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See detailImpact of benevolent sexism on assessment of dangerousness by novice and expert policemen: a study by eye tracking
Blavier, Adelaïde ULg; Cardyn, Perrine; Gelon, Emilie et al

Conference (2013, May 28)

Our aim was to study how professional expertise may influence both visual perception of a scene and verbal judgment and how these 2 components interact and are influenced by benevolent sexism attitude. We ... [more ▼]

Our aim was to study how professional expertise may influence both visual perception of a scene and verbal judgment and how these 2 components interact and are influenced by benevolent sexism attitude. We studied how stereotype (here, benevolent sexism) influences both the eye movements and the verbal judgment according to the expertise. 3 groups of subjects (10 expert policemen-policewomen, 10 novice policemen-policewomen and 10 control subjects) answered to ASI questionnaire and assessed dangerousness of 15 images of domestic violence (individually and randomly presented). Eye movements were recorded while subjects looked at the domestic violence images. Our results showed the more benevolent sexist are the subjects (particularly the women), the more they looked at the victim and the lower they assessed the dangerousness. Moreover, novices answered more slowly and assessed ambiguous situations as more dangerous than experts. The differences between novices and experts were more important for women than for men, suggesting that professional experience has a stronger impact on women than men. Our findings confirm our main hypothesis suggesting sexism influences the visual analysis of a scene and thus the judgment attributed to the scene. Moreover, it seems professional experience does not modify the stereotype, particularly for benevolent sexist men. The discussion of all our results emphasizes their implication for a better understanding of our visual cognitive system (particularly the interaction between low-level visual analysis by eye movements and verbal judgment) and for the training of policemen (by taking into account the importance of their stereotype in complex interventions). [less ▲]

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See detailImpact of biotechnology on animal breeding and genetic progress
Gengler, Nicolas ULg; Druet, Tom ULg

in Renaville, Robert; Burny, Arsène (Eds.) Biotechnology in Animal Husbandry (2001)

Animal breeding is a field related to a whole range of biotechnologies. The impact of a biotechnology can be measured by the influence it has on genetic progress. According to the type of biotechnology ... [more ▼]

Animal breeding is a field related to a whole range of biotechnologies. The impact of a biotechnology can be measured by the influence it has on genetic progress. According to the type of biotechnology considered, different component of genetic progress may be affected: accuracy of prediction, generation interval, intensity of selection and genetic variance. The first type of biotechnologies affects the efficiency of male and female reproduction: artificial insemination, multiple ovulation, in-vitro-fertilization, ova pick-up, embryo-transfer, twining, sexing of semen and embryos cloning and selfing. The impact of these technologies is mainly in the enhanced distribution of superior germplasm and the selection intensity, but also in the accuracy obtained when testing animals. In the past, artificial insemination has been a very successful biotechnology, enhancing greatly the genetic progress. A secondary, negative, impact is that these biotechnologies affect indirectly genetic diversity and therefore reduce genetic variance. A second group of biotechnologies can improve determination of the genetic merit of animals. These are all the techniques relate to quantitative or economical trait loci (QTL/ETL), their detection and use. Their main feature is the early availability in life, therefore allowing an earlier and more accurate selection. Two direction of research exists: detection of markers for the unknown QTL and direct use of a potential candidate genes as QTL/ETL. QTL/ETL will have a major impact on animal breeding especially if their use in future breeding programs can be optimized. A last type of biotechnologies with a large potential to affect animal breeding in the future are those with the ability to transform artificially DNA. The impact of these technologies is however still no very clear especially as gene expression and other issues remain unsolved. Biotechnology had, has and will have a major impact on animal breeding and genetic progress. To a certain extend animal breeding is a very promising field to use biotechnology as the past has already proven. [less ▲]

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See detailImpact of blindness onset on the functional organization and the connectivity of the occipital cortex
Collignon, Olivier; Dormal, Giulia; Albouy, Geneviève et al

in Brain : A Journal of Neurology (2013)

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See detailThe impact of blue light on non-visual brain functions changes with age
Daneault*; Vandewalle*, Gilles ULg; Hébert, M et al

in NeuroImage (2011), 56(Suppl. 1),

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See detailImpact of bone marker feedback on adherence to once monthly ibandronate for osteoporosis among Asian postmenopausal women
Kung, Annie Wai-Chee; Rachman, A Ichramsjah; Adam, MF John et al

in International Journal of Rheumatic Diseases (2009), 12

Aim: This study assesses the impact of serum carboxy-terminal collagen crosslinks (CTX) bone marker feedback (BMF) on adherence to ibandronate treatment in Asian postmenopausal women with osteoporosis ... [more ▼]

Aim: This study assesses the impact of serum carboxy-terminal collagen crosslinks (CTX) bone marker feedback (BMF) on adherence to ibandronate treatment in Asian postmenopausal women with osteoporosis. Methods: This was a 12-month (6-monthly phased), randomized, prospective, open-label, multi-center study conducted in 596 (of 628 enrolled) postmenopausal women with osteoporosis (£ 85 years old) who were naı¨ve, lapsed, or current bisphosphonate users. Patients were randomized into two arms: serum CTX BMF at 3 months versus no-BMF. Once-monthly 150 mg ibandronate tablet was administered for 12 months and adherence to therapy was assessed at 6 and 12 months. In addition, patient satisfaction and safety of ibandronate treatment were also assessed. Results: Serum CTX BMF at 3 months showed no impact on adherence. The proportions of adherent patients were comparable in the BMF versus no-BMF arms (92.6% vs. 96.0%, P = 0.16); overall, serum CTX levels were similar for adherent and non-adherent patients. However, BMF patients felt more informed about their osteoporosis (P < 0.001) and more satisfied (P < 0.01) than no-BMF patients. Conclusions: The Asian postmenopausal osteoporosis patients in this study had a high adherence rate to once-monthly ibandronate therapy. Use of serum CTX BMF had no further impact on increasing adherence, but increased treatment satisfaction. [less ▲]

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See detailImpact of bone marrow lesion on the progression of knee osteoarthritis in the SEKOIA study
Parsons, C; Edwards, MH; Bruyère, Olivier ULg et al

in Rheumatology (2014), 53(1), 130

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See detailImpact of bone marrow lesion on the progression of knee osteoarthritis in the Sekoia study
Parsons, C; Edwards, MH; Bruyère, Olivier ULg et al

in Osteoporosis International (2014), 25(2), 142

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See detailImpact of bone marrow-derived mesenchymal stromal cells on experimental xenogeneic graft-versus-host disease
Bruck, France; Belle, Ludovic ULg; LECHANTEUR, Chantal ULg et al

in Cytotherapy (2013), 15(3), 267-279

Background aims. Graft-versus-host disease (GVHD) is a life-threatening complication of allogeneic hematopoietic cell transplantation caused by donor T cells reacting against host tissues. Previous ... [more ▼]

Background aims. Graft-versus-host disease (GVHD) is a life-threatening complication of allogeneic hematopoietic cell transplantation caused by donor T cells reacting against host tissues. Previous studies have suggested that mesenchymal stromal cells (MSCs) could exert potent immunosuppressive effects. Methods. The ability of human bone marrow derived MSCs to prevent xenogeneic GVHD in non-obese diabetic/severe combined immunodeficient (NOD/SCID) mice and in NOD/SCID/interleukin-2Rg(null) (NSG) mice transplanted with human peripheral blood mononuclear cells (PBMCs) was assessed. Results. Injection of 200 106 human PBMCs intraperitoneally (IP) into sub-lethally (3.0 Gy) irradiated NOD/SCID mice also given anti-asialo GM1 antibodies IP 1 day prior and 8 days after transplantation induced lethal xenogeneic GVHD in all tested mice. Co-injection of 2 106 MSCs IP on day 0 did not prevent lethal xenogeneic GVHD induced by injection of human PBMCs. Similarly, injection of 30 106 human PBMCs IP into sub-lethally (2.5 Gy) irradiated NSG mice induced a lethal xenogeneic GVHD in all tested mice. Injection of 3 106 MSCs IP on days 0, 7, 14 and 21 did not prevent lethal xenogeneic GVHD induced by injection of human PBMCs. Conclusions. Injection of MSCs did not prevent xenogeneic GVHD in these two humanized mice models. [less ▲]

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See detailThe impact of brand pages on brand page commitment and brand commitment in the context of social networking sites
Brandt, Céline ULg; Dessart, Laurence; Pahud de Mortanges, Charles ULg

Conference (2011, March)

This study is an investigation of the impact of brand pages on Social Networking Sites (SNS) in the creation of brand commitment. The main determinants of brand page commitment are evaluated before ... [more ▼]

This study is an investigation of the impact of brand pages on Social Networking Sites (SNS) in the creation of brand commitment. The main determinants of brand page commitment are evaluated before assessing its impact on brand commitment. Subsequently, some of the potential consequences of brand commitment are assessed. The empirical part of the study was conducted in collaboration with Netlog, the first European SNS. A questionnaire assessing the 9 variables of the model was answered by a sample of 250 Netlogers. The results show that the main determinants of brand page commitment are the freedom to express on the brand page and the recognition for contributing to it. Furthermore, the study revealed a favorable impact of brand page commitment on brand commitment. The two validated consequences of brand commitment in such a context are the intention to generate positive word-of-mouth about the brand and the willingness to co-produce. [less ▲]

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See detailImpact of cell discard strategies on TCP/IP in ATM UBR networks
Rosolen, Vincent; Bonaventure, Olivier; Leduc, Guy ULg

in Performance Modelling and Evaluation of ATM Networks (1998, July)

In ATM UBR networks supporting TCP traffic, optimal efficiency can only be envisaged if switches adopt a discard mechanism that operates at the packet level rather than the cell level. In this paper, we ... [more ▼]

In ATM UBR networks supporting TCP traffic, optimal efficiency can only be envisaged if switches adopt a discard mechanism that operates at the packet level rather than the cell level. In this paper, we investigate the performance of the EPD, RED and FBA strategies by means of simulation, and give comparative results with respect to different environments and performance criteria. We show that implementing such a strategy in a LAN brings little added value, while the benefit is more obvious in a WAN access network with asymmetrical bandwidths. Specifically, the improvement not only concerns goodput but also fairness among competing TCP connections, and depends upon the Maximum Segment Size used by the sources. [less ▲]

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See detailThe Impact of Children’s Illness Perceptions on Paediatric Cancer Patients’ Quality of Life
Fonseca, Marta; Missotten, Pierre ULg; Etienne, Anne-Marie ULg et al

in Psycho-oncology (2010), 19(Suppl. 2), 126

Purpose The study of children’s illness perceptions has been widely developed over de last decade (Chateaux, 2005). More recently research has focussed on the impact of illness perceptions on Quality of ... [more ▼]

Purpose The study of children’s illness perceptions has been widely developed over de last decade (Chateaux, 2005). More recently research has focussed on the impact of illness perceptions on Quality of Life (QoL). The present communication aims to analyse the impact of illness perceptions of children with cancer on Generic and Modular QoL. Authors put forward the hypothesis that the several dimensions of children’s illness perceptions may influence QoL in different ways. Methods The Brief Illness Perception Questionnaire (Broadbent et al.,2006) and the Quality of Life Systemic Inventory for Children - Module for Cancer (Missotten et al., 2008) were administered to 40 children with cancer, aged from 8 to 12 years, at a paediatric hospital. Specifically developed for children from these ages, the QoL measure is a self-assessment questionnaire that provides a general and a modular score (general domains of QoL and domains of QoL related with cancer). Results Multiple regressions highlighted that five dimensions of children’s cancer perceptions are significant predictors of QoL, namely illness “consequences”, “identity”, “concerns”, “coherence” and “timeline”. The most predictable dimension of both general and modular QoL is “cancer consequences”: it explains 36% (Beta=.51; p=.01) of the general and 47% (Beta=.70; p=.01) of the modular QoL variance. Children reporting a less threatening view about the consequences of cancer in their lives reveal a better QoL. Conclusions The framework of the present study has its fundamentals on recent literature developments by presenting a modular approach to QoL assessment. Results revealed that illness perceptions of children with cancer play an important role both on general QoL and QoL more directly related with cancer and treatments. Through the analysis of the influence of cancer perceptions on QoL, findings provide information to design intervention to promote QoL among paediatric cancer patients. [less ▲]

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See detailImpact of chondroitin sulphate on health utility in patients with knee osteoarthritis: towards economic analysis.
Bruyère, Olivier ULg; Scholtissen, S.; Neuprez, Audrey et al

in Journal of Medical Economics (2009), 12(4), 356-360

Abstract Objectives: The first objective was to assess the effect of the chondroitin 4 and 6 sulphate (CS) on health-related quality of life using utility values in patients with knee osteoarthritis (OA ... [more ▼]

Abstract Objectives: The first objective was to assess the effect of the chondroitin 4 and 6 sulphate (CS) on health-related quality of life using utility values in patients with knee osteoarthritis (OA) during a 24-month treatment course. The second objective was, using these data, to conduct economic analyses. Methods: Data from the STOPP study was used. This study was a randomised, double-blind, placebo (PL) -controlled trial of 2-year duration. In the STOPP study, authors assessed quality of life using the Western Ontario and McMaster Osteoarthritis Index (WOMAC). WOMAC scores were translated into Health Utility Index (HUI) scores using a specific formula. Incremental cost effectiveness ratio (ICER) was calculated taking into account the cost of CS and its effect on HUI scores, compared to PL. Results: At baseline, the mean (SD) HUI scores were 0.59 (0.17), and 0.59 (0.18) for the PL and CS groups, respectively (p=0.31 between the two groups). The mean (SD) HUI scores changes from baseline to 6 months were 0.02 (0.02), and 0.05 (0.01) for the PL and CS groups, respectively (p=0.03). After 24 months of follow-up, HUI score increases by 0.04 (0.02) in the PL group and by 0.05 (0.02) in the CS group (p=0.37). Using the price bracket of CS in Europe, ICER assessment always resulted in a cost below euro30,000 per QALY gained, after 6, 12 and 24 months of treatment. Conclusion: CS treatment increases health utilities in patients with knee OA compared to PL over the first 6 months of treatment. Economic evaluation based on these data suggests that CS treatment could be considered as cost-effective in patients with knee OA up to a period of 24 months. A limitation in this study is the absence of direct utility assessment as well as the absence of effective treatment as comparator. [less ▲]

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See detailImpact of chronic cadmium exposure at environmental dose on escape behaviour in sea bass (Dicentrarchus labrax L.; Teleostei, Moronidae).
Faucher, Karine ULg; Fichet, Denis; Miramand, Pierre et al

in Environmental Pollution (2008), 151(1), 148-57

The effect of chronic exposure to a low concentration (0.5 microg l(-1)) of cadmium ions was investigated on escape behaviour of sea bass, Dicentrarchus labrax, using video analysis. Observations were ... [more ▼]

The effect of chronic exposure to a low concentration (0.5 microg l(-1)) of cadmium ions was investigated on escape behaviour of sea bass, Dicentrarchus labrax, using video analysis. Observations were also performed on the microanatomy of lateral system neuromasts. When fish were exposed for 4h per day over 8 days to the cadmium ions, most of both types of neuromasts observed remained intact. However, some of them presented damaged sensory maculae. Whereas before cadmium exposure, fish responded positively to nearly all the lateral system stimulations, after exposure they decreased by about 10% their positive responses to stimulations. From the 15th day after the beginning of cadmium exposure, neuromasts presented progressively less damage, cadmium accumulation in gills and scales decreased significantly and fish escape behaviour had recovered. This study presents a new concept in ecotoxicology: using behavioural change to reveal the effects of pollution levels, scarcely detectable by currently used techniques (physiological responses). [less ▲]

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See detailImpact of chronic graft-versus-host disease (GVHD) after reduced intensity conditioning (RIC) allogeneic stem cell transplantation (allo-SCT) as treatment for acute myeloid leukemia (AML) : a survey from the Acute Leukemia Working Party of the EBMT
Baron, Frédéric ULg; Labopin, Myriam; Niederwieser, Dietger et al

in Blood (2011), 118

The goal of RIC allo-SCT is to harness the graft-versus-leukemia (GVL) effect, while minimizing toxicities and the risk of GVHD. However, prior studies have shown a lower risk of relapse in AML patients ... [more ▼]

The goal of RIC allo-SCT is to harness the graft-versus-leukemia (GVL) effect, while minimizing toxicities and the risk of GVHD. However, prior studies have shown a lower risk of relapse in AML patients (pts) who experienced chronic GVHD after RIC allo-SCT versus in those who did not. Here, we investigated the impact of occurrence of GVHD on transplantation outcomes in a large cohort of AML pts given allogeneic PBSC after RIC conditioning. Data from 1859 AML pts in first (n=1439) or second (n=420) CR transplanted between 2000 and 2009 following a RIC regimen at EBMT affiliated centres were analyzed. Pts were given PBSC from HLA-identical sibling (MRD, n=1208), or from HLA-matched unrelated donors (MUD, n=651). Median pt age at transplantation was 56 y (range, 18–77). 338 male pts were given grafts from female donors. RIC was based on low-dose TBI in 520 (28%) pts, while the remaining pts received chemotherapy-based RIC. ATG was given in 269 (22%) MRD and in 267 (41%) MUD recipients, respectively, while 151 (13%) MRD and 165 (25%) MUD recipients received in-vivo T cell depletion with alemtuzumab. The impact of chronic GVHD on relapse risk, non-relapse mortality (NRM), leukemia-free survival (LFS), and overall survival (OS) was assessed using time-dependent multivariate Cox models and in a landmark analysis at 18 months after transplant. Three-year incidences of relapse, NRM, LFS and OS were 34±1%, 15±1%, 51±2% and 60±2% in MRD recipients, respectively, and 34±2% (p=NS), 24±2% (P<0.001), 42±2% (P=0.001) and 47±2% (P=0.001) in MUD recipients, respectively. Grade II, III and IV acute GVHD were observed in 133 (11%), 61 (5%) and 30 (2%) MRD recipients and in 119 (18%), 41 (6%) and 24 (4%) MUD recipients, respectively. The 3-y cumulative incidence of chronic GVHD was 47%. Fifty-three percent of patients with chronic GVHD had extensive chronic GVHD, while the remaining 47% had limited chronic GVHD. In multivariate analyses, occurrence of grade II-IV acute GVHD was associated with a lower risk of relapse (HR=0.8; P=0.04), a higher risk of chronic (HR=2.2; P<0.001) and extensive chronic GVHD (HR=2.8; P<0.001), a higher risk of NRM (HR=2.4 P<0.001), a worsened LFS (HR=1.3; P=0.01), and a worsened OS (HR=1.5; P<0.001). In multivariate time-dependent analyses, occurrence of limited chronic GVHD was associated with a lower risk of relapse (HR=0.7; P=0.05), comparable NRM (HR=1.4; P=0.16), comparable LFS (HR=0.9; P=0.29) and better OS (HR=0.5; P<0.001), while occurrence of extensive chronic GVHD was associated with a lower risk of relapse (HR=0.6; P=0.01), higher NRM (HR=3.2; P<0.001), a trend for worsened LFS (HR=1.3; P=0.06) and comparable OS (HR=0.9; P=0.34). The median interval from transplantation to occurrence of chronic GVHD was 163 (range, 100–1545) days. To further assess the graft-versus-leukemia effect of chronic GVHD, we performed a landmark analysis in patients who were leukemia-free at 18 months after transplantation (n=776). Median follow-up from this landmark time-point was 24 (range, 0.1–112) months. Two-year relapse, NRM, LFS and OS were 16±2%, 2.5±1%, 82±2%, and 89±2%, respectively, in patients without chronic GVHD before the landmark time-point, versus 9±1% (P=0.001), 8±1% (P<0.001), 83±2% (P=0.65), and 86±2% (P=0.38), respectively, in patients with chronic GVHD before the landmark time-point.In conclusion, in this cohort of AML patients transplanted in remission, occurrence of chronic GVHD was associated with a lower risk of relapse that translated to better OS in patients with limited chronic GVHD but not in those with extensive chronic GVHD who experienced higher long term NRM, highlighting the need for long term prospective assessment of long term effects and quality of life in patients receiving RIC allo-SCT. [less ▲]

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See detailImpact of chronic graft-versus-host disease after reduced-intensity conditioning allogeneic stem cell transplantation for acute myeloid leukaemia: A report from the Acute Leukaemia Working Party of the European Group for Blood and Marrow Transplantation
Baron, Frédéric ULg; Labopin, M.; Niederwieser, D. et al

Conference (2012)

We investigated the impact of occurrence of GVHD on transplantation outcomes in a large cohort of AML pts given allogeneic PBSC after RIC conditioning. Data from 1859 AML pts in fi rst (n=1439) or second ... [more ▼]

We investigated the impact of occurrence of GVHD on transplantation outcomes in a large cohort of AML pts given allogeneic PBSC after RIC conditioning. Data from 1859 AML pts in fi rst (n=1439) or second (n=420) CR transplanted between 2000 and 2009 following a RIC regimen at EBMT affi liated centres were analyzed. Pts were given PBSC from HLA-identical sibling (MRD, n=1208), or from HLA-matched unrelated donors (MUD, n=651). ATG was given in 269 (22%) MRD and in 267 (41%) MUD recipients, respectively, while 151 (13%) MRD and 165 (25%) MUD recipients received in-vivo T cell depletion with alemtuzumab. The impact of chronic GVHD (cGVHD) on outcomes was assessed using time-dependent multivariate Cox models and in a landmark analysis at 18 months after transplant. The 3-y cumulative incidence of cGVHD was 47%. Fifty-three percent of patients with cGVHD had extensive cGVHD, while the remaining 47% had limited cGVHD. In multivariate analyses, occurrence of grade II-IV aGVHD was associated with a lower risk of relapse (HR=0.8; P=0.04), a higher risk of chronic (HR=2.2; P<0.001) and extensive chronic GVHD (HR=2.8; P<0.001), a higher risk of NRM (HR=2.4 P<0.001), a worsened LFS (HR=1.3; P=0.01), and a worsened OS (HR=1.5; P<0.001). In multivariate time-dependent analyses, occurrence of limited cGVHD was associated with a lower risk of relapse (HR=0.7; P=0.05), comparable NRM (HR=1.4; P=0.16), comparable LFS (HR=0.9; P=0.29) and better OS (HR=0.5; P<0.001), while occurrence of extensive cGVHD was associated with a lower risk of relapse (HR=0.6; P=0.01), higher NRM (HR=3.2; P<0.001), a trend for worsened LFS (HR=1.3; P=0.06) and comparable OS (HR=0.9; P=0.34). In a landmark analysis in patients who were leukemia-free at 18 months after transplantation (n=776), 2-year relapse, NRM, LFS and OS were 16±2%, 2.5±1%, 82±2%, and 89±2%, respectively, in patients without cGVHD before the landmark time-point, versus 9±1% (P=0.001), 8±1% (P<0.001), 83±2% (P=0.65), and 86±2% (P=0.38), respectively, in patients with cGVHD before the landmark time-point. In conclusion, in this cohort of AML patients transplanted in remission, occurrence of cGVHD was associated with a lower risk of relapse that translated to better OS in patients with limited cGVHD but not in those with extensive cGVHD who experienced higher long term NRM. These results highlight the role of the GVT effect in RIC allo-SCT, but also the need for improving the prevention of severe cGVHD in pts receiving RIC allo-SCT. [less ▲]

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See detailImpact of circulation on export production, dissolved organic matter, and dissolved oxygen in the ocean: Results from Phase II of the Ocean Carbon-cycle Model Intercomparison Project (OCMIP-2)
Najjar, R. G.; Jin, X.; Louanchi, F. et al

in Global Biogeochemical Cycles (2007), 21(3),

Results are presented of export production, dissolved organic matter (DOM) and dissolved oxygen simulated by 12 global ocean models participating in the second phase of the Ocean Carbon-cycle Model ... [more ▼]

Results are presented of export production, dissolved organic matter (DOM) and dissolved oxygen simulated by 12 global ocean models participating in the second phase of the Ocean Carbon-cycle Model Intercomparison Project. A common, simple biogeochemical model is utilized in different coarse-resolution ocean circulation models. The model mean (+/- 1 sigma) downward flux of organic matter across 75 m depth is 17 +/- 6 Pg C yr(-1). Model means of globally averaged particle export, the fraction of total export in dissolved form, surface semilabile dissolved organic carbon (DOC), and seasonal net outgassing (SNO) of oxygen are in good agreement with observation-based estimates, but particle export and surface DOC are too high in the tropics. There is a high sensitivity of the results to circulation, as evidenced by (1) the correlation of surface DOC and export with circulation metrics, including chlorofluorocarbon inventory and deep-ocean radiocarbon, (2) very large intermodel differences in Southern Ocean export, and (3) greater export production, fraction of export as DOM, and SNO in models with explicit mixed layer physics. However, deep-ocean oxygen, which varies widely among the models, is poorly correlated with other model indices. Cross-model means of several biogeochemical metrics show better agreement with observation-based estimates when restricted to those models that best simulate deep-ocean radiocarbon. Overall, the results emphasize the importance of physical processes in marine biogeochemical modeling and suggest that the development of circulation models can be accelerated by evaluating them with marine biogeochemical metrics. [less ▲]

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See detailImpact of climate and carbon sensitivities on the North Pacific ventilation in an Earth system model
Mouchet, Anne ULg; Menviel, Laurie; Goosse, Hugues et al

Conference (2011, May)

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See detailImpact of climate change on groundwater reserves
Goderniaux, Pascal ULg

Doctoral thesis (2010)

Estimating the impacts of climate change on groundwater represents one of the most difficult challenges faced by water resources specialists. One difficulty is that simplifying the representation of the ... [more ▼]

Estimating the impacts of climate change on groundwater represents one of the most difficult challenges faced by water resources specialists. One difficulty is that simplifying the representation of the hydrological system, or using too simple climate change scenarios often leads to discrepancies in projections. Additionally, these projections are affected by uncertainties from various sources, and these uncertainties are not evaluated in previous studies. In this context, the objective of this study is to provide an improved methodology for the estimation of climate change impact on groundwater reserves, including the evaluation of uncertainties. This methodology is applied to the case of the Geer basin catchment (480 km²) in Belgium. A physically-based surface-subsurface flow model has been developed for the Geer basin with the finite element model HydroGeoSphere. The simultaneous solution of surface and subsurface flow equations in HydroGeoSphere, as well as the internal calculation of the actual evapotranspiration as a function of the soil moisture at each node of the defined evaporative zone, improve the representation and calibration of interdependent processes like recharge, which is crucial in the context of climate change. Fully-integrated surface-subsurface flow models have recently gained attention, but have not been used in the context of climate change impact studies. This surface-subsurface flow model is combined with advanced climate change scenarios for the Geer basin. Climate change simulations were obtained from six regional climate model (RCM) scenarios assuming the SRES A2 greenhouse gases emission (medium-high) scenario. These RCM scenarios were statistically downscaled using two different methods: the 'Quantile Mapping Biased Correction' technique and a 'Weather Generator' technique. Both of them are part of the most advanced downscaling techniques. They are able to apply corrections not only to the mean of climatic variables, but also across the statistical distributions of these variables. This is important as these distributions are expected to change in the future, with more violent rainfall events, separated by longer dry periods. The 'quantile mapping bias-correction' technique generate climate change time series representative of a stationary climate for the periods 2011-2040, 2041-2070 and 2071-2100. The 'CRU' weather generator is used to generate a large number of equiprobable scenarios simulating full transient climate change between 2010 and 2085. All these scenarios are applied as input of the Geer basin model. The uncertainty is evaluated from different possible sources. Using a multi-model ensemble of RCMs and GCMs enables to evaluate the uncertainty linked to climatic models. The application of a large number of equiprobable climate change scenarios, generated with the 'weather generator', as input of the hydrological model allows assessing the uncertainty linked to the natural variability of the weather. Finally, the uncertainty linked to the calibration of the hydrological model is evaluated using the computer code 'UCODE_2005'. The climate change scenarios for the Geer basin model predict hotter and drier summers and warmer and wetter winters. Considering the results of this study, it is very likely that groundwater levels and surface flow rates in the Geer basin will decrease. This is of concern because it also means that groundwater quantities available for abstraction will also decrease. However, this study also shows that the uncertainty surrounding these projections is relatively large and that it remains difficult to state on the intensity of the decrease. [less ▲]

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