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See detail2-, 3- and 4-substituted pyrido[4,3-e]-1,2,4-thiadiazine 1,1-dioxides as ATP-sensitive potassium channel openers
De Tullio, Pascal ULg; Pirotte, Bernard ULg; Ouedraogo, R. et al

in Journal de Pharmacie de Belgique (1996), 51

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See detailThe 2-3 minutes periodicity in the polar aurora and the magnetosphere of Jupiter
Bonfond, Bertrand ULg; Grodent, Denis ULg; Gérard, Jean-Claude ULg et al

Poster (2013, December 10)

The main aurora at Jupiter is related to the middle magnetosphere and the corotation breakdown of the magnetospheric plasma. On the other hand, the polar regions either magnetically map to the outer ... [more ▼]

The main aurora at Jupiter is related to the middle magnetosphere and the corotation breakdown of the magnetospheric plasma. On the other hand, the polar regions either magnetically map to the outer magnetosphere or correspond to field lines open to the interplanetary medium and most of the auroral emissions from this region are still poorly understood. Among these polar auroral emissions are the flares, dramatic brightenings of several million square kilometers over a couple of minutes. Two previously reported observations of the southern hemisphere showed that these flares can be quasi-periodic with a re-occurrence time of 2-3 minutes. Here we report results from the Hubble Space Telescope campaign carried out in 2012-2013 with the STIS FUV instrument in time-tag mode (PI: D. Grodent). This campaign consisted in alternating observations of the two hemispheres. Based on the analysis of this dataset, we confirm that these quasi-periodic flares are ubiquitous and occur in both hemispheres. Moreover, in at least one case, these flares appear to occur in phase in both hemispheres. We compare the characteristics of these flares with those of the relativistic electron bursts observed by the Ulysses spacecraft with the HET instrument. We find that 2-3 minutes quasi-periodic burst are much more frequent than previously reported and that they magnetically map to the same auroral area as the flares. We conclude that these two phenomena are most probably related and arise from a common origin. [less ▲]

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See detail2-abelian complexity of the Thue-Morse sequence
Rigo, Michel ULg; Vandomme, Elise ULg

Scientific conference (2012, December 14)

Let k be an integer. Two words u and v of the same length are k-abelian equivalent, if they have the same prefix (resp. suffix) of length k-1 and if, for all words x of length k, the numbers of ... [more ▼]

Let k be an integer. Two words u and v of the same length are k-abelian equivalent, if they have the same prefix (resp. suffix) of length k-1 and if, for all words x of length k, the numbers of occurrences of x in u and v are the same. This notion has received some recent interest, see the works of Karhumäki et al. The k-abelian complexity of an infinite word x maps an integer n to the number of k-abelian classes partitioning the set of factors of length n occurring in x. The Thue-Morse word is a well-known and extensively studied 2-automatic sequence. It is trivially abelian periodic and its (1)-abelian complexity takes only two values. The aim of this talk is to explain how to compute the 2-abelian complexity a(n) of the Thue-Morse word, showing in particular that it is unbounded. We conjecture that a(n) is 2-regular in the sense of Allouche and Shallit. This question can be related to a recent work of Madill and Rampersad where the (1)-abelian complexity of the paper folding word is shown to be 2-regular. We will also explain why the usual logical framework introduced by Büchi and popularized by Bruyère (indeed, automatic sequences can be characterized in an extension of the Presburger arithmetic) and the recent work of Charlier et al. about "automatic theorem-proving" of properties of automatic sequences cannot be applied to these questions related to abelian complexity. [less ▲]

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See detail2-Alkyl-3-alkylamino-2H-benzo- and pyridothiadiazine 1,1-dioxides: Ca++ channel blockers rather than K+ATP channel openers?
De Tullio, Pascal ULg; Becker, B.; Ouedraogo, R. et al

Poster (2001, December 08)

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See detail2-Alkyl-3-alkylamino-2H-benzo- and pyridothiadiazine 1,1-dioxides: from K+ATP channel openers to Ca++ channel blockers?
Ouedraogo, R.; Becker, B.; Boverie, S. et al

in Biological Chemistry (2002), 383

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See detail2-Aminopropane-1,2,3-tricarboxylic acid: Synthesis and co-crystallization with the class A beta-lactamase BS3 of Bacillus licheniformis.
Beck, Josephine; Sauvage, Eric ULg; Charlier, Paulette ULg et al

in Bioorganic & Medicinal Chemistry Letters (2008), 18(13), 3764-8

The title compound 4 has been prepared in four steps from ethylglycinate in 63% overall yield. This amino analog of citric acid has been co-crystallized with the class A beta-lactamase BS3 of Bacillus ... [more ▼]

The title compound 4 has been prepared in four steps from ethylglycinate in 63% overall yield. This amino analog of citric acid has been co-crystallized with the class A beta-lactamase BS3 of Bacillus licheniformis and the structure of the complex fully analyzed by X-ray diffraction. Tris-ethyl aminocitrate 3 and the free tris-acid 4 have been tested against a member beta-lactamase from all distinct subgroups. They are novel inhibitors of class A beta-lactamases, still modest but more potent than citrate and isocitrate. [less ▲]

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See detail(+/-)-2-Benzoyl-8-ethyl-1,2-dihydro-isoquinoline-1-carbonitrile: an original Reissert compound
Graulich, Amaury ULg; Norberg, B.; Liégeois, Jean-François ULg et al

in Acta Crystallographica Section E-Structure Reports Online (2007), 63(Part 7), 3161-3073

The title compound, C19H16N2O, is a Reissert compound. The heterocyclic fragment of the molecule exhibits a 1,3-diplanar conformation. The phenyl ring is connected to the isoquinoline ring system via an ... [more ▼]

The title compound, C19H16N2O, is a Reissert compound. The heterocyclic fragment of the molecule exhibits a 1,3-diplanar conformation. The phenyl ring is connected to the isoquinoline ring system via an amide bond that adopts an anti conformation with respect to the adjacent C-N bond in the adjacent heterocyclic ring. Intra-and intermolecular C-H center dot center dot center dot O hydrogen bonds are present in the crystal structure. [less ▲]

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See detail2-ethoxycarbonyl-2-methyl-3,4-dihydro-2H-pyrrole-1-oxide: evaluation of the spin trapping properties
Olive, Gilles ULg; Mercier, Anne; Le Moigne, François et al

in Free Radical Biology & Medicine (2000), 28(3), 403-408

The 2-ethoxycarbonyl-2-methyl-3,4-dihydro-2H-pyrrole-l-oxide (EMPO), an easily prepared pyrroline-Noxide has been tested as a free radical scavenger. Spin adducts of superoxide, hydroxyl radical, and ... [more ▼]

The 2-ethoxycarbonyl-2-methyl-3,4-dihydro-2H-pyrrole-l-oxide (EMPO), an easily prepared pyrroline-Noxide has been tested as a free radical scavenger. Spin adducts of superoxide, hydroxyl radical, and other free radicals were characterized in phosphate buffer at pH 7.0 and 5.6. At pH 7 in phosphate buffer, the EMPO/O2 2• spin adduct was estimated to be about five times more persistent than its DMPO analogue. Furthermore, its decay does not produce the EMPO/HO• adduct. [less ▲]

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See detail2-N-alkylation of 3-alkylamino-substituted 2H-benzo- and 2H-pyridothiadiazine 1,1-dioxides: from K+ATP channel openers to Ca++ channel blockers?
De Tullio, Pascal ULg; Ouedraogo, R.; Becker, B. et al

in Fundamental & Clinical Pharmacology (2002)

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See detail2-nitrobenzyl esters of penam and cephem derivatives as inhibitors of penicillin-binding proteins
Brulé, Cédric; Grugier, Jérôme; Brans, Alain ULg et al

in Asian Journal of Organic Chemistry (2013), 2

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See detail2-oxepane-1,5-dione: a precursor of a novel class of versatile semicrystalline biodegradable (co)-polyesters
Lecomte, Philippe ULg; Latere Dwan'Isa, Jean-Pierre; Dubois, Philippe et al

Poster (2003, July 01)

2-oxepane-1,5-dione (OPD) was synthesized by Baeyer-Villiger oxidation of 1,4-cyclohexanedione and ring-opening polymerized by 1-phenyl-2-propanol / tin octoate with formation of a semicrystalline ... [more ▼]

2-oxepane-1,5-dione (OPD) was synthesized by Baeyer-Villiger oxidation of 1,4-cyclohexanedione and ring-opening polymerized by 1-phenyl-2-propanol / tin octoate with formation of a semicrystalline polyester of high melting temperature (Tm: 147°C). A crystallographic study showed that the polyester is orthorombic in the P212121 space with two molecules extended along the c-axis as is the case for poly(ε-caprolactone) (PCL). Dibutyltin dimethoxide and 2,2-dibutyl-2-stanna-1,3-dioxepane (DSDOP) proved to be efficient initiators for the random copolymerization of ε-caprolactone (εCL) and OPD. Random distribution of the comonomer units was confirmed by DSC, 1H and 13C NMR analyses. A single Tm was observed, which varies regularly and monotonically with the OPD content as result of a cocrystallisation phenomenon. The single glass transition temperature (Tg) obeys the Fox equation. It is noteworthy that a copolymer containing 30 mol % OPD exhibits a Tm of 90°C. It is stable up to 140°C under nitrogen for one hour, such that processing by extrusion is quite possible. The OPD decomposition is maximum at 223°C for a heating rate of 10°C/min. The mechanism of thermal degradation was investigated and cleared up. The ketone increases the copolymer hydrophilicity and thus sensitivity to hydrolysis. The mechanical properties are quite reminiscent of PCL of comparable molecular weight. Quite interestingly, OPD imparts sensitivity to photo-cross-linking to this novel class of materials. [less ▲]

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See detail2-oxepane-1,5-dione: a precursor of a novel class of versatile semicrystalline biodegradable (co)-polyesters
Latere Dwan'Isa, Jean-Pierre; Lecomte, Philippe ULg; Dubois, Philippe et al

Poster (2003, May 16)

2-oxepane-1,5-dione (OPD) was synthesized by Baeyer-Villiger oxidation of 1,4 cyclohexanedione and ring-opening polymerized by 1-phenyl- 2-propanol / tin octoate with formation of a semicrystalline ... [more ▼]

2-oxepane-1,5-dione (OPD) was synthesized by Baeyer-Villiger oxidation of 1,4 cyclohexanedione and ring-opening polymerized by 1-phenyl- 2-propanol / tin octoate with formation of a semicrystalline polyester of high melting temperature (Tm :147°C). Dibutyin dimethoxide and 2,2-dibutyl-2-stanna-1,3-dioxepane (DSDOP) proved to be efficient initiators for the random copolymerization of ε-caprolactone (εCL) and OPD. Random distribution of the comonomer units was confirmed by DSC, 1H and 13C NMR analyses. A single Tm was observed, which varies regularly and monotonically with the OPD content as result of a cocrystallisation phenomenon. The single glass transition temperature (Tg) obeys the Fox equation. It is noteworthy that a copolymer containing 30 mol % OPD exhibits a Tm of 90°C. It is stable up to 140°C under nitrogen for one hour, such that processing by extrusion is quite possible. The OPD decomposition is maximum at 223°C for a heating rate of 10°C/min. The mechanism of thermal degradation was investigated and cleared up. The ketone increases the copolymer hydrophilicity and thus sensitivity to hydrolysis. The mechanical properties are quite reminiscent of PCL of comparable molecular weight. Quite interestingly, OPD imparts sensitivity to photo-cross-linking to this novel class of materials. [less ▲]

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See detail2-oxepane-1,5-dione: A precursor of a novel class of versatile semicrystalline biodegradable (Co)polyesters
Latere, Jean-Pierre; Lecomte, Philippe ULg; Dubois, Philippe ULg et al

in Macromolecules (2002), 35(21), 7857-7859

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See detail2-Point correlation function of nanostructured materials via the grey-tone correlation function of electron tomograms: A three-dimensional structural analysis of ordered mesoporous silica
Gommes, Cédric ULg; Friedrich, Heiner; De Jongh, Petra E et al

in Acta Materialia (2010), 58

Electron tomography is a unique technique for imaging the microstructure of materials with a nanometer resolution. The signal to noise ratio of electron tomograms is, however, often too low for a reliable ... [more ▼]

Electron tomography is a unique technique for imaging the microstructure of materials with a nanometer resolution. The signal to noise ratio of electron tomograms is, however, often too low for a reliable segmentation-based image analysis. We derive a general relation between the grey-tone correlation function of the tomograms and the 2-point correlation function of the morphology, which enables to analyze quantitatively the grey-tone correlation function with a morphological model of the material. The methodology is applied to SBA-15 ordered mesoporous silica. The three-dimensional grey-tone correlation function obtained from electron tomography is analyzed in terms of a hexagonal array of Gaussian independent pores. The model enables to relate the morphology obtained from the 2-point correlation function to macroscopic characterization data of the material, notably small-angle X-ray scattering and nitrogen adsorption. [less ▲]

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See detailA 2-step methodology for the generation of accurate FE models of nonlinear systems,
Kerschen, Gaëtan ULg; Golinval, Jean-Claude ULg

in ASME Internaional Mechanical Engineering Congress, Anaheim, 2004 (2004, November)

Model updating and validation is currently a central issue in the fields of computational structural mechanics and dynamics. The vast majority of applications however concerns linear structures. On the ... [more ▼]

Model updating and validation is currently a central issue in the fields of computational structural mechanics and dynamics. The vast majority of applications however concerns linear structures. On the other hand, updating nonlinear models is something the structural dynamicist prefers to avoid mainly because tools such as modal analysis are no longer available. The objective of the present study is to propose a two-step methodology for dealing with nonlinear systems. Its most appealing feature is that it decouples the estimation of the linear and nonlinear parameters. A numerical application consisting of an aeroplane-like structure is used to assess the efficiency of the procedure. [less ▲]

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See detailA 2-year phase II study with 1-year of follow-up of risedronate (NE58095) in postmenopausal osteoporosis
Clemmesen, B; Ravn, P; Zegels, Brigitte ULg et al

in Osteoporosis International (1997), 7

Detailed reference viewed: 8 (4 ULg)