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See detailInterest of a prescreening questionnaire to reduce the cost of bone densitometry
Ben Sedrine, Wafa ULg; Broers, P.; Devogelaer, J. P. et al

in Osteoporosis International (2002), 13(5), 434-442

Bone mineral density (BMD) measurement is widely recognized as the best single tool to identify patients with a high lifetime risk of developing an osteoporosis-related fracture. However, the cost/benefit ... [more ▼]

Bone mineral density (BMD) measurement is widely recognized as the best single tool to identify patients with a high lifetime risk of developing an osteoporosis-related fracture. However, the cost/benefit value of screening the whole population has been repeatedly challenged and demonstrated to be rather poor. In many countries, BMD scan is not or no longer reimbursed because of lack of validated criteria to identify patients who should benefit from this procedure. Based on the proposals of a nationwide expert panel, a simple questionnaire identifying historical, clinical and behavioral risk factors for osteoporosis was developed. The aim of this study was to assess the diagnostic accuracy of the proposed criteria; to determine the extent to which this questionnaire could be useful for optimizing the use of densitometry tests; and, more specifically, to estimate the diagnostic costs per osteoporotic or osteopenic patient detected. For this purpose, we applied the questionnaire to 3998 consecutive individuals at least 20 years old, of both genders, either consulting spontaneously or referred for a BMD measurement to an outpatient osteoporosis center. BMD was measured by dual-energy X-ray absorptiometry (DXA) at the lumbar spine and at the hip (both total hip and femoral neck). Diagnostic accuracies were evaluated through measures of sensitivity, specificity, and positive and negative predictive values. After determining a benchmark value for age, different strategies were compared in order to identify the most cost-effective one in terms of cost per patient detected. According to the WHO operational definition of osteoporosis (T-score <-2.5), 31% of the subjects were classified as osteoporotic at one or more of the measured sites. If only patients with at least one of the proposed risk factors had been referred for scans, 33.3% of the BMD measurements would have been avoided. Among those, less than 5% were missclassified as they did have osteoporosis at the total hip and up to 23% at one or more of the considered sites. On the other hand, of the subjects who would be recommended for a densitometry test, only a small fraction were identified correctly (the positive predictive values varied from 11.3% at the total hip to 34.8% at any site). In this first setting, the suggested criteria seem useful chiefly for excluding subjects who do not need a DXA scan rather than selecting osteoporotic patients. When applied only to patients aged 61 years or more, the positive predictive values rose to 15.1% (total hip) and 42.9% (any site), whereas the corresponding negative predictive values were set at 93% and 68.6%. In comparison, with a mass screening scenario the estimated diagnostic costs (costs associated with the DXA procedure) per osteoporotic patient detected at any of the considered sites would be reduced by more than 9% (59.4 instead of 65.3 Euros) if the suggested indications are taken into account for prescreening patients. And when the questionnaire is applied only to women over the age of 60 years these costs would be further reduced to 50.6 Euros, representing a 23% decrease. Then, a prescreening strategy based on these indications concomitantly with an age-selective criterion could represent a promising way toward a more rational use of BMD measurement. [less ▲]

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See detailDetermination of the free/included piroxicam ratio in cyclodextrin complexes: comparison between UV spectrophotometry and differential scanning calorimetry
Van Hees, Thierry ULg; Piel, Géraldine ULg; Henry de Hassonville, Sandrine et al

in European Journal of Pharmaceutical Sciences (2002), 15(4), 347-353

Few analytical techniques allow to evaluate the inclusion yield of cyclodextrin-drug complexes, because most manufacturing processes give amorphous products, In this study we have developed an alternative ... [more ▼]

Few analytical techniques allow to evaluate the inclusion yield of cyclodextrin-drug complexes, because most manufacturing processes give amorphous products, In this study we have developed an alternative method to differential scanning calorimetry, to accurately determine the free/complexed piroxicam ratio by UV spectroscopy. This method is based on the differential solubility of the piroxicam-beta-cyclodextrin 1:2.5 mol/mol complex in water-acetonitrile (1:1 v/v) (Solvent A) or in anhydrous acetonitrile (Solvent B). both containing 0.05 M HCl. In anhydrous acetonitrile, beta-cyclodextrin is insoluble and the included drug remains entrapped, allowing the free piroxicam determination, while with 50% of water, the complex is totally dissolved, allowing the determination of the total guest content. This method was validated for linearity, precision and accuracy. The presence of cyclodextrin does not influence the assays, but more than 0.5% of water in Solvent B significantly affects the determination of the free piroxicam content. In comparison with differential scanning calorimetry, both delectability and precision were improved. It is now possible to analyse complexes with an inclusion purity greater than 99%. (C) 2002 Elsevier Science B.V. All rights reserved. [less ▲]

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See detailPersistent infection of human thymic epithelial cells by coxsackievirus B4
Brilot, F.; Chehadeh, W.; Charlet-Renard, C. et al

in Journal of Virology (2002), 76(10), 5260-5265

Persistent replication of coxsackievirus B4 (CVB4) E2 (diabetogenic) and CVB4 JBV (nondiabetogenic) strains in thymic epithelial cell (TEC)-enriched cultures (>or=95%) was proved by detection of positive ... [more ▼]

Persistent replication of coxsackievirus B4 (CVB4) E2 (diabetogenic) and CVB4 JBV (nondiabetogenic) strains in thymic epithelial cell (TEC)-enriched cultures (>or=95%) was proved by detection of positive- and negative-strand viral RNA by reverse transcription-PCR in extracted RNA from cell cultures, VP1 capsid protein detection by immunofluorescence (IF) staining, and release of infectious particles up to 30 days after infection without obvious cytolysis. By double-IF staining, cytokeratin-containing cells were shown to be susceptible to CVB4. The persistence of CVB4 was associated with a significantly increased rate of TEC proliferation (up to 70%) after 20 days of culture and a significantly increased chronic production of immunoreactive interleukin-6 (IL-6), leukemia inhibitory factor, and granulocyte-macrophage colony-stimulating factor in supernatant after 3 days of culture. The CVB4 replication and the release of cytokines were not restricted to the CVB4 E2 diabetogenic strain and did not depend on the genetic background of the host; however, TEC were more responsive to CVB4 E2 than CVB4 JBV as far as the production of cytokines. [less ▲]

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See detailAn empirical formula for L line X-ray production cross-section of elements from Ag to U for protons below 3.5 MeV
Strivay, David ULg; Weber, Georges ULg

in Nuclear Instruments & Methods in Physics Research. Section B, Beam Interactions with Materials and Atoms (2002), 190

When computing element concentration from proton induced X-ray emission analysis, an important parameter is the X-ray production cross-section. There have been numerous experimental and theoretical works ... [more ▼]

When computing element concentration from proton induced X-ray emission analysis, an important parameter is the X-ray production cross-section. There have been numerous experimental and theoretical works in this field. Nonetheless, although there is a simple analytical formula to compute K X-ray cross-sections, there is no such ones for the L lines. We present here analytical formulas for the cross-section of the three main X-ray lines L-alpha L-beta and L-gamma based on experimental data. So far, nearly 3000 values of cross-sections for elements from Ag to U and proton energy ranging from 0.5 to 3.5 MeV have been collected from various references. This experimental data set has been fitted for each Xray line with an exponential function depending on the proton energy and on the element atomic number. These fitted values have then been compared to the experimental data and with theoretical values obtained by the ECPSSR theory and Coster-Kronig fluorescence yields. (C) 2002 Elsevier Science B.V. All rights reserved. [less ▲]

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See detailByssoloma llimonae sp nov., from continental Spain, Madeira and the Canary Islands
Sérusiaux, Emmanuel ULg; Gomez-Bolea, A.; Longan, A. et al

in Lichenologist (2002), 34(Part 3), 183-188

Byssoloma llimonae, a new species described from NE Spain, Madeira and the Canary Islands (Gomera, La Palma and Tenerife), is a mostly corticolous species, closely related to the more widespread and ... [more ▼]

Byssoloma llimonae, a new species described from NE Spain, Madeira and the Canary Islands (Gomera, La Palma and Tenerife), is a mostly corticolous species, closely related to the more widespread and usually foliicolous Bapalmuia kakouettae (=Byssoloma aptrootii). The generic position of this group of species within the Pilocarpaceae is still unclear. The new combination Byssoloma kakouettae (Serus.) R. Lucking [less ▲]

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See detailStrychnohexamine from Strychnos icaja, a naturally occurring trimeric indolomonoterpenic alkaloid
Philippe, Geneviève ULg; Prost, E.; Nuzillard, J. M. et al

in Tetrahedron Letters (2002), 43(18), 3387-3390

A reinvestigation of Strychnos icaja roots has resulted in the isolation, from the EtOAC extract, of one tertiary trisindole alkaloid, named strychnohexamine. Its structure has been investigated by means ... [more ▼]

A reinvestigation of Strychnos icaja roots has resulted in the isolation, from the EtOAC extract, of one tertiary trisindole alkaloid, named strychnohexamine. Its structure has been investigated by means of spectroscopic data interpretation (UV. IR. HRESIMS. 1D and 2D NMR). This is the first time that a natural trimeric indolomonoterpenic alkaloid has been isolated directly from a plant species. This compound is one of the largest alkaloids ever discovered. (C) 2002 Elsevier Science Ltd. All rights reserved. [less ▲]

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See detailpH-Dependence of the morphology of micelles formed by poly(2-vinylpyridine)-block-poly(ethylene oxide) copolymers in water
Gohy, Jean-François; Mores, Sandrine; Varshney, Sunil K et al

in e-Polymers (2002), (21), 1-8

The morphology of micelles formed by two poly(2-vinylpyridine)-block-poly(ethylene oxide) (P2VP-b-PEO) copolymers has been studied in phosphate-buffered water by dynamic light scattering and transmission ... [more ▼]

The morphology of micelles formed by two poly(2-vinylpyridine)-block-poly(ethylene oxide) (P2VP-b-PEO) copolymers has been studied in phosphate-buffered water by dynamic light scattering and transmission electron microscopy. Spherical micelles are observed when the P2VP block is the minor component of the diblock copolymer. When P2VP dominates the composition, transition from spheres-to-rods-to-vesicles takes place in a narrow pH range that straddles the pKa of P2VP. This transition is controlled by the degree of protonation of the P2VP blocks. At high pH, the copolymer precipitates from the solution. [less ▲]

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See detailControlled ring-opening polymerization of epsilon-caprolactone in the presence of layered silicates and formation of nanocomposites
Kubies, Dana; Pantoustier, Nadège; Dubois, Philippe et al

in Macromolecules (2002), 35

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See detailThe origin of catecholaminergic inputs to the song control nucleus RA in canaries
Appeltants, D.; Ball, G. F.; Balthazart, Jacques ULg

in Neuroreport (2002), 13(5), 649-653

Song control nuclei in oscines receive dense catecholaminergic inputs but their anatomical origin is poorly understood. We analyzed catecholaminergic inputs to the nucleus robustus archistriatalis (RA) in ... [more ▼]

Song control nuclei in oscines receive dense catecholaminergic inputs but their anatomical origin is poorly understood. We analyzed catecholaminergic inputs to the nucleus robustus archistriatalis (RA) in canaries by retrograde tract-tracing combined with immunocytochemistry for tyrosine hydroxylase. In both sexes, dopaminergic inputs to RA come mostly from the A1 1 (mesencephalic central gray) and A10 (area ventralis of Tsai) cell groups but the locus coeruleus and subcoeruleus (A6) also send noradrenergic projections to RA. No input originates in the hypothalamic and in the A5 to A1 catecholaminergic groups. These findings and previous work on the high vocal center (HVc) indicate that the two major nuclei of the motor pathway controlling song production (RA and HVc) receive catecholaminergic inputs of similar origins. [less ▲]

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See detailLifetime measurements for doubly ionized uranium
Biémont, Emile ULg; Palmeri, P.; Quinet, Pascal ULg et al

in Journal of Physics B-Atomic Molecular and Optical Physics (2002), 35(7), 1701-1705

The first lifetime measurements for doubly ionized uranium are reported in the present work. They relate to five levels belonging to the configurations 5f(2)6d(2), 5f(2)6d7s and 5f(3)7p and have been ... [more ▼]

The first lifetime measurements for doubly ionized uranium are reported in the present work. They relate to five levels belonging to the configurations 5f(2)6d(2), 5f(2)6d7s and 5f(3)7p and have been obtained with a time-resolved laser-induced-fluorescence technique, the ions being produced by laser ablation of a uranium oxide target. [less ▲]

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See detailSubdivision of the helix-turn-helix GntR family of bacterial regulators in the FadR, HutC, MocR, and YtrA subfamilies
Rigali, Sébastien ULg; Derouaux, Adeline ULg; Giannotta, F. et al

in Journal of Biological Chemistry (2002), 277(15), 12507-12515

Haydon and Guest (Haydon, D. J, and Guest, J. R. (1991) FEMS Microbiol Lett. 63, 291-295) first described the helix-turn-helix GntR family of bacterial regulators. They presented them as transcription ... [more ▼]

Haydon and Guest (Haydon, D. J, and Guest, J. R. (1991) FEMS Microbiol Lett. 63, 291-295) first described the helix-turn-helix GntR family of bacterial regulators. They presented them as transcription factors sharing a similar N-terminal DNA-binding (D-b) domain, but they observed near-maximal divergence in the C-terminal effector-binding and oligomerization (E-b/O) domain. To elucidate this C-terminal heterogeneity, structural, phylogenetic, and functional analyses were performed on a family that now comprises about 270 members. Our comparative study first focused on the C-terminal E-b/O domains and next on DNA-binding domains and palindromic operator sequences, has classified the GntR members into four subfamilies that we called FadR, HutC, MocR, and YtrA. Among these subfamilies a degree of similarity of about 55% was observed throughout the entire sequence. Structure/function associations were highlighted although they were not absolutely stringent. The consensus sequences deduced for the DNA-binding domain were slightly different for each subfamily, suggesting that fusion between the D-b and E-b/O domains have occurred separately, with each subfamily having its own D-b domain ancestor. Moreover, the compilation of the known or predicted palindromic cis-acting elements has highlighted different operator sequences according to our subfamily subdivision. The observed C-terminal E-b/O domain heterogeneity was therefore reflected on the DNA-binding domain and on the cis-acting elements, suggesting the existence of a tight link between the three regions involved in the regulating process. [less ▲]

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See detailElectrografting of preformed aliphatic polyesters onto metallic surfaces
Lou, Xudong; Jérôme, Christine ULg; Detrembleur, Christophe ULg et al

in Langmuir (2002), 18(7), 2785-2788

Preformed aliphatic polyesters bearing pendent acrylate groups, poly(4-acryloyloxy-epsilon-caprolactone)co-epsilon-caprolactone) [poly(ACL-co-epsilonCL)], were grafted onto metallic surfaces by a cathodic ... [more ▼]

Preformed aliphatic polyesters bearing pendent acrylate groups, poly(4-acryloyloxy-epsilon-caprolactone)co-epsilon-caprolactone) [poly(ACL-co-epsilonCL)], were grafted onto metallic surfaces by a cathodic electrochemical process. Content of acrylates must exceed a lower limit for them to be adsorbed on the cathode with the proper orientation and for the grafting to be successful. The strongly adhering films were analyzed by IR reflection-absorption spectroscopy and scanning electron microscopy. As a result of the known miscibility of poly-e-caprolactone with poly(vinyl chloride) (PVC), the pregrafting of poly(ACL-co-epsilonCL) imparts strong adhesion to PVC topcoats. [less ▲]

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See detailInfluence of non-adiabatic temperature variations on line profile variations of slowly rotating beta Cep stars and SPBs. I. Non-adiabatic eigenfunctions in the atmosphere of a pulsating star
Dupret, Marc-Antoine ULg; De Ridder, J.; Neuforge, C. et al

in Astronomy and Astrophysics (2002), 385

In this study, we compute theoretical line profiles of a non-radially pulsating star, taking the non-adiabatic effects into account. These non-adiabatic effects are especially important in the atmosphere ... [more ▼]

In this study, we compute theoretical line profiles of a non-radially pulsating star, taking the non-adiabatic effects into account. These non-adiabatic effects are especially important in the atmosphere, where the spectral lines are formed, and must be accounted for. In this first paper of the series, we present a new treatment of the perturbed thermal and dynamical equations in the atmosphere of a pulsating star. We apply our formalism to the computation of non-adiabatic eigenfunctions in a typical beta Cephei star with low order p-modes and in a typical slowly pulsating B star with high-order g-modes. [less ▲]

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See detailHadronic scattering amplitudes: Medium-energy constraints on asymptotic behavior
Cudell, Jean-René ULg; Ezhela, Vladimir V.; Gauron, P. et al

in Physical Review. D (2002), 65(7),

We consider several classes of analytic parametrizations of hadronic scattering amplitudes, and compare their predictions to all available forward data (pp, (p) over barp, pip, Kp, gammap, gammagamma ... [more ▼]

We consider several classes of analytic parametrizations of hadronic scattering amplitudes, and compare their predictions to all available forward data (pp, (p) over barp, pip, Kp, gammap, gammagamma, Sigmap). Although these parametrizations are very close for rootsgreater than or equal to9 GeV, it turns out that they differ markedly at low energy, where a universal Pomeron term similar toln(2)s enables one to extend the fit down to roots=4 GeV. [less ▲]

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See detailInfluence of non-adiabatic temperature variations on line profile variations of slowly rotating beta Cephei stars and SPBs. II. Simulations of line profile time series
De Ridder, J.; Dupret, Marc-Antoine ULg; Neuforge, C. et al

in Astronomy and Astrophysics (2002), 385

We investigate to what extent non-adiabatic temperature variations at the surface of slowly rotating non-radially pulsating beta Cephei stars and slowly pulsating B stars affect silicon line profile ... [more ▼]

We investigate to what extent non-adiabatic temperature variations at the surface of slowly rotating non-radially pulsating beta Cephei stars and slowly pulsating B stars affect silicon line profile variations. We use the non-adiabatic amplitudes of the effective temperature and gravity variation presented in Dupret et al. (\cite{Dupret02}), together with a Kurucz intensity grid, to compute time series of line profile variations. Our simulations point out that the line shapes do not change significantly due to temperature variations. We find equivalent width variations of at most two percent of the mean equivalent width. We confront our results with observational equivalent width variations and with photometrically obtained effective temperature variations. Based on observations obtained with the Swiss photometric telescope and with the ESO/CAT telescope, at La Silla in Chile. [less ▲]

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See detailV4741 Sagittarii
Gosset, Eric ULg

in International Astronomical Union Circular (2002), 7887

IAUC 7887 available at Central Bureau for Astronomical Telegrams.

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See detailLe syndrome des ongles verts ou chloronychie
Maes, M.; Richert, Bertrand ULg; de LA BRASSINNE, Michel ULg

in Revue Médicale de Liège (2002), 57(4), 233-235

"Green nails" or chloronychia is an infection mostly caused by Pseudomonas ueruginosa but also by other bacterial or fungal contamination. The clinical appearance consists in a typical triad: green ... [more ▼]

"Green nails" or chloronychia is an infection mostly caused by Pseudomonas ueruginosa but also by other bacterial or fungal contamination. The clinical appearance consists in a typical triad: green discoloration of the nail plate associated with proximal chronic paronychia and disto-lateral onycholysis. Exposition to moist environment, microtraumatisms, oaychotillomania and associated nail diseases such as psoriasis may promote infection by Pseudomonas. Treatment consists in cutting of the detached nail plate, brushing the nail bed with a 2% sodium hypochlorite solution twice daily and eviction of the repeated immersions by wearing cotton and latex gloves. [less ▲]

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See detailBiometry and paleoenvironment of Retispora lepidophyta (Kedo) Playford 1976 and associated miospores in the latest Famennian nearshore marine facies, eastern Ardenne (Belgium)
Maziane, N.; Higgs, K. T.; Streel, Maurice ULg

in Review of Palaeobotany and Palynology (2002), 118(1-avr Sp. Iss. SI), 211-226

The size diameter of Retispora lepidophyta, a stratigraphically important miospore, is reexamined in greater detail than in previous studies using three sections of the latest Famennian nearshore marine ... [more ▼]

The size diameter of Retispora lepidophyta, a stratigraphically important miospore, is reexamined in greater detail than in previous studies using three sections of the latest Famennian nearshore marine facies of the eastern Ardenne. The evolutionary character of the size reduction with time is confirmed and is used for accurate correlations between the three sections. Cluster analyses (dendrograms) are performed on the percentages of a selection of miospore species from the two most complete sections and show a clear analogy in the lateral distribution of R. lepidophyta and Vallatisporites hystricosus, a species known elsewhere (West Virginia, USA) to belong to coastal 'downstream' near-swamp plant communities [Streel and Scheckler, Rev. Palaeobot. Palynol. 64 (1990) 315-324]. By comparison also with the West Virginia data, three Diducites species are believed to represent the 'coal' swamp vegetation. A decrease in the proportion of the Diducites species from the lower to the upper portion of the studied sections is observed. Using biometric analysis, high resolution correlation between these sections reveals a lateral shift of facies with time during the latest Famennian in the eastern Ardenne. Local synsedimentary block-faulting processes were probably responsible. (C) 2002 Elsevier Science B.V. All rights reserved. [less ▲]

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See detailEpstein-Barr virus in Hodgkin's disease: the example of central Tunisia
Korbi, S.; Trimeche, M.; Sriha, B. et al

in Annales de Pathologie (2002), 22(2), 96-101

The purpose of this study was to evaluate the prevalence of Epstein-Barr virus in Hodgkin disease in Tunisia through a series of 77 cases. Association with Epstein-Barr virus was demonstrated by Epstein ... [more ▼]

The purpose of this study was to evaluate the prevalence of Epstein-Barr virus in Hodgkin disease in Tunisia through a series of 77 cases. Association with Epstein-Barr virus was demonstrated by Epstein-Barr encoded early RNA transcripts (EBER) in situ hybridization in 70 % of cases and by latent membrane protein I (LMPI) immunohistochemistry in 58.4 % of cases. EBER positive cases were more frequent in extreme age clashes (< 15 and > 54 years) there was no correlation with sex, histologic sub-type and clinical stage. Our findings show a high prevalence for EBV infection in Tunisian Hodgkin's disease particularly among extreme ages. [less ▲]

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See detailEtude electromyographique paravertebrale dorso-lombaire. Analyse en mode multi-MUP et etablissement de normes au sein d'une population de reference
Tomasella, Marco ULg; Crielaard, Jean-Michel ULg; WANG, François-Charles ULg

in Neurophysiologie Clinique = Clinical Neurophysiology (2002), 32(2), 109-17

OBJECTIVE: The aim of this study was to contribute to draw up reference values relating to electromyographic (EMG) parameters in dorsal and lumbar paraspinal muscles. MATERIALS AND METHODS: 75 healthy ... [more ▼]

OBJECTIVE: The aim of this study was to contribute to draw up reference values relating to electromyographic (EMG) parameters in dorsal and lumbar paraspinal muscles. MATERIALS AND METHODS: 75 healthy subjects without back pain underwent electromyography of multifidus bundles, which are innervated uni-segmentally by the dorsal ram of the spinal nerve. T8, L3, L4, L5 and S1 myotomes were systematically explored. Output variables were spontaneous denervation activity and quantitative EMG data obtained by multi-MUP (Motor Unit action Potential) analysis. RESULTS: No abnormal insertional or spontaneous activity (such as fibrillation, positive sharp waves or fasciculation) was recorded at rest. Neither sex nor age influenced motor unit action potential features in our series. Reference values were drawn up for T8 and L5 segmental levels using the mean values of 20 motor unit potentials in each patient studied, the reference interval being defined by the lower and the upper outlier limits on individual values. CONCLUSION: This study offers reference data to electromyographers to help better identifying possible myogenic or neurogenic pathological changes, especially in lumbosacral radiculopathies. [less ▲]

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See detailQualité de la prise en charge de l'hypertension artérielle. Pouvons-nous, devons-nous faire mieux?
Krzesinski, Jean-Marie ULg

in Revue Médicale de Liège (2002), 57(4), 202-206

Hypertension is well controlled in only less than 30% of the patients treated by drugs. It is thus important to improve this situation first by checking the treatment compliance but also by trying to ... [more ▼]

Hypertension is well controlled in only less than 30% of the patients treated by drugs. It is thus important to improve this situation first by checking the treatment compliance but also by trying to better educate the hypertensive population about the risk of uncontrolled hypertension and how to decrease this risk. [less ▲]

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See detailEffect of biologically active coating on biocompatibility of Nitinol devices designed for the closure of intra-atrial communications.
Kong, Xiangqing; Grabitz, R. G.; van Oeveren, W. et al

in Biomaterials (2002), 23(8), 1775-83

Anti-thrombogenicity and rapid endothelialisation are prerequisites for the use of closure devices of intra-atrial communications in order to reduce the risk of cerebral embolism. The purpose of this ... [more ▼]

Anti-thrombogenicity and rapid endothelialisation are prerequisites for the use of closure devices of intra-atrial communications in order to reduce the risk of cerebral embolism. The purpose of this study was therefore to assess the effect of bioactive coatings on biocompatibility of Nitinol coils designed for the closure of intra-atrial communications. Nitinol coils (n = 10, each) and flat Nitinol bands (n = 3, each) were treated by basic coating with poly(amino-p-xylylene-co-p-xylylene) and then coated with either heparin, r-hirudin or fibronectin. Anti-thrombogenicity was studied in vitro in a dynamic model with whole blood by partial thromboplastin time (PTT), platelet binding and thrombin generation, respectively, and cytotoxicity by hemolysis. Endothelialisation was studied on Nitinol bands with human umbilical venous endothelial cells (HUVEC) by 3-(4,5-dimethylthiazole-2yl)-2,5-triphenyl tetrazolium (MTT) assay and immnuofluorescence analysis of Ki67, vinculin, fibronectin and von Willebrand Factor. Uncoated or coated devices did not influence hemolysis and PTT. r-Hirudin (but not heparin) and fibronectin coating showed lower platelet binding than uncoated Nitinol (p < 0.005, respectively). Heparin and r-hirudin coating reduced thrombin formation (p < 0.05 versus Nitinol, respectively). HUVEC adhesion, proliferation, and matrix formation decreased in the order: fibronectin coating > uncoated Nitinol > r-hirudin coating > heparin coating > basic coating. MTT assay corroborated these findings. In conclusion, r-hirudin and fibronectin coating, by causing no acute cytotoxicity, decreasing thrombogenicity and increasing endothelialisation improve in vitro biocompatibility of Nitinol devices designed for the closure of intra-atrial communications. [less ▲]

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See detailUse of PIXE-PIGE under variable incident angle for ancient glass corrosion measurements
Weber, Georges ULg; Strivay, David ULg; Martinot, Lucien et al

in Nuclear Instruments & Methods in Physics Research. Section B, Beam Interactions with Materials and Atoms (2002), 189

Although glass is usually considered as a very stable archaeological material, it can undergo severe degradation. Soda-lime glass, the most common glass throughout ancient times, is particularly sensitive ... [more ▼]

Although glass is usually considered as a very stable archaeological material, it can undergo severe degradation. Soda-lime glass, the most common glass throughout ancient times, is particularly sensitive to this problem. The glass surface absorbs moisture from its environment and the contact with CO2 causes Na2O and NaOH to convert to Na2CO3, which is extremely hygroscopic. The subsequent unstable glass layer can be leached out and causes decomposition of the glass. The non-destructive PIGE-PIXE method of investigation allows detection of this phenomenon even if no visible effect appears. The variable incident angle method is able to discern the depth of the degradation. One aim of such studies is the possible dating or at least fake detecting of archaeological materials, Furthermore, even objects of large size can be investigated with the atmospheric PIGE-PIXE Set-LIP, Some examples of measurements on ancient glass are given. (C) 2002 Elsevier Science B.V. All rights reserved. [less ▲]

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See detailMain concepts of the "European approach" to karst-groundwater-vulnerability assessment and mapping
Daly, Donald; Dassargues, Alain ULg; Drew, David et al

in Hydrogeology Journal (2002), 10(2), 340-345

In order to achieve some consistency in the establishment of groundwater intrinsic vulnerability maps in Europe. a new, approach is proposed by Working Group 1 of the European COST Action 620 on ... [more ▼]

In order to achieve some consistency in the establishment of groundwater intrinsic vulnerability maps in Europe. a new, approach is proposed by Working Group 1 of the European COST Action 620 on "Vulnerability mapping for the protection of carbonate (karst) aquifers". A general procedure is offered which provides consistency while allowing the required flexibility for application to a continent and under conditions of varying geology, scale, information availability, time, and resources. The proposed methodology is designed to be clearly more physically based than the existing vulnerability-mapping techniques. It takes the specificity of the karstic environments into account without necessarily excluding the applicability to other geological conditions. Combined "core factors" for overlying layers and for concentration of flow, account for the relative protection of groundwater from contamination while taking into account any bypass of the overlying layers. A precipitation factor is distinguished for describing: characteristics of the input of water to the system. Differentiation is made between groundwater resource intrinsic vulnerability Mapping and Source intrinsic vulnerability mapping. For the latter, a factor describing the karst network development is relevant. This short technical note describes a first stop in the work program of Working Group 1 of the COST Action 620. Future steps are now in progress to quantify the approach and to apply it in various European pilot areas. [less ▲]

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See detailShort- and long-term effects of p-ethynylphenylalanine on brain serotonin levels
Zimmer, Luc; Luxen, André ULg; Giacomelli, Fabrice ULg et al

in Neurochemical Research (2002), 27(4), 269-275

Changes in tissue and extracellular serotonin (5-HT) in raphe dorsalis, raphe medialis and in their main projections areas (hippocampus, striatum and frontal cortex) were investigated at short and long ... [more ▼]

Changes in tissue and extracellular serotonin (5-HT) in raphe dorsalis, raphe medialis and in their main projections areas (hippocampus, striatum and frontal cortex) were investigated at short and long-term times after single injection (5 mg/kg ip) of a novel tryptophan hydroxylase inhibitor, p-ethynylphenylalanine (p-EPA). The 5-HT tissue concentration decreased significantly in raphe nuclei, 30 min post-injection and for 4 days, whereas it decreased from 24 hours post-injection in the 5-HT projections. Normal 5-HT levels reappeared after 12 days post-injection in all areas. Moreover, in the projection areas, the extracellular 5-HT levels decreased rapidly, 90, 40 and 30 min after p-EPA injection, in hippocampus, striatum and frontal cortex, respectively. Decreased accumulation of 5-hydroxytryptophan (5-HTP) under NSD-101 perfusion in the serotoninergic projections after p-EPA injection, confirmed the direct inhibitory effect of the drug on the tryptophan hydroxylase activity. These results demonstrated that p-EPA is a useful pharmacological tool which powerfully, acutely and irreversibly reduces the 5-HT levels. [less ▲]

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See detailMossbauer spectral evidence for next-nearest neighbor interactions within the alluaudite structure of Na1-xLixMnFe2(PO4)(3)
Hermann, Raphaël ULg; Hatert, Frédéric ULg; Fransolet, André-Mathieu ULg et al

in Solid State Sciences (2002), 4(4), 507-513

The Mossbauer spectra of the Na1-xLixMnFe2(PO4)(3) compounds, with x = 0,00, 0.25, 0.50, and 0.75, have been measured between 90 and 295 K and analyzed in terms of a model which takes into account the ... [more ▼]

The Mossbauer spectra of the Na1-xLixMnFe2(PO4)(3) compounds, with x = 0,00, 0.25, 0.50, and 0.75, have been measured between 90 and 295 K and analyzed in terms of a model which takes into account the next-nearest neighbor interactions within the alluaudite structure. Surprisingly, the spectra reveal an unexpected presence of iron(II) in these compounds; the amount of iron(II) is observed to decrease from 19 to 15 atomic percent of the total iron content with increasing x. The temperature dependence of the Fe2+ and Fe3+ isomer shifts agrees with that expected from a second-order Doppler shift and the resulting iron vibrating masses and Mossbauer lattice temperatures are within the expected range of values for iron cations in an octahedral environment. The temperature dependence of the Fe2+ quadrupole splitting has been fit with the Ingalls' model and the results yield a ground state orbital splitting of ca. 500 cm(-1) for the iron(II) sites. The compositional dependence of the isomer shifts and Fe2+ content can be understood in terms of a decrease in the unit-cell volume with increasing substitution of sodium by lithium, a substitution which does not influence the observed quadrupole splittings. (C) 2002 Editions scientifiques et medicales Elsevier SAS. All rights reserved. [less ▲]

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See detailMetabolism of human articular chondrocytes cultured in alginate beads. Longterm effects of interleukin 1 beta and nonsteroidal antiinflammatory drugs
Sanchez, Christelle ULg; Mateus, Marguarita; Defresne, Marie-Paule ULg et al

in Journal of Rheumatology (2002), 29(4), 772-782

OBJECTIVES: To investigate the longterm effects (12 days) of nonsteroidal antiinflammatory drugs [NSAID: aceclofenac (ACECLO), sodium diclofenac (DICLO), indomethacin (INDO), nimesulide (NIM), rofecoxib ... [more ▼]

OBJECTIVES: To investigate the longterm effects (12 days) of nonsteroidal antiinflammatory drugs [NSAID: aceclofenac (ACECLO), sodium diclofenac (DICLO), indomethacin (INDO), nimesulide (NIM), rofecoxib (ROFE), celecoxib (CELE), piroxicam (PIROX), and ibuprofen (IBUP)] on the metabolism of human chondrocytes cultured in alginate beads. METHODS: Enzymatically isolated osteoarthritic (OA) chondrocytes were cultured in alginate beads in a well defined culture medium for 12 days. The DNA content was measured according to a fluorimetric method and cell proliferation was determined by the incorporation of 3H-thymidine in the newly synthesized DNA. Interleukin 6 (IL-6) and IL-8, stromelysin [matrix metalloproteinase-3 (MMP-3)], and aggrecan (AGG) production were assayed by specific enzyme amplified sensitivity immunoassays, and prostaglandin E2 (PGE2) production by specific radioimmunoassay. All NSAID were tested at the mean peak plasma concentration (Cmax) obtained after oral administration of a therapeutic dose. RESULTS: In alginate beads, chondrocytes synthesized high amounts of AGG, which were largely (98%) immobilized in the alginate matrix. A large amount (43%) of the IL-8 produced was stored in the alginate beads, whereas almost all IL-6 production (94%) was released in the culture supernatant. At the therapeutic concentration, all NSAID tested fully blocked PGE2 production. ACECLO, DICLO, INDO, NIM significantly inhibited basal and IL-1beta stimulated IL-6 production; CELE and IBUP only inhibited IL-1beta stimulated IL-6 production; and ROFE and PIROX had no significant effects. No NSAID showed significant effects on basal and IL-1beta stimulated IL-8 production, except CELE and IBUP, which slightly increased basal IL-8 production. ACECLO and INDO increased AGG content by 25% in the alginate beads, while the other NSAID were without significant effect. No NSAID were able to modify the inhibitory effect of IL-1beta on AGG production. NSAID did not modify MMP-3 production. CONCLUSION: The mechanism of action of NSAID seems to be multifactorial and not limited to the inhibition of cyclooxygenases. Further, in our culture conditions, at the Cmax and by comparison with other NSAID, ACECLO and INDO show an advantageous activity profile. They fully blocked PGE2 production, inhibited IL-6 synthesis, and increased aggrecan synthesis. These effects appear advantageous for the longterm treatment of chronic joint diseases such as osteoarthritis. [less ▲]

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See detailAntegrade palliation for diminutive pulmonary arteries in Tetralogy of Fallot.
Seipelt, Ralf G; Vazquez-Jimenez, Jaime F; Sachweh, Jorg S et al

in European Journal of Cardio - Thoracic Surgery (2002), 21(4), 721-4724

OBJECTIVES: The purpose of this study was to evaluate the outcome following palliative reconstruction of right ventricular outflow tract in Tetralogy of Fallot (TOF) with diminutive pulmonary arteries ... [more ▼]

OBJECTIVES: The purpose of this study was to evaluate the outcome following palliative reconstruction of right ventricular outflow tract in Tetralogy of Fallot (TOF) with diminutive pulmonary arteries with central and peripheral stenosis. METHODS: Between 1986 and 1999 in 15 children with the diagnosis of TOF palliative reconstruction of the right ventricular outflow tract without closure of the ventricular septal defect (VSD) was performed. All patients were not suitable for an AP-Shunt because of a diminutive pulmonary vascular bed. Six patients were younger than 1 year at operation. RESULTS: There was one hospital death (6.7%) in a child with additional aortic valve insufficiency in multi-organ failure. Although the postoperative course was prolonged (median duration on ICU: 8 days) and complicated by congestive heart failure, clinically the 14 patients discharged improved significantly. The arterial oxygen saturation increased from 67 to 93% (P<0.001), the hemoglobin decreased from 16.1 to 13.3g/l (P=0.02) and hematocrit from 0.52 to 0.40 (P=0.06). In control angiography, the McGoon Index increased in the average from 1.01 to 1.95 (P<0.001). VSD closure was performed in 12 patients (median: 2.5 years after initial operation) with one perioperative death. A homograft had to be implanted in seven patients and a mechanical prosthesis in the right ventricular outflow tract in one. One late death occurred due to ventricular arrhythmia 12 years after antegrade palliation (11 years after corrective operation). CONCLUSIONS: The antegrade palliation seems to be an adequate strategy for the treatment of selected children with diminutive pulmonary arteries in TOF, who were not candidates for primary correction or an AP-Shunt. [less ▲]

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See detailDetermination of the singlet oxygen quantum yield of bacteriochlorin a: a comparative study in phosphate buffer and aqueous dispersion of dimiristoyl-L-a-phosphatidylcholine liposomes
Hoebeke, Maryse ULg; Damoiseau, Xavier

in Photochemical & Photobiological Sciences (2002), 1(4), 283-287

The production of singlet oxygen (1O2) by bacteriochlorin a (BCA) was studied in phosphate buffer and in dimyristoyl-L-α-phosphatidylcholine (DMPC) unilamellar liposomes. The comparative method used to ... [more ▼]

The production of singlet oxygen (1O2) by bacteriochlorin a (BCA) was studied in phosphate buffer and in dimyristoyl-L-α-phosphatidylcholine (DMPC) unilamellar liposomes. The comparative method used to measure 1O2 production was a quantitative analysis of photooxidation reactions leading to the loss of absorbance of the water-soluble specific probe: anthracene 9,10-dipropionic acid. Rose Bengal, whose 1O2 quantum yield (ΦRB) is well known in alcohols and phosphate buffer, was used as the standard for the quantification of the BCA singlet oxygen production. Our results confirm quantitatively that solubilization of BCA in liposomes leads to an increase in 1O2 production. Indeed, the quantum yield of 1O2 production by BCA (ΦBCA) is 0.05 in phosphate buffer and 0.33 in DMPC liposomes. Furthermore, the diffusion characteristics of 1O2 produced by BCA bound to liposome were also examined using the isotopic lifetime enhancement effect of D2O. It was shown that 1O2 spent at least 70% of its lifetime in the vesicular environment [less ▲]

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See detailDefense of the bovine mammary gland by polymorphonuclear neutrophil leukocytes
Paape, Max; Mehrzad, Jalil; Zhao, Xin et al

in Journal of Mammary Gland Biology and Neoplasia (2002), 7(2), 109-121

The primary phagocytic cells of the bovine mammary gland, polymorphonuclear neutrophil leukocytes (PMN), and macrophages, comprise the first line of defense against invading pathogens. In the normal ... [more ▼]

The primary phagocytic cells of the bovine mammary gland, polymorphonuclear neutrophil leukocytes (PMN), and macrophages, comprise the first line of defense against invading pathogens. In the normal healthy mammary gland, macrophages predominate and act as sentinels to invading mastitis-causing pathogens. Once invaders are detected, macrophages, and possibly mammary epithelial cells, release chemoattractants that direct migration of PMN into the area. In the mammary gland, protection is only effective if rapid influx of PMN from the circulation and subsequent phagocytosis and killing of bacteria occur. The second line of defense against infection consists of a network of memory cells and immunoglobulins that interact with the first line of defense. To minimize mammary tissue damage caused by bacterial toxins and oxidative products released by PMN, elimination of invading bacteria must proceed quickly. Therefore, the inflammatory response needs to be regulated. Hormones, metabolites, and acute phase proteins act to influence the outcome of mastitis, especially around parturition. The number of circulating PMN in cows during early lactation is highly heritable and closely related to susceptibility to clinical mastitis at this time. Advances in molecular biology are making available the tools, techniques, and products to study and modulate host-pathogen interactions. For example, the cloning and expression of proteins such as recombinant bovine soluble (rbos) CD (cluster of differentiation) 14 antigens, may provide ways of minimizing damaging effects of endotoxin during acute coliform mastitis. Soluble CD14 binds and neutralizes lipopolysacharide (LPS) and causes local recruitment of PMN after binding of CD14-LPS complexes to mammary epithelial cells. Development of transgenic animals that express rbosCD14 in their milk could prevent infection by Gram-negative pathogens. [less ▲]

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See detailClinique et cytologie sputaire de l'asthme intrinseque
Bettiol, J.; Radermecker, Maurice ULg; Louis, Renaud ULg

in Revue Médicale de Liège (2002), 57(4), 223-7

The diagnosis of intrinsic asthma is evoked in patients with clinical criteria of asthma but, who contrarily to atopic asthmatics, lack history of allergy, specific IgE and skin positive reaction towards ... [more ▼]

The diagnosis of intrinsic asthma is evoked in patients with clinical criteria of asthma but, who contrarily to atopic asthmatics, lack history of allergy, specific IgE and skin positive reaction towards common aeroallergens of the environment. While the bronchial cytology of these two types of asthma is comparable, the immunological mechanisms of intrinsic asthma remain poorly understood because the factors responsible for the bronchial inflammation are unknown. Intrinsic asthma normally begins in adulthood and carries often a more severe prognosis. This disease is more frequent in women and is often associated to nasal polyposis and/or aspirin hypersensitivity. In this work, we have retrospectively studied the demographic and clinical characteristics, as well as the lung function and the sputum cell counts of intrinsic asthmatic outpatients seen during the period of 1996 to 1998 in the Pneumology Department of the CHU Sart Tilman. [less ▲]

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See detailMeasurement of lifetimes by laser-induced fluorescence and determination of transition probabilities of astrophysical interest in NdIII
Zhang, Z. G.; Svanberg, S.; Palmeri, P. et al

in Astronomy and Astrophysics (2002), 385(2), 724-732

Selective lifetime measurements by time-resolved laser-induced fluorescence spectroscopy for 5 levels belonging to the 4f(3)5d configuration of doubly ionized neodymium provide a first and useful ... [more ▼]

Selective lifetime measurements by time-resolved laser-induced fluorescence spectroscopy for 5 levels belonging to the 4f(3)5d configuration of doubly ionized neodymium provide a first and useful experimental test of the relativistic Hartree-Fock calculations in this ion of astrophysical interest. As a consequence, the accuracy of the transition probabilities deduced in the present work is well assessed. These new data are expected to help astrophysicists in the future to refine the analysis of the composition of chemically peculiar stars which frequently show large overabundances of lanthanides when compared to the solar system standards. [less ▲]

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See detailLe point de vue documentaire dans Le joli mai de Chris Marker
Van Cauwenberge, Geneviève ULg

in Théorème (2002), (6), 83-99

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See detailRemarkable conservation of internally transcribed spacer sequences of Arthrospira ("Spirulina") (Cyanophyceae, Cyanobacteria) strains from four continents and of recent and 30-year-old dried samples from Africa
Baurain, Denis ULg; Renquin, Laurent; Grubisic, Stana ULg et al

in Journal of Phycology (2002), 38(2), 384-393

The internally transcribed spacer (ITS) sequences of 21 Arthrospira clonal strains from four continents and assigned to four different species (A. platensis, A. maxima, A. fusiformis, A. indica) in the ... [more ▼]

The internally transcribed spacer (ITS) sequences of 21 Arthrospira clonal strains from four continents and assigned to four different species (A. platensis, A. maxima, A. fusiformis, A. indica) in the culture collections were determined. Two main clusters, I and H, were differentiated by 49 positions out of 475 nt or 477 nt, respectively. Each cluster was further subdivided into two subclusters. Subclusters LA and I.B were separated by two substitutions, whereas subclusters II.A, and II.B were distinguished by four substitutions. After direct sequencing of the PCR products, three dried samples from Chad aged between 3 months and 35 years yielded a sequence belonging to subcluster I.A, as did a recent commercial product. The strains grown in production plants belonged to the same (sub)clusters as strains from culture collections, mainly LA and II. PCR primers specific for each cluster and subcluster were designed and tested with crude cell lysates of Arthrospira strains. One dried sample ("dihe' 1) and a herbarium sample from Lake Sonachi (Kenya) only contained I.A sequences, whereas the commercial product was a mixture of the four genotypes and the other two dried samples contained minor polymorphisms characteristic of different clusters. Five clonal Arthrospira strains, thought to be duplicates, showed the simultaneous presence of the two :Forms of the four diagnostic positions that distinguish subclusters genotype H.A and genotype II.B. This is likely to be caused by multiple copies of the rDNA operon, in a intermediate stage of homogenization between subcluster II.A and subcluster II.B. The high conservation of ITS sequences is in contrast with the assignment to four different species, the great morphological variability of the strains, and their wide geographic distribution. [less ▲]

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See detailDemonstration of generalized infection with caprine herpesvirus 1 diagnosed in an aborted caprine fetus by PCR
Keuser, V.; Gogev, S.; Schynts, F. et al

in Veterinary Research Communications (2002), 26(3), 221-226

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See detailFull-scale tests of torsional damper and detuner (TDD) antigalloping device
Lilien, Jean-Louis ULg; Vinogradov, Alexander

in IEEE Transactions on Power Delivery (2002), 17(2), 638-643

A new antigalloping device for overhead lines with bundle conductors was introduced ten years ago, after laboratory tests and observations on actual 400-kV lines. A systematic fullscale test was performed ... [more ▼]

A new antigalloping device for overhead lines with bundle conductors was introduced ten years ago, after laboratory tests and observations on actual 400-kV lines. A systematic fullscale test was performed in Kazakhstan in order to better evaluate torsional damper and detuner (TDD) efficiency. This report details the test station and the results obtained over a several month period of testing and measurement. The tests were carried out thanks to the mutual efforts of the ESSP and the Kazakh Power Research Institute (KazNIIE) at the field tests stand located in Chokpar. [less ▲]

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See detailEvaluation of thermodynamic properties of concrete substrates and cement slurries modified with admixtures
Courard, Luc ULg

in Materials and Structures (2002), 35(247), 149-155

The study of the creation and the stability of the interface between concrete substrates and repair systems needs the knowledge of the thermodynamic properties of materials. The measurement of the surface ... [more ▼]

The study of the creation and the stability of the interface between concrete substrates and repair systems needs the knowledge of the thermodynamic properties of materials. The measurement of the surface free energies of liquids is realised by means of Wilhelmy plate method on reference liquid and repair products. In order to determine polar and dispersive components, it is necessary to measure the contact angle of these liquids and products on reference solid surfaces and on concrete, mortars and aggregates. Centrifuged solutions of repair product systems elements were prepared in order to measure surface free energies on pure liquids without solid particles in suspension. Evolution of properties versus time were also taken into account and analysed in comparison with well-known liquids and products. [less ▲]

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See detailLa cardiologie preventive: strategies chez l'enfant
Massin, M.; Vandoorne, Chantal ULg; Coremans, C. et al

in Revue Médicale de Liège (2002), 57(4), 207-12

The importance of preventive cardiology in youth has been established by several critical observations: there is evidence that the atherogenic process begins in childhood, and that the degree of ... [more ▼]

The importance of preventive cardiology in youth has been established by several critical observations: there is evidence that the atherogenic process begins in childhood, and that the degree of atherogenesis is related to measurable risk factors present during childhood. The literature indicated that long-range prevention of atheroselerosis and its sequelae by control of those risk factors should begin in childhood. This article reviews the established risk factors, the identification of high-risk individuals, public health strategies for the promotion of health in the French Community of Belgium and treatment of high-risk individuals. [less ▲]

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See detailFunctional glycine receptors are expressed by postnatal nestin-positive neural stem/progenitor cells
Nguyen, Laurent ULg; Malgrange, Brigitte ULg; Belachew, Shibeshih ULg et al

in European Journal of Neuroscience (2002), 15(8), 1299-1305

Multipotent neural stem and progenitor cells (NS/PCs) are well-established cell subpopulations occurring in the developing, and also in the mature mammalian nervous systems. Trophic and transcription ... [more ▼]

Multipotent neural stem and progenitor cells (NS/PCs) are well-established cell subpopulations occurring in the developing, and also in the mature mammalian nervous systems. Trophic and transcription factors are currently the main signals known to influence the development and the commitment of NS/PCs and their progeny. However, recent studies suggest that neurotransmitters could also contribute to neural development. In that respect, rodent-cultured embryonic NS/PCs have been reported to express functional neurotransmitter receptors. No similar investigation has, however, been made in postnatal and/or in adult rodent brain stem cells. In this study, using RT-PCR and immunocytochemical methods, we show that alpha(1) -, alpha(2) - and beta-subunit mRNAs and alpha-subunit proteins of the glycine ionotropic receptor are expressed by 80.5 +/- 0.9% of postnatal rat striatum-derived, nestin-positive cells within cultured neurospheres. Whole-cell patch-clamp experiments further demonstrated that glycine triggers in 33.5% of these cells currents that can be reversibly blocked by strychnine and picrotoxin. This demonstrates that NS/PCs express functional glycine receptors, the consequence(s) of their activation remaining unknown. [less ▲]

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See detailComparison of different impulse response measurement techniques
Stan, Guy-Bart; Embrechts, Jean-Jacques ULg; Archambeau, Dominique

in Journal of the Audio Engineering Society (2002), 50(4), 249-262

The impulse response of an acoustical space or transducer is one of its most important characterizations. In order to perform the measurement of their impulse responses, four of the most suitable methods ... [more ▼]

The impulse response of an acoustical space or transducer is one of its most important characterizations. In order to perform the measurement of their impulse responses, four of the most suitable methods are compared: MLS (maximum-length sequence), IRS (inverse repeated sequence), time-stretched pulses, and SineSweep. These methods have already been described in the literature. Nevertheless, the choice of one of them depending on the measurement conditions is critical. Therefore an extensive comparison has been realized. This comparison was done through the implementation and realization of a complete, fast, reliable, and cheap measurement system. Finally, a conclusion for the use of each method according to the principal measurement conditions is presented. It is shown that in the presence of nonwhite noise, the MLS and IRS techniques seem to be more accurate. On the contrary, in quiet environments the logarithmic SineSweep method seems to be the most appropriate. [less ▲]

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See detailModulation of adipose tissue expression of murine matrix metalloproteinases and their tissue inhibitors with obesity
Maquoi, Erik ULg; Munaut, Carine ULg; Colige, Alain ULg et al

in Diabetes (2002), 51(4), 1093-1101

The potential role of the matrix metalloproteinase (MMP) system in the pathophysiology of the adipose tissue was investigated in a mouse model of nutritionally induced obesity. mRNA levels of 16 MMPs and ... [more ▼]

The potential role of the matrix metalloproteinase (MMP) system in the pathophysiology of the adipose tissue was investigated in a mouse model of nutritionally induced obesity. mRNA levels of 16 MMPs and 4 tissue inhibitors of MMPs (TIMPs) were measured by semiquantitative RT-PCR in adipose tissue isolated from mice maintained for 15 weeks on a standard or high-fat diet. In mice on standard diet, with the exception of MMP-8, all MMP and TIMP transcripts were detected in both gonadal and subcutaneous depots. In obese mice, the expression of MMP-3, -11, -12, -13, and -14 and TIMP-1 mRNAs was upregulated, whereas that of MMP-7, -9, -16, and -24 and TIMP-4 was downregulated. Most MMP and TIMP mRNAs were expressed at higher levels in stromal-vascular cells than in mature adipocytes. Analysis of adipose tissue by in situ fluorescent zymography revealed MMP-dependent proteolytic activities, demonstrating the presence of active MMPs in the intact tissue. In vitro conversion of adipogenic 3T3-F442A cells into mature adipocytes was associated with substantial modulations of MMP and TIMP expression. Moreover, this in vitro adipogenesis was reduced in the presence of a synthetic MMP inhibitor. Thus, the adipose tissue expresses a large array of MMPs and TIMPs, which modulate adipocyte differentiation. [less ▲]

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See detailMT1-MMP expression promotes tumor growth and angiogenesis through an up-regulation of vascular endothelial growth factor expression
Sounni, Nor Eddine ULg; Devy, L.; Hajitou, A. et al

in FASEB Journal (2002), 16(6), 555-564

Membrane type 1 metalloprotease (MT1-MMP) is a transmembrane metalloprotease that plays a major role in the extracellular matrix remodeling, directly by degrading several of its components and indirectly ... [more ▼]

Membrane type 1 metalloprotease (MT1-MMP) is a transmembrane metalloprotease that plays a major role in the extracellular matrix remodeling, directly by degrading several of its components and indirectly by activating pro-MMP2. We investigated the effects of MT1-MMP overexpression on in vitro and in vivo properties of human breast adenocarcinoma MCF7 cells, which do not express MT1-MMP or MMP-2. MT1-MMP and MMP-2 cDNAs were either transfected alone or cotransfected. All clones overexpressing MT1-MMP 1) were able to activate endogenous or exogenous pro-MMP-2, 2) displayed an enhanced in vitro invasiveness through matrigel-coated filters independent of MMP-2 transfection, 3) induced the rapid development of highly vascularized tumors when injected subcutaneously in nude mice, and 4) promoted blood vessels sprouting in the rat aortic ring assay. These effects were observed in all clones overexpressing MT1-MMP regardless of MMP-2 expression levels, suggesting that the production of MMP-2 by tumor cells themselves does not play a critical role in these events. The angiogenic phenotype of MT1-MMP-producing cells was associated with an up-regulation of VEGF expression. These results emphasize the importance of MT1-MMP during tumor angiogenesis and open new opportunities for the development of anti-angiogenic strategies combining inhibitors of MT1-MMP and VEGF antagonists. [less ▲]

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See detailThe prevalence and burden of arthritis
Reginster, Jean-Yves ULg

in Rheumatology (2002), 41(Suppl. 1), 3-7

The prevalence of arthritis is high, with osteoarthritis (OA) being one of the most frequent disorders in the population. In England and Wales, between 1.3 and 1.75 million people have OA and a further 0 ... [more ▼]

The prevalence of arthritis is high, with osteoarthritis (OA) being one of the most frequent disorders in the population. In England and Wales, between 1.3 and 1.75 million people have OA and a further 0.25 0.5 million have rheumatoid arthritis (RA), while in France some 6 million new diagnoses of OA Lire made each year. In 1997, similar to16%, of the US population had some form of arthritis. This prevalence is expected to increase in the coining years, as arthritis more often affects the elderly, a proportion of the population that is increasing. The economic burden of such musculoskeletal diseases is also high, accounting for up to 1-2.5%, of the gross national product of western nations. This burden comprises both the direct costs of medical interventions and indirect costs, such as premature mortality and chronic and short-term disability. The impact of arthritis on quality of life is of particular importance. Musculoskeletal disorders are associated with some of the poorest quality-of-life issues, particularly in terms of bodily pain (mean score from the MOS 36-item Short Form Health Survey of 52.1) and physical functioning (49.9), where quality of life is lower than that for gastrointestinal conditions (bodily pain 52.9, physical functioning 55.4), chronic respiratory diseases (72.7, 65.4) and cardiovascular conditions (64.7, 59.3). [less ▲]

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See detailPolyethylene-layered silicate nanocomposites prepared by the polymerization-filling technique: synthesis and mechanical properties
Alexandre, Michaël ULg; Dubois, Philippe ULg; Sun, Tao et al

in Polymer (2002), 43(8), 2123-2132

Polyethylene-layered silicate nanocomposites were prepared by the in situ intercalative polymerization of ethylene by the so-called polymerization-filling technique and analyzed by transmission electron ... [more ▼]

Polyethylene-layered silicate nanocomposites were prepared by the in situ intercalative polymerization of ethylene by the so-called polymerization-filling technique and analyzed by transmission electron microscopy (TEM), X-ray diffraction analysis (XRD), differential scanning calorimetry, dynamic mechanical analysis and tensile testing. Non-modified montmorillonite and hectorite were first treated by trimethylaluminum-depleted methylaluminoxane before being contacted by a Ti-based constrained geometry catalyst. The nanocomposite was formed by addition and polymerization of ethylene. In the absence of a chain transfer agent, ultra high molecular weight polyethylene was produced. The tensile properties of these nanocomposites were poor and essentially independent of the nature and content of the silicate. Upon hydrogen addition, the molecular weight of the polyethylene was decreased with parallel improvement of the tensile and shear moduli, in relation to the filler content. The exfoliation of the layered silicates was confirmed by XRD analysis and TEM observation. The mechanical kneading of the molten nanocomposites resulted in the partial collapse of the exfoliated structure driven by the thermodynamic stability of the layered filler. [less ▲]

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See detailEncephalitis related to primary varicella-zoster virus infection in immunocompetent children.
Hausler, M.; Schaade, L.; Kemeny, S. et al

in Journal of the neurological sciences (2002), 195(2), 111-6

INTRODUCTION: Encephalitis is a rare complication of primary varicella-zoster virus (VZV) infection in immunocompetent children. METHODS: The clinical and laboratory findings of two girls with VZV-related ... [more ▼]

INTRODUCTION: Encephalitis is a rare complication of primary varicella-zoster virus (VZV) infection in immunocompetent children. METHODS: The clinical and laboratory findings of two girls with VZV-related encephalitis are reported. RESULTS: Both children presented with focal epileptic seizures, corresponding to cortical/subcortical as well as white matter lesions. The first showed a typical vesicular skin rash. She was easily diagnosed and made a rapid recovery during acyclovir and steroid treatment. In the second girl, a preceding measles-mumps-rubella virus vaccination and the absence of skin vesicles were misleading with respect to the diagnosis, which was finally proven by IgG seroconversion and intrathecal synthesis of IgG antibodies to VZV. She developed left parieto-occipital tissue necrosis and recovered only transiently during initial acyclovir/steroid treatment. Eight weeks after onset, progressive white matter demyelination and the occurrence of erythema nodosum in the lower limbs necessitated a second 4-month course of oral steroids. The VZV PCR from cerebrospinal fluid was negative in both children. CONCLUSIONS: Primary VZV infection may cause severe encephalitis that may occur without skin vesicles and lead to a chronic course with systemic vasculitis. The coincidence of vaccination and neurologic diseases offers no proof per se of a causal relationship. [less ▲]

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See detailCustomization of a self-processing polymer for obtaining specific diffractive optical elements
Carre, C.; Saint-Georges, Philippe ULg; Lenaerts, Cedric ULg et al

in Synthetic Metals (2002), 127

Photopolymerizable materials are capable of recording volume holograms via a change in refractivity of the layer. On illumination by an interference pattern around 500 nm, polymerization and diffusion led ... [more ▼]

Photopolymerizable materials are capable of recording volume holograms via a change in refractivity of the layer. On illumination by an interference pattern around 500 nm, polymerization and diffusion led to regions with various segment densities. A modulation of the refractive index took place, thus giving rise to permanent thick phase gratings created in situ in the emulsion. This modulation was estimated at 7 x 10(-3), corresponding to diffraction efficiencies of ca. 80% for transmission holography. Applications for the fabrication of diffractive optical elements can be expected in view of the experimental results and the simplicity of use. For instance, the duplication of computer-generated holograms on a photopolymerizable film led to thick phase holograms with higher diffraction efficiencies. Substrate-mode polarizing elements were also produced, taking advantage of the laminated property since this emulsion was embedded between two glass plates. (C) 2002 Elsevier Science B.V. All rights reserved. [less ▲]

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See detailSelection of a staggered grid for inertia-gravity waves in shallow water
Beckers, Jean-Marie ULg

in International Journal for Numerical Methods in Fluids (2002), 38(8), 729-746

The problem of accuracy in propagating inertia-gravity waves on Arakawa grids is investigated. It is shown that the sole analysis of spatial discretization and the recommendation of the B-grid for coarse ... [more ▼]

The problem of accuracy in propagating inertia-gravity waves on Arakawa grids is investigated. It is shown that the sole analysis of spatial discretization and the recommendation of the B-grid for coarse resolution models and C-grid for high resolution models must be re-analysed when time discretization is taken into account as well. For a chosen time discretization, a coarse C-grid is shown for example, to increase precision when using larger time-steps (up to the stability limit) whereas the precision of the B-grid decreases. Here, an analysis of error for different grids in function of the space-time resolutions and computational costs is presented and some recommendations on the choice of the particular staggered grid for a given application are outlined. Copyright (C) 2002 John Wiley Sons, Ltd. [less ▲]

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See detailSynthesis, hydrolysis, biochemical and theoretical evaluation of 1,4-bis(alkoxycarbonyl)azetidin-2-ones as potential elastase inhibitors
Gérard, Stéphane; Dive, Georges ULg; Clamot, Brigitte et al

in Tetrahedron (2002), 58(12), 2423-2433

A series of 1,4-bis(alkoxycarbonyl)azetidin-2-ones, designed as potential suicide-inhibitors of serine proteases, has been synthesized and evaluated against porcine pancreatic elastase (PPE). The most ... [more ▼]

A series of 1,4-bis(alkoxycarbonyl)azetidin-2-ones, designed as potential suicide-inhibitors of serine proteases, has been synthesized and evaluated against porcine pancreatic elastase (PPE). The most active compound (K(i)similar to10 muM; reversible inhibitor) was equipped with phenethyloxycarbonyl and benzyloxycarbonyl side-chains at positions N1 and C4, respectively, with the (S)-configuration. H-1 NMR spectroscopic analysis of the reaction mixtures showed that the ester function is preferentially hydrolyzed, in both chemical and enzyme-catalyzed reactions, with regard to the azetidinone and urethane functions. Considering the three potentially sensitive carbonyl functions and the two stereoisomers, ab initio calculations were performed to determine the energetic barriers required to reach the transition state structures of hydrolysis in a model of the enzyme pocket. (C) 2002 Elsevier Science Ltd. All rights reserved. [less ▲]

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See detailLocal structure of liquid GeTe via neutron scattering and ab initio simulations
Raty, Jean-Yves ULg; Godlevsky, V. V.; Gaspard, Jean-Pierre ULg et al

in Physical Review. B, Condensed Matter and Materials Physics (2002), 65

We examine the local atomic order as well as some dynamic properties of the semiconducting liquid GeTe. We employ hot-neutron two-axis diffraction at three temperatures above the melting point and compare ... [more ▼]

We examine the local atomic order as well as some dynamic properties of the semiconducting liquid GeTe. We employ hot-neutron two-axis diffraction at three temperatures above the melting point and compare these results with ab initio molecular dynamics simulations. The simulations were based on interatomic forces derived from pseudopotentials constructed within density functional theory. At the melting temperature, the Peierls distortion responsible for the lower-temperature crystal phase is shown to manifest itself within the liquid structure. At higher temperatures in the liquid, increasing disorder in the Ge environment determines the eventual semiconductor-metal transition. The calculated kinematic viscosity of the liquid is found to agree with the experimental value and is shown to arise from the small diffusion coefficient of the Te atoms. [less ▲]

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See detailControl of proliferation, endoreduplication and differentiation by the Arabidopsis E2Fa-DPa transcription factor
De Veylder, L.; Beeckman, T.; Beemster, G. T. S. et al

in EMBO Journal (2002), 21(6), 1360-1368

New plant cells arise at the meristems, where they divide a few times before they leave the cell-cycle program and start to differentiate. Here we show that the E2Fa-DPa transcription factor of ... [more ▼]

New plant cells arise at the meristems, where they divide a few times before they leave the cell-cycle program and start to differentiate. Here we show that the E2Fa-DPa transcription factor of Arabidopsis thaliana is a key regulator determining the proliferative status of plant cells. Ectopic expression of E2Fa induced sustained cell proliferation in normally differentiated cotyledon and hypocotyl cells. The phenotype was enhanced strongly by the co-expression of E2Fa with its dimerization partner, DPa. In endoreduplicating cells, E2Fa-DPa also caused extra DNA replication that was correlated with transcriptional induction of S phase genes. Because E2Fa-DPa transgenic plants arrested early in development, we argue that controlled exit of the cell cycle is a prerequisite for normal plant development. [less ▲]

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See detailDoubly ionized thorium: Laser lifetime measurements and transition probability determination of interest in cosmochronology
Biémont, Emile ULg; Palmeri, P.; Quinet, Pascal ULg et al

in Astrophysical Journal (2002), 567(2, Part 1), 1276-1283

The first lifetime measurements have been performed for six levels of doubly ionized thorium, an important cosmochronometer in astrophysics for estimating the age of the Galaxy. The levels, belonging to ... [more ▼]

The first lifetime measurements have been performed for six levels of doubly ionized thorium, an important cosmochronometer in astrophysics for estimating the age of the Galaxy. The levels, belonging to the 5f(2), 5f7p, 7s7p, and 6d7p configurations of Th III, have been measured by the time-resolved laser-induced fluorescence method and compared with relativistic Hartree-Fock calculations including configuration interaction and core-polarization effects. Taking advantage of the excellent agreement between theory and experiment, a first set of transition probabilities of astrophysical interest has been deduced for this ion from a combination of the experimental lifetimes and of the theoretical branching fractions. [less ▲]

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See detailStrategy for the development of automated methods involving dialysis and trace enrichment as on-line sample preparation for the determination of basic drugs in plasma by liquid chromatography
Chiap, Patrice ULg; Hubert, Philippe ULg; Crommen, Jacques ULg

in Journal of Chromatography. A (2002), 948(1-2), 151-161

Among the sample preparation techniques, dialysis followed by clean-up and enrichment of the dialysate on a pre-column has proved to be a useful approach for the LC determination of drugs in plasma. By ... [more ▼]

Among the sample preparation techniques, dialysis followed by clean-up and enrichment of the dialysate on a pre-column has proved to be a useful approach for the LC determination of drugs in plasma. By use of sample processors, like the ASTED system, such bioanalytical methods can be fully automated, the dialysis and trace enrichment steps being directly coupled to LC. In order to facilitate the development of such automated methods, a strategy based on a decision tree has been elaborated. After the selection of appropriate conditions for the LC analysis, the decision tree provides information about suggested starting conditions and guidelines for the optimisation of the most important parameters likely to influence analyte recovery and method selectivity. The plasma samples are dialysed on a cellulose acetate membrane in the static-pulsed mode and the dialysate is enriched on a trace enrichment pre-column packed with octadecyl silica or with a strong cation-exchange material. This decision tree is until now restricted to the analysis of basic drugs in plasma. In order to demonstrate the applicability of this method development strategy, an automated procedure based on the coupling of dialysis with trace enrichment has been developed for the LC determination of antifungal agents (clotrimazole, econazole and miconazole) in plasma. (C) 2002 Elsevier Science B.V. All rights reserved. [less ▲]

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See detailMatrix metalloproteinase inhibition impairs adipose tissue development in mice
Lijnen, Roger; Maquoi, Erik ULg; Hansen, L. B. et al

in Arteriosclerosis, Thrombosis, and Vascular Biology (2002), 22(3), 374-379

The effect of galardin, a broad-spectrum matrix metalloproteinase (MMP) inhibitor, was studied in mice kept on a high fat diet (HFD). Five-week-old male wild-type mice were fed the HFD (42% fat) for up to ... [more ▼]

The effect of galardin, a broad-spectrum matrix metalloproteinase (MMP) inhibitor, was studied in mice kept on a high fat diet (HFD). Five-week-old male wild-type mice were fed the HFD (42% fat) for up to 12 weeks and were daily injected intraperitoneally with the inhibitor (100 mg/kg) or with vehicle. After 12 weeks of the HFD, the body weights of both groups were comparable, but the weight of the isolated subcutaneous (SC) or gonadal (GON) fat deposits was significantly lower in the inhibitor-treated group than in the control group (88 +/- 11 versus 251 +/- 66 mg, respectively, for SC fat [P<0.05]; 90 +/- 24 versus 217 +/- 30 mg, respectively, for GON fat [P<0.02]). The number of adipocytes was somewhat higher and the diameter was somewhat smaller (but not significantly) in adipose tissues of the inhibitor-treated group. Adipose tissue of the inhibitor-treated mice contained more collagen than did that of the vehicle-treated mice (Sirius red-stained area of 42 +/- 2.6% versus 22 +/- 4.4%, respectively, for SC fat [P<0.05]; 21 +/- 5.1% versus 4.7 +/- 0.92%, respectively, for GON fat [P<0.01]); a distinct collagen-rich cap was formed around the inhibitor-treated tissue. In situ zymography with casein- or gelatin-containing gels confirmed a reduced MMP activity in SC and GON adipose tissues of inhibitor-treated mice. Thus, in this model, growth and development of adipose tissue appears to be limited by the formation of a collagen-rich matrix cap around the inhibitor-treated tissue. These data suggest a functional role for MMPs in the development of adipose tissue. [less ▲]

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See detailThe tumorigenic diversity of the three PLAG family members is associated with different DNA binding capacities.
Hensen, Karen; Van Valckenborgh, Isabelle C C; Kas, Koen et al

in Cancer Research (2002), 62(5), 1510-7

Pleomorphic adenoma gene (PLAG) 1, the main translocation target in pleomorphic adenomas of the salivary glands, is a member of a new subfamily of zinc finger proteins comprising the tumor suppressor ... [more ▼]

Pleomorphic adenoma gene (PLAG) 1, the main translocation target in pleomorphic adenomas of the salivary glands, is a member of a new subfamily of zinc finger proteins comprising the tumor suppressor candidate PLAG-like1 (also called ZAC1 or lost on transformation 1) and PLAGL2. In this report, we show that NIH3T3 cells overexpressing PLAG1 or PLAGL2 display the typical markers of neoplastic transformation: (a) the cells lose cell-cell contact inhibition; (b) show anchorage-independent growth; and (c) are able to induce tumors in nude mice. In contrast, PLAGL1 has been shown to prevent the proliferation of tumor cells by inducing cell cycle arrest and apoptosis. This difference in function is also reflected in their DNA binding, as we show here that the three PLAG proteins, although highly homologous in their DNA-binding domain, bind different DNA sequences in a distinct fashion. Interestingly, the PLAG1- and PLAGL2-induced transformation is accompanied by a drastic up-regulation of insulin-like growth factor-II, which we prove is a target of PLAG1 and PLAGL2. This strongly suggests that the oncogenic capacity of PLAG1 and PLAGL2 is mediated at least partly by activating the insulin-like growth factor-II mitogenic pathway. [less ▲]

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See detailSplit Comet C/2001 A2 (LINEAR)
Jehin, Emmanuel ULg; Boehnhardt, Hermann; Sekanina, Zdenek et al

in Earth, Moon, and Planets (2002), 90

Comet C/2001 A2 experienced several splitting events during its 2001 perihelion passage. The first break-up event was observed in March 2001 (IAUC 7616). In this paper we report the first results of our ... [more ▼]

Comet C/2001 A2 experienced several splitting events during its 2001 perihelion passage. The first break-up event was observed in March 2001 (IAUC 7616). In this paper we report the first results of our extensive imaging and spectroscopic monitoring campaign with ESO telescopes over several weeks before and after the perihelion passage on May 25 2001. [less ▲]

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See detailExpression of membrane type 1 matrix metalloproteinase (MT1-MMP) in A2058 melanoma cells is associated with MMP-2 activation and increased tumor growth and vascularization
Sounni, Nor Eddine ULg; Baramova, Eugénia; Munaut, Carine ULg et al

in International Journal of Cancer = Journal International du Cancer (2002), 98(1), 23-28

Membrane-type metalloproteinase-1 (MT1-MMP) is a transmembrane metalloproteinase overexpressed in tumors, which plays a major role in the first step of pro-MMP-2 activation, leading to the generation of ... [more ▼]

Membrane-type metalloproteinase-1 (MT1-MMP) is a transmembrane metalloproteinase overexpressed in tumors, which plays a major role in the first step of pro-MMP-2 activation, leading to the generation of an intermediate 62 kDa species. The second step of MMP-2 activation that yields to the mature form is less understood and could involve an autocatalytic process and/or the activity of the plasminogen/plasmin system. Human melanoma A2058 cells, which express MMP-2 only in its pro-form, were used to determine the role of MT1-MMP during pericellular proteolysis and tumor progression. The induction of MT1-MMP overexpression by MT1-MMP cDNA transfection initiated the first step of MMP-2 activation. We provide evidence that a cooperation between the plasminogen/plasmin system and MT1-MMP endowed the cells with the ability to fully activate MMP-2 and with enhanced invasive properties in vitro. When injected subcutaneously in nude mice, MT1-MMP expressing clones induced rapid tumor growth and high tumor vascularization, while the control clones were poorly or not tumorigenic. Our data provide the first demonstration, in an experimental model, that MT1-MMP expression by tumor cells promotes tumor vascularization. [less ▲]

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See detailEnantiomeric separation of N-protected amino acids by non-aqueous capillary electrophoresis with dimeric forms of quinine and quinidine derivatives serving as chiral selectors
Piette, Vincent ULg; Lindner, W.; Crommen, Jacques ULg

in Journal of Chromatography. A (2002), 948(1-2), 295-302

A non-aqueous capillary electrophoretic method with quinine and tert.-butyl carbamoylated quinine as chiral selectors was developed previously for the enantioseparation of N-protected amino acids. This ... [more ▼]

A non-aqueous capillary electrophoretic method with quinine and tert.-butyl carbamoylated quinine as chiral selectors was developed previously for the enantioseparation of N-protected amino acids. This system was here applied as a screening tool for a fast evaluation of the chiral discrimination potential of six new dimeric forms of carbamoylated quinine and quinidine derivatives as chiral additives: 1,3-phenylene-bis(carbamoylated quinine), 1,6-hexamethylene-bis(carbamoylated quinine), 1,6-hexamethylene-bis(carbamoylated quinidine), trans-1,4-cyclohexylene-bis(carbamoylated quinine), trans-1,4-cyclohexylene-bis(carbamoylated-11-dodecylthio-dihydroquinine) and trans-1,4-cyclohexylene-bis(carbamoylated-11-dodecylsulfinyl-dihydroquinine). A series of 24 chiral acids, as various benzoyl, 3,5-dinitrobenzoyl (DNB) and 3,5-dinitrobenzyloxycarbonyl amino acid derivatives were investigated with regards to enantioselectivity employing these different dimeric chiral selectors. The composition of the background electrolyte was 12.5 mM ammonia, 100 mM octanoic acid, and 10 mM chiral selector in an ethanol-methanol (60:40, v/v) mixture and the enantioseparations were performed at 15 degreesC and in the reversed polarity mode at -25 kV. With these dimeric chiral selectors, higher enantioselectivity values, compared to those obtained with monomeric derivatives, were usually achieved, especially with the dimers containing dodecyl substituents. For example, an a value of 4 and a resolution value of 78 were obtained for DNB-phenylalanine, using trans-1,4-cyclohexylene-bis(carbamoylated-11-dodecylthio-dihydroquinine) as selector. (C) 2002 Elsevier Science B.V. All rights reserved. [less ▲]

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See detailEtude de l'effet de bordure dans les essais forestiers en milieu tropical
Fonton, H. N.; Claustriaux, Jean-Jacques ULg; Odjo, Th. et al

in Bulletin de la Recherche Agronomique du Bénin (2002), 35

The aim of this study is to examine the efficiency of border effect on the results analysis with the comparison of provenance and species of forest trees, it is recommended to take into account the border ... [more ▼]

The aim of this study is to examine the efficiency of border effect on the results analysis with the comparison of provenance and species of forest trees, it is recommended to take into account the border effect. Each plot has 49 trees (7 x 7); the border trees represent 49 % of the whole planted trees, and therefore 49 % of experimental unit. Twenty five essays were concerned with some repeated measurements. The experimental designs were randomized complete blocks and Latin square. The observed variables were total height and diameter at breast height. The analysis of variance showed that the differencies between plot sizes were not significant. We conclulde the use of small units under 49 trees to increase the number of repetitions and decrease the amount of the field work. [less ▲]

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See detailResistance testing in children changing human immunodeficiency virus type 1 protease inhibitor
Servais, Jean; Hainaut, M.; Schmitz, V. et al

in Pediatric Infectious Disease Journal (2002), 21(3), 214-220

Objective. To assess genotypic and phenotypic resistance testing in HIV-1-infected children failing a first protease inhibitor (PI) therapy. Methods. In a multicenter observational study 21 children, ages ... [more ▼]

Objective. To assess genotypic and phenotypic resistance testing in HIV-1-infected children failing a first protease inhibitor (PI) therapy. Methods. In a multicenter observational study 21 children, ages 3 to 16 years, were given two reverse transcriptase inhibitors and one PI (mainly ritonavir, n = 18). They were subsequently treated with single or dual PI-based therapy (predominantly nelfinavir, n = 10, or ritonavir-saquinavir, n = 7). Resistance testing was performed at the time of therapy switch via direct sequencing and a recombinant virus susceptibility assay. Results. A total of 21 genotypic and 15 phenotypic resistance profiles were obtained. Most viruses displayed several reverse transcriptase mutations; however, 7 isolates maintained a wild-type protease. Ritonavir targeted the well-known pathway containing 82, 54, 46 and other secondary (nonactive site) mutations including T74A. No in vitro cross-resistance, i.e. greater than or equal to8-fold resistance to saquinavir or amprenavir, was encountered. Secondary mutations enhanced the prediction of ritonavir resistance (i.e. L10I) and in vitro nelfinavir cross-resistance (i.e. K20R/I conferred by primary (active site) resistance mutations. Either the 82, 54, 46 mutational genotype or the phenotype showing greater than or equal to8-fold nelfinavir cross-resistance predicted a poorer virologic response to nelfinavir salvage therapy. Conclusion. In a small cohort of heavily pretreated pediatric patients, resistance testing appears to predict the response to nelfinavir as salvage for a ritonavir-based therapy. This is further supported by the correlation between ritonavir-selected mutations and in vitro nelfinavir cross-resistance. Prospective studies should assess clinical outcome in children undergoing regimen changes based on resistance testing. [less ▲]

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See detailA specific role for spermidine in the initiation phase of somatic embryogenesis in Panax ginseng CA Meyer
Monteiro, Marta; Kevers, Claire ULg; Dommes, Jacques ULg et al

in Plant Cell, Tissue & Organ Culture (2002), 68(3), 225-232

Somatic embryogenesis of Panax ginseng CA Meyer was initiated from suspension aggregates of an embryogenic callus, in a liquid medium consisting of half strength Murashige and Skoog (1962) supplemented ... [more ▼]

Somatic embryogenesis of Panax ginseng CA Meyer was initiated from suspension aggregates of an embryogenic callus, in a liquid medium consisting of half strength Murashige and Skoog (1962) supplemented with the synthetic auxin benzoselenienyl-3 acetic acid. The addition of spermidine to this initiation medium significantly increased the production of somatic embryos. In this case, the total polyamine content of the embryogenic mass was higher than that of cultures without spermidine. At day 6 of the culture, a transient accumulation of free polyamines, mainly spermidine, was observed. After this peak, free and conjugated polyamines levels did not show significant variation nor did the polyamine oxidase activity. The results clearly demonstrated that spermidine supplied to the medium was oxidised by polyamine oxidase and partially metabolised into putrescine. The role of spermidine and its interaction with auxin in the initiation of the embryogenic process in Panax ginseng are discussed in relation to embryogenic potential. [less ▲]

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See detailVers une cartographie informatisée des stations forestières
Claessens, Hugues ULg; Lejeune, Philippe ULg; Cuvelier, M. et al

in Forêt Wallonne (2002), (57), 22-30

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See detailLevels of inflammatory markers in the blood processed by autotransfusion devices during cardiac surgery associated with cardiopulmonary bypass circuit
AMAND, Théophile ULg; Pincemail, Joël ULg; Blaffart, Francine ULg et al

in Perfusion (2002), 17(2), 117-123

Intraoperative blood salvage devices allowing a reinfusion of red blood cells (RBCs) after processing of shed blood and stagnant blood in the mediastinal cavity are more and more used to reduce homologous ... [more ▼]

Intraoperative blood salvage devices allowing a reinfusion of red blood cells (RBCs) after processing of shed blood and stagnant blood in the mediastinal cavity are more and more used to reduce homologous blood requirements in cardiac surgery with cardiopulmonary bypass (CPB). As the proinflammatory activity of the shed blood also contributes to morbidity during CPB, we conducted a prospective study in order to examine the quality of autologous blood before and after processing with five different devices [BRAT2, Sequestra, Compact Advanced, Cell Saver 5 (CS5), Continuous Autologous Transfusion System (CATS)]. All systems resulted in an excellent haemoconcentration, ranging from 53.7% (Compact) to 68.9% (CATS). The concentrations and elimination rates of several inflammatory markers [IL-1beta, IL-2, IL-8, TNFalpha, myeloperoxidase (MPO), elastase] were examined. Except for the Sequestra, an important increase in concentration of IL-1beta (between 30% and 220%) has been observed after processing with each device. In contrast, the attenuation rate of IL-6 and TNFalpha (95%) was optimal for all investigated blood salvages systems. Regarding IL-8, only the CATS and CS5 systems were able to attenuate this biological parameter with an excellent efficacy. The rate of attenuation in MPO and elastase, as markers of leukocyte activation, was higher than 80% for all devices. In conclusion, the different RBC washing systems tested in this study resulted in a significant attenuation of the inflammatory response. Increased levels of IL-1beta after processing remained, however, unclear. According to the type of protocol, based on inlet haematocrit, fill and wash speeds, and wash volumes, small variations in reducing the inflammatory response have been observed from one device to another. [less ▲]

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See detailL’optimisation des structures navales: minimisation du coût de construction de la coque métallique
Rigo, Philippe ULg

in Institut pour la Promotion des Sciences de l’Ingénieur (IPSI) (2002)

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See detailBrain imaging of the central executive component of working memory
Collette, Fabienne ULg; Van der Linden, Martial ULg

in Neuroscience & Biobehavioral Reviews (2002), 26(2), 105-125

This review presents neuroimaging studies which have explored the cerebral substrates of the central executive component of the working memory model proposed by Baddeley and Hitch [working memory (1986 ... [more ▼]

This review presents neuroimaging studies which have explored the cerebral substrates of the central executive component of the working memory model proposed by Baddeley and Hitch [working memory (1986); Recent advances in learning and motivation (1974)]. These studies have demonstrated that different executive functions (manipulating and updating of information, dual-task coordination, inhibition and shifting processes) not only recruit various frontal areas, but also depend upon posterior (mainly parietal) regions. Such results are in agreement with the hypothesis that executive functions rely on a distributed cerebral network not restricted to anterior cerebral areas. Moreover, the intervention of similar prefrontal regions in a large number of executive tasks suggests that the central executive functioning must be understood in terms of different interactions between a network of regions rather than in terms of a specific association between one region and one higher-level cognitive process [less ▲]

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See detailTrading the Stability of Finite Zeros for Global Stabilization of Nonlinear Cascade Systems
Sepulchre, Rodolphe ULg; Arcak, Murat; Teel, Andrew R.

in IEEE Transactions on Automatic Control (2002), 47(3), 521-525

This note analyzes the stabilizability properties of nonlinear cascades in which a nonminimum phase linear system is interconnected through its output to a stable nonlinear system. It is shown that the ... [more ▼]

This note analyzes the stabilizability properties of nonlinear cascades in which a nonminimum phase linear system is interconnected through its output to a stable nonlinear system. It is shown that the instability of the zeros of the linear system can be traded with the stability of the nonlinear system up to a limit fixed by the growth properties of the cascade interconnection term. Below this limit, global stabilization is achieved by smooth static-state feedback. Beyond this limit, various examples illustrate that controllability of the cascade may be lost, making it impossible to achieve large regions of attractions. [less ▲]

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See detailIsolation and pharmacological activity of phenylpropanoid esters from Marrubium vulgare
Sahpaz, S.; Garbacki, Nancy ULg; Tits, Monique ULg et al

in Journal of Ethnopharmacology (2002), 79(3), 389-392

The isolation and identification of major phenylpropanoid esters from Marrubium vulgare: (+) (E)-caffeoyl-L-malic acid 1, acteoside 2, forsythoside B 3, arenarioside 4, ballotetroside 5, as well as their ... [more ▼]

The isolation and identification of major phenylpropanoid esters from Marrubium vulgare: (+) (E)-caffeoyl-L-malic acid 1, acteoside 2, forsythoside B 3, arenarioside 4, ballotetroside 5, as well as their anti-inflammatory activity are reported for the first time, We evaluated the inhibitory effects of these five compounds on cyclooxygenase (Cox) catalysed prostaglandin biosynthesis activity. Only the glycosidic phenylpropanoid esters showed an inhibitory activity towards the Cox-2 enzyme and three of them: acteoside 2, forsythoside B 3, arenarioside 4, exhibited higher inhibitory potencies on Cox-2 than on Cox-1. These results are of interest, as Cox-2 is mainly associated with inflammation and the Cox-1 inhibition with adverse side effects often observed with non-steroidal anti-inflammatory drugs. The occurence of these phenylpropanoid esters could also explain some other pharmacological properties of M. vulgare. (C) 2002 Elsevier Science Ireland Ltd. All rights reserved. [less ▲]

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See detailLanguage in Ageing Persons with Down Syndrome
Rondal, Jean-Adolphe ULg; Comblain, Annick ULg

in Down's Syndrome, Research and Practice : The Journal of the Sarah Duffen Centre (2002), 8(1), 1-9

Several cross-sectional studies and one longitudinal study were conducted on the language abilities of various cohorts of persons with Down syndrome aged between 14 and 50 years. No significant difference ... [more ▼]

Several cross-sectional studies and one longitudinal study were conducted on the language abilities of various cohorts of persons with Down syndrome aged between 14 and 50 years. No significant difference was observed on any of the receptive and productive morphosyntactic and lexical measures used, suggesting no marked change in the language of these persons from adolescence onto late adulthood. Repeated measures of cerebral metabolic rate (CMR) for fluorodeoxyglucose using a Positron Emission Tomography were made over a 4-year interval with 7 participants with Down syndrome aged between 37 and 49 years. A gradual decrease in global CMR for both cerebral hemispheres and for each participant was documented. It was particularly marked for 3 participants. However, no language deterioration could be associated with their marked lowering in CMR. [less ▲]

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See detailStudy of bacterial determinants involved in the induction of systemic resistance in bean by Pseudomonas putida BTP1
Ongena, MARC ULg; Giger, A.; Jacques, Philippe ULg et al

in European Journal of Plant Pathology (2002), 108(3), 187-196

The ability of Pseudomonas putida BTP1 to induce resistance in bean to Botrytis cinerea was demonstrated in soil experiments on plants pre-inoculated at the root level with the bacteria before challenge ... [more ▼]

The ability of Pseudomonas putida BTP1 to induce resistance in bean to Botrytis cinerea was demonstrated in soil experiments on plants pre-inoculated at the root level with the bacteria before challenge with the leaf pathogen. As a first step to characterize the molecules from BTP1 responsible for induction of systemic resistance in bean, heat-killed cells and supernatant from culture in an iron-limited medium were tested for their protective effect. Most of the resistance-eliciting activity of the strain was retained in the crude cell-free culture fluid. In vivo assays with samples from successive fractionation steps of the BTP1 supernatant led, (i) to the conclusion that salicylic acid, pyochelin and pyoverdin, previously identified as Pseudomonas determinants for induced systemic resistance (ISR), were not involved in systemic resistance triggered by BTP1, and (ii) to the isolation of fractions containing one main metabolite that retained most of the resistance-inducing activity in bean. Although this molecule remains to be structurally characterized, its isolation is an addition to the range of determinants from plant growth-promoting rhizobacteria (PGPR) known to stimulate plant defences. [less ▲]

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See detailComment je traite.... Un cancer du pancreas avance
Polus, Marc ULg; Jerusalem, Guy ULg; Sautois, Brieuc ULg et al

in Revue Médicale de Liège (2002), 57(3), 131-4

Median survival of advanced pancreatic cancer is about three months. Unfortunately, chemotherapy is not a curative approach. Chemotherapy improves the quality of life and overall survival compared to best ... [more ▼]

Median survival of advanced pancreatic cancer is about three months. Unfortunately, chemotherapy is not a curative approach. Chemotherapy improves the quality of life and overall survival compared to best supportive care. Nevertheless, as the overall survival remains disappointing, clinical research must ongoing to define better treatment regimen. [less ▲]

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See detailPrise en compte du patrimoine culturel dans les politiques européennes actuelles en matière d'environnement
Teller, Jacques ULg; Bond, A.

in Cahiers de l'Urbanisme (Les) (2002), (38),

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See detailEpidémiologie de l'hypertension artérielle
Krzesinski, Jean-Marie ULg

in Revue Médicale de Liège (2002), 57(3), 142-147

The prevalence of high blood pressure increases in our industrialized society. The main risk factors are hypertensive heredity, small birth weight for the gestational age, large increase of weight in ... [more ▼]

The prevalence of high blood pressure increases in our industrialized society. The main risk factors are hypertensive heredity, small birth weight for the gestational age, large increase of weight in teenagers, low physical activity, excess in salt and/or alcohol consumption. The normotensive people with high normal blood pressure are the future hypertensive population. [less ▲]

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See detailLa conduite de l'accompagnement de bouleau dans les jeunes plantations de hêtre (cahier technique n°19)
Kiss, S.; Fourbisseur, A.; Claessens, Hugues ULg

in Forêt Wallonne (2002), (57), 10-13

Voici la deuxième partie du cycle de deux cahiers techniques dédiés à la sylviculture en mélange du hêtre. Dans ce second volet, nous montrerons que l’envahissement est plus une aubaine qu’un fléau. Nous ... [more ▼]

Voici la deuxième partie du cycle de deux cahiers techniques dédiés à la sylviculture en mélange du hêtre. Dans ce second volet, nous montrerons que l’envahissement est plus une aubaine qu’un fléau. Nous proposerons un itinéraire sylvicole qui permet de tirer profit de l’accompagnement du bouleau pour augmenter la qualité des hêtres. Il se fonde sur une sylviculture moderne adaptée aux mélanges : la sylviculture d’arbre d’avenir. [less ▲]

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See detailOptimisation and validation of a generic method for the LC assay of six corticosteroids and salicylic acid in dermopharmaceutical forms
Marini Djang'Eing'A, Roland ULg; Pantella, A.; Bimazubute, Marcel et al

in Chromatographia (2002), 55(5-6), 263-269

A generic method was developed for the liquid chromatographic (LC) assay of six corticosteroids and salicylic acid in different dermatological formulations containing methylparaben and propylparaben or ... [more ▼]

A generic method was developed for the liquid chromatographic (LC) assay of six corticosteroids and salicylic acid in different dermatological formulations containing methylparaben and propylparaben or sorbic acid as preservatives. An adequate separation was obtained using octadecylsilica as stationary phase and a mixture of acetonitrile (MeCN) and 25 mM phosphate buffer of pH 3.5 as mobile phase. Segmented gradient elution was applied from 30 to 45% of MeCN in 9.9 minutes, then from 45 to 96% in 19.0 minutes. UV detection was performed at 240 nm. The method was validated. Very good results were obtained with respect to linearity selectivity, precision and accuracy. [less ▲]

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See detailRadiative lifetime measurements and oscillator strengths of astrophysical interest in HoIII
Zhang, Z. G.; Somesfalean, G.; Svanberg, S. et al

in Astronomy and Astrophysics (2002), 384(1), 364-370

Radiative lifetimes of three long-lived levels belonging to the 4f(10)5d configuration of Ho III have been measured, for the first time, using the time-resolved laser-induced fluorescence technique. A ... [more ▼]

Radiative lifetimes of three long-lived levels belonging to the 4f(10)5d configuration of Ho III have been measured, for the first time, using the time-resolved laser-induced fluorescence technique. A good agreement between the experimental lifetimes and theoretical results obtained within a multiconfigurational pseudo-relativistic Hartree-Fock (HFR) approach including core-polarization (CP) effects is observed provided an adequate scaling factor is applied to the <4f|r|5d> transition matrix element. From the comparison theory-experiment, it has been possible to assess the reliability of the oscillator strengths of the 4f-5d transitions of astrophysical interest, particularly for the lines depopulating the levels considered in the present work. The present results fill in a gap concerning the f-values of doubly ionized holmium and are needed for a quantitative evaluation of the holmium abundance in some peculiar stars. [less ▲]

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See detailProfessional Trajectory and Family Patrimony
Guillaume, Jean-François ULg

in Current Sociology (2002), 50(2), 203-211

Entering professional life and establishing a firm hold on a job position are often explained around notions such as integration, project and employability, which stress the role of the individual. Yet ... [more ▼]

Entering professional life and establishing a firm hold on a job position are often explained around notions such as integration, project and employability, which stress the role of the individual. Yet they actually also have a family dimension. When they try to find their way to the labour market, members of younger generation will use strategies developed in ordre to ensure the durability of a social position. They inherit professional know-how, a system of value and a network of personal relationships as well as property and financial assets. In order to consider this transmission process, the autor discusses a research that focuses on young Belgian people's trajectories of professional integration. About 30 French-speaking Belgian people were interviewed at some length, the information thus collected complementing the statistical analysis of various longitudinal data sets about the first 24 months after graduation. All had some experience of professional intergration, i.e. experience of work as salaried employees or as freelancers, but had not all secured a stable position. Researchers need to be aware of the theoretical and methodological implications arising from the juxtaposition between objective data collected in longitudinal surveys and subjective data written at the heart of biographical stories. [less ▲]

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See detailIdentification of tenuis of four French Polynesian Carapini (Carapidae : Teleostei)
Parmentier, Eric ULg; Lo-Yat, A.; Vandewalle, Pierre ULg

in Marine Biology (2002), 140(3), 633-638

Four species of adult Carapini (Carapidae) occur on Polynesian coral reefs: Encheliophis gracilis, Carapus boraborensis, C. homei and C. mourlani. Samples collected in Rangiroa and Moorea allowed us to ... [more ▼]

Four species of adult Carapini (Carapidae) occur on Polynesian coral reefs: Encheliophis gracilis, Carapus boraborensis, C. homei and C. mourlani. Samples collected in Rangiroa and Moorea allowed us to obtain different tenuis (larvae) during their settlement phases or directly inside their hosts. These were separated into four lots on the basis of a combination of pigmentation, meristic, morphological, dental and otolith (sagittae) features. Comparison of these characters with those of the adults allows, for the first time, taxonomic identification of these tenuis-stage larvae. [less ▲]

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See detailA Grassmann-Rayleigh quotient iteration for computing invariant subspaces
Absil, P.-A.; Mahony, R.; Sepulchre, Rodolphe ULg et al

in SIAM Review (2002), 44(1), 57-73

The classical Rayleigh quotient iteration (RQI) allows one to compute a one-dimensional invariant subspace of a symmetric matrix A. Here we propose a generalization of the RQl which computes a p ... [more ▼]

The classical Rayleigh quotient iteration (RQI) allows one to compute a one-dimensional invariant subspace of a symmetric matrix A. Here we propose a generalization of the RQl which computes a p-dimensional invariant subspace of A. Cubic convergence is preserved and the cost per iteration is low compared to other methods proposed in the literature. [less ▲]

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See detailHeartburn in Belgium: prevalence, impact on daily life, and utilization of medical resources
Louis, Edouard ULg; DeLooze, D.; Deprez, P. et al

in European Journal of Gastroenterology & Hepatology (2002), 14(3), 279-284

Background Gastro-oesophageal reflux disease (GORD) is a frequently occurring disease that may be considered a public health issue, particularly in developed countries. The specificity of heartburn for ... [more ▼]

Background Gastro-oesophageal reflux disease (GORD) is a frequently occurring disease that may be considered a public health issue, particularly in developed countries. The specificity of heartburn for the diagnosis of GORD is good. Our aim was to define the prevalence of heartburn in Belgium, characterizing both its impact on everyday life and the ensuing use of medical resources. Methods Two thousand people living in Belgium, selected randomly after stratification, were interviewed face to face. The main question in the questionnaire used in this interview concerned the presence over the previous 12 months of a burning sensation in the epigastric and/or retrosternal region. This was followed by 21 secondary questions on the characteristics of the population studied, the impact of heartburn on everyday life, and the medical resources used. Results Twenty-eight per cent of the population interviewed reported heartburn. This symptom was present at least once a week in 42% of sufferers. Heartburn was more frequent in women than men (P < 0.05) and was not distributed uniformly throughout the various regions of the country (P < 0.05). Seventy-seven per cent of the people with heartburn found that it had a significantly negative impact on their daily lives (in 27%, this effect was strong). Heartburn associated with a substantial negative impact on daily life was characterized by a higher frequency of symptoms (P < 0.0001), a longer duration of the problem (P= 0.006), and the presence of pain (P < 0.0001) and anxiety (P < 0.0001). Fifty-six per cent of individuals with heartburn had already sought medical advice, 45% had undergone an upper-gastrointestinal tract endoscopy, and 59% were taking medications. Among patients complaining that heartburn had a substantial negative effect on their everyday lives, 21.6% had not sought medical advice and 22.2% did not take any medication. Conclusion Heartburn is very frequent in Belgium and is associated with a considerable negative impact on everyday life. It also generates a significant use of medical resources. However, among the patients complaining of a substantial negative effect on their daily lives, one-fifth (which would represent 1.5% of the Belgian population) seemed to lack appropriate care. [less ▲]

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See detailModelling the Danube-influenced North-western continental shelf of the Black Sea. I: Hydrodynamical processes simulated by 3-D and box models
Beckers, Jean-Marie ULg; Grégoire, Marilaure ULg; Nihoul, Jacques ULg et al

in Estuarine Coastal & Shelf Science (2002), 54(3), 453-472

A hydrodynamical modelling of the Black Sea is presented using the GHER 3-D primitive equation model. Results of a very high resolution model with 5 km grid size are analysed and the dominant features of ... [more ▼]

A hydrodynamical modelling of the Black Sea is presented using the GHER 3-D primitive equation model. Results of a very high resolution model with 5 km grid size are analysed and the dominant features of general circulation in the Black Sea are highlighted. Compared with a coarse resolution model, forced with the same climatic monthly averaged atmospheric data, the high resolution model exhibits stronger variability, including frontal structures and coastal upwellings induced by baroclinic instabilities, in particular along the Turkish coast. A comparison of the shelf-open sea exchanges, with particular focus on the cold intermediate waters, shows that both models lead to a replenishment of the CIL in the basin interior by cold waters formed on the shelf. Due to the better representation of frontal structures, the high resolution model is an appropriate candidate for coupling with a biological model. Problems of calibration, interpretation and data availability typically arise from this kind of coupled 3-D model. In order to overcome such difficulties, the results of the 3-D hydrodynamical model are used to guide the development of an integrated 0-D box model capable of achieving the objectives of projects like EROS21, where the effect of changes in the Danube inflows on the shelf ecosystem is investigated. The 0-D model is thus designed to cover this region and is obtained through integration over an appropriate variable volume. The integration procedure shows where the weaknesses of an 0-D approach might lie. Diagnoses in the 3-D model of the integral quantities show the range of uncertainty one can expect in the exchange laws of the 0-D model. (C) 2002 Elsevier Science Ltd. All rights reserved. [less ▲]

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See detailIncreased TGFβ1 plasma level in patients with lung cancer: potential mechanisms
Barthelemy, Nicole ULg; David, Jean-Louis ULg; Bosquee, Léon ULg et al

in European Journal of Clinical Investigation (2002), 32(3), 193-198

Background Plasma transforming growth factor β1 (TGFβ1) levels are elevated in patients with lung cancer. As TGFβ1 is mainly found in platelets and as nonmalignant pulmonary diseases (NMPD) are frequently ... [more ▼]

Background Plasma transforming growth factor β1 (TGFβ1) levels are elevated in patients with lung cancer. As TGFβ1 is mainly found in platelets and as nonmalignant pulmonary diseases (NMPD) are frequently associated with lung cancer, we investigated the potential contribution of platelet degranulation and/or of a concomitant NMPD to the increased plasma levels of TGFβ1 reported in patients with lung cancer. Materials and Methods Blood samples were collected in duplicate from 30 healthy subjects, 14 patients suffering from NMPD and 37 patients with lung cancer. The platelet count was determined and the samples were processed to obtain plasma. One sample was collected in EDTA (EDTA plasma) and the other in a mixture inhibiting platelet degranulation (PIM plasma). TGFβ1 concentrations and β-thromboglobulin (βTG) levels, an index of platelet degranulation, were measured in both plasma samples. Results TGFβ1 and βTG plasma levels measured in PIM plasma were lower than those obtained in EDTA plasma. With respect to PIM plasma, both TGFβ1 and βTG levels were higher in patients with lung cancer than those with NMPD and in healthy individuals. In patients with NMPD, only TGFβ1 levels were increased as compared to healthy controls, βTG levels being similar. Conclusion Methods for collecting and processing blood samples are critical in determining reliable circulating TGFβ1 levels. Increased TGFβ1 plasma levels observed in patients with lung cancer are related, at least partly, to concomitant NMPD and also to platelet degranulation as proved by increased βTG levels. [less ▲]

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See detailLe travail de fin d'études, entre scientificité et magie
Scheepers, Caroline ULg

in Enjeux : Revue de Formation Continuée et de Didactique du Français (2002), 53(mars), 23-31

L'article porte sur le travail de fin d’études qui, en Belgique francophone, conclut l’enseignement supérieur de type court . Notre recherche, menée dans le cadre d’un mémoire de DES en didactique ... [more ▼]

L'article porte sur le travail de fin d’études qui, en Belgique francophone, conclut l’enseignement supérieur de type court . Notre recherche, menée dans le cadre d’un mémoire de DES en didactique, poursuivait une double visée. Dans un premier temps, il nous a paru opportun d’interroger des formateurs des Hautes Ecoles et d’anciens étudiants à propos du travail de fin d’études, s’agissant des modalités d’évaluation, de la préparation des étudiants ou des principaux facteurs d’échec ou de réussite. Les réponses que nous avons obtenues mettent en lumière de nombreux dysfonctionnements quant à l’encadrement et à l’évaluation des productions des étudiants. Ce constat, assez sombre, nous a incitée à proposer, dans un second temps, des pistes didactiques, susceptibles de pallier, modestement et partiellement, les carences recensées. Pour ce faire, nous avons notamment tenté de mettre à jour les spécificités discursives du travail de fin d’études, spécificités que nous nous proposons de faire découvrir par les étudiants. Nous centrerons d’ailleurs plus particulièrement notre propos sur cet aspect. Insistons enfin sur le caractère purement exploratoire de notre recherche : les conclusions que nous allons énoncer ici sont toutes provisoires et parcellaires. [less ▲]

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See detailAdditive effects of raloxifene and alendronate on bone density and biochemical markers of bone remodeling in postmenopausal women with osteoporosis
Johnell, O.; Scheele, W. H.; Lu, Y. L. et al

in Journal of Clinical Endocrinology and Metabolism (2002), 87(3), 985-992

Both raloxifene (RLX) and alendronate (ALN) can treat and prevent new vertebral fractures, increase bone mineral density (BMD), and decrease biochemical markers of bone turnover in postmenopausal women ... [more ▼]

Both raloxifene (RLX) and alendronate (ALN) can treat and prevent new vertebral fractures, increase bone mineral density (BMD), and decrease biochemical markers of bone turnover in postmenopausal women with osteoporosis. This phase 3, randomized, double-blind 1-yr study assessed the effects of combined RLX and ALN in 331 postmenopausal women with osteoporosis (femoral neck BMD T-score, less than -2). Women (aged less than or equal to75 yr; greater than or equal to2 yr since their last menstrual period) received placebo, RLX 60 mg/d, ALN 10 mg/d, or RLX 60 mg/d and ALN 10 mg/d combined. At baseline, 6 and 12 months, BMD was measured by dual x-ray absorptiometry. The bone turnover markers serum osteocalcin, bone-specific alkaline phosphatase, and urinary N- and C-telopeptide corrected for creatinine were measured. The effects of RLX and ALN were considered to be independent and additive if the interaction effect was not statistically significant (P > 0.10) in a two-way ANOVA model. All changes in BMD and bone markers at 12 months were different between placebo and each of the active treatment groups, and between the RLX and RLX+ALN groups (P < 0.05). On average, lumbar spine BMD increased by 2.1,4.3, and 5.3% from baseline with RLX, ALN, and RLX+ALN, respectively. The increase in femoral neck BMD in the RLX+ALN group (3.7%) was greater than the 2.7 and 1.7% increases in the ALN (P = 0.02) and RLX (P < 0.001) groups, respectively. The changes from baseline to 12 months in bone markers ranged from 7.1 to -16.0% with placebo, -23.8 to -46.5% with RLX, -42.3 to -74.2% with ALN, and -54.1 to -81.0% in the RLX+ALN group. RLX and ALN increased lumbar spine and femoral neck BMD, and decreased osteocalcin and C-telopeptide corrected for creatinine in an additive and independent manner, because the interaction effects were not significant. Although the ALN group had changes in BMD and bone markers that were approximately twice the magnitude as in the RLX group, it is not known how well these changes correlate to the clinical outcome of fracture. RLX+ALN reduced bone turnover more than either drug alone, resulting in greater BMD increment, but whether this difference reflects better fracture risk reduction was not assessed in this study. [less ▲]

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See detailCoastal-open ocean exchange in the Black Sea: Observations and modelling
Stanev, Emil; Beckers, Jean-Marie ULg; Lancelot, Christiane et al

in Estuarine Coastal & Shelf Science (2002), 54(3), 601-620

The interaction between physical and biological processes in the areas of continental margins governs the variability of ecosystems. The complexity of processes in these areas requires detailed studies ... [more ▼]

The interaction between physical and biological processes in the areas of continental margins governs the variability of ecosystems. The complexity of processes in these areas requires detailed studies combining modelling and surveying efforts. One promising step in this direction was undertaken in the framework of the EROS 21 project, focusing on the shelf part of the north-western Black Sea. In the present paper, we focus on the results of physical studies aiming to improve the understanding of the fundamental exchange processes in the ocean margins, as well as to quantify some of them in the Black Sea. We illustrate the capabilities of circulation models to reproduce physical processes with different time- and space-scales: coastal waves, internal waves, baroclinic Rossby and topographic waves. Another class of important phenomena in the coastal zone is associated with convection. Sources at the sea surface and in the outflow areas give rise to plume dynamics that play a crucial role in the vertical mixing and provide the mechanism for water-mass formation. Most of the results are illustrated for the shelf part of the Black Sea. The verification of simulations is performed by comparison with survey data, altimeter data from the Topex/Poseidon mission and radiotracer observations. The latter, in combination with simulations from circulation models, are used to trace the penetration of tracers into the intermediate and deep layers. We show that although most Sr-90 is introduced by river runoff, large amounts of this signal penetrate the halocline in the Bosphorus Straits area and along the southern coast. Another important fraction of the river water penetrates the intermediate layers at the shelf edge in the north-western Black Sea. (C) 2002 Elsevier Science Ltd. All rights reserved. [less ▲]

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See detailOn-line soil mechanical resistance mapping and correlation with soil physical properties for precision agriculture
Sirjacobs, Damien ULg; Hanquet, Bernard; Lebeau, Frédéric ULg et al

in Soil & Tillage Research (2002), 64

Measurement of local soil strength may be used for real time regulation of tillage parameters in precision agriculture. Cartography of soil physical properties will also facilitate the study of their ... [more ▼]

Measurement of local soil strength may be used for real time regulation of tillage parameters in precision agriculture. Cartography of soil physical properties will also facilitate the study of their influence on plant development and yields. The aim of this research was to develop and test in field conditions a sensor measuring on-line soil strength variations. The sensor was constituted of a thin blade pulled in the soil at constant depth and speed and a beam which transferred the soil–blade forces to a transducer fixed on the machine. This transducer measured the draft force (Fx), the vertical force (Fz) and the moment (My). A field experiment was performed in 2 ha field of silt soil (Hesbaye, Belgium). A soil strength map of the field was established by pulling the sensor at 5 m interline separation by a tractor equipped with a DGPS receiver. The relationship between the recorded forces and several soil physical parameters was studied by identifying 10 control plots on the sensor track. In each of them, cone index penetrometry profiles and soil water content were measured. Soil samples were taken in the centre of the plots to determine cohesion and internal friction angle, simple compression resistance, Atterberg limits, granulometry and pF curves. Triaxial tests identified over-consolidated soils in plots situated in the pounds of the field. Based on the parameters measured in the other plots, significant relationships were established between (1) a global penetrometry index and the Fx and My solicitations measured by the sensor; (2) gravimetric water content and the vertical force Fz. Interpolation by inverse distance with a range of 45 m gave the best result for the cartography of the three measured signals (Fx, Fz and My). The confrontation of those maps with pedological and topographic maps together with the statistical relationships and the farmer’s knowledge of the field showed high consistency. The results of this experiment in field conditions are encouraging and show the promising perspective of technological innovations allowing on-line characterisation of soil physical state for precision agriculture. [less ▲]

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See detailThe Quaternary fault in Jiamu area, the Xinjiang Uygur Autonomous Region
Huafu, Lu; Shengli, Wang; Suppe, John et al

in Chinese Sciences Bulletin (2002), 47(6), 494-499

The Quaternary Tailan River fault has been found in the Tianshan foothills area, the Xinjiang Uygur Autonomous Region. It is the recent boundary fault of the Tarim Basin coupling with the West Tianshan ... [more ▼]

The Quaternary Tailan River fault has been found in the Tianshan foothills area, the Xinjiang Uygur Autonomous Region. It is the recent boundary fault of the Tarim Basin coupling with the West Tianshan Mountains. In the light of measurement data of the slip which cuts the Quaternary deposits of different ages, the Quaternary kine- matic figures of the Tailan River fault are estimated as fol- lows: crustal shortening 3.7 km and shortening rate 1.59 mm/a, uplift of Tianshan Mountains 1.34 km and uplift rate 0.56 mm/a, and additional relief of 900 m. Considering the contribution of the Gumubiezi anticline close to the south of the Tailan River fault, the Quaternary crustal shortening and shortening rate of the Jiamu area are 4.8 km and 2 mm/a respectively. The above-mentioned data coincide with the crustal shortening rate calculated from the growth strata in the Kuqa area, as well as the GPS measurements in the Lake Issyk area and the Korla-Urumqi area, reflecting the fast thrusting period within the shortening tectonic processes of the rejuvenation foreland basin in front of the southern foothill of the West Tianshan Mountains since Neogene. [less ▲]

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See detailProliferative generation of mammalian auditory hair cells in culture
Malgrange, Brigitte ULg; Belachew, Shibeshih ULg; Thiry, Marc ULg et al

in Mechanisms of Development (2002), 112(1-2), 79-88

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See detailModelling the Danube-influenced north-western continental shelf of the Black Sea. II: Ecosystem response to changes in nutrient delivery by the Danube River after its damming in 1972
Lancelot, Christiane; Staneva, J.; Van Eeckhout, D. et al

in Estuarine Coastal & Shelf Science (2002), 54(3), 473-499

The ecological model BIOGEN, describing the carbon, nitrogen, phosphorus and silicon cycling throughout aggregated chemical and biological compartments of the planktonic and benthic marine systems, has ... [more ▼]

The ecological model BIOGEN, describing the carbon, nitrogen, phosphorus and silicon cycling throughout aggregated chemical and biological compartments of the planktonic and benthic marine systems, has been implemented in the north-western Black Sea to assess the response of this coastal ecosystem to eutrophication by the Danube River. The trophic resolution of BIOGEN was chosen to simulate the major ecological changes reported in this coastal area since the 1960s. Particular attention was paid to establishing the link between quantitative and qualitative changes in nutrients, phytoplankton composition and food-web structures. The BIOGEN numerical code structure includes 34 state variables assembled in five interactive modules describing the dynamics of (1) phytoplankton composed of three distinct groups, each with a different trophic fate (diatoms, nanophytoflagellates, non-silicified opportunistic species); (2) meso- and microzooplankton; (3) trophic dead-end gelatinous organisms composed of three distinct groups (the omnivorous Noctiluca and the carnivores Aurelia and the alien Mnemiopsis), and organic matter degradation and associated nutrient regeneration processes by (4) planktonic and (5) benthic bacteria. The capability of the BIOGEN model to simulate the recent ecosystem changes reported for the Black Sea was demonstrated by running the model for the period 1985-1995. The BIOGEN code was implemented in an aggregated and simplified representation of the north-western Black Sea hydrodynamics. The numerical frame consisted of coupling a 0-D BIOGEN box model subjected to the Danube with a 1-D BIOGEN representing the open-sea boundary conditions. Model results clearly showed that the eutrophication-related problems of the north-western Black Sea were not only driven by the quantity of nutrients discharged by the Danube, but that the balance between them was also important. BIOGEN simulations clearly demonstrated that phosphate, rather than silicate, was the limiting nutrient driving the structure of the phytoplankton community and the planktonic food-web. In particular, it showed that a well-balanced N:P:Si nutrient enrichment, such as that observed in 1991, had a positive effect on the linear, diatom-copepod food-chain, while the regenerated-based microbial food-chain remained at its background level. When present, the gelatinous carnivores also benefited from this enrichment throughout their feeding on copepods. A synergetic effect of fishing pressure and cultural eutrophication was further indirectly suggested by modifying the mortality coefficient of copepods. However, BIOGEN scenarios with unbalanced nutrient inputs, such as nitrogen or phosphate deficiency recorded in 1985 and 1995, predicted the dominance of an active microbial food-web in which bacteria and microzooplankton played a key role; the former as nutrient regenerator, the latter as a trophic path to the copepods and hence to the carnivorous. In such conditions, however, a significant biomass reduction of all gelatinous organisms was simulated, in perfect agreement with recent observations. From these model scenarios it is suggested that the observed positive signs of Black Sea ecosystem recovery might well be related to the reduction of nutrient loads in particular phosphate, by the Danube. (C) 2002 Elsevier Science Ltd. All rights reserved. [less ▲]

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See detailUltraviolet emissions from the magnetic footprints of Io, Ganymede and Europa on Jupiter
Clarke, J. T.; Ajello, Joseph M.; Ballester, G. et al

in Nature (2002), 415(6875), 997-1000

Io leaves a magnetic footprint on Jupiter's upper atmosphere that appears as a spot of ultraviolet emission that remains fixed underneath Io as Jupiter rotates(1-3). The specific physical mechanisms ... [more ▼]

Io leaves a magnetic footprint on Jupiter's upper atmosphere that appears as a spot of ultraviolet emission that remains fixed underneath Io as Jupiter rotates(1-3). The specific physical mechanisms responsible for generating those emissions are not well understood, but in general the spot seems to arise because of an electromagnetic interaction between Jupiter's magnetic field and the plasma surrounding Io, driving currents of around 1 million amperes down through Jupiter's ionosphere(4-6). The other galilean satellites may also leave footprints, and the presence or absence of such footprints should illuminate the underlying physical mechanism by revealing the strengths of the currents linking the satellites to Jupiter. Here we report persistent, faint, far-ultraviolet emission from the jovian footprints of Ganymede and Europa. We also show that Io's magnetic footprint extends well beyond the immediate vicinity of Io's flux-tube interaction with Jupiter, and much farther than predicted theoretically(4-6); the emission persists for several hours downstream. We infer from these data that Ganymede and Europa have persistent interactions with Jupiter's magnetic field despite their thin atmospheres. [less ▲]

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See detailPotential of using Daphnia magna (crustacea) developing in an aerated waste stabilisation pond as a commercial source of chitin
Cauchie, Henry-Michel ULg; Versali, Marie-France ULg; Hoffmann, L. et al

in Aquaculture (2002), 205(1-2), 103-117

The potential of using the planktonic crustacean Daphnia magna as a commercial source of chitin was studied on the basis of the estimation of the amount of chitin produced annually by this species and the ... [more ▼]

The potential of using the planktonic crustacean Daphnia magna as a commercial source of chitin was studied on the basis of the estimation of the amount of chitin produced annually by this species and the specifications of this kind of chitin. D. magna was found to have a significant chitin content, ranging from 3% to 7% of the body dry weight. During three consecutive years, chitin biomass (B) and daily somatic chitin production (daily P-SOM) were monitored in a 59,000-m(2) aerated waste stabilisation pond located in the Grand-Duchy of Luxembourg (Western Europe). These variables were found to vary a lot seasonally. Maximum values were observed in summer (B > 40 kg chitin; daily P-SOM > 20 kg chitin day(-1)). Annual somatic chitin production reached on average 1200 kg chitin year(-1). The amount of chitin generated by the moulting of the daphnids (i.e. chitin contained in the exuviae) can also constitute a significant source of chitin, reaching about 1220 kg chitin year(-1). Chitin was isolated from D. magna, following three different processing routes. The specifications of the isolated and purified chitin were similar to those of commercial chitin extracted from crabs and shrimps. The average molecular weight varied from 600,000 to 2,600,000 depending on the processing route, The isolated chitin had a low N content indicating a high degree of acetylation. (C) 2002 Elsevier Science B.V. All rights reserved. [less ▲]

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See detailControl of the radical polymerization of tert-butyl methacrylate in water by a novel combination of sodium nitrite and iron(II) sulfate
Detrembleur, Christophe ULg; Teyssié, Philippe; Jérôme, Robert ULg

in Macromolecules (2002), 35(5), 1611-1621

Addition of iron(II) sulfate to sodium nitrite is a new way to control the radical polymerization of tert-butyl methacrylate (tBMA) in water at 80 degreesC. Nitric oxide is released in the reaction medium ... [more ▼]

Addition of iron(II) sulfate to sodium nitrite is a new way to control the radical polymerization of tert-butyl methacrylate (tBMA) in water at 80 degreesC. Nitric oxide is released in the reaction medium as result of the reduction of sodium nitrite by FeSO4. This reaction is of utmost importance because three repeated additions of an alkyl radical to nitric oxide leads to the formation of nitroxide radicals. The basic mechanism for the control of the radical polymerization is thus a nitroxide-mediated process. [less ▲]

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See detailNucleon nucleon interaction in a chiral constituent quark model
Bartz, Daniel ULg; Stancu, Floarea ULg

in Nuclear Physics A (2002), A699(1-2), 316-319

We study the nucleon-nucleon interaction within a chiral constituent quark model where the hyperfine interaction is due to pseudoscalar meson exchange. We calculate the S-3(1) and S-1(0) phase shifts by ... [more ▼]

We study the nucleon-nucleon interaction within a chiral constituent quark model where the hyperfine interaction is due to pseudoscalar meson exchange. We calculate the S-3(1) and S-1(0) phase shifts by using the resonating group method. Their behaviour clearly indicates the presence of a strong repulsive core at short distance. This is due to the spin-flavour symmetry of the interaction and to the quark interchange between the two interacting nucleons. We add a sigma-meson exchange quark-quark interaction which provides a medium range attraction necessary to describe the S-1(0) phase shift. We also explore the role of a tensor interaction at the quark level. [less ▲]

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See detailLithiation of toluene by organolithium compounds activated by lithium polyether alkoxides
Nugay, Nihan; Nugay, Turgut; Jérôme, Robert ULg et al

in Journal of Molecular Catalysis A: Chemical (2002), 179(1-2), 59-64

The catalytic effect of polyether alkoxides (PEAs) on the activity of organolithium. compounds as metallating agent has been investigated. Toluene has been lithiated by using different organolithiums ... [more ▼]

The catalytic effect of polyether alkoxides (PEAs) on the activity of organolithium. compounds as metallating agent has been investigated. Toluene has been lithiated by using different organolithiums activated by various PEAs. It has been found that n-BuLi, yields higher conversion with 100% benzylic position metallation, whereas sec-BuLi gives some metallation at ring positions with the most reactive ligand, lithium 2-methoxy ethoxide (LiOEM). Optimum PEA to organolithium molar ratio for both sec- and n-BuLi activated by LiOEM where the amount of toluene being kept constant, was found to be as 3:1 with highest yield and regioselectivity. Substantial increment in yield was observed when the amount of substrate increased whereas regioselectivity stayed almost constant. It was also found that, for a constant reactant molar ratio (3:1:15) for which the optimum results were achieved, reaction began early and then yield values increased with time whereas upon increase in reaction temperature from -78 to 20degreesC, the benzylic metallation yield increased drastically while keeping the same regioselectivity high. [less ▲]

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See detailSodium nitrite and ascorbic acid: a metal-free combination that controls the free-radical polymerization of tert-butyl methacrylate in water
Detrembleur, Christophe ULg; Mouithys-Mickalad, Ange ULg; Teyssié, Philippe et al

in e-Polymers (2002), (4), 1-16

A mixture of sodium nitrite and ascorbic acid is able to control the radical polymerization of tert-butyl methacrylate (tBMA) in water at 80°C. Indeed, sodium nitrite is reduced by the ascorbic acid, and ... [more ▼]

A mixture of sodium nitrite and ascorbic acid is able to control the radical polymerization of tert-butyl methacrylate (tBMA) in water at 80°C. Indeed, sodium nitrite is reduced by the ascorbic acid, and the nitric oxide (NO) which is formed in situ is nothing but a promoter of nitroxyl radicals. The radical polymerization of tBMA is thus basically controlled by a nitroxide-mediated process. [less ▲]

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See detailATMOS version 3 water vapor measurements: Comparisons with observations from two ER-2 Lyman-alpha hygrometers, MkIV, HALOE, SAGE II, MAS, and MLS
Michelsen, Hope A.; Manney, Gloria L.; Irion, Fredrick W. et al

in Journal of Geophysical Research. Atmospheres (2002), 107(D3),

[1] We have compared a new version of Atmospheric Trace Molecule Spectroscopy Experiment (ATMOS) retrievals (version 3) of stratospheric and mesospheric water vapor with observations from shuttleborne ... [more ▼]

[1] We have compared a new version of Atmospheric Trace Molecule Spectroscopy Experiment (ATMOS) retrievals (version 3) of stratospheric and mesospheric water vapor with observations from shuttleborne, satelliteborne, balloonborne, and aircraftborne instruments. These retrievals show agreement to within 5% with the MkIV observations in the middle and lower stratosphere. ATMOS agrees with the National Oceanic and Atmospheric Administration (NOAA) Lyman-alpha hygrometer to within 5% except for features with spatial scales less than the vertical resolution of ATMOS (such as the lower stratospheric seasonal cycle). ATMOS observations are 10-16% lower than measurements from the Harvard Lyman-alpha hygrometer in the lower stratosphere and are 7-14% higher than those from the Microwave Limb Sounder (MLS; prototype version 0104) throughout most of the stratosphere. Agreement is within 7% with the Millimeter-Wave Atmospheric Sounder (MAS; version 20) in the middle and upper stratosphere, but differences are closer to 13% in the lower stratosphere. Throughout the stratosphere, agreement is within 8% with the Halogen Occultation Experiment (HALOE; version 19). ATMOS data from 1994 show agreement with the Stratospheric Aerosol and Gas Experiment II (SAGE II; version 6) values to within 8% in the middle stratosphere, but ATMOS observations are systematically higher than those from SAGE II by as much as 41% in the lower stratosphere. In contrast, ATMOS 1985 values are systematically similar to50% lower than SAGE II values from sunset occultations in the lower stratosphere near 70 hPa but appear to be in better agreement with sunrise occultations. Version 3 retrievals in the upper stratosphere and lower mesosphere are typically 5-10% lower than version 2 values between 1 and 0.05 hPa. This reduction improves agreement with HALOE, MAS, and MLS upper atmospheric observations, but ATMOS values still tend to be higher than values from these instruments in the middle mesosphere. Agreement among the instruments compared here (except for SAGE II) is generally within 15% in the middle to lower stratosphere and mesosphere and within 10% in the middle to upper stratosphere. At altitudes near 30 km, all instruments (including SAGE II) agree to within 10%. [less ▲]

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See detailImportance of Tumor Regression Assessment in Predicting the Outcome in Patients with Locally Advanced Rectal Carcinoma Who Are Treated with Preoperative Radiotherapy
Bouzourene, Hanifa; Bosman, Fred; Seelentag, Walter et al

in Cancer (2002), 94(4), 1121-1130

BACKGROUND: Locally advanced rectal carcinoma has a poor prognosis. However, <br />since the introduction of preoperative radiotherapy, the outcome of patients with <br />rectal carcinoma has been ... [more ▼]

BACKGROUND: Locally advanced rectal carcinoma has a poor prognosis. However, <br />since the introduction of preoperative radiotherapy, the outcome of patients with <br />rectal carcinoma has been reported to have improved. Nevertheless, to the authors’ <br />knowledge few data are available regarding the histopathologic response to <br />radiotherapy as assessed on surgical specimens as a potential predictive factor for <br />outcome. <br />METHODS: To estimate the effect of radiotherapy on rectal carcinoma, the authors <br />retrospectively reviewed the surgical specimens of 102 patients with T3-4, N0 or <br /> N1 rectal carcinoma and 1 patient with T2 but N1 rectal carcinoma. All patients <br />were treated preoperatively with a hyperfractionated accelerated radiotherapy <br />schedule in a prospective protocol (Trial 93-01). Using a standardized approach, <br />tumor regression was graded using a system that varies from Grade 1 (tumor <br />regression Grade [TRG] 1) when complete tumor regression is observed to Grade 5 <br />(TRG5) when no tumor regression is observed. <br />RESULTS: Radiotherapy resulted in tumor downstaging in 43% of the patients. <br />There were 2 pT1 tumors (2%), 21 pT2 tumors (20%), 66 pT3 tumors (64%), and 14 <br />pT4 tumors (14%) after treatment. Regional lymph nodes were involved in 55 <br />patients (53%). None of the patients demonstrated a complete tumor regression <br />after radiotherapy, but in 79% of the specimens a partial tumor regression was <br />observed (TRG1: 0%; TRG2: 20%; TRG3: 39%; TRG4: 20%; and TRG5: 21%). The <br />median actuarial overall survival (OS) and disease-free survival (DFS) were 52 <br />months. Actuarial local recurrence rates at 2 years and 5 years were 6.4% and 7.6%, <br />respectively. Univariate analysis showed the actuarial DFS to be significantly lower <br />in patients with lymph node metastases (P 0.0004) and advanced pT stages <br />(pT3-4) (P 0.03). A favorable outcome for OS, DFS, and local control was <br />observed in patients with TRG2-4 (i.e., responders) compared with patients with <br />TRG5 (i.e., nonresponders), but also in patients with low residual tumor cell <br />density (TRG2, 3, and 4). On multivariate analysis, TRG remained an independent <br />prognostic indicator for local tumor control. <br />CONCLUSIONS. Tumor regression as well as residual tumor cell density were found <br />to be predictive factors of survival in rectal carcinoma patients after preoperative <br />radiotherapy. Even after preoperative radiotherapy, the pathologic stage of the <br />surgical specimen remained a prognostic factor. The use of a standardized approach <br />for pathologic evaluation must be implemented to allow comparison between <br />the results of various treatment approaches. [less ▲]

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See detailOn a three-body confinement force in hadron spectroscopy
Pepin, S.; Stancu, Floarea ULg

in Physical Review. D : Particles and Fields (2002), D65

Recently it has been argued that a three-body colour confinement interaction can affect the stability condition of a three-quark system and the spectrum of a tetraquark described by any constituent quark ... [more ▼]

Recently it has been argued that a three-body colour confinement interaction can affect the stability condition of a three-quark system and the spectrum of a tetraquark described by any constituent quark model. Here we discuss the role of a three-body colour confinement interaction in a simple quark model and present some of its implications for the spectra of baryons, tetraquarks and six-quark systems. [less ▲]

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See detailAnalogy in adsorption behavior of homopolyelectrolyte mixtures as compared to analogous diblock polyampholytes
Mahltig, Boris; Gohy, Jean-François; Jérôme, Robert ULg et al

in Journal of Polymer Science. Part B, Polymer Physics (2002), 40(4), 338-345

The adsorption behavior of aqueous mixtures of the homopolyelectrolytes poly(methacrylic acid) (PMAA) and poly[(dimethylamino)ethyl methacrylate] (PDMAEMA) was investigated in comparison with the ... [more ▼]

The adsorption behavior of aqueous mixtures of the homopolyelectrolytes poly(methacrylic acid) (PMAA) and poly[(dimethylamino)ethyl methacrylate] (PDMAEMA) was investigated in comparison with the adsorption of the ampholytic diblock copolymer PMAA-b-PDMAEMA on silicon substrates. Ellipsometry was used to determine the amount of adsorbed homopolyelectrolyte and diblock polyampholyte. Furthermore, the topography of the adsorbed polymers was investigated with atomic force microscopy (AFM) and compared with the structures observed in aqueous solutions by dynamic light scattering (DLS). For all types of investigated polyelectrolytic mixtures or the single polyampholyte, the adsorption was strongly influenced by the pH of the polymer solution. Although single homopolyelectrolytes showed only one maximum in adsorption according to their charge, the mixtures made from these homopolyelectrolytes showed two or three maxima. The third maximum near the isoelectric point of the mixture was assigned to a new species formed by aggregation of the two homopolyelectrolytes. Altogether, the adsorption behavior of the polyelectrolytic mixtures was in between the behavior of the pure homopolyelectrolytes and the analogous polyampholytes and therefore understandable from both of these polymer species.(C) 2002 John Wiley Sons, Inc. [less ▲]

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See detailM1/E2 transition rates in Fe x through Fe XIII measured at a heavy-ion storage ring
Trabert, E.; Gwinner, G.; Wolf, A. et al

in Journal of Physics B-Atomic Molecular and Optical Physics (2002), 35(3), 671-689

The rates of several electric-dipole forbidden decays of 3p and 3d levels in Cl-, S-, P- and Si-like ions of Fe have been measured optically at a heavy-ion storage ring. In several cases, more than one ... [more ▼]

The rates of several electric-dipole forbidden decays of 3p and 3d levels in Cl-, S-, P- and Si-like ions of Fe have been measured optically at a heavy-ion storage ring. In several cases, more than one decay contributes to a given decay curve, which complicates the analysis. The lifetime results, with a precision range from 0.6 to 20%, compare well with some theoretical predictions, but are more precise. They are also more precise than some experimental data from an electrostatic ion trap. [less ▲]

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