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See detailEtude des séries chronologiques par les méthodes de décomposition
Palm, Rodolphe ULg; Brostaux, Yves ULg

in Notes de Statistique et d'Informatique (2009), (1), 1-17

This note briefly describes the main methods of analysing time series by a decomposition into a trend, a seasonal variation, and residuals. The methods are illustrated by an example analysed with Minitab ... [more ▼]

This note briefly describes the main methods of analysing time series by a decomposition into a trend, a seasonal variation, and residuals. The methods are illustrated by an example analysed with Minitab software. [less ▲]

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See detailAnalysis of 13 Million Individual Patient Records Pertaining To Pap Smears, Colposcopies, Biopsies and Surgery on The Uterine Cervix (Belgium, 1996–2000)
Arbyn, Marc; Simoens, C.; Van Oyen, H. et al

in Preventive Medicine (2009)

Objective Cervical cancer screening by surveys overestimate coverage because of selection and reporting biases. Methods The prepared Inter-Mutualistic Agency dataset has about 13 million records from Pap ... [more ▼]

Objective Cervical cancer screening by surveys overestimate coverage because of selection and reporting biases. Methods The prepared Inter-Mutualistic Agency dataset has about 13 million records from Pap smears, colposcopies, cervical biopsies and surgery, performed in Belgium between 1996 and 2000. Cervical cancer screening coverage was defined as the proportion of the target population (women of 25–64 years) that has had a Pap smear taken within the last 3 years. Proportions and incidence rates were computed using official population data of the corresponding age group, area and calendar year. Results Cervical cancer screening coverage, in the period 1998–2000, was 59% at national level, for the target age group 25–64 years. Differences were small between the 3 regions. Variation ranged from 39% to 71%. Coverage was 64% for 25–29 year old women, 67% for those aged 30–39 years, 56% for those aged 50–54. The modal screening interval was 1 year. In the 3-year period 1998–2000, 3 million smears were taken from the 2.7 million women in the age group 25–64. Only 1.6 million women of the target group got one or more smears in that period and 1.1 million women had no smears, corresponding to an average of 1.88 smears per woman. Conclusion Coverage reached only 59%, but the number of smears used was sufficient to cover more than 100% of the target population. Structural reduction of overuse and extension of coverage is warranted. [less ▲]

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See detailTriom une: la tritherapie du pauvre ?
Garcia, M Villar; Mukeba-Tshialala, D.; Vaira, Dolorès ULg et al

in Revue Médicale de Liège (2009), 64(1), 32-6

Despite a relative global stabilization of its incidence, HIV infection remains a major threat for public health, principally in Africa where it concerns more than 22 million people and constitutes the ... [more ▼]

Despite a relative global stabilization of its incidence, HIV infection remains a major threat for public health, principally in Africa where it concerns more than 22 million people and constitutes the first cause of death on the continent. To face the emergency of the HIV/AIDS epidemics on the African continent, the primary goal is to make available to all patients free and efficient antiretroviral medications. Such a goal cannot be dissociated from large scale prevention campaigns. In 2000, Triomune, one of the first fixed dose combinations of three antiretrovirals (stavudine, lamivudine & nevirapine) was launched by the Indian drug company Cipla, specialized in the production of low cost medications. Its convenient pill burden (one pill twice a day) and its very low cost (around 30 US $ per month) make Triomune an appealing solution for the treatment of HIV/AIDS in Africa. Unfortunately, Triomune presents several drawbacks (low genetic barrier, frequent side effects) and one of its constituents is not used in Europe anymore. Other first line treatments are urgently needed. [less ▲]

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See detailDistribution of euphausiid larvae along the coast of East Antarctica in the Dumont d’Urville Sea (139–145°E) during summer 2004
Vallet, Carole; Koubbi, Philippe; Sultan, Emmanuëlle et al

in Antarctic Science (2009), 21(03), 197-207

The distribution of euphausiid larvae along the coast of Terre Adélie, Antarctica, was assessed using oblique tows of a double-framed bongo net at 38 stations during summer 2004. Larvae of Euphausia ... [more ▼]

The distribution of euphausiid larvae along the coast of Terre Adélie, Antarctica, was assessed using oblique tows of a double-framed bongo net at 38 stations during summer 2004. Larvae of Euphausia crystallorophias and Thysanoessa macrura were observed. For E. crystallorophias larvae, the calyptopis I stage was dominant along the coast, while the most commonly observed stage of T. macrura was the furcilia. The distribution of E. crystallorophias larvae were correlated with abiotic factors, including depth and sea surface salinity, whereas those of T. macrura larvae were correlated with biotic factors, especially chlorophyll a and nitrate. Developmental stages of both species increased in age from west to east in the survey area, with younger developmental stages (metanauplius and calyptopis I) in the western part of the region and older stages (calyptopis II and III and furcilia I to VI) in the eastern part near the Mertz Glacier Tongue (MGT). It is suggested that these patterns could be linked with the water circulation and wind: near the MGT gyres could concentrate all developmental stages of both species near the coast, while katabatic winds near Dumont d'Urville will promote larval advection seawards, with younger stages near the coast and older stages further offshore. [less ▲]

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See detailPolynomial approximation of aerodynamic coefficients based on the statistical description of the wind incidence
Denoël, Vincent ULg

in Probabilistic Engineering Mechanics (2009), 24(2), 179-189

In civil engineering applications, the aerodynamic coefficients are usually measured in wind tunnels for several wind incidences. The measurement results need to be linearized in order to perform the ... [more ▼]

In civil engineering applications, the aerodynamic coefficients are usually measured in wind tunnels for several wind incidences. The measurement results need to be linearized in order to perform the design of the structure. This paper justifies the use of different linearization techniques for different assessments as divergence or buffeting analysis. In this latter context, it is proposed to linearize the aerodynamic coefficient by the least-square method, using the probability density function of the wind incidence as a weighting function. First this probability density function is computed for a 2-D wind flow, as a function of the wind intensities and their correlation. Then, the comparison of results from different linearization techniques provides surprising results indicating that what is usually performed should be considered with care. [less ▲]

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See detailA 400GHz fMAX Fully Self-Aligned SiGe:C HBT Architecture
Van Huylenbroeck, Stefaan; Sibaja-Hernandez, Arturo; Venegas, Rafael et al

in IEEE Bipolar/BiCMOS Circuits and Technology Meeting, 2009 (2009)

An improved fully self-aligned SiGe:C HBT architecture featuring a single-step epitaxial collector-base process is described. An fMAX value of 400 GHz is reached by structural as well as intrinsic ... [more ▼]

An improved fully self-aligned SiGe:C HBT architecture featuring a single-step epitaxial collector-base process is described. An fMAX value of 400 GHz is reached by structural as well as intrinsic advancements made to the HBT device. [less ▲]

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See detailSpatial genetic structure in Milicia excelsa (Moraceae) indicates extensive gene dispersal in a low-density wind-pollinated tropical tree
Bizoux, Jean-Philippe ULg; Daïnou, Kasso ULg; Bourland, Nils ULg et al

in Molecular Ecology (2009), 18

In this study, we analysed spatial genetic structure (SGS) patterns and estimated dispersal distances in Milicia excelsa (Welw.) C.C. Berg (Moraceae), a threatened windpollinated dioecious African tree ... [more ▼]

In this study, we analysed spatial genetic structure (SGS) patterns and estimated dispersal distances in Milicia excelsa (Welw.) C.C. Berg (Moraceae), a threatened windpollinated dioecious African tree, with typically low density ( 10 adults ⁄km2). Eight microsatellite markers were used to type 287 individuals in four Cameroonian populations characterized by different habitats and tree densities. Differentiation among populations was very low. Two populations in more open habitat did not display any correlation between genetic relatedness and spatial distance between individuals, whereas significant SGS was detected in two populations situated under continuous forest cover. SGS was weak with a maximum Sp-statistic of 0.006, a value in the lower quartile of SGS estimates for trees in the literature. Using a stepwise approach with Bayesian clustering methods, we demonstrated that SGS resulted from isolation by distance and not colonization by different gene pools. Indirect estimates of gene dispersal distances ranged from rg = 1 to 7.1 km, one order of magnitude higher than most estimates found in the literature for tropical tree species. This result can largely be explained by life-history traits of the species. Milicia excelsa exhibits a potentially wideranging wind-mediated pollen dispersal mechanism as well as very efficient seed dispersal mediated by large frugivorous bats. Estimations of gene flow suggested no major risk of inbreeding because of reduction in population density by exploitation. Different strategy of seed collection may be required for reforestation programmes among populations with different extent of SGS. [less ▲]

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See detailFilière sucrière et valorisation des ressources au Maroc
Redani, Latifa ULg; Doukkali, M. Rachid; Lebailly, Philippe ULg

in IAV Hassan II (Ed.) Symposium international AGDUMED 2009 Agriculture durable en Méditerranée " Gestion intégrée des ressources en eau et en sol et durabilité des systèmes de cultures en zones méditerranéennes" (2009)

Accusées de non compétitives et d'une mauvaise valorisation des ressources, les cultures sucrières risquaient de disparaître du Maroc à cause de la dite politique d'ajustement structurel et de ... [more ▼]

Accusées de non compétitives et d'une mauvaise valorisation des ressources, les cultures sucrières risquaient de disparaître du Maroc à cause de la dite politique d'ajustement structurel et de libéralisation du secteur agricole. Le présente article analyse ces deux arguments et démontre qu'en plus des importantes distorsions sur le marché international, le calcul du coût des ressources intérieures ainsi que des indicateurs de valorisation des ressources donnent raison à l'Etat de n'avoir pas libéralisé totalement ces cultures et, plus particulièrement celle de la betterave à sucre. [less ▲]

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See detailGestion interdisciplinaire du problème d'ensablement des cuvettes en milieu sahélien nigérien
Tychon, Bernard ULg; Ambouta, K, J-M

in Geo-Eco-Trop (2009), 33

Niger faces the brunt of desertification in the Sahelian belt. Many national and international programs attempt to help the country fight against this serious environmental degradation. This article ... [more ▼]

Niger faces the brunt of desertification in the Sahelian belt. Many national and international programs attempt to help the country fight against this serious environmental degradation. This article relies on an inter-university targeted program (ITP) funded by the Coopération Universitaire au Développement (CUD) called "Invasion of circular lowlands (cuvettes) of south-eastern Niger by aeolian deposits: processes, impacts and means of struggle" to demonstrate the interest of an inter / multidisciplinary approach in the research of a better solution to an environmental problem as comprehensive as that of desertification. The study is focused on a specific form of desertification, which is that of silting “cuvettes”, areas of lowlands in the south-eastern Niger. Two examples illustrate the practical contribution of this type of approach. The article also shows the link between all the teams who have contributed to the results of the ITP and the development of this special issue. [less ▲]

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See detailA One-Field Discontinuous Galerkin Formulation of Non-Linear Kirchhoff-Love Shells
Noels, Ludovic ULg

Conference (2009)

Spatially-discontinuous Galerkin methods constitute a generalization of weak formulations, which allow for discontinuities of the problem unknowns in its domain interior. This is particularly appealing ... [more ▼]

Spatially-discontinuous Galerkin methods constitute a generalization of weak formulations, which allow for discontinuities of the problem unknowns in its domain interior. This is particularly appealing for problems involving high-order derivatives, since discontinuous Galerkin (DG) methods can also be seen as a means of enforcing higher-order continuity requirements. Recently, DG formulations of linear and non-linear Kirchhoff-Love shell theories have been proposed. This new one-field formulations take advantage of the weak enforcement in such a way that the displacements are the only discrete unknowns, while the C1 continuity is enforced weakly. The resulting one field formulation is a simple and efficient method to model thin structures and can be applied to various computational methods. [less ▲]

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See detailLe normal et le pathologique Compte-rendu de la table ronde des XV es Journées francophones d’électro-neuromyographie (15-17 mars 2006, Grenoble)
Labarre-Vila, Annick; Fournier, Emmanuel; Jabre, Joe F et al

in Lettre du Neurologue (La) : le Courrier du Spécialiste (2009)

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See detailEarly termination of ISRCTN45828668, a phase 1/2 prospective, randomized study of sulfasalazine for the treatment of progressing malignant gliomas in adults.
Robe, Pierre ULg; Martin, Didier ULg; Nguyen-Khac, Minh-Tuan ULg et al

in BMC Cancer (2009), 9

BACKGROUND: Sulfasalazine, a NF-kappaB and x(c)-cystine/glutamate antiport inhibitor, has demonstrated a strong antitumoral potential in preclinical models of malignant gliomas. As it presents an ... [more ▼]

BACKGROUND: Sulfasalazine, a NF-kappaB and x(c)-cystine/glutamate antiport inhibitor, has demonstrated a strong antitumoral potential in preclinical models of malignant gliomas. As it presents an excellent safety profile, we initiated a phase 1/2 clinical study of this anti-inflammatory drug for the treatment of recurrent WHO grade 3 and 4 astrocytic gliomas in adults. METHODS: 10 patients with advanced recurrent anaplastic astrocytoma (n = 2) or glioblastoma (n = 8) aged 32-62 years were recruited prior to the planned interim analysis of the study. Subjects were randomly assigned to daily doses of 1.5, 3, 4.5, or 6 grams of oral sulfasalazine, and treated until clinical or radiological evidence of disease progression or the development of serious or unbearable side effects. Primary endpoints were the evaluation of toxicities according to the CTCAE v.3.0, and the observation of radiological tumor responses based on MacDonald criteria. RESULTS: No clinical response was observed. One tumor remained stable for 2 months with sulfasalazine treatment, at the lowest daily dose of the drug. The median progression-free survival was 32 days. Side effects were common, as all patients developed grade 1-3 adverse events (mean: 7.2/patient), four patients developed grade 4 toxicity. Two patients died while on treatment or shortly after its discontinuation. CONCLUSION: Although the proper influence of sulfasalazine treatment on patient outcome was difficult to ascertain in these debilitated patients with a large tumor burden (median KPS = 50), ISRCTN45828668 was terminated after its interim analysis. This study urges to exert cautiousness in future trials of Sulfasalazine for the treatment of malignant gliomas. TRIAL REGISTRATION: Current Controlled Trials ISRCTN45828668. [less ▲]

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See detailModel calculations of the Sivers function satisfying the Burkardt sum rule
Courtoy, Aurore ULg; Scopetta, S.; Vento, V.

in Physical Review. D, Particles, Fields, Gravitation, and Cosmology (2009), 79(7),

It is shown that, at variance with previous analyses, the MIT bag model can explain the available data of the Sivers function and satisfies the Burkardt sum rule to a few percent accuracy. The agreement ... [more ▼]

It is shown that, at variance with previous analyses, the MIT bag model can explain the available data of the Sivers function and satisfies the Burkardt sum rule to a few percent accuracy. The agreement is similar to the one recently found in the constituent quark model. Therefore, these two model calculations of the Sivers function are in agreement with the present experimental and theoretical wisdom. © 2009 The American Physical Society. [less ▲]

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See detailCardiac metastasis from malignant melanoma.
Lempereur-Legros, Sophie ULg; Radermecker, Marc ULg; Soyeur, Daniel ULg et al

in Revue Médicale de Liège (2009), 64

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See detailAnalyzing the Boer-Mulders function within different quark models
Courtoy, Aurore ULg; Scopetta, S.; Vento, V.

in Physical Review. D, Particles, Fields, Gravitation, and Cosmology (2009), 80(7),

A general formalism for the evaluation of time-reversal odd parton distributions is applied here to calculate the Boer-Mulders function. The same formalism when applied to evaluate the Sivers function led ... [more ▼]

A general formalism for the evaluation of time-reversal odd parton distributions is applied here to calculate the Boer-Mulders function. The same formalism when applied to evaluate the Sivers function led to results which fulfill the Burkardt sum rule quite well. The calculation here has been performed for two different models of proton structure: a constituent quark model and the MIT bag model. In the latter case, important differences are found with respect to a previous evaluation in the same framework, a feature already encountered in the calculation of the Sivers function. The results obtained are consistent with the present wisdom, i.e., the contributions for the u and d flavors turn out to have the same sign, following the pattern suggested analyzing the model-independent features of the impact parameter dependent generalized parton distributions. It is therefore confirmed that the present approach is suitable for the analysis of time-reversal odd distribution functions. A critical comparison between the outcomes of the two models, as well as between the results of the calculations for the Sivers and Boer-Mulders functions, is also carried out. © 2009 The American Physical Society. [less ▲]

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See detailOn natural and conformally invariant quantizations
Mathonet, Pierre ULg; Radoux, Fabian ULg

in Journal of the London Mathematical Society (2009), 80(1), 256-272

The concept of conformally equivariant quantization was introduced by Duval, Lecomte and Ovsienko for manifolds endowed with flat conformal structures. They obtained results of existence and uniqueness ... [more ▼]

The concept of conformally equivariant quantization was introduced by Duval, Lecomte and Ovsienko for manifolds endowed with flat conformal structures. They obtained results of existence and uniqueness (up to normalization) of such a quantization procedure. A natural generalization of this concept is to seek for a quantization procedure, over a manifold M, that depends on a pseudo-Riemannian metric, is natural, and is invariant with respect to a conformal change of the metric. The existence of such a procedure was conjectured by P. Lecomte and proved by C. Duval and V. Ovsienko for symbols of degree at most 2 and by S. Loubon Djounga for symbols of degree 3. In two recent papers, we investigated the question of existence of projectively equivariant quantizations using the framework of Cartan connections. Here we will show how the formalism developed in these works adapts in order to deal with the conformally equivariant quantization for symbols of degree at most 3. This will allow us to easily recover earlier results on the subject. We will then show how it can be modified in order to prove the existence of conformally equivariant quantizations for symbols of degree 4. [less ▲]

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See detailMajoron emission in muon and tau decays revisited
Hirsch, M.; Vicente, Avelino ULg; Meyer, J. et al

in Physical Review. D, Particles, Fields, Gravitation, and Cosmology (2009), 79

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