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See detailThe contribution of social rank and attachment theory to depression in a non clinical sample of adolescents
Puissant, Sylvia Pinna; Gauthier, Jean-Marie ULg; Van Oirbeek, R. KUL

in Spanish Journal of Psychology (The) (2011)

This study explores the relative contribution of the overall quality of attachment to the mother, to the father and to peers (Inventory of Parent and Peer Attachment scales), the style of attachment ... [more ▼]

This study explores the relative contribution of the overall quality of attachment to the mother, to the father and to peers (Inventory of Parent and Peer Attachment scales), the style of attachment towards peers (Attachment Questionnaire for Children scale), the social rank variables (submissive behavior and social comparison), and sex and age variables in predicting the depression score (Center of Epidemiological Studies Depression Scale) on a non-psychiatric sample of 13-18 year old adolescents (n = 225). Results of our integrated model (adjusted R-Square of .50) show that attachment variables (overall quality of attachment to the father and to the mother), social rank variables (social comparison and submissive behavior), age and sex are important in predicting depressive symptoms during adolescence. Moreover, the attachment to peers variables (quality of attachment to peers, secure and ambivalent style of attachment) and sex are mediated by the social rank variables (social comparison and submissive behavior). [less ▲]

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See detailContribution of Spray Droplet Pinning Fragmentation to Canopy Retention
Boukhalfa, Hassina dite Hafida ULg; Massinon, Mathieu ULg; Belhamra, Mohamed et al

in Crop Protection (2014), 56

Drop behaviour during impact affects retention. The increase of adhesion is usually seen as the objective when applying crop protection products, while bouncing and shattering are seen as detrimental to ... [more ▼]

Drop behaviour during impact affects retention. The increase of adhesion is usually seen as the objective when applying crop protection products, while bouncing and shattering are seen as detrimental to spray retention. However, observation of drop impacts on barley (Hordeum vulgare L.) using high speed shadowgraphy shows that bouncing and fragmentation can occur in Cassie-Baxter as well as in Wenzel wetting regimes. In this last regime, a part of the drop may remain stuck on the surface, contributing to retention. Using simultaneous measurements of drop impacts with high speed imaging and of retention with fluorophotometry for spray mixtures on excised barley leaves using a Teejet 11003 nozzle at 0.2 MPa, it is observed that about 50% of the drops that fragmented in the Wenzel state remain on the horizontal leaf. Depending on the spray mixture, these impact outcomes accounted for 28 to 46% of retention, the higher contribution being correlated with bigger VMD (Volume Median Diameter). This contribution is not negligible and should be considered when modelling spray retention processes. [less ▲]

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See detailContribution of supercritical CO2 to the preparation of aliphatic polyesters and materials thereof
Stassin, Fabrice; Jérôme, Robert ULg

in Macromolecular Symposia (2004), 217

This paper is a short review of the most recent achievments of CERM in the synthesis of poly (ε-caprolactone) (PCL) and polylactides (PLA) in supercritical carbon dioxide (sc CO2) In addition to the ... [more ▼]

This paper is a short review of the most recent achievments of CERM in the synthesis of poly (ε-caprolactone) (PCL) and polylactides (PLA) in supercritical carbon dioxide (sc CO2) In addition to the rrtacromolecular engineering of these aliphatic polyesters, nanocomposites and PCL microspheres have been prepared with the assistance of this supercritical fluid. [less ▲]

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See detailContribution of the carbohydrate moiety to conformational stability of the carboxypeptidase Y high pressure study.
Dumoulin, Mireille ULg; Ueno, H.; Hayashi, R. et al

in European Journal of Biochemistry (1999), 262(2), 475-83

The process of pressure-induced denaturation of carboxypeptidase Y and the role of the carbohydrate moiety in its response to pressure and low temperature were investigated by measuring in situ the ... [more ▼]

The process of pressure-induced denaturation of carboxypeptidase Y and the role of the carbohydrate moiety in its response to pressure and low temperature were investigated by measuring in situ the catalytic activity and, the intrinsic and 8-anilino-1-naphthalene sulfonic acid binding fluorescences. Pressure-induced denaturation of carboxypeptidase Y is a process involving at least three transitions. Low pressures (below 150 MPa) induced slight conformational changes characterized by a slight decrease in the center of the spectral mass of intrinsic fluorescence, whereas no changes in 8-anilino-1-naphthalene sulfonic acid binding fluorescence were observed and 80% of the catalytic activity remained. Higher pressure (150-500 MPa) induced further conformational changes, characterized by a large decrease in the center of the spectral mass of intrinsic fluorescence, a large increase in the 8-anilino-1-naphthalene sulfonic acid binding fluorescence and the loss of all catalytic activity. Thus, this intermediate exhibited characteristics of molten globule-like state. A further increase, in pressure (above 550 MPa) induced transition from this first molten globule-like state to a second molten globule-like state. This two-stage denaturation process can be explained by assuming the existence of two independent structural domains in the carboxypeptidase molecule. A similar three-transition process was found for unglycosylated carboxypeptidase Y, but, the first two transitions clearly occurred at lower pressures than those for glycosylated carboxypeptidase Y. These findings indicate that the carbohydrate moiety protects carboxypeptidase Y against pressure-induced denaturation. The origin of the protective effects is discussed based on the known crystallographic structure of CPY. [less ▲]

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See detailContribution of the carbohydrate moiety to conformational stability of the carboxypeptidase Y high pressure study.
Dumoulin, Mireille ULg; Ueno, H.; Hayashi, R. et al

in European Journal of Biochemistry (1999), 262(2), 475-83

The process of pressure-induced denaturation of carboxypeptidase Y and the role of the carbohydrate moiety in its response to pressure and low temperature were investigated by measuring in situ the ... [more ▼]

The process of pressure-induced denaturation of carboxypeptidase Y and the role of the carbohydrate moiety in its response to pressure and low temperature were investigated by measuring in situ the catalytic activity and, the intrinsic and 8-anilino-1-naphthalene sulfonic acid binding fluorescences. Pressure-induced denaturation of carboxypeptidase Y is a process involving at least three transitions. Low pressures (below 150 MPa) induced slight conformational changes characterized by a slight decrease in the center of the spectral mass of intrinsic fluorescence, whereas no changes in 8-anilino-1-naphthalene sulfonic acid binding fluorescence were observed and 80% of the catalytic activity remained. Higher pressure (150-500 MPa) induced further conformational changes, characterized by a large decrease in the center of the spectral mass of intrinsic fluorescence, a large increase in the 8-anilino-1-naphthalene sulfonic acid binding fluorescence and the loss of all catalytic activity. Thus, this intermediate exhibited characteristics of molten globule-like state. A further increase, in pressure (above 550 MPa) induced transition from this first molten globule-like state to a second molten globule-like state. This two-stage denaturation process can be explained by assuming the existence of two independent structural domains in the carboxypeptidase molecule. A similar three-transition process was found for unglycosylated carboxypeptidase Y, but, the first two transitions clearly occurred at lower pressures than those for glycosylated carboxypeptidase Y. These findings indicate that the carbohydrate moiety protects carboxypeptidase Y against pressure-induced denaturation. The origin of the protective effects is discussed based on the known crystallographic structure of CPY. [less ▲]

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See detailContribution Of The Hydrophobicity Gradient Of An Amphipathic Peptide To Its Mode Of Association With Lipids
Perez-Mendez, O.; Vanloo, B.; Decout, A. et al

in European Journal of Biochemistry (1998), 256(3), 570-9

A class of peptides that associate with lipids, known as oblique-orientated peptides, was recently described [Brasseur R., Pillot, T., Lins, L., Vandekerckhove, J. & Rosseneu, M. (1997) Trends Biochem ... [more ▼]

A class of peptides that associate with lipids, known as oblique-orientated peptides, was recently described [Brasseur R., Pillot, T., Lins, L., Vandekerckhove, J. & Rosseneu, M. (1997) Trends Biochem. Sci. 22, 167-171]. Due to an asymmetric distribution of hydrophobic residues along the axis of the alpha-helix, such peptides adopt an oblique orientation which can destabilise membranes or lipid cores. Variants of these oblique peptides, designed to have an homogeneous distribution of hydrophobic and hydrophilic residues along the helical axis, are classified as regular amphipathic peptides. These peptides are expected to lie parallel to the polar/apolar interface with their hydrophobic residues directed towards the apolar and their hydrophilic residues towards the polar phase. An hydrophobic, oblique-orientated peptide was identified at residues 56-68 in the sequence of the lecithin-cholesterol acyltransferase (LCAT), enzyme. This peptide is predicted to penetrate a lipid bilayer at an angle of 40 degrees through its more hydrophobic C-terminal end and thereby induce the destabilisation of a membrane or a lipid core. The LCAT-(56-68) wild-type peptide was synthesised together with the LCAT-(56-68, 0 degrees) variant, in which the hydrophobicity gradient was abolished through residue permutations. In two other variants, designed to keep their oblique orientation, the W61 residue was shifted either towards the more hydrophilic N-terminal at residue 57, or to position 68 at the hydrophobic C-terminal end of the peptide. Peptide-induced vesicle fusion was demonstrated by fluorescence measurements using pyrene-labeled vesicles and by monitoring of vesicle size by gel filtration. The interaction between peptides and lipids was monitored by measurement of the intrinsic tryptophan fluorescence emission of the peptides. Fluorescence polarisation measurements, using diphenyl hexatriene, were carried out to follow changes in the lipid fluidity. The LCAT-(56-68) wild-type peptide and the two oblique variants, induced fusion of unilamellar dimyristoylglycerophosphocholine vesicles. Tryptophan fluorescence emission measurements showed a 12-14 nm blue shift upon addition of the wild-type peptide and of the W61-->68 variant to lipids, whereas the fluorescence of the W61-->57 variant did not change significantly. This observation supports the insertion of the more hydrophobic C-terminal residues into the lipid phase, as predicted by the theoretical calculations. In contrast, the 0 degrees variant peptide had no fusogenic activity, and it associated with lipids to form small discoidal lipid/peptide complexes. The phospholipid transition temperature was decreased after addition of the wild-type, the W61-->68 and W61-->57 fusogenic peptides, whereas the opposite effect was observed with the 0 degrees variant. The behaviour of the wild-type and variant LCAT-(56-68) peptides stresses the contribution of the hydrophobicity gradient along the axis of an amphipathic peptide to the mode of association of this peptide with lipids. This parameter consequently influences the structural modifications occurring to lipids upon association with amphipathic peptides. [less ▲]

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See detailContribution Of The Hydrophobicity Gradient To The Secondary Structure And Activity Of Fusogenic Peptides
Decout, A.; Labeur, C.; Vanloo, B. et al

in Molecular Membrane Biology (1999), 16(3), 237-46

Fusogenic peptides belong to a class of helical amphipathic peptides characterized by a hydrophobicity gradient along the long helical axis. According to the prevailing theory regarding the mechanism of ... [more ▼]

Fusogenic peptides belong to a class of helical amphipathic peptides characterized by a hydrophobicity gradient along the long helical axis. According to the prevailing theory regarding the mechanism of action of fusogenic peptides, this hydrophobicity gradient causes the tilted insertion of the peptides in membranes, thus destabilizing the lipid core and, thereby, enhancing membrane fusion. To assess the role of the hydrophobicity gradient upon the fusogenic activity, two of these fusogenic peptides and several variants were synthesized. The LCAT-(57-70) peptide, which is part of the sequence of the lipolytic enzyme lecithin cholesterol acyltransferase, forms stable beta-sheets in lipids, while the apolipoprotein A-II (53-70) peptide remains predominantly helical in membranes. The variant peptides were designed through amino acid permutations, to be either parallel, perpendicular, or to retain an oblique orientation relative to the lipid-water interface. Peptide-induced vesicle fusion was monitored by lipid-mixing experiments, using fluorescent probes, the extent of peptide-lipid association, the conformation of lipid-associated peptides and their orientation in lipids, were studied by Fourier Transformed Infrared Spectroscopy. A comparison of the properties of the wild-type and variant peptides shows that the hydrophobicity gradient, which determines the orientation of helical peptides in lipids and their fusogenic activity, further influences the secondary structure and lipid binding capacity of these peptides. [less ▲]

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See detailCONTRIBUTION OF THE NEW TECHNOLOGIES TO THE REHABILITATION OF THE OLD FALLERS : A PILOT STUDY
ELBOUZ, LEILA; GILLAIN, Sophie ULg; BENDAVID, D et al

in Gériatrie et Psychologie Neuropsychiatrie du Vieillissement (2012), 10(4), 383-390

Purpose of the study: to verify the interest of vibrosphère™ in the rehabilitation of geriatric fallers Material and method: 24 persons aged 85.5 hospitalized in geriatric wards for a fall during the last ... [more ▼]

Purpose of the study: to verify the interest of vibrosphère™ in the rehabilitation of geriatric fallers Material and method: 24 persons aged 85.5 hospitalized in geriatric wards for a fall during the last 6 months are divided in 2 groups. The group one has performed a classical revalidation and the group 2 a rehabilitation with the technics of vibrosphère™, both during 9 days. The assessment is realized on Day 0 and day 10. It consists in a walking test with Locometrix, a postural assessment a time get up and go and the fall efficacity scale. A control group of 20 non faller subjects aged 79,9 is constituted. Results: in the second population a gain (p< 0.05) is obtained for speed of gait, and also a tendancy in a better frequency, length, symmetry and regularity of step. Postural status is better at the end of the 9 days in the grouped using vibrosphère™. The 2 ways of rehabilitation have similar effects on the gait and balance parameters. Conclusion: our study confirms efficiency of rehabilitation program for 9 days which is rather short. The improvements show that vibrosphère™ is a well adapted tool to revalidate geriatric fallers. Its effect on balance should explain the benefit observed in the gait parameters. This technique seems to be complementary with classical rehabilitation in old geriatric hospitalized patients. [less ▲]

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See detailContribution of the quantitative interpretation of gamma-ray logs to the study of limestone exploitation, a case-study at Maizeret, Belgium
Halleux, Isabelle ULg

in Geoexploration (1999), 24(6), 461-470

Economic considerations constrain quarrymen in Wallonia to consider more profit-earning exploitation of limestone deposits and (or) to diversify their products. Gamma-ray logs contain information about ... [more ▼]

Economic considerations constrain quarrymen in Wallonia to consider more profit-earning exploitation of limestone deposits and (or) to diversify their products. Gamma-ray logs contain information about the geology, structure and quality of deposits. Quantitative interpretation of the logs is necessary in order to provide a reasonably good image of reality. The method proposed here consists in removing the effects of different parameters influencing the measurements (analog ratemeter, statistical noise, etc.) and in deconvolving the data in the frequency domain by the analytical impulse response function of the system. An example demonstrates that mathematical processing increases the lithologic and stratigraphic definition of the logs (bed boundaries, bed thicknesses) and offers a satisfactory characterization of the rocks along boreholes. Some of the quarrymen's questions can be answered from this analysis. [less ▲]

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See detailContribution of tobacco smoking to dioxin accumulation: opposite effects according to gender
Fierens, Sébastian; Eppe, Gauthier ULg; Focant, Jean-François ULg et al

in Organohalogen Compounds (2004), 66

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See detailContribution of tree-ring analysis to the study of droughts in north-western France (XIX-XXth century)
Planchon, Olivier; Dubreuil, Vincent; Bernard, Vincent et al

in Climate of the Past Discussions (2008), 4

A tree-ring analysis based on oak samples in the North-West of France showed the effects of droughts periods on the growth index, during the late XIXth and XXth century. Four types of droughts were ... [more ▼]

A tree-ring analysis based on oak samples in the North-West of France showed the effects of droughts periods on the growth index, during the late XIXth and XXth century. Four types of droughts were identified using the results of the tree-ring analysis and the available climate data. The “type 1” was subjected to a continuous and intense drought during all the vegetative period (spring and summer), the “type 2” was subjected to a summer drought succeeding no precipitation deficit in spring, the “type 3” was subjected to a remarkable winter drought and during the years of the “type 4”, precipitation deficits were recorded for several but not successive months, over an heterogeneous spatial distribution. The long, intense and countinuous droughts clearly showed a spatial structuring effect on the growth index, especially when the two successive vegetative seasons (spring and summer) recorded strong precipitation deficits combined with shrivellings. These extreme cases involved the lowest growth index over most of the studied area, with some variations due to the altitude and exposure effects on the local-scale spatial distribution of the hydrological stress. The hydrological balance for the station of Rennes (Brittany) confirmed these results in accordance with the intensity and/or duration of drought periods: the most intense droughts of the “type 1“ were especially pointed out. A climatic interpretation of growth index data and maps could so be possible over northwestern France with an application to the medieval times and perhaps to other periods, but the cause of the different drought patterns must be more precisely studied during the contemporary period (late XIXth century and all the XXth century). [less ▲]

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See detailThe contribution of uncoupling protein and ATP synthase to state 3 respiration in Acanthamoeba castellanii mitochondria.
Jarmuszkiewicz, W.; Czarna, M.; Sluse-Goffart, C. et al

in Acta Biochimica Polonica. Polish. (2004), 51

Mitochondria of the amoeba Acanthamoeba castellanii possess a free fatty acid-activated uncoupling protein (AcUCP) that mediates proton re-uptake driven by the mitochondrial proton electrochemical ... [more ▼]

Mitochondria of the amoeba Acanthamoeba castellanii possess a free fatty acid-activated uncoupling protein (AcUCP) that mediates proton re-uptake driven by the mitochondrial proton electrochemical gradient. We show that AcUCP activity diverts energy from ATP synthesis during state 3 mitochondrial respiration in a fatty acid-dependent way. The efficiency of AcUCP in mitochondrial uncoupling increases when the state 3 respiratory rate decreases as the AcUCP contribution is constant at a given linoleic acid concentration while the ATP synthase contribution decreases with respiratory rate. Respiration sustained by this energy-dissipating process remains constant at a given linoleic acid concentration until more than 60% inhibition of state 3 respiration by n-butyl malonate is achieved. The present study supports the validity of the ADP/O method to determine the actual contributions of AcUCP (activated with various linoleic acid concentrations) and ATP synthase in state 3 respiration of A.castellanii mitochondria fully depleted of free fatty acid-activated and describes how the two contributions vary when the rate of succinate dehydrogenase is decreased by succinate uptake limitation [less ▲]

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See detailContribution of unsymmetrical difunctional initiators/monomers to the macromolecular engineering
Jérôme, Robert ULg

in Macromolecular Symposia (2002), 177

The emerging technologies (e.g. in optics, microelectronics, medicine...) require the availability of synthetic polymers with continuously more sophisticated properties and performances. The best way for ... [more ▼]

The emerging technologies (e.g. in optics, microelectronics, medicine...) require the availability of synthetic polymers with continuously more sophisticated properties and performances. The best way for the polymer chemist to face this challenge is to tailor the molecular structure of the chains. Nowadays, the progress in the living/controlled polymerization mechanisms is such that the so-called macromolecular engineering is a vivid reality. [less ▲]

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See detailContribution of violaxanthin, neoxanthin, phytoene and phytofluene to total carotenoid intake: Assessment in Luxembourg
Biehler, E; Hoffmann, L; Krause, E et al

in Journal of Food Composition and Analysis (2012), 25

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See detailContribution of whole-body (18)FDG PET imaging in the management of cervical cancer
Belhocine, T.; Thille, Alain ULg; Fridman, Viviana ULg et al

in Gynecologic Oncology (2002), 87(1), 90-97

OBJECTIVE: The objective of this study was to assess the contribution of [(18)F]fluoro-2-deoxy-D-glucose positron emission tomography ((18)FDG PET) imaging in the management of cervical cancer. METHODS ... [more ▼]

OBJECTIVE: The objective of this study was to assess the contribution of [(18)F]fluoro-2-deoxy-D-glucose positron emission tomography ((18)FDG PET) imaging in the management of cervical cancer. METHODS: Fully corrected whole-body PET was performed in 60 patients (pts) with proven cervical cancer. In pretreatment staging, 22 pts underwent PET in addition to routine protocol including International Federation of Obstetrics and Gynecology (FIGO) staging and pelvic magnetic resonance imaging (MRI). Eighteen of them had pelvic lymphadenectomy. After treatment, PET was performed in 38 pts routinely followed up by clinical and radiological examinations. Results of PET and routine protocols were compared to final diagnoses, including histological findings in 31 pts and clinical outcomes in the other cases. Median follow-up time was 12 +/- 7.3 months. RESULTS: In all but 2 patients (FIGO stage IA), both PET and MRI detected the primary tumor. In 6 pts, MRI alone noted loco-regional tumor spread but PET localized 9 unsuspected extrapelvic nodal sites (6 para-aortic, 2 mediastinal, and 1 supra-clavicular). However, PET missed 8 microscopic pelvic nodal metastases. In 18% of the patients, PET staging significantly influenced the treatment choices. In follow-up, PET accurately diagnosed a recurrent disease in 13 pts with falsely negative or equivocal conventional imaging (CI). Ten patients with a negative PET were still in complete remission after a minimal follow-up time of 12 months. Overall, the agreement of PET with final diagnosis was significantly better than that of routine protocol (P < 0.05). CONCLUSIONS: Whole-body (18)FDG PET appears useful in the management of cervical cancer, in particular for staging extrapelvic metastases or optimally detecting a recurrence. MRI is better indicated for evaluating the loco-regional status of the disease. [less ▲]

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