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See detailFactors affecting hematopoietic recovery after autologous peripheral blood progenitof-cell transplantation in aggressive non-Hodgkin's lymphoma : a prospective study of 123 patients
Langouet, Anne-Marie; Brice, Pauline; Simon, Danielle et al

in Hematology Journal : The Official Journal of the European Haematology Association (2001), 2

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See detailFactors Affecting Plasma Pregnancy-associated Glycoprotein 1 Concentrations Throughout Gestation in High-producing Dairy Cows.
Serrano, B.; Lopez-Gatius, F.; Santolaria, P. et al

in Reproduction in Domestic Animals (2009), 44(4), 600-605

This study was designed to establish the factors, if any, which could affect plasma pregnancy-associated glycoprotein-1 (PAG-1) expression in a study population of 87 pregnant, high-producing dairy cows ... [more ▼]

This study was designed to establish the factors, if any, which could affect plasma pregnancy-associated glycoprotein-1 (PAG-1) expression in a study population of 87 pregnant, high-producing dairy cows. The factors examined were: semen providing breed (Holstein-Friesian vs Limousin), outcome of gestation (male vs female newborn, and singleton vs twin pregnancies), lactation number, milk production at pregnancy diagnosis, plasma progesterone concentration, season of gestation (warm period, March-November vs cool period, December-February), and day of gestation (40, 90, 120, 150, 180 and 210). Pregnancy was diagnosed by transrectal ultrasound on day 40 post-insemination and by palpation per rectum on days 90, 120, 150, 180 and 210. Blood samples were collected from each animal immediately before each pregnancy diagnosis. The relative contributions of the different factors on PAG-1 concentrations were evaluated by GLM repeated measures analysis of variance. No significant effects of the herd, foetal sex, milk production, lactation number and plasma progesterone concentrations were observed. In contrast, twin pregnancy, the use of Limousin semen and conception during the cool period were correlated with significantly increased plasma PAG-1 concentrations throughout gestation. Our data indicate that both cow well-being during early placental development, determined in our conditions by reduced heat stress when conception occurred in the cool season, and crossbreed pregnancies lead to improved PAG-1 production throughout the gestation period. [less ▲]

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See detailFactors affecting plasma progesterone in the early fetal period in high producing dairy cows.
Bech-Sabat, G.; Lopez-Gatius, F.; Yaniz, J. L. et al

in Theriogenology (2008), 69(4), 426-32

The aim of the present study was to determine whether certain animal- or management related factors could affect plasma progesterone concentrations on Day 42 of gestation in high producing dairy cows ... [more ▼]

The aim of the present study was to determine whether certain animal- or management related factors could affect plasma progesterone concentrations on Day 42 of gestation in high producing dairy cows. Factors affecting early fetal loss were also analyzed. The study population was comprised of 199 pregnant cows classified as having high (> or =9 ng/ml) or low (<9 ng/ml) plasma progesterone concentrations. Through logistic regression procedures it was determined that, based on the odds ratio, cows with two or more corpora lutea were three times more likely to have high progesterone concentrations than cows with a single corpus luteum. Low producing cows during the warm season were 2.86 times more likely to have high progesterone concentrations than the remaining cows. Primiparous cows with high concentrations (>4 ng/ml) of pregnancy associated glycoprotein-1 (PAG-1) were 2.73 times more likely to have high progesterone concentrations than the remaining cows. Of the 199 pregnancies, 25 (12.6%) suffered early fetal loss: 22/136 (16.2%) during the warm season and 3/63 (4.8%) during the cool season, all in cows without additional corpora lutea. Based upon the odds ratio, cows without an additional corpus luteum were 3.67 times more likely to suffer fetal loss during the warm season than during the cool season. Our results indicate that milk production, the presence of two or more corpora lutea and plasma PAG-1 concentrations can affect plasma progesterone concentrations at the onset of the fetal period. The presence of an additional corpus luteum strongly diminished the risk of early fetal loss during the warm period. [less ▲]

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See detailFactors affecting plasma prolactin concentrations throughout gestation in high producing dairy cows.
Garcia-Ispierto, I.; Lopez-Gatius, F.; Almeria, S. et al

in Domestic Animal Endocrinology (2009), 36(2), 57-66

The aim of the present study was to investigate possible relationships between plasma concentrations of prolactin and the following factors throughout gestation in lactating dairy cows: photoperiod ... [more ▼]

The aim of the present study was to investigate possible relationships between plasma concentrations of prolactin and the following factors throughout gestation in lactating dairy cows: photoperiod, season, milk production, Neospora caninum-seropositivity, twin pregnancy, and plasma concentrations of pregnancy associated glycoproteins-1 (PAG-1), progesterone and cortisol. Pregnancy was diagnosed by trans-rectal ultrasonography on Day 40 post-insemination and by palpation per rectum on Days 90, 120, 150, 180 and 210 or until abortion in aborting cows. Blood samples were collected from each animal immediately before each pregnancy diagnosis. The study population was comprised of 73 non-aborting (54 Neospora-seropositive cows) and 20 aborting cows (all Neospora-seropositive) cows. In non-aborting cows, GLM repeated measures of analysis of variance revealed that lactation number and days in milk had no effect on plasma prolactin concentrations throughout gestation, whereas high plasma prolactin concentrations were significantly associated with high plasma levels of cortisol and PAG-1, with Neospora-seropositivity, positive photoperiod (increasing day length), twin pregnancy, and with low plasma progesterone concentrations. An interaction among plasma prolactin, plasma cortisol and milk production was observed in that plasma prolactin concentrations differed significantly throughout gestation and were highest in high-producing cows with high cortisol levels. In Neospora-seropositive non-aborting versus aborting cows, mean prolactin concentrations failed to differ on Days 40, 90, 120, 150 and 180 of pregnancy, whereas prolactin values were significantly lower (P=0.03) in aborting animals on Day 210 of pregnancy. Our results indicate that a positive photoperiod and Neospora-infection lead to increased plasma prolactin concentrations throughout gestation. Reduced prolactin concentrations detected in Neospora-seropositive aborting cows compared to non-aborting animals suggests a protective effect of prolactin in N. caninum infection. [less ▲]

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See detailFactors Affecting Small Scale Fish Farmers in Accessing Markets: a case study of fish value chain in HaiDuong Province, Vietnam
Nguyen Van Huong, ULg; Tran Huu, Cuong; Lebailly, Philippe ULg

Conference (2016)

Traditionally, small farmers sell their crops or/and animals at the farm gate to intermediaries, often at a low price. However, innovations in marketing arrangements can transform market relations in ... [more ▼]

Traditionally, small farmers sell their crops or/and animals at the farm gate to intermediaries, often at a low price. However, innovations in marketing arrangements can transform market relations in favour of smallholders, and producer organizations are well-positioned to take advantage of these new approaches. Factor analysis was applied on twelve components of output markets in Haiduong province. The results show that there are patterns that are observable in terms of access and use of output market by fish farmers. The most commonly used output markets by aquaculture farmers are local fresh output market, the best retail produce markets as well as the wholesale fresh fish markets. The study reveals that farmers tend to sell their fish to the wholesale fresh fish markets. The best retail output markets also provide an important market outlet for produce by aquaculture farmers. Improving road conditions and transport services in the projected regions of aquaculture production as well as rural areas will not only improve accessibility of external markets, but will also improve accessibility of local output markets. [less ▲]

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See detailFactors affecting Tan Spot on winter wheat in the Grand-Duchy of Luxembourg
El Jarroudi, Moussa ULg; Kouadio, Louis; Beyer, Marco et al

in Journal of Plant Pathology [=JPP] (2013), s1

Tan spot caused by Drechslera tritici-repentis was identified for the first time in the Grand-Duchy of Luxembourg (GDL) in 1999 on the basis of morphological characters. In order to optimize disease ... [more ▼]

Tan spot caused by Drechslera tritici-repentis was identified for the first time in the Grand-Duchy of Luxembourg (GDL) in 1999 on the basis of morphological characters. In order to optimize disease control measures in this country, tillage methods, cultivar resistance, and fungicides effects were investigated during 1999-2009 in four sites. Over this period, only three years (i.e. 1999, 2000, and 2009) with epidemic outbreak were recorded. Field experiments showed a significant difference in disease severity between sites (P < 0.001), cultivars (P < 0.0001) and years (P < 0.001). In years with epidemic outbreak, the interaction of cultivars with non-inversion tillage, intensive winter wheat production, and favorable weather conditions caused an early outbreak of the disease and a significant severity at growth stage 83 (early dough). Non-inversion tillage was found to be a major factor increasing the tan spot severity compared to conventional tillage. Furthermore, the analysis revealed that the disease severity was related to the cultivar’s susceptibility. For cultivars with similar phenology, the severity differed between the cultivar with the highest and the one with ne lowest susceptibility by a factor of two to four. The study also showed that no fungicide (mix of triazoles and strobilurins) effect was observed in the epidemic years, except in 2000. [less ▲]

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See detailFactors affecting the response to the specific treatment of several forms of clinical anestrus in high producing dairy cows
Lopez-Gatius, F.; Mirzaei, A.; Santolaria, P. et al

in Theriogenology (2008), 69

This study was designed to examine estrous response rates to the therapeutic treatment of clinical anestrus in high producing dairy cows and to identify the factors that could affect these rates. Cows ... [more ▼]

This study was designed to examine estrous response rates to the therapeutic treatment of clinical anestrus in high producing dairy cows and to identify the factors that could affect these rates. Cows with silent ovulation (Subestrus group), cystic ovarian disease (Cyst group) or ovarian hypofunction (OH group) were given specific treatment for their disorder. Data were derived from 1764 treatments in cows producing a mean of 45.4 kg of milk upon treatment including: 889 subestrous cows, 367 cystic cows and 508 cows with ovarian hypofunction. Cows showing estrus following treatment exhibited a similar pregnancy rate to cows attaining natural estrus used as reference: 33% (337/1006) and 35% (626/1796), respectively. No significant ifferences in pregnancy rates were observed among the Subestrus, Cyst and OH groups (34% (196/571), 34% (44/130), 32% (97/305), respectively. Based on the odds ratio, an estrous response for all groups was less likely to occur in cows that had suffered previous anestrus, compared to cows that were anestrous for the first time, whereas the likelihood of an estrous response increased in cows treated after 90 days in milk. Our results indicate that previous anestrus and a late stage of lactation can have a negative and positive effect, respectively, on the estrous response to the specific treatment of clinical anestrus shown by high producing dairy cows. Treatment targeted at each type of clinical anestrus can render similar pregnancy rates to those shown by cows in natural estrus. [less ▲]

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See detailFactors affecting the three-dimensional distribution of exogenous zinc in a sandy Luvisol subjected to intensive irrigation with raw wastewaters.
Dere, Christelle ULg; Cornu, Sophie; Lamy, Isabelle

in Soil Use and Management (2006), 22

Massive volumes of raw wastewater have been spread on sandy Luvisols in the Paris region since 1899, causing major soil contamination with metallic trace elements (MTE). To identify the factors ... [more ▼]

Massive volumes of raw wastewater have been spread on sandy Luvisols in the Paris region since 1899, causing major soil contamination with metallic trace elements (MTE). To identify the factors influencing the vertical and horizontal redistribution of MTE at the plot scale, a study was carried out of the three-dimensional distribution of zinc. The background and exogenous fractions of zinc in the contaminated soil were discriminated using correlations between zinc and iron defined from unpolluted soils of the area. At the surface, the spatial distribution of zinc is determined by the geometry of the irrigation system and the terrain topography. The highest concentrations are observed near the irrigation outlets and in areas of very slight slope. The exogenous zinc has migrated down to the base of the studied solums (1 m depth), and its subsurface distribution depends upon the physico-chemical properties of the horizons. In the E horizon, the trapping of exogenous zinc is governed by the number of available reactive sites, whereas in the Bt horizon it is a function of the vertical and lateral behaviour of the drainage. Moreover, lateral transfer of exogenous zinc occurs in the C horizon. In the case of soil contaminated with raw wastewater, the organization of water flow on the surface and in the subsurface is a determining factor in the redistribution of zinc within a plot. [less ▲]

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See detailFactors affecting trace element content in periurban market garden subsoil in Yunnan Province, China
Zu, Yanqun; Bock, Laurent ULg; Schvartz, Christian et al

in Journal of Environmental Sciences (China) (2011), 23(3), 488-496

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See detailFactors associated with AIP expression in somatotropinomas and the possible influence of somatostatin analogues
Jaffrain-Rea, M. L.; Angelini, M.; Tichomirowa, M. et al

in European Neuroendocrine Association - Liège, 22-25 septembre 2010 (2010, September)

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See detailFactors associated with clinical inertia: an integrative review
Aujoulat, I; Jacquemin, p; Rietzschel, E et al

in Advances in Medical Education and Practice (2014), 5

Failure to initiate or intensify therapy according to evidence-based guidelines is increasingly being acknowledged as a phenomenon that contributes to inadequate management of chronic conditions, and is ... [more ▼]

Failure to initiate or intensify therapy according to evidence-based guidelines is increasingly being acknowledged as a phenomenon that contributes to inadequate management of chronic conditions, and is referred to as clinical inertia. However, the number and complexity of factors associated with the clinical reasoning that underlies the decision-making processes in medicine calls for a critical examination of the consistency of the concept. Indeed, in the absence of information on and justification of treatment decisions that were made, clinical inertia may be only apparent, and actually reflect good clinical practice. This integrative review seeks to address the factors generally associated with clinical inaction, in order to better delineate the concept of true clinical inertia. [less ▲]

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See detailFactors associated with outcomes in allogeneic hematopoietic cell transplantation with nonmyeloablative conditioning after failed myeloablative hematopoietic cell transplantation
Baron, Frédéric ULg; Storb, R.; Storer, B. E. et al

in Journal of Clinical Oncology (2006), 24(25), 4150-4157

Purpose Several studies have investigated the feasibility of allogeneic hematopoietic cell transplantations (HCTs) after reduced-intensity conditioning in patients who experienced relapse after ... [more ▼]

Purpose Several studies have investigated the feasibility of allogeneic hematopoietic cell transplantations (HCTs) after reduced-intensity conditioning in patients who experienced relapse after myeloablative HCT. Although most studies showed relatively low nonrelapse mortality (NRM) rates and encouraging short-term results, it has yet to be defined which patients would benefit most from these approaches. Patients and Methods We analyzed data from 147 patients with hematologic malignancies who experienced treatment failure with conventional autologous (n = 135), allogeneic (n = 10), or syngeneic (n = 2) HCT and were treated with HLA-matched related (n = 62) or unrelated (n = 85) grafts after conditioning with 2 Gy of total-body irradiation with or without fludarabine. Results Three-year probabilities of NRM, relapse, and overall survival were 32%, 48%, and 27%, respectively, for related recipients, and 28%, 44%, and 44%, respectively, for unrelated recipients. The best outcomes were observed in patients with non-Hodgkin's lymphoma, whereas patients with multiple myeloma and Hodgkin's disease had worse outcomes as a result of high incidences of relapse and progression. Being in partial remission (PR) or complete remission (CR) at HCT (P = .002) and developing chronic graft-versus-host disease (GVHD; P = .03) resulted in lower risks of relapse and progression. Factors associated with better overall survival were PR or CR (P = .01) and lack of comorbidity (P = .03) at HCT and absence of acute GVHD after HCT (P = .06). Conclusion Encouraging outcomes were seen with allogeneic HCT after nonmyeloablative conditioning in selected patients who had experienced relapse after a high-dose HCT, particularly in patients with non-Hodgkin's lymphoma. Results with unrelated grafts were comparable with results with related grafts. [less ▲]

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See detailFactors associated with reaching or not reaching target HbA1c after initiation of basal or premixed insulin in patients with type 2 diabetes.
Scheen, André ULg; Schmitt, H.; Jiang, H. H. et al

in Diabètes & Métabolism (2017), 43(69-78),

AIMS: To evaluate factors associated with reaching or not reaching target glycated haemoglobin (HbA1c) levels by analysing the respective contributions of fasting hyperglycaemia (FHG), also referred to as ... [more ▼]

AIMS: To evaluate factors associated with reaching or not reaching target glycated haemoglobin (HbA1c) levels by analysing the respective contributions of fasting hyperglycaemia (FHG), also referred to as basal hyperglycaemia, vs postprandial hyperglycaemia (PHG) before and after initiation of a basal or premixed insulin regimen in patients with type 2 diabetes. METHODS: This post-hoc analysis of insulin-naive patients in the DURABLE study randomised to receive either insulin glargine or insulin lispro mix 25 evaluated the percentages of patients achieving a target HbA1c of <7.0% (<53mmol/mol) per baseline HbA1c quartiles, and the effect of each insulin regimen on the relative contributions of PHG and FHG to overall hyperglycaemia. RESULTS: Patients had comparable demographic characteristics and similar HbA1c and FHG values at baseline in each HbA1c quartile regardless of whether they reached the target HbA1c. The higher the HbA1c quartile, the greater was the decrease in HbA1c, but also the smaller the percentage of patients achieving the target HbA1c. HbA1c and FHG decreased more in patients reaching the target, resulting in significantly lower values at endpoint in all baseline HbA1c quartiles with either insulin treatment. Patients not achieving the target HbA1c had slightly higher insulin doses, but lower total hypoglycaemia rates. CONCLUSION: Smaller decreases in FHG were associated with not reaching the target HbA1c, suggesting a need to increase basal or premixed insulin doses to achieve targeted fasting plasma glucose and improve patient response before introducing more intensive prandial insulin regimens. [less ▲]

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See detailFactors associated with recurrent hamstring injuries
Croisier, Jean-Louis ULg

in Sports Medicine (2004), 34(10), 681-695

A history of muscle injury represents a predominant risk factor for future insult in that muscle group. The high frequency of re-injury and persistent complaints after a hamstring strain comprise major ... [more ▼]

A history of muscle injury represents a predominant risk factor for future insult in that muscle group. The high frequency of re-injury and persistent complaints after a hamstring strain comprise major difficulties for the athlete on return to athletic activities. Some of the risk factors associated with the possible recurrence of the injury are, in all probability, already implicated in the initial injury. One can distinguish between those events peculiar to the sport activity modalities (extrinsic factors) and other contributing factors based on the athletes individual features (intrinsic factors). For both categories, the persistence of mistakes or abnormalities in action represent an irrefutable component contributing to the re-injury cycle. Additional factors leading to chronicity can come from the first injury per se through modifications in the muscle tissue and possible adaptive changes in biomechanics and motor patterns of sporting movements. We emphasise the role of questionable approaches to the diagnosis process, drug treatment or rehabilitation design. To date, the risk factors examined in the literature have either been scientifically associated with injury and/or speculated to be associated with injury. In this context, quantifying the real role of each factor remains hypothetical, the most likely ones corresponding to inadequate warm-up, invalid structure and the content of training, muscle tightness and/or weakness, agonist/antagonist imbalances, underestimation of an extensive injury, use of inappropriate drugs, presence of an extensive scar tissue and, above all, incomplete or aggressive rehabilitation. Such a list highlights the unavoidable necessity of developing valid assessment methods, the use of specific measurement tools and more rigorous guidelines in the treatment and rehabilitation. This also implies a scientific understanding as well as specifically qualified medical doctors, physiotherapists and trainers acting in partnership. [less ▲]

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See detailFactors associated with self-perceived burden to the primary caregiver in older patients with hematologic malignancies: an exploratory study
Libert, Y; Borghgraef, C; BEGUIN, Yves ULg et al

in Psycho-oncology (2017), 26

Objective: Although cancer patients frequently experience self-perceived burden to others, this perception has not been enough studied. The aim of this study was to investigate the prevalence of ... [more ▼]

Objective: Although cancer patients frequently experience self-perceived burden to others, this perception has not been enough studied. The aim of this study was to investigate the prevalence of selfperceived burden to the primary caregiver (SPB-PC) and associated factors in an older patient population with hematologic malignancies at the time of chemotherapy initiation. Methods: In total, 166 consecutive patients with hematologic malignancies aged ≥65 years were recruited at the time of chemotherapy initiation. Patients’ SPB-PC was assessed using a 100-mm visual analogue scale (VAS). Characteristics potentially associated with SPB-PC, including sociodemographic and medical characteristics, physical functioning status (Karnofsky performance score, activities of daily living (ADL)/instrumental ADL), symptoms (fatigue, pain, nausea, quality of life), psychological distress (Hospital Anxiety and Depression Scale (HADS)), perceived cognitive function (Functional Assessment of Cancer Therapy Cognitive (FACT-Cog) Scale), and patients’/primary caregivers’ personal relationship characteristics (family tie, support), were assessed. Results: Thirty-five percent of patients reported moderate to severe SPB-PC (VAS ≥ 50 mm). Patients’ SPB-PC was associated with lower Karnofsky performance (β = 0.135, p = 0.058) and ADL (β = 0.148, p = 0.037) scores, and higher HADS (β = 0.283, p<0.001) and FACT-Cog perceived cognitive impairments subscale (β = 0.211, p = 0.004) scores. The proportion of explained variance was 23.5%. Conclusions: Health care professionals should be aware that about one third of older cancer patients experience moderate to severe SPB-PC at the time of chemotherapy initiation. They should adapt their support of patients who report such a feeling. [less ▲]

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See detailFactors contributing to household-resilience capacity to farming risks: Case study of clam farming in Thai Binh province, Vietnam
Ngo Thi Thu Hang, ULg; Tran, Huu Cuong; Nguyen Thi Khanh Hong, ULg et al

Conference (2016)

Despite coastal endowment is a unique opportunity for coastal farmers it may be embedded with some risks. Vietnam was ranked 18th in world risk index in 2015 with the vulnerability index of 50.87 ... [more ▼]

Despite coastal endowment is a unique opportunity for coastal farmers it may be embedded with some risks. Vietnam was ranked 18th in world risk index in 2015 with the vulnerability index of 50.87% (Garschagen, Hagenlocher et al. 2016). In this context, Vietnamese clam farmers have been experiencing increased difficulties. This research focuses on clam production in Thai Binh province which has the largest clam area in northern and northern central coastal Vietnam. The central question of the research was “which factors contributing to farmer’s resilience to clam farming risks”. Results of the research indicated that there are several factors, which altogether explained 66% of variance of resilience among the households, formed three groups including (1) farmer’s ability in gaining experiences from failures and harnessing new opportunities; (2) farmer’s perception toward clam farming risks and its impacts; (3) farmer’s confidence about financial capacity and incomes from diversifying activities which can be used to invest in clam farming. From these research results, several support strategies have been suggested to enhance this capacity of the clam farmers, in order to minimize the losses while maximizing the benefit when people seek for sustainable livelihood. [less ▲]

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See detailFactors controlling sediment yield at the catchment scale in NW Mediterranean geoecosystems
de Vente, J.; Verduyn, R.; Verstraeten, G. et al

in Journal of Soils and Sediments (2011), 11(4), 690-707

Purpose: This study aimed to (1) increase understanding of the relation between sediment yield and environmental variables at the catchment scale; (2) test and validate existing and newly developed ... [more ▼]

Purpose: This study aimed to (1) increase understanding of the relation between sediment yield and environmental variables at the catchment scale; (2) test and validate existing and newly developed regression equations for prediction of sediment yield; and (3) identify how better predictions may be obtained. Materials and methods: A correlation and regression analysis was performed between sediment yield and over 40 environmental variables for 61 Spanish catchments. Variables were selected based on availability and expected relation with diverse soil erosion and sediment transport processes. For comparison, the Area Relief Temperature (ART) sediment delivery model was applied to the same catchments. Sediment yield estimates obtained from reservoir surveys were used for model calibration and validation. Results and discussion: Catchment area, catchment perimeter, stream length, relief ratio, Modified Fournier Index, the RUSLE's R factor, and catchments percentage with poor vegetation cover showed highest correlations with sediment yield. Stepwise linear regression revealed that variables representing topography, climate, vegetation, lithology, and soil characteristics are required for the best prediction equation. Although calibration results were relatively good, validation showed that the models were unstable and not suitable for extrapolation to other catchments. Reasons for this unstable model performance include (1) lack of detail and quality of the data sources; (2) large variation in catchment characteristics; (3) insufficient representation of all relevant erosion and sediment transport processes; and (4) the presence of nonlinear relations between sediment yield and environmental variables. The nonlinear ART model performed relatively well but systematically overpredicted sediment yield. A model reflecting human impacts, including dams and conservation measures, is expected to provide better results. This, however, requires significantly more input data. Conclusions: Although important insight is obtained into the relation between sediment yield and environmental factors, prediction of sediment yield at the catchment scale requires alternative approaches. More detailed information is required on land cover (change), and the effect of soil conservation measures. Validation of regression equations is a necessity, and better predictions are obtained by nonlinear models. © 2011 Springer-Verlag. [less ▲]

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See detailFactors controlling Si export from soils: A soil column approach
Ronchi, Benedicta; Barao, Lucia; Clymans, Wim et al

in Catena (2015), 133

The release of dissolved silicon (DSi) from A and B horizons was investigated with leaching tests on unsaturated columns. As forest A horizons have larger biogenic Si (BSi) pools than arable lands, we ... [more ▼]

The release of dissolved silicon (DSi) from A and B horizons was investigated with leaching tests on unsaturated columns. As forest A horizons have larger biogenic Si (BSi) pools than arable lands, we compared the Si release from a forest and a cropland from the same geographical region developed on a Luvisol in Belgium and a Cambisol in Sweden. The A horizons released a quickly dissolving Si fraction in contrast to the B horizons, which did contain no or only little amounts of BSi and released lower Si concentrations. Our experiments show that Si export from forest soils is high because of the presence of a large reservoir of soluble BSi as well as due to the acidity of the soil (pH<4). Leaching at two different water fluxes revealed that export in forest soils was transport controlled while cropland soils were in equilibrium. [less ▲]

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See detailFactors controlling soil organic carbon persistence along an eroding hillslope on the loess belt
Wiaux, François; Cornelis, Jean-Thomas ULg; Vanclooster, Marnik et al

in Soil Biology & Biochemistry (2014), 77

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See detailFactors controlling spatial and temporal patterns of multiple pesticide compounds in groundwater (Hesbaye chalk aquifer, Belgium)
Hakoun, Vivien; Orban, Philippe ULg; Dassargues, Alain ULg et al

in Environmental Pollution (2017)

Factors governing spatial and temporal patterns of pesticide compounds (pesticides and metabolites) concentrations in chalk aquifers remain unclear due to complex flow processes and multiple sources. To ... [more ▼]

Factors governing spatial and temporal patterns of pesticide compounds (pesticides and metabolites) concentrations in chalk aquifers remain unclear due to complex flow processes and multiple sources. To uncover which factors govern pesticide compound concentrations in a chalk aquifer, we develop a methodology based on time series analyses, uni- and multivariate statistics accounting for concentrations below detection limits. The methodology is applied to long records (1996–2013) of a restricted compound (bentazone), three banned compounds (atrazine, diuron and simazine) and two metabolites (deethylatrazine (DEA) and 2,6–dichlorobenzamide (BAM)) sampled in the Hesbaye chalk aquifer in Belgium. In the confined area, all compounds had non-detects fractions >80%. By contrast, maximum concentrations exceeded EU’s drinking-water standard (100 ngL-1) in the unconfined area. This contrast confirms that recent recharge and polluted water did not reach the confined area, yet. Multivariate analyses based on variables representative of the hydrogeological setting revealed higher diuron and simazine concentrations in the southeast of the unconfined area, where urban activities dominate land use and where the aquifer lacks protection from a less permeable layer of hardened chalk. At individual sites, positive correlations (up to τ =0,48 for bentazone) between pesticide compound concentrations and multi-annual groundwater level fluctuations confirm occurrences of remobilization. A downward temporal trend of atrazine concentrations likely reflects decreasing use of this compound over the last 28 years. However, the lack of a break in concentrations time series and maximum concentrations of atrazine, simazine, DEA and BAM exceeding EU’s standard post-ban years provide evidence of persistence. Contrasting upward trends in bentazone concentrations show that a time lag is required for restriction measures to be efficient. These results shed light on factors governing pesticide compound concentrations in chalk aquifers. The developed methodology is not restricted to chalk aquifers, it could be transposed to study other pollutants with concentrations below detection limits. Several factors govern pesticide compounds concentrations in the chalk: hydrogeological setting, land use, groundwater level fluctuations and persistence. [less ▲]

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