Browsing
     by title


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

or enter first few letters:   
OK
Full Text
Peer Reviewed
See detailDeterminants of sickness absence duration after an occupational back injury in the Belgian population
Mazina, Déogratias; Donneau, Anne-Françoise ULg; Mairiaux, Philippe ULg

in American Journal of Industrial Medicine (2012), 55(3), 270-280

Background This study aimed at assessing factors associated to the duration of sickness absence after a back injury in the Belgian working population, with a special emphasis on cultural factors. Methods ... [more ▼]

Background This study aimed at assessing factors associated to the duration of sickness absence after a back injury in the Belgian working population, with a special emphasis on cultural factors. Methods The data were retrieved from the Belgian Fund for Work Accidents database over a three-year period (2001-2003). The population source involved all Belgian workers under a job contract in the private sector registered as compensated cases for an accident that occurred at the workplace (n=558276). From that database, all back injury cases involving a complete data set and registered during the first 6 months of each year (n= 11262) were selected and eight factors (gender, age, seniority in the current job, job category, accident regional location, enterprise size, sector of activity and accident circumstances) were analyzed in relation to the outcome variable, sick leave duration recorded as ordered time intervals between 0 day and 183-366 days. Results Sick leave duration was strongly associated in a multivariate model to age (>= 40 years: OR=2.18), blue collar job (1.55), work in building industry (1.32) and enterprise size (>100 : 0.85), and to a less extent to seniority (>10y: 0.88), and circumstance of accident (falls: 1.26). Injuries occurring in the French-speaking part of the country were associated to a longer sick leave (1.07; p=0.034). Conclusions This study shows that besides well-known risk factors, subtle cultural language-linked factors and/or regional differences in economic climate may significantly influence the length of disability period after a back injury. [less ▲]

Detailed reference viewed: 47 (16 ULg)
Full Text
Peer Reviewed
See detailDeterminants of terrestrial ecosystem carbon balance inferred from European eddy covariance flux sites
Reichstein, Markus; Papale, Dario; Valentini, Riccardo et al

in Geophysical Research Letters (2007), 34(1),

Pioneering work in the last century has resulted in a widely accepted paradigm that primary production is strongly positively related to temperature and water availability such that the northern ... [more ▼]

Pioneering work in the last century has resulted in a widely accepted paradigm that primary production is strongly positively related to temperature and water availability such that the northern hemispheric forest carbon sink may increase under conditions of global warming. However, the terrestrial carbon sink at the ecosystem level (i.e. net ecosystem productivity, NEP) depends on the net balance between gross primary productivity (GPP) and ecosystem respiration ( TER). Through an analysis of European eddy covariance flux data sets, we find that the common climate relationships for primary production do not hold for NEP. This is explained by the fact that decreases in GPP are largely compensated by parallel decreases in TER when climatic factors become more limiting. Moreover, we found overall that water availability was a significant modulator of NEP, while the multivariate effect of mean annual temperature is small and not significant. These results indicate that climate- and particularly temperature-based projections of net carbon balance may be misleading. Future research should focus on interactions between the water and carbon cycles and the effects of disturbances on the carbon balance of terrestrial ecosystems. [less ▲]

Detailed reference viewed: 33 (1 ULg)
See detailThe determinants of the Ricardian equivalence in the OECD nations
Pestieau, Pierre ULg; Perelman, Sergio ULg

in Verbon, H.; Van Winden, F. (Eds.) The Political Economy of Pubic Debt (1993)

Detailed reference viewed: 56 (0 ULg)
Full Text
Peer Reviewed
See detailThe determinants of tropical forest deciduousness: disentangling the effects of rainfall and geology in central Africa
Ouedraogo, Dakis-Yaoba ULg; Fayolle, Adeline ULg; Gourlet-Fleury, Sylvie et al

in Journal of Ecology (2016)

1. Understanding the environmental determinants of forests deciduousness i.e. proportion of deciduous trees in a forest stand, is of great importance when predicting the impact of ongoing global climate ... [more ▼]

1. Understanding the environmental determinants of forests deciduousness i.e. proportion of deciduous trees in a forest stand, is of great importance when predicting the impact of ongoing global climate change on forests. In this study, we examine (i) how forest deciduousness varies in relation to rainfall and geology, and (ii) whether the influence of geology on deciduousness could be related to differences in soil fertility and water content between geological substrates. 2. The study was conducted in mixed moist semi-deciduous forests in the northern part of the Congo basin. We modelled the response of forest deciduousness to the severity of the dry season across four contrasting geological substrates (sandstone, alluvium, metamorphic and basic rocks). For this, we combined information on forest composition at genus level based on commercial forest inventories (62 624 0.5 ha plots scattered over 6 million of ha), leaf habit, and rainfall and geological maps. We further examined whether substrates differ in soil fertility and water-holding capacity using soil data from 37 pits in an area that was, at the time, relatively unexplored. 3. Forest deciduousness increased with the severity of the dry season, and this increase strongly varied with the geological substrate. Geology was found to be three times more important than the rainfall regime in explaining the total variation in deciduousness. The four substrates differed in soil properties, with higher fertility and water-holding capacity on metamorphic and basic rocks than on sandstone and alluvium. The increase in forest deciduousness was stronger on the substrates that formed resource-rich clay soils (metamorphic and basic rocks) than on substrates that formed resource-poor sandy soils (sandstone and alluvium). 4. Synthesis. We found evidence that tropical forest deciduousness is the result of both the competitive advantage of deciduous species in climates with high rainfall seasonality, and the persistence of evergreen species on resource-poor soils. Our findings offer a clear illustration of wellknown theoretical leaf carbon economy models, explaining the patterns in the dominance of evergreen versus deciduous species. And, this large-scale assessment of the interaction between climate and geology in determining forest deciduousness may help to improve future predictions of vegetation distribution under climate change scenarios. In central Africa, forest is likely to respond differently to variation in rainfall and/or evapotranspiration depending on the geological substrate. [less ▲]

Detailed reference viewed: 25 (7 ULg)
Full Text
Peer Reviewed
See detailDeterminants of vitamin D supplementation prescription in nursing homes: a survey among general practitioners
Buckinx, Fanny ULg; Reginster, Jean-Yves ULg; Cavalier, Etienne ULg et al

in Osteoporosis International (2016), 27

Abstract Summary A total of 119 GPs participated to a survey aimed to assess the profile and determinants of vitamin D supplementation prescription in nursing homes. Among the respondent GPs, 65 (54.6 ... [more ▼]

Abstract Summary A total of 119 GPs participated to a survey aimed to assess the profile and determinants of vitamin D supplementation prescription in nursing homes. Among the respondent GPs, 65 (54.6 %) systematically prescribe vitamin D to their institutionalized patients and the 54 (45.4 %) others prescribe only sometimes. Introduction The aim of this study is to assess the profile and determinants of vitamin D supplementation prescription in nursing homes. Methods General practitioners (GPs) having at least one patient in a nursing home in Liège, Belgium, were asked to complete the survey. Results A total of 119 GPs participated in the survey. Among the respondent GPs, 65 (54.6 %) systematically prescribe vitamin D to their institutionalized patients and the 54 (45.4 %) others prescribe only sometimes. The main reasons for prescribing vitamin D cited by GPs who do so systematically are as follows: because they believe nursing home residents are mostly deficient in vitamin D status (92.1 %), because they believe that vitamin D supplementation prevents osteoporotic fractures (77.8 %), and because vitamin D supplementation is recommended by various scientific societies (38.1 %). GPs who only prescribe vitamin D supplementation in some patients mainly do so following a diagnosis of osteoporosis (82.4 %), on the basis the 25(OH)D level (78.4 %), in the case of history of fracture (54.9 %) or after a recent fracture (43.4 %). Surprisingly, 16 physicians (31.4 %) only prescribe vitamin D when they think of it. Interestingly, while 40.7% of GPs always prescribe the same dose of vitamin D, the remaining 59.3 % prescribe a dose that will mainly depend on the results of the 25(OH)D level (94.0 %), the patient’s bone health (49.3 %), or history of fracture (43.3 %). Conclusions More than half of GPs systematically prescribe vitamin D to their patients living in nursing homes. The other GPs usually prescribe vitamin D following the result of the vitamin D status or after a diagnosis of osteoporosis. [less ▲]

Detailed reference viewed: 47 (26 ULg)
Full Text
See detailLes déterminants perceptuels du résultat commercial des films
Choffray, Jean-Marie ULg; Pras, Bernard

in CERESSEC Working Paper, Groupe ESSEC PARIS (1979)

L'objet de ce document de recherche est de montrer comment une analyse rigoureuse de la manière dont les films sont perçus permet de mieux comprendre les déterminants de leur succès commercial. La méthode ... [more ▼]

L'objet de ce document de recherche est de montrer comment une analyse rigoureuse de la manière dont les films sont perçus permet de mieux comprendre les déterminants de leur succès commercial. La méthode proposée constitue une première étape dans le développement de systèmes d'aide à la conception et au développement des nouveaux films. [less ▲]

Detailed reference viewed: 19 (2 ULg)
Peer Reviewed
See detailDétermination automatique de l'ammoniaque dans le liquide du rumen par la méthode de Berthelot adaptée à l'auto-analyzer
Van Eenaeme, Christian ULg; Bienfait, Jean-Marie ULg; Lambot, Olivier et al

in Annales de Médecine Vétérinaire (1969), 113

Detailed reference viewed: 20 (1 ULg)
Full Text
See detailDetermination automatique de la taille du pas de temps pour les schémas implicites en dynamique non-linéaire
Noels, Ludovic ULg

Master's dissertation (2000)

Ce travail propose une gestion du choix de la durée du pas de temps. Pour ce faire nous choisissons d’utiliser un indicateur de l’erreur d’intégration numérique. La gestion développée s’adapte aux ... [more ▼]

Ce travail propose une gestion du choix de la durée du pas de temps. Pour ce faire nous choisissons d’utiliser un indicateur de l’erreur d’intégration numérique. La gestion développée s’adapte aux différents schémas d’intégration implicites étudiés. Elle garantit une précision sur les résultats obtenus tout en assurant un coût de calcul réduit. Cette stratégie est d’abord validée sur des cas généraux de grandes déformations afin de mettre en évidence son large domaine d’application. Ensuite, elle est validée sur des cas industriels. Pour l’étude de ces cas industriels, la nouvelle gestion du pas de temps est associée à un nouveau critère de convergence ainsi qu’à un nouveau schéma de décision de remise à jour de la matrice d’itération. L’intérêt principal de l’étude de cas industriels est leur nombre important de degrés de liberté ainsi que la variation des phénomènes physiques qui apparaissent au cours du temps. Les intérêts pratiques (gain de temps de calcul, garantie de précision et diminution du nombre de paramètres utilisateur) des nouveaux schémas sont alors clairement mis en évidence. Nous sommes ainsi parvenus à réduire fortement les temps de calcul de ces cas. [less ▲]

Detailed reference viewed: 84 (15 ULg)
Full Text
Peer Reviewed
See detailDétermination automatique de la taille du pas de temps pour les schémas implicites en dynamique non-linéaire
Noels, Ludovic ULg; Stainier, Laurent ULg; Ponthot, Jean-Philippe ULg et al

in Mécanique & Industries (2002), 3(1), 63-77

Pour les problèmes caractérisés par de fortes non-linéarités, ainsi que des phénomènes d'impacts et de contacts, une stratégie d'intégration à pas de temps variables est particulièrement intéressante. Ces ... [more ▼]

Pour les problèmes caractérisés par de fortes non-linéarités, ainsi que des phénomènes d'impacts et de contacts, une stratégie d'intégration à pas de temps variables est particulièrement intéressante. Ces phénomènes sont par exemple rencontrés lors de l'étude dynamique d'une interaction aube-carter d'un moteur d'avion, le cas le plus critique étant la perte de l'aube. Une stratégie d'intégration implicite à pas de temps constant donne rarement satisfaction du fait qu'il est pratiquement impossible de déterminer une durée de pas qui ne conduise pas à la divergence ou à un coût de calcul prohibitif. Une gestion automatique du pas de temps, qui tient compte de l'histoire récente des accélérations dans le corps considéré, est proposée. En fait, l'algorithme est basé sur la mesure de l'erreur d'intégration des équations d'équilibre. Cela permet d'intégrer correctement les phénomènes transitoires avec un pas de temps très long (en régime) ou très petit (lors de la perte d'aube), en garantissant une bonne précision en un temps de calcul raisonnable. De plus, un algorithme qui décide automatiquement de recalculer ou non, la matrice hessienne est proposé. Cet algorithme permet d'éviter un nombre important de remises à jour de cette matrice, ce qui permet de réduire le coût de calcul tout en assurant la convergence. Enfin, un critère de divergence des itérations est proposé. Afin d'illustrer l'efficacité des algorithmes développés, des simulations numériques sont présentées. Il s'agit aussi bien de problèmes académiques que de problèmes industriels (contacts aubes carter). [less ▲]

Detailed reference viewed: 192 (4 ULg)
Peer Reviewed
See detailDétermination d’isochrones en région liégeoise selon les moyens de transport individuels
Donnay, Jean-Paul ULg

in Bulletin de la Société Géographique de Liège (1983), 19

Detailed reference viewed: 8 (0 ULg)
Full Text
Peer Reviewed
See detailDétermination d'un index prédictif de la preeclampsie en préconceptionnel et propositions thérapeutiques de prévention primaire
Emonts, Patrick ULg; Seaksan, Sontera; Seidel, Laurence ULg et al

in Journal de Gynécologie, Obstétrique et Biologie de la Reproduction (2008), 37(5), 469-476

Objective To derive a prediction index based on the most salient history, laboratory and clinical parameters for identifying women at high risk of developing preeclampsia (PE) and to suggest a primary ... [more ▼]

Objective To derive a prediction index based on the most salient history, laboratory and clinical parameters for identifying women at high risk of developing preeclampsia (PE) and to suggest a primary prevention. Material and method Non-pregnant women with a history of PE (n =101) were compared to non-pregnant parous women with a history of one or more successful normotensive pregnancies (n =50) but with comparable age, gestation and parity profiles. The parameters included history and clinical examination; laboratory studies (hemostasis, coagulation, vitamins); and morphological and functional tests (cardiovascular and renal functions). Stepwise logistic regression analysis was applied to develop a three step PE prediction index based on the most discriminant parameters. Strategies to prevent PE in the high-risk group are described. Results Identification of women at high risk of PE can be done efficiently (88% sensitivity and specificity) using a predictive index based on a simple history, laboratory, clinical and functional information. Stategies to prevent PE in our high-risk group have given encouraging results during next pregnancy. Conclusion Our study gives a predictive index of PE outside of pregnancy and possibilities to do a primary prevention. [less ▲]

Detailed reference viewed: 212 (63 ULg)
Full Text
Peer Reviewed
See detailDétermination d'un rendement fromager de laboratoire en relation avec les caractéristiques chimiques de lairs de brebis.
Rondia, P.; Blecker, Christophe ULg; Romnée, Jean-Michel et al

Poster (2003, December)

Detailed reference viewed: 50 (4 ULg)
Full Text
Peer Reviewed
See detailDétermination d’une méthode d’observation et d’analyse des ensembles périurbains
De Smet, Fabian ULg

in Regards croisés sur la péri/urbanisation en Wallonie et en Europe : facteurs actifs et impacts (2006, December 08)

Detailed reference viewed: 72 (16 ULg)
See detailDetermination de l'énergie interne des ions produits en spectrométrie de masse à ionisation électrospray
Collette, Caroline ULg

Doctoral thesis (2000)

The internal energy deposited in the ions in the source of a mass spectrometer governs their fragmentation and therefore the content of the spectra, When the ionization conditions are well defined and ... [more ▼]

The internal energy deposited in the ions in the source of a mass spectrometer governs their fragmentation and therefore the content of the spectra, When the ionization conditions are well defined and reproducible, e.g. in electron impact, the elaboration of databases benefits the use of the method. In electrospray, however, the source conditions are not strictly defined. The elaboration of spectra databases therefore requires a calibration of the internal energy of the ions that is valid for all types of spectrometers, A method for the calibration of the internal energy of ions in electrospray is presented, developed using the fragmentation reactions of a set of probe ions (benzylpyridinium salts) under various conditions. The influence of the experimental conditions on the internal energy of the ions permits the calibration of individual working conditions [less ▲]

Detailed reference viewed: 37 (5 ULg)