Browsing
     by title


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

or enter first few letters:   
OK
Peer Reviewed
See detailThe isomerization and fragmentation of the CHO2+ ions: an example of spin-controlled chemistry?
Petitjean, Serge; Dehareng, Dominique ULg; Praet, Marie-Thérèse et al

in Advances in Mass Spectrometry (1985), X(B), 1129-1130

The article presents a study of the isomerization and fragmentation of the CHO2+ ions

Detailed reference viewed: 16 (1 ULg)
Full Text
Peer Reviewed
See detailThe isomerization of oxirane. Stable .CH2OCH2., .CH2CH2O. and :CHOCH3 and Their Counterpart Ions
Wesdemiotis, Chrysostomos; Leyh, Bernard ULg; Fura, Aberra et al

in Journal of the American Chemical Society (1990), 112

Detailed reference viewed: 7 (1 ULg)
Full Text
See detailISON (C/2012 S1)
Manfroid, Jean ULg

Article for general public (2013)

Detailed reference viewed: 9 (0 ULg)
See detailIsoperimetric geometry
Bogaert, Jan ULg

Learning material (2003)

Detailed reference viewed: 23 (5 ULg)
Full Text
Peer Reviewed
See detailIsoprene and monoterpene emissions from a mixed temperate forest
Laffineur, Quentin ULg; Aubinet, Marc ULg; Schoon, N. et al

in Atmospheric Environment (2011), 45

Detailed reference viewed: 24 (2 ULg)
Full Text
See detailIsoprene and monoterpene emissions from a mixed temperate forest
Laffineur, Quentin ULg; Heinesch, Bernard ULg; Amelynck, Crist et al

Poster (2011, April 07)

Detailed reference viewed: 51 (10 ULg)
Full Text
Peer Reviewed
See detailIsoprene-assisted radical coupling of (co)polymers prepared by cobalt-mediated radical polymerization
Debuigne, Antoine ULg; Jérôme, Christine ULg; Detrembleur, Christophe ULg

in Angewandte Chemie (International ed. in English) (2009), 48(8), 1422-1424

The isoprene-assisted radical coupling (I-ARC) of polymers prepared by cobalt-mediated radical polymerization (see picture) is the first efficient radical coupling method that is not restricted to short ... [more ▼]

The isoprene-assisted radical coupling (I-ARC) of polymers prepared by cobalt-mediated radical polymerization (see picture) is the first efficient radical coupling method that is not restricted to short chains. When applied to AB diblock copolymers, I-ARC constitutes a straightforward approach to the preparation of novel symmetrical ABA triblock copolymers [less ▲]

Detailed reference viewed: 48 (16 ULg)
Full Text
Peer Reviewed
See detailIsoprenoid metabolism in aphid : A new target for bioinsecticides development
Vandermoten, Sophie ULg; Charloteaux, Benoît ULg; Santini, Sébastien et al

Poster (2008, July)

Detailed reference viewed: 25 (6 ULg)
Peer Reviewed
See detailIsoproturon as a model to illustrate the ELISA method for the detection and quantitation of pesticides in environment
Liegeois, Eric; Dehon, Yves; De Brabant, Bernard et al

in Proceedings of the International Symposium Environmental Biotechnology (1991, April)

Detailed reference viewed: 6 (0 ULg)
Full Text
Peer Reviewed
See detailIsopyoverdin Pp BTP1, a biogenetically interesting novel siderophore from Pseudomonas putida
Jacques, Philippe; Gwose, Inga; Seinsche, Dieter et al

in Natural Product Letters (1993), 3

From the cultures of Pseudomonas putida BTP 1 a siderophore could be isolated which contains the chromophore 2a rather than 1a typical for pyoverdins. Its structure was elucidated by MS, NHR and chemical ... [more ▼]

From the cultures of Pseudomonas putida BTP 1 a siderophore could be isolated which contains the chromophore 2a rather than 1a typical for pyoverdins. Its structure was elucidated by MS, NHR and chemical degradation. This new structural type is of great interest. The currently accepted biogenetic pathway leading to 1a starts from D-Tyr and L-Dab which condense to give the ferribactin chromophore 4. Subsequent ring closure via the -nitrogen of Dab leads to 1a while alternative ring closure via the -nitrogen would yield 2a. It is for the first time that this iso-chromophore has been detected in a Pseudomonas siderophore. Its discovery confirms the assumed intermediacy of ferribactine in the biogenesis of pyoverdins. [less ▲]

Detailed reference viewed: 27 (2 ULg)
Full Text
Peer Reviewed
See detailIsostables, isochrons, and Koopman spectrum for the action-angle representation of stable fixed point dynamics
Mauroy, Alexandre ULg; Mezić, Igor; Moehlis, Jeff

in Physica D: Nonlinear Phenomena (2013), 261

For asymptotically periodic systems, a powerful (phase) reduction of the dynamics is obtained by computing the so-called isochrons, i.e. the sets of points that converge toward the same trajectory on the ... [more ▼]

For asymptotically periodic systems, a powerful (phase) reduction of the dynamics is obtained by computing the so-called isochrons, i.e. the sets of points that converge toward the same trajectory on the limit cycle. Motivated by the analysis of excitable systems, a similar reduction has been attempted for non-periodic systems admitting a stable fixed point. In this case, the isochrons can still be defined but they do not capture the asymptotic behavior of the trajectories. Instead, the sets of interest - that we call " isostables" - are defined in the literature as the sets of points that converge toward the same trajectory on a stable slow manifold of the fixed point. However, it turns out that this definition of the isostables holds only for systems with slow-fast dynamics. Also, efficient methods for computing the isostables are missing. The present paper provides a general framework for the definition and the computation of the isostables of stable fixed points, which is based on the spectral properties of the so-called Koopman operator. More precisely, the isostables are defined as the level sets of a particular eigenfunction of the Koopman operator. Through this approach, the isostables are unique and well-defined objects related to the asymptotic properties of the system. Also, the framework reveals that the isostables and the isochrons are two different but complementary notions which define a set of action-angle coordinates for the dynamics. In addition, an efficient algorithm for computing the isostables is obtained, which relies on the evaluation of Laplace averages along the trajectories. The method is illustrated with the excitable FitzHugh-Nagumo model and with the Lorenz model. Finally, we discuss how these methods based on the Koopman operator framework relate to the global linearization of the system and to the derivation of special Lyapunov functions. © 2013 Elsevier B.V. All rights reserved. [less ▲]

Detailed reference viewed: 9 (0 ULg)
Full Text
Peer Reviewed
See detailIsostrychnopentamine, an indolomonoterpenic alkaloid from Strychnos usambarensis, induces cell cycle arrest and apoptosis in human colon cancer cells
Frederich, Michel ULg; Bentires-Alj, M.; Tits, Monique ULg et al

in Journal of Pharmacology and Experimental Therapeutics (2003), 304(3), 1103-1110

Isostrychnopentamine (ISP) is an indolomonoterpenic alkaloid that is present in the leaves of Strychnos usambarensis, a well known African shrub or little tree. The roots contain quaternary alkaloids ... [more ▼]

Isostrychnopentamine (ISP) is an indolomonoterpenic alkaloid that is present in the leaves of Strychnos usambarensis, a well known African shrub or little tree. The roots contain quaternary alkaloids, which are used to make a curare-like arrow poison. However, tertiary alkaloids isolated from the same plant possess cytotoxic activities against mammalian cells and protozoa. The effect of ISP has been investigated on the growth and viability of HCT-116 colon cancer cells during their exponentially growing phase. ISP induced apoptotic cell death as shown by the translocation of phosphatidylserine from the inner layer to the outer layer of the plasma membrane, chromatin condensation, DNA fragmentation, and caspase-3 and -9 activation. ISP provoked also cell cycle arrest in the G(2)-M phase. We also showed that the expression of p53 was not modified in ISP-treated cells, but that p21 was induced in a p53-independent manner. Finally, we demonstrated that ISP did not affect the catalytic activity of human topoisomerases I and II. In conclusion, ISP, which promotes cell death by a p53-independent apoptotic pathway, could be an interesting lead for cancer chemotherapy. [less ▲]

Detailed reference viewed: 26 (10 ULg)
Full Text
Peer Reviewed
See detailIsostrychnopentamine, an Indolomonoterpenic Alkaloid from Strychnos usambarensis, with Potential Antitumor Activity against Apoptosis-Resistant Cancer Cells
Balde, El-Hadj Saidou; Mégalizzi, Véronique; Angenot, Luc ULg et al

in International Journal of Oncology (2010), 36

Detailed reference viewed: 60 (19 ULg)
Peer Reviewed
See detailThe isothermal melt-texturing of bulk YBa2Cu3O7-x ceramics: from cooking to modelling
Vandewalle, Nicolas ULg

in Superconductor Science and Technology (1998), 11(1), 35-43

Various techniques for the synthesis of bulk YBa2Cu3O7-x ceramics are reviewed. The microstructure of melt-textured YBa2Cu3O7-x compounds is described. In contrast to the relatively simple processing of ... [more ▼]

Various techniques for the synthesis of bulk YBa2Cu3O7-x ceramics are reviewed. The microstructure of melt-textured YBa2Cu3O7-x compounds is described. In contrast to the relatively simple processing of such materials, the complexity of the microstructure at a mesoscopic scale is underlined. A model describing the various features of the microstructure of YBa2Cu3O7-x compounds is described. The obtained results are discussed for various initial conditions and are favourably comparable with experimental findings. [less ▲]

Detailed reference viewed: 10 (1 ULg)
See detailIsothermal titration calorimetry as a tool for improving enzymatic lignocellulose hydrolysis
Razafindralambo, Hary ULg; Boquel, Pascal; Jacquet, Nicolas ULg et al

Conference (2008, December)

Detailed reference viewed: 21 (9 ULg)
Full Text
Peer Reviewed
See detailIsotope Analysis Reveals Foraging Area Dichotomy for Atlantic Leatherback Turtles
Caut, Stéphane ULg; Guirlet, Elodie ULg; Angulo, Elena et al

in PLoS ONE (2008), 3(3), 1845

Background: The leatherback turtle (Dermochelys coriacea) has undergone a dramatic decline over the last 25 years, and this is believed to be primarily the result of mortality associated with fisheries ... [more ▼]

Background: The leatherback turtle (Dermochelys coriacea) has undergone a dramatic decline over the last 25 years, and this is believed to be primarily the result of mortality associated with fisheries bycatch followed by egg and nesting female harvest. Atlantic leatherback turtles undertake long migrations across ocean basins from subtropical and tropical nesting beaches to productive frontal areas. Migration between two nesting seasons can last 2 or 3 years, a time period termed the remigration interval (RI). Recent satellite transmitter data revealed that Atlantic leatherbacks follow two major dispersion patterns after nesting season, through the North Gulf Stream area or more eastward across the North Equatorial Current. However, information on the whole RI is lacking, precluding the accurate identification of feeding areas where conservation measures may need to be applied. Methodology/Principal Findings: Using stable isotopes as dietary tracers we determined the characteristics of feeding grounds of leatherback females nesting in French Guiana. During migration, 3-year RI females differed from 2-year RI females in their isotope values, implying differences in their choice of feeding habitats (offshore vs. more coastal) and foraging latitude (North Atlantic vs. West African coasts, respectively). Egg-yolk and blood isotope values are correlated in nesting females, indicating that egg analysis is a useful tool for assessing isotope values in these turtles, including adults when not available. Conclusions/Significance: Our results complement previous data on turtle movements during the first year following the nesting season, integrating the diet consumed during the year before nesting. We suggest that the French Guiana leatherback population segregates into two distinct isotopic groupings, and highlight the urgent need to determine the feeding habitats of the turtle in the Atlantic in order to protect this species from incidental take by commercial fisheries. Our results also emphasize the use of eggs, a less-invasive sampling material than blood, to assess isotopic data and feeding habits for adult female leatherbacks. [less ▲]

Detailed reference viewed: 95 (13 ULg)
Full Text
Peer Reviewed
See detailIsotope coded protein label quantification of serum proteins--comparison with the label-free LC-MS and validation using the MRM approach.
Turtoi, Andrei ULg; Mazzucchelli, Gabriel ULg; De Pauw, Edwin ULg

in Talanta (2010), 80(4), 1487-95

Protein quantification based upon mass spectrometry is gaining ground in diverse applications of biological and clinical relevance. The present article focuses on one of the most complex biological fluids ... [more ▼]

Protein quantification based upon mass spectrometry is gaining ground in diverse applications of biological and clinical relevance. The present article focuses on one of the most complex biological fluids - serum - and provides a novel ICPL based quantification protocol. The results are compared to a label-free (data independent alternate scanning) absolute quantification method. The validation is performed using MRM based protein quantification technique. Regarding the ICPL approach, serum samples used in this study were depleted of high abundant proteins, labeled with ICPL and fractionated according to their respective pI (3-5, 5-7 and 7-12). The samples were further subjected to tryptic digestion followed by treatment with the Glu-C enzyme. The peptides were analyzed on a 2D-nano-LC system using four different concentrations of salt injections (45, 75, 150 and 500 mM ammonium acetate). The LC system was connected on-line with the electrospray ion-trap mass spectrometer. For the label-free quantification the serum samples were depleted and digested with trypsin. A proteome-wide comparison was performed using highly reproducible LC and data independent alternate scanning in conjunction with a high mass accuracy orthogonal time-of-flight mass spectrometer. Selected proteins, found by both methods, were validated using the MRM approach. For this purpose non-depleted tryptically digested serum samples were analyzed by LC coupled with a triple-quadrupole MS. The relative protein quantification using ICPL and mass spectrometry allowed for the detection of approximately 200 proteins, whereas about 2/3 of those contained the ICPL label and could therefore be quantified. Label-free approach used no fractionation, less sample and was able to identify and quantify over 110 proteins. The identified proteins covered generally 3-4 orders of magnitude of protein concentration in human serum. Changes in relative abundance of eight proteins were validated using MRM. This study, for the first time, shows the ability of the relative protein quantification based upon ICPL and 2D-LC-MS/MS to quantify serum biomarkers. It provides two additional label-free approaches that could validate and bring additional value to the label-based results, offering a starting point for comprehensive proteomics studies aiming at revealing biomarkers of clinical relevance. [less ▲]

Detailed reference viewed: 195 (49 ULg)