysical interest. These results will be useful for investigating the composition of chemically peculiar stars. [less ▲]

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See detailCurrent issues : varicella
Stouvenakers, Nadine ULg; Sadzot-Delvaux, Catherine ULg; Rentier, Bernard ULg

in Vaccines : Children and Practice (2001), 4

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See detailEffects of 8-epi-Pgf2alpha on isolated bronchial smooth muscle of healthy and heaves-affected horses
Kirschvink, Nathalie; Art, Tatiana ULg; Lekeux, Pierre ULg et al

in Journal of Veterinary Pharmacology & Therapeutics (2001), 24(3), 215-221

8-Epi-PGF2alpha, a prostaglandin-like compound generated by oxidative stress, has been shown to be an in vitro bronchoconstrictor in airways from healthy laboratory animals and healthy humans, but it has ... [more ▼]

8-Epi-PGF2alpha, a prostaglandin-like compound generated by oxidative stress, has been shown to be an in vitro bronchoconstrictor in airways from healthy laboratory animals and healthy humans, but it has never been studied in diseased airways. Here, the bronchoconstrictive capacity of 8-epi-PGF2alpha on isolated bronchial rings (BR) of healthy and heaves-affected horses was evaluated by comparing the maximal effect and the potency of 8-epi-PGF2alpha to those of (1) acetylcholine (ACh), (2) its stereoisomer PGF2alpha and (3) its synthetic receptor agonist, U46619. Furthermore, the potential capacity of 8-epi-PGF2alpha to enhance the cholinergic (ACh) responsiveness of bronchial smooth muscle was investigated. 8-Epi-PGF2alpha contracted BR with a rank order of efficacy of Ach > U44619 > PGF2alpha > 8-epi-PGF2alpha in both healthy and heaves-affected horses. The contractile maximal response elicited by 8-epi-PGF2alpha was significantly smaller than that elicited by the other drugs, but was significantly higher in BR from heaves-affected horses than in those sampled in healthy horses, whilst pD2 values were similar. A subthreshold concentration of 8-epi-PGF2alpha (10-7 M) did not induce in vitro cholinergic hyper-responsiveness in BR of either healthy or heaves-affected horses. In conclusion, it has been demonstrated that 8-epi-PGF2alpha is an in vitro bronchoconstrictor of minor importance in healthy horses, but whose efficacy is significantly increased in heaves-affected horses. [less ▲]

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See detailChanges in polyamines, auxins and peroxidase activity during in vitro rooting of Fraxinus angustifolia shoots: an auxin-independent rooting model
Tonon, Giustino; Kevers, Claire ULg; Gaspar, Thomas ULg

in Tree Physiology (2001), 21(10), 655-663

Among shoots of Fraxinus angustifolia Vahl raised in vitro, 76% rooted after culture on root induction medium for 5 days in darkness followed by culture on root expression medium for 15 days in light. The ... [more ▼]

Among shoots of Fraxinus angustifolia Vahl raised in vitro, 76% rooted after culture on root induction medium for 5 days in darkness followed by culture on root expression medium for 15 days in light. The addition of 20.7 muM indole-butyric acid (IBA) to the root induction medium did not significantly increase the rooting percentage (88%). Putrescine, spermidine, cyclohexylamine (CHA) and aminoguanidine (AG) enhanced rooting up to 100% (98.66% for AG), when applied during root induction in the absence of IBA, otherwise these compounds inhibited rooting, as did spermine and difluoromethylornithine (DFMO) + difluoromethylarginine (DFMA). The root induction phase was characterized by a temporary increase in endogenous free indole-acetic acid (IAA) and putrescine concentrations during root induction, whereas the root expression phase was characterized by increased peroxidase activity and low concentrations of polyamines. These changes were specifically associated with the rooting process and did not depend on the presence of exogenous IBA, because application of exogenous IBA enhanced the amount of IAA in the cuttings but did not affect rooting or the pattern of changes in polyamines and peroxidase. The effects of CHA, AG and DFMO + DFMA on endogenous concentrations of auxins and polyamines highlight the close relationship between the effects of IAA and putrescine in root induction and suggest that polyamine catabolism has an important role in root formation and elongation. [less ▲]

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See detailLe cas clinique du mois. Maladie de Von Hippel-Lindau.
Gaspar, Y.; de Leval, Jean ULg; Quatresooz, Pascale ULg et al

in Revue Médicale de Liège (2001), 56(2), 68-71

VHL disease is a rare genetical disease with a poor long-term prognosis. Clinical features include retineous angiomas, CNS hemangioblastomas, pheochromocytomas and renal cysts. Renal cysts are bilateral ... [more ▼]

VHL disease is a rare genetical disease with a poor long-term prognosis. Clinical features include retineous angiomas, CNS hemangioblastomas, pheochromocytomas and renal cysts. Renal cysts are bilateral and frequently lead to malignant transformation. Surgical treatment of renal cysts is preferably delayed until a minimum of 3 cm diameter has been reached. Treatment has to be as conservative as possible, knowing that uni- or bilateral nephrectomy often has to be carried out later. [less ▲]

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See detailInteractions between systemic analgesics.
Joris, Jean ULg; Kaba, Abdourahmane ULg

in Acta Anaesthesiologica Belgica (2001), 52(4), 395-401

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See detailNote de lecture - 385. Un vers de Cassius de Parme (CRF tg. fr. inc. 4 Ribbeck)
Rochette, Bruno ULg

in Latomus : Revue d'Etudes Latines (2001), 60(2, APR-JUN), 464-465

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See detailAutomatic time stepping algorithms for implicit numerical simulations of blade/casing interactions
Noels, Ludovic ULg; Stainier, Laurent ULg; Ponthot, Jean-Philippe ULg et al

in International Journal of Crashworthiness (2001), 6(3), 351-362

An automatic time stepping algorithm for non-linear problems, solved by implicit schemes, is presented. The time step computation is based on the estimation of an integration error calculated from the ... [more ▼]

An automatic time stepping algorithm for non-linear problems, solved by implicit schemes, is presented. The time step computation is based on the estimation of an integration error calculated from the acceleration difference. It is normalised according to the size of the problem and the integration parameters. This time step control algorithm modifies the time step size only if the problem has a long time physical change. Additionally, the Hessian matrix can be kept constant for several iterations, even though the problem is non-linear. A criterion selecting if the Hessian matrix must be calculated or not is developed. Finally, a criterion of iterations divergence is also proposed. It avoids the determination, by the user, of a maximal iteration number. This minimises the total number of iterations, and thus the computation cost. Industrial numerical examples are presented that demonstrate the performances (precision and computational cost) of the algorithms. [less ▲]

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See detailIrradiation du petit bassin et fonction ano-rectale.
Gervaz, P; COUCKE, Philippe ULg; Gillet, M

in Gastroentérologie Clinique et Biologique (2001), 25

Le traitement adjuvant des cancers du rectum a pour buts de stériliser la maladie résiduelle infra-clinique et d’améliorer le contrôle local. Depuis plus de 20 ans, des milliers de malades ont été inclus ... [more ▼]

Le traitement adjuvant des cancers du rectum a pour buts de stériliser la maladie résiduelle infra-clinique et d’améliorer le contrôle local. Depuis plus de 20 ans, des milliers de malades ont été inclus dans des études randomisées, visant d’abord à mettre en évidence un gain de survie et une réduction des récidives loco-régionales, en relation avec la radiothérapie pré- ou postopératoire, combinée ou non à la chimiothérapie. Les conséquences en termes de qualité de vie de ces traitements ont pourtant été peu étudiées, et la tolérance fonctionnelle du néo-rectum et de l’appareil sphinctérien à la radiothérapie restent mal connues [1]. Les difficultés liées à l’étude des effets de l’irradiation sur les tissus normaux, ainsi que la variabilité inter-individuelle de la réponse à la radiothérapie, s’ajoutent et rendent le sujet plus complexe encore. Les radiothérapeutes adaptent leur technique afin de réduire autant que possible la dose administrée aux tissus normaux avoisinant la tumeur. Dans le cas de l’irradiation du petit bassin, c’est l’intestin grêle qui a longtemps été considéré comme la structure à risque de complications, alors que l’atteinte du sphincter anal était rarement mentionnée [2]. Malgré les répercussions importantes de la dysfonction ano-rectale sur la qualité de vie des malades, l’atteinte du sphincter anal par la radiothérapie est restée un aspect négligé du traitement adjuvant des cancers du petit bassin [3]. Cet article a pour but, à travers une revue de la littérature, de mettre en évidence les effets qualitatifs et quantitatifs de la radiothérapie sur la fonction du sphincter anal, ainsi que de proposer une modification de la technique actuelle d’irradiation des cancers du bas rectum. [less ▲]

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See detailSolar Photocatalytic Destruction of p-Nitrophenol: A Pedagogical Use of Lab Wastes
Herrera-Melián, J. A.; Doña-Rodríguez, J. M.; Tello Rendón, E. et al

in Journal of Chemical Education (2001), 78(6), 775-777

In this article we propose the destruction of p-nitrophenol wastes obtained in a previous lab experiment, to generate a new lab experiment. The recommended destruction technique is solar TiO2 ... [more ▼]

In this article we propose the destruction of p-nitrophenol wastes obtained in a previous lab experiment, to generate a new lab experiment. The recommended destruction technique is solar TiO2-photocatalysis. When the effects of TiO2 and sunlight are tested separately, a slight decrease of p-nitrophenol is observed; but when TiO2 and sunlight are employed together p-nitrophenol disappears in 1 or 2 h. These experiments do not require sophisticated equipment or special lab training for the students. Groups of students tested different experimental conditions, such as the effect of different light intensities and sources (800-W UV-lamp, sunlight on sunny days, and sunlight on a cloudy day) or the addition of H2O2. p-Nitrophenol is degraded under the three light sources but at different rates. The addition of H2O2 to the TiO2-plus-sunlight system enhances p-nitrophenol degradation kinetics when compared with the TiO2 plus sunlight and H2O2 plus sunlight combinations. [less ▲]

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See detailIntegrated modelling of the Belgian Coastal Zone
Delhez, Eric ULg; Carabin, G.

in Estuarine Coastal & Shelf Science (2001), 53(4), 477-491

The management of the water resources in coastal or delta plains asks for an integrated modelling of the water system at a regional scale. In the SALMON project, detailed descriptions of the groundwater ... [more ▼]

The management of the water resources in coastal or delta plains asks for an integrated modelling of the water system at a regional scale. In the SALMON project, detailed descriptions of the groundwater, river and marine domains are provided by coupling appropriate numerical models of these different sub-systems. The application of this three-fold model to the Scheldt and Belgian Coastal Zone reveals a marked river plume extending along the Belgian Coast with strong offshore gradients. This plume cannot be explained by the Eulerian residual transport velocity field but requires Lagrangian aspects to be taken into account. The computation of the age of this water mass shows that the different parts of the coastal zone are influenced by a discharge in the Grote Schijn River after a delay that varies between a few days (for the marine part of the estuary) to about 100 days (for the centre of the residual gyre). The computation shows also that the groundwater around Antwerp can also be contaminated by a pollution in the river but the resulting mass loss from the river does not lead to a significant reduction of the flux to the coastal zone. (C) 2001 Academic Press. [less ▲]

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See detailDatabase "SIGMA Pro" information system and bibliographical management of active substances of plant protection products and biocides.
Rung, J.; Tricot, B.; Copin, A. et al

in Toegepaste Biologische Wetenschappen) (2001), 66(2b),

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See detailCysteinyl peptide inhibitors of Bacillus cereus zinc beta-lactamase.
Bounaga, S.; Galleni, Moreno ULg; Laws, A. P. et al

in Bioorganic & medicinal chemistry (2001), 9(2), 503-10

Several cysteinyl peptides have been synthesised and shown to be reversible competitive inhibitors of the Bacillus cereus metallo-beta-lactamase. The pH dependence of pKi indicates that the thiol anion ... [more ▼]

Several cysteinyl peptides have been synthesised and shown to be reversible competitive inhibitors of the Bacillus cereus metallo-beta-lactamase. The pH dependence of pKi indicates that the thiol anion displaces hydroxide ion from the active site zinc(II). D,D-Peptides bind to the enzyme better than other diastereoisomers, which is compatible with the predicted stereochemistry of the active site. [less ▲]

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See detailSurface Modification of Polycarbonate and Poly(ethyleneterephthalate) Films and Membranes by Polyelectrolyte Deposition
Dauginet, Laurence; Duwez, Anne-Sophie ULg; Legras, Roger et al

in Langmuir (2001), 17

The surface modification by chemical or physical adsorption of a polyelectrolyte (polyallylamine, PAH) was established using hydrolyzed polycarbonate (PC) and poly(ethylene terephthalate) (PET) thick and ... [more ▼]

The surface modification by chemical or physical adsorption of a polyelectrolyte (polyallylamine, PAH) was established using hydrolyzed polycarbonate (PC) and poly(ethylene terephthalate) (PET) thick and thin films. Contact angle data indicated changes in the hydrophilicity of PET film surfaces in terms of the chemical treatment. XPS analysis showed that the immobilization of PAH on PET and PC films was effective and that the amount of chemically or/and physically bounded PAH depends on the pH of the electrolyte solution used for the adsorption. Similar treatments have been successfully applied to polymeric track-etched membranes. These modified membranes have been used as templates for the synthesis of polypyrrole (PPy) nanotubules. FE-SEM analysis showed that much thicker PPy tubules were obtained in modified membranes than in virgin ones. This indicates that the surface chemistry of the pore walls plays an important role in the morphology of the nanostructures synthesized within the pores [less ▲]

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See detailThe ATP-gated P2X1 ion channel acts as a positive regulator of platelet responses to collagen.
Oury, Cécile ULg; Toth-Zsamboki, Emese; Thijs, Chantal et al

in Thrombosis and Haemostasis (2001)

This study shows that, during collagen-initiated platelet activation, the early secretion of ATP results in the activation of the P2X1 ion channel, which plays a role as a positive regulator of further ... [more ▼]

This study shows that, during collagen-initiated platelet activation, the early secretion of ATP results in the activation of the P2X1 ion channel, which plays a role as a positive regulator of further platelet responses. [less ▲]

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See detailModelling of friction and wear for designing cryogenic valves
Bozet, Jean-Luc ULg

in Tribology International (2001), 34(4), 207-215

From a tribological point of view, the selection of materials for seals for valves of cryogenic rocket engines is a critical issue for the designer. Due to the lack of comprehensive information on this ... [more ▼]

From a tribological point of view, the selection of materials for seals for valves of cryogenic rocket engines is a critical issue for the designer. Due to the lack of comprehensive information on this topic. data have been obtained in the framework of research programmes. In the first step, two polymers potentially usable for sealing cryogenic fluids were identified, They were submitted to general test conditions to gain some fundamental understanding of their tribological behaviour when immersed in a cryogenic fluid. This fundamental understanding proved to be helpful for an efficient technical approach. This approach with the test conditions as close as possible to those met in real valves has been used in the second step. In order to obtain the best information with the minimum number of tests, the statistical method of Doehlert has been adopted. The use of such a method led to the construction of surface response for modelling friction and wear. These surfaces and their associated equation are directly and easily usable by the designer, This way of treating technical tribological problem is illustrated by an example. (C) 2001 Elsevier Science Ltd. All rights reserved. [less ▲]

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See detailUretere retrocave chez un enfant de dix ans.
Kakanou, A.; NCHIMI LONGANG, Alain ULg; Ghuysen, M. S. et al

in Annales de Chirurgie (2001), 126(2), 156-8

Retrocaval ureter is an uncommon abnormality of the inferior vena cava, which is rarely detected in the child due to its non-specific symptomatology. Despite a varying state of severity, chronic ureteral ... [more ▼]

Retrocaval ureter is an uncommon abnormality of the inferior vena cava, which is rarely detected in the child due to its non-specific symptomatology. Despite a varying state of severity, chronic ureteral obstruction generally leads to the deterioration of renal function during adulthood. Treatment depends on the symptomatology in question, and surgical management should be as conservative as possible. [less ▲]

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See detailCharacterization of OXA-29 from Legionella (Fluoribacter) gormanii: molecular class D beta-lactamase with unusual properties.
Franceschini, N.; Boschi, L.; Pollini, S. et al

in Antimicrobial agents and chemotherapy (2001), 45(12), 3509-16

A class D beta-lactamase determinant was isolated from the genome of Legionella (Fluoribacter) gormanii ATCC 33297(T). The enzyme, named OXA-29, is quite divergent from other class D beta-lactamases ... [more ▼]

A class D beta-lactamase determinant was isolated from the genome of Legionella (Fluoribacter) gormanii ATCC 33297(T). The enzyme, named OXA-29, is quite divergent from other class D beta-lactamases, being more similar (33 to 43% amino acid identity) to those of groups III (OXA-1) and IV (OXA-9, OXA-12, OXA-18, and OXA-22) than to other class D enzymes (21 to 24% sequence identity). Phylogenetic analysis confirmed the closer ancestry of OXA-29 with members of the former groups. The OXA-29 enzyme was purified from an Escherichia coli strain overexpressing the gene via a T7-based expression system by a single ion-exchange chromatography step on S-Sepharose. The mature enzyme consists of a 28.5-kDa polypeptide and exhibits an isoelectric pH of >9. Analysis of the kinetic parameters of OXA-29 revealed efficient activity (k(cat)/K(m) ratios of >10(5) M(-1) x s(-1)) for several penam compounds (oxacillin, methicillin, penicillin G, ampicillin, carbenicillin, and piperacillin) and also for cefazolin and nitrocefin. Oxyimino cephalosporins and aztreonam were also hydrolyzed, although less efficiently (k(cat)/K(m) ratios of around 10(3) M(-1) x s(-1)). Carbapenems were neither hydrolyzed nor inhibitory. OXA-29 was inhibited by BRL 42715 (50% inhibitory concentration [IC(50)], 0.44 microM) and by tazobactam (IC(50), 3.2 microM), but not by clavulanate. It was also unusually resistant to chloride ions (IC(50), >100 mM). Unlike OXA-10, OXA-29 was apparently found as a dimer both in diluted solutions and in the presence of EDTA. Its activity was either unaffected or inhibited by divalent cations. OXA-29 is a new class D beta-lactamase that exhibits some unusual properties likely reflecting original structural and mechanistic features. [less ▲]

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See detailExperimental And Conformational Analyses Of Interactions Between Butenafine And Lipids
Mingeot-Leclercq, Mp.; Gallet, X.; Flore, Christelle ULg et al

in Antimicrobial Agents and Chemotherapy (2001), 45(12), 3347-54

Butenafine (N-4-tert-butylbenzyl-N-methyl-1-naphtalenemethylamine hydrochloride) is an antifungal agent of the benzylamine class that has excellent therapeutic efficacy and a remarkably long duration of ... [more ▼]

Butenafine (N-4-tert-butylbenzyl-N-methyl-1-naphtalenemethylamine hydrochloride) is an antifungal agent of the benzylamine class that has excellent therapeutic efficacy and a remarkably long duration of action when applied topically to treat various mycoses. Given the lipophilic nature of the molecule, efficacy may be related to an interaction with cell membrane phospholipids and permeabilization of the fungal cell wall. Similarly, high lipophilicity could account for the long duration of action, since fixation to lipids in cutaneous tissues might allow them to act as local depots for slow release of the drug. We have therefore used computer-assisted conformational analysis to investigate the interaction of butenafine with lipids and extended these observations with experimental studies in vitro using liposomes. Conformational analysis of mixed monolayers of phospholipids with the neutral and protonated forms of butenafine highlighted a possible interaction with both the hydrophilic and hydrophobic domains of membrane phospholipids. Studies using liposomes demonstrated that butenafine increases membrane fluidity [assessed by fluorescence polarization of 1-(4-trimethylammonium-phenyl)-6-phenyl-1,3,5-hexatriene and 1,6-diphenylhexatriene] and membrane permeability (studied by release of calcein from liposomes). The results show, therefore, that butenafine readily interacts with lipids and is incorporated into membrane phospholipids. These findings may help explain the excellent antifungal efficacy and long duration of action of this drug when it is used as a topical antifungal agent in humans. [less ▲]

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See detailLa recherche de l'environnement pertinent, contribution à une géographie du sensible
Schmitz, Serge ULg

in Espace Géographique (L') (2001), 30(4), 321-332

Which factors heighten sensitivity to environmental changes? The answer to this question is of interest to everyone who acts on the environment. However, methods and concepts still need to be explored ... [more ▼]

Which factors heighten sensitivity to environmental changes? The answer to this question is of interest to everyone who acts on the environment. However, methods and concepts still need to be explored before a geography of sensibility could respond to this deman. This paper presens the methodological contributions and results of an exploratory study of the sensibilities of 65 residents of a Belgian rural municipality. Factors related to the environmental change, to the individual and to the relantionship between the individual and place are analysed. [less ▲]

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See detailComparison between the GIRBAS Scale and the Acoustic and Aerodynamic Measures Provided by EVA for the Assessment of Dysphonia following Unilateral Vocal Fold Paralysis.
Morsomme, Dominique ULg; Jamart, Jacques; Wery, Carine et al

in Folia Phoniatrica et Logopaedica (2001), 53(6), 317-25

The aim of this study is to establish relevant objective parameters for evaluating dysphonia following unilateral vocal fold paralysis. To do so, the study compares objective and perceptual voice measures ... [more ▼]

The aim of this study is to establish relevant objective parameters for evaluating dysphonia following unilateral vocal fold paralysis. To do so, the study compares objective and perceptual voice measures. The objective measures were obtained using a voice analysis software (Evaluation Vocale Assistee), whereas the perceptual measures were established with the GIRBAS Scale (grade, instability, roughness, breathiness, asthenia, and strain). All measurements were performed on 40 voice samples: 28 dysphonic subjects with unilateral laryngeal paralysis, and 12 control subjects. The intra- and inter-judge agreements were fairly good, at least for control subjects. The six GIRBAS measures obtained from the pathological voices were higher than those from the control voices (p < 0.001) and the correlation between both groups was good. Grade, breathiness and asthenia correlated with the objective parameters that express the aperiodicity of the phonatory signal (p < 0.01), namely, the coefficient of variability of the fundamental frequency, the coefficient of variability of intensity, and jitter. Our findings suggest that the perceptual reality of laryngeal paralysis-induced dysphonia depends more on grade, breathiness and asthenia than it does on roughness or instability. [less ▲]

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See detailHollow atoms : a theoretical challenge
Vaeck, N; Hansen, J E; Palmeri, P et al

in Physica Scripta (2001), T95

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See detailGap Filling Strategies For Defensible Annual Sums Of Net Ecosystem Exchange
Falge, E.; Baldocchi, D.; Olson, R. et al

in Agricultural and Forest Meteorology (2001), 107(1),

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See detailAdding olanzapine to venlafaxine in treatment-refractory non-psychotic chronic depression
PITCHOT, William ULg; ANSSEAU, Marc ULg

in American Journal of Psychiatry (The) (2001)

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See detailA Parametric Distance Function Approach for Malmquist Productivity Index Estimation
Fuentes, Hugo J.; Grifell-Tatjé, Emili; Perelman, Sergio ULg

in Journal of Productivity Analysis (2001), 15

Malmquist indexes of productivity are generally estimated using index number techniques or non-parametric frontier approaches. The aim of this paper is to showthat Malmquist indexes can be estimated in a ... [more ▼]

Malmquist indexes of productivity are generally estimated using index number techniques or non-parametric frontier approaches. The aim of this paper is to showthat Malmquist indexes can be estimated in a similar way using parametric-deterministic or parametric-stochastic frontier approaches. To allow a multi-output multi-input technology and for technical change in production, we adopt an output distance function which is specified in a translog form. We then show that using the estimated parameters, several radial distance functions can be calculated and combined in order to estimate and decompose the productivity index. Finally, this approach is applied to a panel of Spanish insurance companies. The main results confirm those generally obtained for financial services: very low rates of growth and technical change in spite of a rapid deregulation process and expansion of activity. [less ▲]

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See detailDe PCB/dioxine vergiftiging in België (1999): analyse van de gezondheidsrisico’s
Bernard, A.; Broekaert, F.; De Poorter, G. et al

in Vlaams Diergeneeskundig Tijdschrift (2001), 70

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See detailDefict in recognition of emotional facial expression are still oresent in alcoholics after mid to long term abstinence
Kornreich, C; Blairy, Sylvie ULg; Philippot, P et al

in Journal of Studies on Alcohol (2001), 62(4), 533-542

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See detailThe early Paleozoic carbon cycle
Godderis, Y.; François, Louis ULg; Veizer, J.

in Earth And Planetary Science Letters (2001), 190(3-4), 181-196

A review of O, C, Sr and S isotope trends for the entire Phanerozoic shows that the present-day values of isotope signals are similar to those at the Proterozoic termination. The sharp rise in Sr-87/Sr-86 ... [more ▼]

A review of O, C, Sr and S isotope trends for the entire Phanerozoic shows that the present-day values of isotope signals are similar to those at the Proterozoic termination. The sharp rise in Sr-87/Sr-86 since similar to 65 Ma has been attributed to an uplift and subsequent metamorphism and erosion associated with the Himalayas and Tibet. This orogenic evolution has been postulated to have influenced the global organic and inorganic carbon cycles and climate as well. A similar large-scale orogeny, the Pan-African event, also dominated the Neoproterozoic (Vendian) times, and the similarity of modern and Neoproterozoic isotope values for seawater may therefore have had a comparable tectonic cause. In this contribution, we present the results of a numerical model of the coupled C-alkalinity-S-Sr cycles suggesting that the early Paleozoic (from early Cambrian to late Devonian) evolution of Sr, O, C and S seawater isotope signals could have been the consequence of progressive oxidation of a large reduced carbon reservoir exhumed during the Pan-African orogeny. The delta O-18 measured in brachiopod shells is used as a forcing of the model, postulating that any change in the oxygen isotopic composition of seawater is the result of a disequilibrium in the organic carbon subcycle through the coupling of the oxygen isotopic and carbon cycles. The calculated delta C-13, Sr-87/Sr-86 and delta S-34 are in good agreement with the data, as is the reasonable calculated history for atmospheric pCO(2) and its relation to global climate. (C) 2001 Elsevier Science B.V. All rights reserved. [less ▲]

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See detailContrôle pharmacologique de l’hyperglycémie postprandiale
SCHEEN, André ULg; JANDRAIN, Bernard ULg; PAQUOT, Nicolas ULg et al

in Médecine et Hygiène (2001), 59

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See detailPrediction Of Membrane Protein Orientation In Lipid Bilayers: A Theoretical Approach
Basyn, F.; Charloteaux, Benoît ULg; Thomas, Annick ULg et al

in Journal of Molecular Graphics & Modelling (2001), 20(3), 235-44

Over the past few years, several three-dimensional (3-D) structures of membrane proteins have been described with increasing accuracy, but their relationship with membranes are still not well understood ... [more ▼]

Over the past few years, several three-dimensional (3-D) structures of membrane proteins have been described with increasing accuracy, but their relationship with membranes are still not well understood. Recently, we have developed an empirical method, Integral Membrane Protein and Lipid Association (IMPALA), to predict the insertion of molecules (lipids, drugs) into lipid bilayers (Proteins 30 (1998) 357). The IMPALA uses a Monte Carlo minimisation procedure to calculate the depth and the angle of insertion of membrane-interacting molecules taking into account the restraints dictated by a lipid bilayer. In this paper, we use IMPALA to test the insertion of 23 integral membranous proteins (IMPs) and 2 soluble proteins into membranes. Four IMP are studied in detail: OmpA, maltoporin, MsCl channel and bacteriorhodopsin. The 3-D structures of the proteins are kept constant and the insertion into membrane is monitored by minimising the value of the restraint representing the sum of two terms, one for lipid perturbation and the other for hydrophobicity. The two soluble proteins are rejected from the membrane whereas, under the same conditions, all the membrane proteins remain inside, if the solvent accessible surface of the amino acids located inside the pore of porins is ignored. The results give the tilt angle of the IMP helices or strands with respect to the membrane surface and the depth of the protein mass centre insertion. We conclude that the restraint terms of IMPALA could be used to study the insertion of model structures or complexes of proteins within membranes. [less ▲]

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See detailDiagnostic et suivi d'une large fistule porto-cave intrahepatique chez un nouveau-ne.
NCHIMI LONGANG, Alain ULg; Khamis, J.; Langhendries, J. P. et al

in Journal de Radiologie (2001), 82(11), 1642-4

Portocaval fistulas are rare and only exceptionally discovered in newborns. We report the case of a large portocaval fistula associated with portal hypoperfusion detected at Doppler US imaging in an ... [more ▼]

Portocaval fistulas are rare and only exceptionally discovered in newborns. We report the case of a large portocaval fistula associated with portal hypoperfusion detected at Doppler US imaging in an otherwise asymptomatic 5 week old infant. The patient remained asymptomatic over the following two years. At that time, preoperative angiogram showed a normal portal venous system and the fistula was surgically closed. Postoperative US showed a normal and patent portal system, without evidence of portal hypertension. [less ▲]

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See detailL'etude clinique du mois. L'etude CALM ou interet de combiner un inhibiteur de l'enzyme de conversion et un antagoniste du recepteur de type 1 de l'angiotensine II dans le traitement de la nephropathie diabetique.
Philips, Jean-Christophe ULg; Weekers, Laurent ULg; Scheen, André ULg

in Revue Médicale de Liège (2001), 56(2), 126-8

The main objective of the CALM (Candesartan And Lisinopril Microalbuminuria) study is to assess the effect of a dual blockade of the renin-angiotensin system--using both an angiotensin converting enzyme ... [more ▼]

The main objective of the CALM (Candesartan And Lisinopril Microalbuminuria) study is to assess the effect of a dual blockade of the renin-angiotensin system--using both an angiotensin converting enzyme inhibitor (ACE-I) and an angiotensin II type 1 receptor blocker--in patients with type 2 diabetes, high blood pressure and microalbuminuria. The study included 200 patients randomized to receive candesartan 16 mg or lisinopril 20 mg for 12 weeks, followed by 12 weeks of the same monotherapy or a combination treatment. Main outcomes are the reduction of microalbuminuria and blood pressure. All three of the treatments are effective, but the dual blockade is respectively 18%, 8 mmHg and 5 mmHg more effective in reducing microalbuminuria, systolic and diastolic blood pressure. No comparison is made between this "new" association and the more frequently used biotherapy (i.e. ACE-I plus thiazidic diuretic) and therefore its usefulness in regular practice is still to be determined. [less ▲]

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See detailLes régimes d’épargne protéique dans le traitement de l’obésité
PAQUOT, Nicolas ULg

in Nutrition Clinique et Metabolisme (2001), 15

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See detailNew Insights into Pervaporation Mass Transport under Increasing Downstream Pressure Conditions: Critical Role of Inert Gas Entrance.
Vallières, Cécile; Favre, Eric; Roizard, Denis et al

in Industrial & Engineering Chemistry Research (2001), 40

The influence of the total downstream pressure on the pervaporation flux of a pure compound through a dense polymer membrane has been the subject to controversial debates recently. Experimental arguments ... [more ▼]

The influence of the total downstream pressure on the pervaporation flux of a pure compound through a dense polymer membrane has been the subject to controversial debates recently. Experimental arguments in favor of either the solution−diffusion model or the newly proposed pore-flow model are alternatively reported on different systems. To critically reexamine this debate, an experimental study under controlled downstream conditions has been performed for pure methanol and pure 2-propanol pervaporation through a poly(dimethylsiloxane) film, the latter having been previously reported to follow pore-flow model predictions. It is shown that a rational analysis of the effects of the downstream pressure on the results can be achieved according to the classical solution−diffusion model, provided that the influence of air leaks in the installation is properly taken into account. Based on this observation, the implications of an inert gas contribution, generally speaking, on pervaporation operation are discussed. [less ▲]

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See detailContinued benefit of coronary stenting versus balloon angioplasty: five-year clinical follow-up of Benestent-I trial.
Kiemeneij, F.; Serruys, P. W.; Macaya, C. et al

in Journal of the American College of Cardiology (2001), 37(6), 1598-603

OBJECTIVES: This study sought to establish whether the early favorable results in the Benestent-I randomized trial comparing elective Palmaz-Schatz stent implantation with balloon angioplasty in 516 ... [more ▼]

OBJECTIVES: This study sought to establish whether the early favorable results in the Benestent-I randomized trial comparing elective Palmaz-Schatz stent implantation with balloon angioplasty in 516 patients with stable angina pectoris are maintained at 5 years. BACKGROUND: The size of the required sample was based on a 40% reduction in clinical events in the stent group. Seven months and one-year follow-up in this trial showed a decreased incidence of restenosis and clinical events in patients randomized to stent implantation. METHODS: Data at five years were collected by outpatient visit, via telephone and via the referring cardiologist. Three patients in the stent group and one in the percutaneous transluminal coronary angioplasty (PTCA) group were lost to follow-up at five years. Major clinical events, anginal status and use of cardiac medication were recorded according to the intention to treat principle. RESULTS: No significant differences were found in anginal status and use of cardiac medication between the two groups. In the PTCA group, 27.3% of patients underwent target lesion revascularization (TLR) versus 17.2% of patients in the stent group (p = 0.008). No significant differences in mortality (5.9% vs. 3.1%), cerebrovascular accident (0.8% vs. 1.2%), myocardial infarction (9.4% vs. 6.3%) or coronary bypass surgery (11.7% vs. 9.8%) were found between the stent and PTCA groups, respectively. At five years, the event-free survival rate (59.8% vs. 65.6%; p = 0.20) between the stent and PTCA groups no longer achieved statistical significance. CONCLUSIONS: The original 10% absolute difference in TLR in favor of the stent group has remained unchanged at five years, emphasizing the long-term stability of the stented target site. [less ▲]

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See detailImproving the bias/variance tradeoff of decision trees - towards soft tree induction
Geurts, Pierre ULg; Olaru, Cristina; Wehenkel, Louis ULg

in Engineering intelligent systems (2001), 9

One of the main difficulties with standard top down induction of decision trees comes from the high variance of these methods. High variance means that, for a given problem and sample size, the resulting ... [more ▼]

One of the main difficulties with standard top down induction of decision trees comes from the high variance of these methods. High variance means that, for a given problem and sample size, the resulting tree is strongly dependent on the random nature of the particular sample used for training. Consequently, these algorithms tend to be suboptimal in terms of accuracy and interpretability. This paper analyses this problem in depth and proposes a new method, relying on threshold softening, able to significantly improve the bias/variance tradeoff of decision trees. The algorithm is validated on a number of benchmark problems and its relationship with fuzzy decision tree induction is discussed. This sheds some light on the success of fuzzy decision tree induction and improves our understanding of machine learning, in general. [less ▲]

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See detailStand der osteoporose-Therapie. Ein Medizinischer Skandal
Reginster, Jean-Yves ULg

in MMW Fortschritte der Medizin (2001), 143(14), 43

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See detailThe Cloninger's biosocial model of personality
Hansenne, Michel ULg

in Année Psychologique (L') (2001), 101(1), 155-181

In this review, the author proposes a synthesis of the biosocial model of personality developed by Cloninger. This model is based on several neurobiological and clinical hypotheses. According to this ... [more ▼]

In this review, the author proposes a synthesis of the biosocial model of personality developed by Cloninger. This model is based on several neurobiological and clinical hypotheses. According to this model, the personality is described by 4 temperaments (novelty seeking, harm avoidance, reward dependence, and persistence) which are independently heritable and related to specific central neurotransmitters, and 3 characters (self-directedness, cooperativeness, and self-transcendence) that mature in adulthood. TCI (Temperament and Character Inventory) is a 226-item self questionnaire developed by Cloninger to assess the 7 dimensions of personality. The relationships between temperaments and neurotransmitters is particularly relevant in research and in clinical practice. From a clinical point of view, the model provides a foundation for integrating diagnosis and treatment planning, including both psychotherapy and pharmacotherapy. This review discuss the advantages and the limitations of this model and proposes some future directions. [less ▲]

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See detailProgramme international pour le suivi des acquis des élèves (PISA) de l'OCDE
Lafontaine, Dominique ULg; Baye, Ariane ULg; Matoul, Anne ULg

in Cahiers du Service de Pédagogie Expérimentale (SPE) (2001), 7-8(7-8), 53-57

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See detailDe Bergson à Merleau-Ponty : pour une anthropologie de la mémoire
Frère, Bruno ULg

in Réseaux : Revue Interdisciplinaire de Philosophie Morale et Politique (2001), 18

On l'a dit et redit, la description de la mémoire par H. Bergson renvoie essentiellement, sinon à la mise en scène d'un mécanisme individuel clos et hermétique, en tout cas à l'aperçu d'une élaboration ... [more ▼]

On l'a dit et redit, la description de la mémoire par H. Bergson renvoie essentiellement, sinon à la mise en scène d'un mécanisme individuel clos et hermétique, en tout cas à l'aperçu d'une élaboration strictement "psychologique" de souvenirs que tout au plus "des mots permettent d'exprimer". Il n'est dès lors pas étonnant qu'à cet égard, Bergson n'ait pas vu "que notre mémoire se ressaisit, au fur et à mesure que nous avançons, (...) sous une forme nouvelle" au sein de cadres sociaux dont l'évolution n'a de cesse de restructurer les souvenirs qui la composent. Selon Halbwachs, "il n'est pas de souvenir qui puisse être dit purement intérieur, c'est-à-dire qui ne puisse se conserver que dans la mémoire individuelle". Ce que le sociologue reproche ainsi au philosophe c'est de ne pas tenir compte du fait qu'un "souvenir reproduit avant tout une perception collective". De ce fait, sa pensée ne permettrait nullement de composer avec la dimension sociale des souvenirs puisqu'ils appartiendraient en propre à divers psychismes hétérogènes qui, du point de vue de ceux qui les observent, se trouvent séparés et isolés "comme par une multitude de cloisons étanches". Ce que nous souhaitons suggérer ici n'est pas, à proprement parler, une nouvelle lecture "exhaustive" de Matière et mémoire qui prétendrait sauver Bergson de la critique sociologique dorénavant consacrée d'Halbwachs. L'ambition de ces lignes sera plutôt d'envisager la manière dont le dernier Merleau-Ponty, s'interrogeant sur l'importance décisive de ce qu'il nomme "le monde culturel", nous autorise à envisager une conception de la mémoire qui réserverait une place réelle à l'altérité tout en se réclamant d'une forme de bergsonisme sensiblement renouvelée et tout en inscrivant ses thèses sur un même terrain philosophique. [less ▲]

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See detailCompact and portable holographic camera using photorefractive crystals. Application in various metrological problems
Georges, Marc ULg; Scauflaire, Véronique; Lemaire, Philippe

in Applied Physics B : Lasers & Optics (2001), 72

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See detailAarabia, a new Early Devonian vascular plant from Africa (Morocco).
Gerrienne, Philippe ULg; Meyer-Berthaud, Brigitte

in Review of Palaeobotany and Palynology (2001), 116

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See detailErosion of Deccan Traps determined by river geochemistry: impact on the global climate and the Sr-87/Sr-86 ratio of seawater
Dessert, C.; Dupre, B.; François, Louis ULg et al

in Earth And Planetary Science Letters (2001), 188(3-4), 459-474

The impact of the Deccan Traps on chemical weathering and atmospheric CO2 consumption on Earth is evaluated based on the study of major elements, strontium and Sr-87/Sr-86 isotopic ratios of the main ... [more ▼]

The impact of the Deccan Traps on chemical weathering and atmospheric CO2 consumption on Earth is evaluated based on the study of major elements, strontium and Sr-87/Sr-86 isotopic ratios of the main rivers flowing through the traps, using a numerical model which describes the coupled evolution of the chemical cycles of carbon. alkalinity and strontium and allows one to compute the variations in atmospheric pCO(2), mean global temperature and the Sr-87/Sr-86 isotopic ratio of seawater, in response to Deccan trap emplacement. The results suggest that the rate of chemical weathering of Deccan Traps (21-63 t/km(2)/yr) and associated atmospheric CO consumption (0.58-2.54 x 10(6) mol C/km(2)/yr) are relatively high compared to those linked to other basaltic regions. Our results on the Deccan and available data from other basaltic regions show that runoff and temperature are the two main parameters which control the rate of CO2 consumption during weathering of basalts, according to the relationship: f = R-f x C(0)exp[-Ea/R(1/T-1/298)] where f is the specific CO2 consumption rate (mol/km(2)/yr), R-f is runoff (mm/yr), C-0 is a constant (= 1764 mu mol/l), Ea represents an apparent activation energy for basalt weathering (with a value of 42.3 kJ/mol determined in the present study), R is the gas constant and T is the absolute temperature (K-o). Modelling results show that emplacement and weathering of Deccan Traps basalts played an important role in the geochemical cycles of carbon and strontium. In particular, the traps led to a change in weathering rate of both carbonates and silicates, in carbonate deposition on seafloor, in Sr isotopic composition of the riverine flux and hence a change in marine Sr isotopic composition. As a result, Deccan Traps emplacement was responsible for a strong increase of atmospheric pCO(2) by 1050 ppmv followed by a new steady-state pCO(2) lower than that in pre-Deccan times by 57 ppmv, implying that pre-industrial atmospheric pCO(2) would have been 20% higher in the absence of Deccan basalts. pCO(2) evolution was accompanied by a rapid warming of 4 degreesC, followed after 1 Myr by a global cooling of 0.55 degreesC. During the warming phase, continental silicate weathering is increased globally. Since weathering of continental silicate rocks provides radiogenic Sr to the ocean, the model predicts a peak in the Sr-87/Sr-86 ratio of seawater following the Deccan Traps emplacement. The amplitude and duration of this spike in the Sr isotopic signal are comparable to those observed at the Cretaceous-Tertiary boundary. The results of this study demonstrate the important control exerted by the emplacement and weathering of large basaltic provinces on the geochemical and climatic changes on Earth. (C) 2001 Elsevier Science B.V. All rights reserved. [less ▲]

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See detailDistance correlations and dynamics of liquid GeSe: An ab initio molecular dynamics study
Raty, Jean-Yves ULg; Godlevsky, V. V.; Gaspard, Jean-Pierre ULg et al

in Physical Review. B, Condensed Matter and Materials Physics (2001), 64

We analyze the structure and dynamics of semiconducting liquid GeSe using ab initio molecular-dynamics simulations. We show the local order of the liquid to be close to that of the low-temperature ... [more ▼]

We analyze the structure and dynamics of semiconducting liquid GeSe using ab initio molecular-dynamics simulations. We show the local order of the liquid to be close to that of the low-temperature crystalline phase. alpha -GeSe. In particular, we show that the Peierls distortion, which defines the a phase and vanishes in the high-temperature beta crystalline phase, reenters GeSe in the melt. Examining the distance histograms allows one to analyze the Ge environment as consisting of a Gese(3) unit and having one Ge-Ge defective bond. Evidence is presented that Peierls distortion is directly responsible for the semiconducting behavior of the melt. The calculated viscosity and electrical conductivity are in agreement with the experiment. An additional neutron-diffraction experiment indicates that this liquid structure is unmodified 200 K above the melting point. [less ▲]

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See detailShelf-slope exchanges associated with a steep submarine canyon off Calvi (Corsica, NW Mediterranean Sea): A modelling approach
Skliris, Nikos; Goffart, Anne ULg; Hecq, Jean-Henri ULg et al

in Journal of Geophysical Research (2001), 106(C9), 19883-19901

A three-dimensional, unsteady, nonlinear, high-resolution model is used to investigate the impact of the Calvi Canyon (NW Corsica) steep topography on the shelf-slope exchanges as well as on the ... [more ▼]

A three-dimensional, unsteady, nonlinear, high-resolution model is used to investigate the impact of the Calvi Canyon (NW Corsica) steep topography on the shelf-slope exchanges as well as on the circulation in the Calvi Bay in homogeneous winter and early spring conditions. A double σ coordinate system is considered in order to represent adequately the high depth gradients within the canyon. The studied region is under the influence of the West Corsica Current flowing northeastward along the NW Corsican coast (right-bounded flow). Model results show that the circulation in the Calvi Bay is determined by flow modifications in the canyon area. The mean horizontal flow is deviated southwestward upstream of the canyon to form an anticyclonic gyre in the western part of the Calvi Bay. Within the canyon the circulation is cyclonic leading to an offshore flow downstream of the canyon. Around the canyon rim, the cross-shelf currents become important, indicating that this region acts as a transition zone of high exchange between nearshore and offshore areas. Furthermore, the canyon topography generates high downwelling (upwelling) and downsloping (upsloping) velocities responsible for an intense vertical transport of material in the area. Numerical runs are performed for typical prevailing wind conditions. The wind is responsible for a drastic increase of cross-shore transports between the bay and the canyon area (3–4 times larger than in the no-wind case). SW winds induce a further enhancement of cross-shelf exchanges, whereas the effect of N-NE winds is to reduce exchange at the shelf break apart from the canyon head where an intense offshore flow occurs. Within the canyon, high vertical velocities are shown to be associated with high cyclonic vorticity which is enhanced (reduced) by the N-NE (SW) wind event. A comparison between model results and measured distributions of nitrate and chlorophyll a concentrations in the area shows the role played by this specific hydrodynamics as a strong constraint on the coastal pelagic ecosystem. [less ▲]

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See detailModelling short-term CO2 fluxes and long-term tree growth in temperate forests with ASPECTS
Rasse, Daniel P.; François, Louis ULg; Aubinet, Marc ULg et al

in Ecological Modelling (2001), 141(1-3), 35-52

The net ecosystem exchange (NEE) Of CO2 between temperate forests and the atmosphere governs both carbon removal from the atmosphere and forest growth. In recent years, many experiments have been ... [more ▼]

The net ecosystem exchange (NEE) Of CO2 between temperate forests and the atmosphere governs both carbon removal from the atmosphere and forest growth. In recent years, many experiments have been conducted to determine temperate forest NEE. These data have been used by forest modellers to better understand the processes that govern CO, fluxes, and estimate the evolution of these fluxes under changing environmental conditions. Nevertheless, it is not clear whether models capable of handling short-term processes, which are mostly source-driven, can provide an accurate estimate of long-term forest growth, which is potentially more influenced by sink- and phenology-related processes. To analyse the interactions between short- and long-term processes, we developed the ASPECTS model, which predicts long-term forest growth by integrating, over time, hourly NEE estimates. Validation data consisting of measurements of NEE by eddy-covariance and forest carbon reservoir estimates were obtained from mixed deciduous and evergreen experimental forests located in Belgium. ASPECTS accurately estimated both: (1) the NEE fluxes for several years of data; and (2) the amount of carbon contained in stems, branches, leaves, fine and coarse roots. Our simulations demonstrated that: (1) NEE measurements in Belgian forests are compatible with forest growth over the course of the 20th century, and (2) that forest history and long-term processes need to be considered for accurate simulation of short-term CO2 fluxes. [less ▲]

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See detailSecret professionnel, confidentialité et juriste d'entreprise : la nouvelle donne
Thirion, Nicolas ULg; Benoit-Moury, Anne

in Journal des Tribunaux (2001)

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See detailEtude de la diversité et des plantes hôtes des Coccinellidae de Belgique
Francis, Frédéric ULg

in Notes Fauniques de Gembloux (2001), 44

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See detailInfluence of temperature during cardiopulmonary bypass on leukocyte activation, cytokine balance, and post-operative organ damage
Qing, M.; Vazquez-Jimenez, J. F.; Klosterhalfen, B. et al

in Shock (Augusta, Ga.) (2001), 15(5), 372-7

This study examined the hypothesis that core temperature (T(o)) during cardiopulmonary bypass (CPB) influences the perioperative systemic inflammatory response and post-operative organ damage. Twenty-four ... [more ▼]

This study examined the hypothesis that core temperature (T(o)) during cardiopulmonary bypass (CPB) influences the perioperative systemic inflammatory response and post-operative organ damage. Twenty-four pigs were assigned to a T(o) regimen during CPB: normothermia (T(o) 37 degrees C; n = 8), moderate hypothermia (T(o) 28 degrees C; n = 8), or deep hypothermia (T(o) 20 degrees C; n = 8). Perioperative leukocyte activation, endotoxin release, and production of tumor necrosis factor-alpha (TNFalpha) and interleukin-10 (IL10) were examined with regard to post-operative organ damage, which was scored at histological examination of tissue probes of heart, lungs, liver, kidney, and ileum, taken 6 h after CPB. Total blood leukocyte count and TNFalpha plasma levels during CPB were significantly lower and IL10 levels were significantly higher in the moderate hypothermic group than in both other groups. Elastase activity, leukotriene B4-, and endotoxin levels were not affected by T(o) regimen. Moderate hypothermia was associated with the lowest histological organ damage score and normothermia with the highest. In all animals organ damage score for heart, lungs, and kidneys correlated significantly with TNFalpha levels at the end of CPB. Our data demonstrate a clear relationship between TNFalpha production during cardiac operations and post-operative multiple-organ damage. Moderate hypothermia, by stimulating IL10 synthesis and suppressing TNFalpha production during CPB, might provide organ protection. [less ▲]

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See detailPlant monitoring and fault detection - Synergy between data reconciliation and principal component analysis
Amand, Thierry; Heyen, Georges ULg; Kalitventzeff, Boris ULg

in Computers & Chemical Engineering (2001), 25(4-6), 501-507

Data reconciliation and principal component analysis are tno recognised statistical methods used for plant monitoring and fault detection. We propose to combine them for increased efficiency. Data ... [more ▼]

Data reconciliation and principal component analysis are tno recognised statistical methods used for plant monitoring and fault detection. We propose to combine them for increased efficiency. Data reconciliation is used in the first step of the determination of the projection matrix for principal component analysis (eigenvectors). principal component analysis can then be applied to raw process data for monitoring purpose. The combined use of these techniques aims at a better efficiency in fault detection. It relies mainly in a lower number of components to monitor. The method is applied to a modelled ammonia synthesis loop. (C) 2001 Elsevier Science Ltd. All rights reserved. [less ▲]

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See detailLiège. La cité des Princes-Evêques. Du Musée Curtius au Trésor de la Cathédrale
George, Philippe ULg; Demoulin, Bruno ULg; Kupper, Jean-Louis ULg et al

in Feuilllets de la Cathédrale de Liège (2001)

Exposition d'une soixantaine d'oeuvres d'art du Musée Curtius au Trésor de la Cathédrale de Liège dans une scénographie combinée, parcours d'art et d'histoire de la principauté de Liège(2001-2009)

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See detailSocial cues and verbal framing in risky choice
Wang, X. T.; Simons, F.; Brédart, Serge ULg

in Journal of Behavioral Decision Making (2001), 14

We examined how people use social and verbal cues of differing priorities in making social decisions. In Experiment 1, formally identical life-death choice problems were presented in different ... [more ▼]

We examined how people use social and verbal cues of differing priorities in making social decisions. In Experiment 1, formally identical life-death choice problems were presented in different hypothetical group contexts and were phrased in either a positive or negative frame. The risk-seeking choice became more dominant as the number of kin in an endangered group increased. Framing effects occurred only in a heterogeneous group context where the lives at risk were a mixture of kin and strangers. No framing effect was found when the same problem was presented in the context of a homogeneous group consisting of either all kin or all strangers. We viewed the framing effects to be a sign of indecisive risk preference due to the differential effects of a kinship cue and a stranger cue on choice. In Experiment 2, we presented the life-death problem in two artificial group contexts involving either 6 billion human lives or 6 billion extraterrestrial lives. A framing effect was found only in the human context. Two pre-conditions of framing effects appear to be social unfamiliarity of a decision problem and aspiration level of a decision maker. In Experiment 3, we analyzed the direction of the framing effect by balancing the framing. The direction of the framing effect depended on the baseline level of risk preference determined by a specific decision conte [less ▲]

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See detailComparative sequence analysis of the imprinted Dlk1-Gtl2 locus in three mammalian species reveals highly conserved genomic elements and refines comparison with the Igf2-H19 region.
Paulsen, M.; Takada, S.; Youngson, N. A. et al

in Genome Research (2001), 11(12), 2085-94

The Dlk1-Gtl2 domain on mouse chromosome 12 contains reciprocally imprinted genes with the potential to contribute to our understanding of common features involved in imprinting control. We have sequenced ... [more ▼]

The Dlk1-Gtl2 domain on mouse chromosome 12 contains reciprocally imprinted genes with the potential to contribute to our understanding of common features involved in imprinting control. We have sequenced this conserved region in the mouse and sheep and included the human sequence in a three species comparison. This analysis resulted in a precise conservation map and identification of highly conserved sequence elements, some of which we have shown previously to be differentially methylated in the mouse. Additionally, this analysis facilitated identification of a CpG-rich tandem repeat array located approximately 13-15 kb upstream of Gtl2. Furthermore, we have identified a third imprinted transcript that overlaps with the last Dlk1 exon in the mouse. This transcript lacks a conserved open reading frame and is probably generated by cleavage of extended Dlk1 transcripts. Because Dlk1 and Gtl2 share many of the imprinting properties of the well-characterized Igf2-H19 domain, it has been proposed that the two regions may be regulated in the same way. Comparative genomic examination of the two domains indicates that although there are similarities, other features are very different, including the location of conserved CTCF-binding sites, and the level of conservation at regulatory regions. [less ▲]

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See detailImmunisation against East Coast fever by the infection and treatment method: evaluation of the use of ice baths for field delivery and appraisal of an acid formulation of long-acting tetracycline.
Marcotty, T.; Billiouw, M.; Chaka, G. et al

in Veterinary Parasitology (2001), 99(3), 175-87

Immunisation by the infection and treatment method using the Katete strain is currently the most efficient prophylactic technique to control East Coast fever (ECF) in the endemic areas of the Eastern ... [more ▼]

Immunisation by the infection and treatment method using the Katete strain is currently the most efficient prophylactic technique to control East Coast fever (ECF) in the endemic areas of the Eastern Province of Zambia. The maintenance of the cold chain in liquid nitrogen up to the time of inoculation and the cost of the reference long-acting oxytetracycline (Terramycin LA, Pfizer) are the main drawbacks of the method. The work presented in this paper aims at reducing the cost of immunisation against ECF by using an ice bath for the field delivery and a cheaper long-acting oxytetracycline formulation as chemotherapeutic agent. In experimental conditions, the results from 40 calves immunised after various periods of storage on ice ranging from 4 to 32 h indicate that deferred immunisation performed with a stabilate kept on ice for up to 6h after thawing has an efficiency of 90%. Moreover, sporozoites kept on ice were still surviving 32 h after thawing. In a field trial, 91 calves were inoculated with a stabilate kept for 3.5-5.5 h after thawing and dilution whereas 86 calves were immunised using the standard method. Clinical and parasitological reactions to immunisation were monitored as well as the seroconversion. In the field trial, the deferred immunisation was more efficient than the standard method. The acid formulation of oxytetracycline that was tested was found as suitable as the reference alkaline formulation for the chemotherapeutic control of the Katete strain in ECF immunisation. One indoor trial was carried out on 10 animals and a field trial involved 93 calves. [less ▲]

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See detailEtude empirique des estimateurs des taux d'erreur en analyse discriminante
Piraux, François; Palm, Rodolphe ULg

in Revue de Statistique Appliquée (2001), XLIX(4), 71-85

Monte Carlo experiments are performed to compare ten parametric and six non parametric estimators of the three error rates (actual, expected and optimal error rate) in discriminant analysis. This ... [more ▼]

Monte Carlo experiments are performed to compare ten parametric and six non parametric estimators of the three error rates (actual, expected and optimal error rate) in discriminant analysis. This comparison is restricted to the context of two p-dimensional normal group conditional distributions with the same covariance matrix. The study shows that certain estimators are markedly superior and users should be warned against some estimators available in statistical softwares. [less ▲]

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See detailOrdovician cryptospores from the Oostduinkerke borehole, Brabant Massif, Belgium
Steemans, Philippe ULg

in Geobios (2001), 34(1), 3-12

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See detailAdditive and dominance genetic variance of fertility by method R and preconditioned conjugate gradient
Druet, Tom ULg; Solkner, J.; Groen, A. F. et al

in Journal of Dairy Science (2001), 84(4), 9871-98716

The objectives of this study were threefold: 1) estimation of additive and dominance genetic variances for fertility traits for Austrian Simmental and Brown Swiss dairy cattle; 2) use of method R and the ... [more ▼]

The objectives of this study were threefold: 1) estimation of additive and dominance genetic variances for fertility traits for Austrian Simmental and Brown Swiss dairy cattle; 2) use of method R and the preconditioned conjugate gradient compared to solving for method R by second-order Jacobi iteration; and 3) study of the impact of inclusion of parental subclass effects on solutions for other random effects. Dominance variances were modeled for the inseminated cow and ranged from 0.32 to 1.36% of total variance. These values were similar to values for additive effects, which were approximately 1% of total variance. Convergence was clearly improved with preconditioned conjugate gradient and number of extrapolations reduced. Variance for permanent environment under a model without dominance could be split into a new estimate of permanent environmental variance and parental subclass variance. Solutions for parental subclass dominance effects were approximately proportional to permanent environment effects, but highly dependent on the number of animals contributing dominance relationships, especially full-sibs and three-quarter-sibs. For animals with a lot of dominance information (full-sibs, three-quarter-sibs, cousins), permanent environment and parental subclass dominance effects were nearly independent. Changes in additive effects were negligible, probably because both variances for parental subclass dominance effects and additive genetic effects were very small compared with residual variance. [less ▲]

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See detailIntervalle entre vêlage chez la vache Borgou au Benin
Adamou-N'Diaye, M.; Ogodija, O. J.; Gbangboche, A. B. et al

in Annales de Médecine Vétérinaire (2001), 145(2), 130-136

This retrospective study has been carry out in the Monastery bovine exploitation of Kokoubou (department of Borgou in Benin). Data were collected and analysed from individual cow records of 1967 to 1989 ... [more ▼]

This retrospective study has been carry out in the Monastery bovine exploitation of Kokoubou (department of Borgou in Benin). Data were collected and analysed from individual cow records of 1967 to 1989. It concerned 150 Borgou cows and 838 calving intervals. The following parameters have been determined: monthly frequency of calving and calving interval. Monthly frequencies of calving are not regrouped in rainy season. Calving intervals have decreased with lactation numbers, while the season presents no effect. [less ▲]

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See detailTheoretical and experimental identification of a non-linear beam
Kerschen, Gaëtan ULg; Golinval, Jean-Claude ULg; Worden, K.

in Journal of Sound & Vibration (2001), 244

The identi"cation of the dynamic characteristics of linear systems is now widely used and interest in non-linear systems has increased. The objective of this paper is to demonstrate the performance of the ... [more ▼]

The identi"cation of the dynamic characteristics of linear systems is now widely used and interest in non-linear systems has increased. The objective of this paper is to demonstrate the performance of the restoring force surface method as far as the identi"cation of non-linear systems is concerned. The vibrations of a clamped beam are investigated for two di!erent kinds of non-linearity. Firstly, the beam shows a non-linear behaviour characterized by a piecewise linear sti!ness and secondly, the non-linearity comes from a bilinear sti!ness. Both numerical and experimental results are presented. (C) 2001 Academic Press [less ▲]

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See detailLa gestion des données dans le système SAS sous Windows v6.12
Fonton, N. H.; Claustriaux, Jean-Jacques ULg

in Notes de biométrie et d'informatique (2001), 1

The management of data is one of the major difficulties of the users in the SAS system. The note presents the procedures of data management after a brief summary on the organization and creation of data ... [more ▼]

The management of data is one of the major difficulties of the users in the SAS system. The note presents the procedures of data management after a brief summary on the organization and creation of data. Some procedures for statistics analysis are also presented. [less ▲]

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See detailAn overlay tree building control protocol
Mathy, Laurent ULg; Canonico, R.; Hutchison, D.

in Networked Group Communication (2001)

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See detailL'Ecole du dos
Crielaard, Jean-Michel ULg; Henrotin, Yves ULg; DEFAWEUX, Michel ULg et al

in Bulletin d'Education du Patient à sa Maladie (2001), 20

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See detailSensitivity analysis of longitudinal binary quality of life data with drop-out: an example using the EORTC QLQ-C30
Van Steen, Kristel ULg; Curran, D.; Molenberghs, G.

in Statistics in Medicine (2001), 20(24), 3901-20

Analysing quality of life data (QOL) may be complicated for several reasons. Quality of life data not only involves repeated measures but is also usually collected on ordered categorical responses. In ... [more ▼]

Analysing quality of life data (QOL) may be complicated for several reasons. Quality of life data not only involves repeated measures but is also usually collected on ordered categorical responses. In addition, it is evident that not all patients provide the same number of assessments, due to attrition caused by death or other medical reasons. In the recent statistical literature, increasing attention is given to methods which can handle non-continuous outcomes in the presence of missing data. The aim of this paper is to investigate the effect on statistical conclusions of applying different modelling techniques to QOL data generated from an EORTC phase III trial. Treatment effects and treatment differences are of major concern. First, a random-effects model is fitted, relating a binary longitudinal response (derived from the physical functioning scale of the QLQ-C30) to several covariates. In a second approach, marginal models are fitted, retaining the response variable and the mean structure used before. The fitted marginal models only differ with respect to the considered estimation procedure: generalized estimating equations (GEE); weighted generalized estimating equations (WGEE), and maximum likelihood (ML). [less ▲]

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See detailEffect of Ketoconazole 1% and 2% Shampoos on Severe Dandruff and Seborrhoeic Dermatitis: Clinical, Squamometric and Mycological Assessments
Pierard-Franchimont, Claudine ULg; Pierard, Gérald ULg; Arrese, J. E. et al

in Dermatology : International Journal for Clinical & Investigative Dermatology (2001), 202(2), 171-6

Ketoconazole (KET) is active to control dandruff and seborrhoeic dermatitis. Objective assessments comparing the 1% and 2% shampoo formulations are scant. This open, randomized parallel-group trial was ... [more ▼]

Ketoconazole (KET) is active to control dandruff and seborrhoeic dermatitis. Objective assessments comparing the 1% and 2% shampoo formulations are scant. This open, randomized parallel-group trial was carried out to differentiate the effectiveness of KET 1% and 2% in severe dandruff and seborrhoeic dermatitis. A total of 66 patients with severe dandruff or seborrhoeic dermatitis were randomized to each of the two groups. A 2-week run-in phase was followed by a 4-week treatment phase, in turn followed by a 4-week follow-up. The efficacy of treatments was evaluated by combining squamometry X, Malassezia spp. counts and clinical assessments. After 2 and 4 weeks of treatment, KET 2% was significantly superior over KET 1% (p < 0.001) for decreasing both in flakiness and Malassezia density from baseline. The same trend was observed in the mean change from baseline in the overall dandruff severity score. Only 6 mild adverse events were reported. During follow-up KET 2% showed a trend to fewer relapses than KET 1%. KET 2% had superior efficacy compared to KET 1% in the treatment of severe dandruff and scalp seborrhoeic dermatitis. Biometrological evaluations were correlated with the clinical improvements and therefore useful to incorporate in future dandruff studies. [less ▲]

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See detailShort-term variations of the partial pressure of CO2 in surface waters of the Galician upwelling system
Borges, Alberto ULg; Frankignoulle, Michel

in Progress in Oceanography (2001), 50(2-4), 283-302

The partial pressure of CO2 (pCO2) and dissolved oxygen saturation level (%O2) were monitored continuously during a cruise in August 1998, which sampled surface waters off the Galician coast. Data are ... [more ▼]

The partial pressure of CO2 (pCO2) and dissolved oxygen saturation level (%O2) were monitored continuously during a cruise in August 1998, which sampled surface waters off the Galician coast. Data are presented from two Lagrangian experiments carried out in an upwelling on the continental shelf and in the core of an offshore filament. The data show that daily variations in surface pCO2 and oxygen (%O2) were controlled by the diurnal cycle of primary production/respiration, temperature variations and air–sea exchange. Data obtained during various cross-shelf and cross-filament transects are also discussed and give an insight into the processes controlling large scale variations of pCO2 and %O2 in the Galician upwelling system. These data suggest that upwelling filaments are an important feature of the inorganic carbon cycle of upwelling systems. However more field data in the various eastern boundary current systems worldwide are needed. [less ▲]

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