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See detailCycles of humid-dry climate conditions around the P/E boundary: New stable isotope data from terrestrial organic matter in Vasterival section (NW France)
Storme, Jean-Yves ULg; Dupuis, C.; Schnyder, J. et al

in Terra Nova (2012), 24(2), 114-122

The Palaeocene/Eocene boundary (P/EB) and the Palaeocene-Eocene Thermal Maximum (55.8Ma) are defined stratigraphically based on carbon isotope ratios of various materials. Here, the position of the P/EB ... [more ▼]

The Palaeocene/Eocene boundary (P/EB) and the Palaeocene-Eocene Thermal Maximum (55.8Ma) are defined stratigraphically based on carbon isotope ratios of various materials. Here, the position of the P/EB is refined in the terrestrial-lacustrine and swampy Vasterival section (Upper Normandy coast, France) by using carbon isotopes measured on dispersed organic matter (δ 13C org). Moreover, nitrogen isotopes on dispersed organic matter (δ 15N org) are, for the first time in the Palaeogene record, associated with carbon isotope and lithological data to constrain palaeoclimatic and environmental changes around the P/EB in a terrestrial environment. Humid-dry fluctuations before and during this key interval in Earth history are suggested. © 2012 Blackwell Publishing Ltd. [less ▲]

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See detailCyclic and oligo-carbonates by organocatalytic coupling of CO2 with epoxides or oxetanes
Alves, Margot ULg; Grignard, Bruno ULg; Boyaval, Amélie ULg et al

Conference (2016, April 20)

Valorising CO2 as a renewable C1 feedstock for producing added value building blocks is the scope of many academic and industrial researches. Carbon dioxide is a thermodynamically and kinetically stable ... [more ▼]

Valorising CO2 as a renewable C1 feedstock for producing added value building blocks is the scope of many academic and industrial researches. Carbon dioxide is a thermodynamically and kinetically stable molecule that can be converted into five and six membered cyclic carbonates by coupling with epoxides or oxetanes, respectively, using appropriate catalysts. Although transition metal catalysts are efficient under atmospheric pressure and ambient temperature, most of them are poorly selective, sensitive to hydrolysis and/or oxidation and/or toxic whereas less/non-toxic and eco-friendly organocatalysts such as ionic liquids and halide salts are generally only efficient at very high temperature and pressure favouring their thermal degradation. To overcome these limitations, we developed a new highly efficient bicomponent homogeneous organocatalyst composed of an ammonium salt as the catalyst and fluorinated single or double hydrogen bond donor activators. Through online FTIR kinetic studies, we demonstrated that this new organocatalyst showed unexpected catalytic activity for the fast and selective addition of CO2 onto epoxides under solvent-free and mild experimental conditions. The use of this dual catalyst was then extended to the coupling of CO2 with less reactive oxetanes to produce hydroxyl telechelic oligocarbonates. In the first part of this talk, based on kinetics of reactions followed by online FTIR under pressure, we will describe the reaction conditions required for the organocatalytic coupling of CO2 with epoxides and oxetanes. In the second part, the mechanism of the reaction will be approached and discussed based on DFT calculations. Finally, we will compare and discuss the efficiency of various organocatalytic systems for this type of reaction. [less ▲]

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See detailCyclic appearance of left ventricular outflow tract dynamic obstruction during mechanical ventilation: evidence for a preload dependent phenomenon.
Canivet, Jean-Luc ULg; Lancellotti, Patrizio ULg; Radermecker, Marc ULg et al

in Journal of Intensive Care Medicine (2008), 23(4), 281-4

The cyclic appearance of dynamic left ventricular outflow tract obstruction during mechanical ventilation, according to the phasic changes in preload, is described in this article. Hemodialysis-induced ... [more ▼]

The cyclic appearance of dynamic left ventricular outflow tract obstruction during mechanical ventilation, according to the phasic changes in preload, is described in this article. Hemodialysis-induced fluid removal resulted in preload dependence as evidenced by the pulse pressure variation in a 56-year-old critically ill patient. The clinical picture was suggestive of myocardial failure. Transthoracic echocardiography disclosed dynamic left ventricular outflow tract obstruction associated with systolic anterior motion of the mitral valve. Progressive fluid restitution resulted in a parallel decrease in both the degree of dynamic obstruction and pulse pressure variation. During fluid loading, dynamic obstruction disappeared at first during the inspiratory phase of intermittent positive pressure ventilation corresponding to the phasic increase in left ventricular preload. Further fluid loading resulted in the disappearance of dynamic obstruction during both inspiratory and expiratory phase of intermittent positive pressure ventilation. This is the first reported case clearly relating left ventricular outflow tract dynamic obstruction to preload dependence during mechanical ventilation in a critically ill patient without predisposing anatomical factor. [less ▲]

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See detailCyclic behaviour of cohesionless soils under seismic loading
Cerfontaine, Benjamin ULg

Diverse speeche and writing (2012)

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See detailThe cyclic behaviour of sand, from the Prevost model to offshore geotechnics
Cerfontaine, Benjamin ULg

Doctoral thesis (2014)

The main objective of this thesis is the studying of the cyclic behaviour of dense sand. Its centre of gravity is the implementation of a convenient constitutive law in the finite element code LAGAMINE ... [more ▼]

The main objective of this thesis is the studying of the cyclic behaviour of dense sand. Its centre of gravity is the implementation of a convenient constitutive law in the finite element code LAGAMINE. The first step consists in summarising the salient features of the cyclic behaviour of sand observed in laboratory tests. Undrained monotonic and cyclic experiments are addressed. The phase transformation line is a key parameter in the description of its behaviour. The plasticity effects in both loading and unloading, the progressive pore pressure accumulation coupled with the degradation of the stiffness of the soil are of uttermost importance in the cyclic behaviour. The Prevost model is adopted for its conceptual simplicity and its physically related parameters. The basic equations of the model are described and its variants are illustrated. Calibration of the required parameters is carried out by means of simplified routines implemented in Matlab. A unique set of parameters is determined for each soil at a given relative density. Monotonic experiments are well reproduced. The model also replicates satisfactorily the trend of cyclic experiments. An implicit scheme is embraced in order to implement the model in the finite element code LAGAMINE. The implicit Prager translation rule is adopted for that purpose. It is ensured the discrete formulation reproduces exactly the analytical model. Accuracy, efficiency and robustness of the model are addressed throughout triaxial and multi-axial numerical examples. A hydro-mechanical interface finite element is developed. It consists in a three-node 1D isoparametric element. It is able to reproduce fluid flows across and along the interface. The unsticking of both walls of the interface is coupled with a suction effect due to the filling of the vacuum created. The behaviour of the element is illustrated by simple 1D examples of transient consolidation of a soil column. A final application consists in the modelling of a suction caisson, part of a tripod structure for wind turbines. An axisymmetric representation of this foundation is carried out. It is assumed embedded into dense Lund sand described by the Prevost model. Monotonic and cyclic simulations are performed in both drained and partially drained conditions. The salient features of the resistance of such foundations are highlighted. Their partially drained behaviour strongly increases their transient resistance. A storm including an extreme event is employed to simulate a cyclic loading. A pseudo-random short signal and its sinusoidal equivalent representation finally lead to an identical vertical settlement. This is confirmed by a long duration storm. Finally, a cyclic diagram summarising the final settlement attained for combinations of average and cyclic vertical loads is elaborated. Keywords [less ▲]

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See detailCyclic catamenial dermatoses.
Hermanns-Lê, Trinh ULg; Hermanns, Jean François; Lesuisse, Marianne et al

in BioMed Research International (2013), 2013

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See detailCyclic esterketone compounds and processes for the synthesis and use thereof
Wautier, Henri; Laterre, Jean-Pierre; Lecomte, Philippe ULg et al

Patent (2001)

Cyclic esterketone compounds, and in particular, 2-oxepane-1,5-dione, which are useful as a monomer for the production of polymers, and in particular for the production of poly(2-oxepane-1,5-dione ... [more ▼]

Cyclic esterketone compounds, and in particular, 2-oxepane-1,5-dione, which are useful as a monomer for the production of polymers, and in particular for the production of poly(2-oxepane-1,5-dione). Processes are also disclosed for both the synthesis of this new compound and for the use (polymerization) thereof for the preparation of poly(2-oxepane-1,5-dione). The poly(2-oxepane-1,5-dione) polymers and copolymers which are obtained by use of the polymerization processes with the monomer compounds are also disclosed. [less ▲]

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See detailCyclic esterketone compounds, processes for the synthesis thereof
Wautier, Henri; Latere, Jean-Pierre; Lecomte, Philippe ULg et al

Patent (2000)

Cyclic esterketone compounds, and in particular, 2-oxepane-1,5-dione, which are useful as a monomer for the production of polymers, and in particular for the production of poly(2-oxepane-1,5-dione ... [more ▼]

Cyclic esterketone compounds, and in particular, 2-oxepane-1,5-dione, which are useful as a monomer for the production of polymers, and in particular for the production of poly(2-oxepane-1,5-dione). Processes are also disclosed for both the synthesis of this new compound and for the use (polymerization) thereof for the preparation of poly(2-oxepane-1,5-dione). The poly(2-oxepane-1,5-dione) polymers and copolymers which are obtained by use of the polymerization processes with the monomer compounds are also disclosed. [less ▲]

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See detailCyclic esterketone compounds, processes for the synthesis thereof and process for the preparation of poly (esterketone) polymers
Wautier, Henri; Latere, Jean-Pierre; Lecomte, Philippe ULg et al

Patent (2002)

Unsubstituted oxepane-diones useful as monomers for the production of polymers, process for the synthesis thereof by oxidation of unsubstituted cyclohexanediones, process for the preparation of ... [more ▼]

Unsubstituted oxepane-diones useful as monomers for the production of polymers, process for the synthesis thereof by oxidation of unsubstituted cyclohexanediones, process for the preparation of polyesterketone polymers by polymerization of cyclic esterketones and polyesterketone polymers so obtained. [less ▲]

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See detailCyclic esterketone compounds, processes for the synthesis thereof and process for the preparation of poly (esterketone) polymers
Wautier, Henri; Latere, Jean-Pierre; Lecomte, Philippe ULg et al

Patent (2001)

PROBLEM TO BE SOLVED: To provide a monomer compound, which is improved to be useful as the novel monomer for forming a poly(ester ketone)polymer by polymerization, and can be directly synthesized in high ... [more ▼]

PROBLEM TO BE SOLVED: To provide a monomer compound, which is improved to be useful as the novel monomer for forming a poly(ester ketone)polymer by polymerization, and can be directly synthesized in high yield in a one-stage process from the stock material. SOLUTION: This compound is a novel cyclic ester compound, in particular 2-oxepane-1,5-dione (KCL), synthesized in one-stage process involving oxidation of the stock material (cyclic diketone, e.g. 1,4-cyclohexane-dione) and useful for simply and easily producing a poly(ester ketone)polymer, in particular poly(2- oxepane-1,5-dione) (PKCL) in high yield. [less ▲]

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See detailCyclic esterketone compounds, processes for the synthesis thereof and process for the preparation of poly(esterketone)polymers
Wautier, Henri; Latere, Jean-Pierre; Lecomte, Philippe ULg et al

Patent (2000)

Unsubstituted oxepane-diones useful as monomers for the production of polymers, process for the synthesis thereof by oxidation of unsubstituted cyclohexanediones, process for the preparation of ... [more ▼]

Unsubstituted oxepane-diones useful as monomers for the production of polymers, process for the synthesis thereof by oxidation of unsubstituted cyclohexanediones, process for the preparation of polyesterketone polymers by polymerisation of cyclic esterketones and polyesterketone polymers so obtained. [less ▲]

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See detailCyclic lipopeptide profile of the plant-beneficial endophytic bacterium Bacillus subtilis HC8
Malfanova, N.; Franzil, Laurent ULg; Lugtenberg, B. et al

in Archives of Microbiology (2012)

In a previous study (Malfanova et al. in Microbial Biotech 4:523-532, 2011), we described the isolation and partial characterization of the biocontrol endophytic bacterium B. subtilis HC8. Using thin ... [more ▼]

In a previous study (Malfanova et al. in Microbial Biotech 4:523-532, 2011), we described the isolation and partial characterization of the biocontrol endophytic bacterium B. subtilis HC8. Using thin-layer chromatography, we have detected several bioactive antifungal compounds in the methanolic extract from the acid-precipitated supernatant of HC8. In the present study, we have further analyzed this methanolic extract using liquid chromatography-mass spectrometry. Based on the comparison of retention times and molecular masses with those of known antifungal compounds, we identified three families of lipopeptide antibiotics. These include four iturins A having fatty acyl chain lengths of C14 to C17, eight fengycins A (from C14 to C18 and from C15 to C17 containing a double bond in the acyl chain), four fengycins B (C15 to C18), and five surfactins (C12 to C16). Evaluation of the antifungal activity of the isolated lipopeptides showed that fengycins are the most active ones. To our knowledge, this is the first report of an endophytic Bacillus subtilis producing all three major families of lipopeptide antibiotics containing a very heterogeneous mixture of homologues. The questions remain open which of these lipopeptides (1) are being produced during interaction with the plant and (2) are contributing to the biocontrol activity of HC8. © 2012 The Author(s). [less ▲]

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See detailCyclic lipopeptides from Bacillus subtilis activate distinct patterns of defence responses in grapevine.
Farace, Giovanni; Fernandez, Olivier; Jacquens, Lucile et al

in Molecular plant pathology (2014)

Non-self-recognition of microorganisms partly relies on the perception of microbe-associated molecular patterns (MAMPs) and leads to the activation of an innate immune response. Bacillus subtilis produces ... [more ▼]

Non-self-recognition of microorganisms partly relies on the perception of microbe-associated molecular patterns (MAMPs) and leads to the activation of an innate immune response. Bacillus subtilis produces three main families of cyclic lipopeptides (LPs), namely surfactins, iturins and fengycins. Although LPs are involved in induced systemic resistance (ISR) activation, little is known about defence responses induced by these molecules and their involvement in local resistance to fungi. Here, we showed that purified surfactin, mycosubtilin (iturin family) and plipastatin (fengycin family) are perceived by grapevine plant cells. Although surfactin and mycosubtilin stimulated grapevine innate immune responses, they differentially activated early signalling pathways and defence gene expression. By contrast, plipastatin perception by grapevine cells only resulted in early signalling activation. Gene expression analysis suggested that mycosubtilin activated salicylic acid (SA) and jasmonic acid (JA) signalling pathways, whereas surfactin mainly induced an SA-regulated response. Although mycosubtilin and plipastatin displayed direct antifungal activity, only surfactin and mycosubtilin treatments resulted in a local long-lasting enhanced tolerance to the necrotrophic fungus Botrytis cinerea in grapevine leaves. Moreover, challenge with specific strains overproducing surfactin and mycosubtilin led to a slightly enhanced stimulation of the defence response compared with the LP-non-producing strain of B. subtilis. Altogether, our results provide the first comprehensive view of the involvement of LPs from B. subtilis in grapevine plant defence and local resistance against the necrotrophic pathogen Bo. cinerea. Moreover, this work is the first to highlight the ability of mycosubtilin to trigger an immune response in plants. [less ▲]

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See detailCyclic RR Telescopii
Heck, Andre; Manfroid, Jean ULg

Article for general public (1984)

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See detailCyclic variations in incubation conditions induce adaptive responses to later heat exposure in chickens: a review
Loyau, T.; Bedrani, L.; Berri, C. et al

in Animal (2015), 9

Selection programs have enabled broiler chickens to gain muscle mass without similar enlargement of the cardiovascular and respiratory systems that are essential for thermoregulatory efficiency. Meat-type ... [more ▼]

Selection programs have enabled broiler chickens to gain muscle mass without similar enlargement of the cardiovascular and respiratory systems that are essential for thermoregulatory efficiency. Meat-type chickens cope with high ambient temperature by reducing feed intake and growth during chronic and moderate heat exposure. In case of acute heat exposure, a dramatic increase in morbidity and mortality can occur. In order to alleviate heat stress in the long term, research has recently focused on early thermal manipulation. Aimed at stimulation of long-term thermotolerance, the thermal manipulation of embryos is a method based on fine tuning of incubation conditions, taking into account the level and duration of increases in temperature and relative humidity during a critical period of embryogenesis. The consequences of thermal manipulation on the performance and meat quality of broiler chickens have been explored to ensure the potential application of this strategy. The physiological basis of the method is the induction of epigenetic and metabolic mechanisms that control body temperature in the long term. Early thermal manipulation can enhance poultry resistance to environmental changes without much effect on growth performance. This review presents the main strategies of early heat exposure and the physiological concepts on which these methods were based. The cellular mechanisms potentially underlying the adaptive response are discussed as well as the potential interest of thermal manipulation of embryos for poultry production. © The Animal Consortium 2014. [less ▲]

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See detailCyclical Cushing's disease : a case report.
Velkeniers, B.; Beckers, Albert ULg; Stevenaert, Achille ULg et al

in Pathology - Research & Practice (1991), 187(5), 603-607

A 41-year-old man with clinical Cushing's syndrome and intermittent central ACTH hypersecretion for a period of 9 1/2 years follow-up is described. Episodes of biochemical and clinical remission ... [more ▼]

A 41-year-old man with clinical Cushing's syndrome and intermittent central ACTH hypersecretion for a period of 9 1/2 years follow-up is described. Episodes of biochemical and clinical remission alternated with periods of florid Cushing's disease, characterized by circadian hyperpulsatile ACTH and cortisol secretion. Responses to metyrapone and inhibition of ACTH and cortisol hypersecretion after high dose dexamethasone during active phases of the disease favored a central origin of ACTH hypersecretion, confirmed by simultaneous bilateral venous sampling of the sinus petrosus inferior. Prolonged clinical remission followed near total anterior hypophysectomy. However, on anatomopathological examination of the pituitary neither corticotroph cell hyperplasia nor a microadenoma could be documented. The possibility of a functional ACTH hypersecretion is discussed. [less ▲]

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See detailCyclical Cushing's disease : a case report.
Velkeniers, B.; Beckers, Albert ULg; Stevenaert, Achille ULg et al

in Société Belge de Médecine Interne (1990)

Detailed reference viewed: 5 (0 ULg)