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See detailAssessment of erythromycin toxicity on activated sludge via batch experiments and microscopic techniques (epifluorescence and CLSM)
Louvet, Jean-Noël ULg; Helouin, Yannick; Attik, Ghania et al

in Process Biochemistry (2010), 45

This study investigates erythromycin toxicity toward activated sludge as a function of exposure time and antibiotic concentration. Batch experiments were conducted and microscopic techniques ranging from ... [more ▼]

This study investigates erythromycin toxicity toward activated sludge as a function of exposure time and antibiotic concentration. Batch experiments were conducted and microscopic techniques ranging from bright-field microscopy to epifluorescence and confocal laser scanning microscopy (CLSM), combined with a fluorescent viability indicator (BacLight ® Bacterial Viability Kit, Molecular Probes), allowed us to study erythromycin time-kill activity. The erythromycin toxicity was observed at lower concentration when exposure time increased. A 4 .g/L erythromycin concentration was toxic to heterotrophic bacteria on a 5-day time exposure, and a 5 mg/L concentration inhibited nitrification. These findings are in agreement with the microscopic studies, which showed a latency time before the lower antibiotic concentrations began to kill bacteria. Microscope slide wells were used as micro-reactors in which erythromycin concentration ranged from 0.1 to 1 mg/L. After 45 min there were 94% (SD 3.8) of living bacteria in control micro-reactors, 67% (SD 3.1) in micro-reactors that contained 0.1 mg/L erythromycin and 37% (SD 18.6) in micro-reactors that contained 1 mg/L erythromycin. CLSM allowed visualization of isolated stained cells in the three-dimensional structure of damaged flocs [less ▲]

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See detailAssessment of Eurocode 5 charring rate calculation methods
Cachim, Paulo; Franssen, Jean-Marc ULg

in Proceedings of the Fifth International Conference Structures in Fire (2008)

The basic hypothesis for the assessment of fire resistance of wood structures is that for temperatures above 300 ºC, wood is no longer able to sustain any load. Consequently, the determination of the ... [more ▼]

The basic hypothesis for the assessment of fire resistance of wood structures is that for temperatures above 300 ºC, wood is no longer able to sustain any load. Consequently, the determination of the location of the 300 ºC isotherm, the charring depth, is decisive for the result of fire resistance calculation methods. Charring rate of wood is dependent of numerous factors, such as wood species (density, permeability or composition), moisture or direction of burning (along or across the grain). Eurocode 5, Part 1-2, presents several methods for the calculation of fire resistance of timber structures that are divided into simplified and advanced. In this paper simplified and advanced methods are compared regarding the calculation of the charring depth. Finite element simulations have been performed, using the proposed wood properties of Eurocode 5 using finite element code SAFIR. The influence of parameters such as wood density, moisture or anisotropy has been investigated. The results obtained with finite element calculations were then compared with Eurocode 5 simplified models. Some inconsistencies between methods have been observed. This paper presents proposals to overcome some of the inconsistencies as well as to extend the applicability of the models. [less ▲]

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See detailAssessment of Eurocode 5 charring rate calculation methods
Cachim, Paulo; Franssen, Jean-Marc ULg

in Fire Technology (2010), 46

The base hypothesis for the assessment of fire resistance of timber structures by simple calculation models is that for temperatures above 300 ºC, timber is no longer able to sustain any load ... [more ▼]

The base hypothesis for the assessment of fire resistance of timber structures by simple calculation models is that for temperatures above 300 ºC, timber is no longer able to sustain any load. Consequently, the determination of the location of the 300 ºC isotherm, the charring depth, is decisive for the result of fire resistance calculation methods. Charring rate of timber is dependent of numerous factors, such as wood species (density, permeability or composition), moisture or direction of burning (along or across the grain). Eurocode 5, Part 1-2, presents several methods for the calculation of fire resistance of timber structures that are divided into simplified and advanced. In this paper simplified and advanced methods are compared regarding the calculation of the charring depth and residual cross section strength. Finite element simulations have been performed, employing the proposed timber properties of Eurocode 5 using finite element code SAFIR. The influence of parameters such as timber density and moisture has been investigated. The results obtained with finite element calculations were then compared with Eurocode 5 simplified models. Some inconsistencies between methods have been observed. This paper presents some proposals to overcome some of the inconsistencies as well as to extend the applicability of the models. [less ▲]

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See detailAssessment of existing formulas for equivalent damping to use in direct displacement-based design
Degée, Hervé ULg; Bento, R.; Massena, B.

in Proceedings of the 14th World Conference on Erthquake Engineering (2008)

It is generally stated that an accurate evaluation of the equivalent viscous damping is a crucial step in the DirectDisplacement-Based Design (DDBD) methodology. A wrong assessment of equivalent viscous ... [more ▼]

It is generally stated that an accurate evaluation of the equivalent viscous damping is a crucial step in the DirectDisplacement-Based Design (DDBD) methodology. A wrong assessment of equivalent viscous dampingcan indeed lead to important errors on the actual ductility demand of the structural elements. The objective of thepresent contribution is to assess and compare different existing formulas for the evaluation of the equivalent damping and to provide information on the impact of choosing one or another formulation on the seismicdesign. It is more precisely focused on the very recent proposals of Dwairi – Kowalsky and Blandon –Priestley. [less ▲]

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See detailAssessment of exposure to persistent organochlorine compounds in epidemiological studies on breast cancer : a literature review and perspectives for the CECILE study
Bachelet, D.; Verner, M.-A.; Guihenneuc-Jouyaux, C. et al

in Acta Clinica Belgica (2010), 65(1), 49-57

Breast cancer is the most frequent neoplastic disease in women representing 50,000 new cases each year in France. The well-established risk factors, as those related to the reproductive history, cannot ... [more ▼]

Breast cancer is the most frequent neoplastic disease in women representing 50,000 new cases each year in France. The well-established risk factors, as those related to the reproductive history, cannot account for all cases of breast cancer. Other environmental or lifestyle factors need to be explored in depth. Persistent organochlorine compounds (OCs) have attracted attention because of their endocrine disrupting properties that make them possible risk factors for breast cancer, but most epidemiological studies did not report an association between OC concentrations in blood or adipose tissue and breast cancer risk. In these studies, OC levels were measured in biological samples obtained at the time of cancer diagnosis or only a few years before. In this paper, we review the studies on dichlorodiphenyltrichloroethane (DDT) and polychlorobiphenyl (PCB) exposures in relation to breast cancer. We discuss the relevance of OC biological measurements as lifelong exposure indicators, and we describe a new method for assessing exposure to OCs in epiderniological studies. Most studies were carried out recently and reported OC concentrations that were substantially lower than those reported during the 1960s and 1970s. We make the assumption that these OC levels were not reliable indicators, as they were not measured during etiologically relevant periods in a woman's lifetime, i.e. during the prenatal period, the puberty or the period before a first full-term pregnancy, which are regarded as key periods of vulnerability of mammary gland cells to carcinogens. This may have resulted in non differential exposure misclassification and hence in the absence of an observed association between OC levels and breast cancer in most epidemiological studies. Physiologically-based pharmacokinetic (PBPK) models allow estimating persistent organic pollutant lifetime toxicokinetics profiles retrospec- tively in women, by taking into account individual differences in metabolism and key events that affect OC kinetics such as lactation and weight variations. PBPK models will be applied to the participants of a large French population-based case-control study including 1080 cases and 1055 controls. Exposure misclassification could have prevented from observing an association between exposure to OCs and breast cancer risk. PBPK models could be used as a novel way of assessing exposure to OCs and to investigate the impact of internal exposure at different time windows on breast cancer incidence. [less ▲]

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See detailASSESSMENT OF FATIGUE RELIABILITY FOR JACKET-TYPE OFFSHORE PLATFORMS CONSIDERING DYNAMIC BEHAVOIR
Reza Khedmati, Mohammad; Rigo, Philippe ULg; Amrane, Amirouche ULg et al

in Proceedings of the ASME 2013 32nd International Conference on Ocean, Offshore and Arctic Engineering OMAE 2013 (2013, June)

In order to traditionally investigate the strength of marine structures, the structure is subjected to a maximum static load. However, the marine structures are usually suffering environmental forces ... [more ▼]

In order to traditionally investigate the strength of marine structures, the structure is subjected to a maximum static load. However, the marine structures are usually suffering environmental forces varying with time. Wave forces are the most important time dependent loading that causes fatigue in structural elements and joints. In this paper different methods base on S-N curve and linear elastic failure mechanics are presented. The governing equations and theories that are used in each method are expressed and the application of each method will be discussed. The two main methods of deterministic analyses are: stressbased approach (S-N curve approach) and linear elastic fracture mechanics (LEFM) approaches. These approaches are applicable to different analyzing strategies, ie the first approach is used for cases in which general form of fatigue is dominant, but the latter involves the calculations of reliability as functions of crack geometry and its boundary conditions. The SPD12C jacket platform is also modeled as a case study and the results of fatigue reliability analysis are presented. In this paper a comprehensive method is presented to accurately predict the reliability of offshore platforms. This method is based on S-N curve and the results are compared with the fatigue life of joints. Due to nonlinear interaction of soil and piles and the other affecting parameters such as flexibility of joints, non Gaussian procedure of loading, and nonlinearity of reaction force, the precise analyzing of stress levels will be impossible and a complex numerical analysis could only give limited information about the statistical properties of stress. In order to perform the fatigue analysis and predicting the cycles of stress SACS was used which is known as a powerful software in designing and analyzing offshore structures. In this paper the whole structure was modeled subjected to different forces such as wave and sea currents. The effects of parameters such as marine growth and interaction of soil and piles are also included. The latter is shown to have a significant effect on determination of fatigue life of the platform. [less ▲]

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See detailAssessment of gestation, lactation and fasting on stable isotope ratios in northern elephant seals (Mirounga angustirostris)
Habran, Sarah ULg; Debier, Cathy; Crocker, Dan E. et al

in Marine Mammal Sciences (2010), 26(4), 880-895

Effects of physiological processes such as gestation, lactation and nutritional stress on stable isotope ratios remain poorly understood. To determine their impact, we investigated these processes in ... [more ▼]

Effects of physiological processes such as gestation, lactation and nutritional stress on stable isotope ratios remain poorly understood. To determine their impact, we investigated these processes in simultaneously fasting and lactating northern elephant seals (Mirounga angustirostris). Stable carbon and nitrogen isotope values were measured in blood and milk of 10 mother-pup pairs on days 5 and 22 of lactation. As long- and short-term integrators of diet, blood cells and serum may reflect foraging data or energy reserves from late gestation and lactation, respectively. Limited changes in isotopic signatures of maternal blood over the lactating period were highlighted. Nitrogen isotope fractionation associated with mother-to-offspring transfer of nutrients was generated between mother and offspring during gestation and lactation. This fractionation was tissue and time-specific, it varied between early and late lactation from +0.6‰ to +1.3‰ in blood cells and from +1.1‰ to nonsignificant value in serum. Therefore, if pups appear to be good proxies to investigate the female trophic ecology especially for C sources, much more caution is required in using δ15N values. Further studies are also needed to better define the relative impact of fasting and lactation on the enrichment or depletion of isotopes in different tissues. [less ▲]

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See detailAssessment of glucose metabolism in humans with the simultaneous use of indirect calorimetry and tracer techniques.
Tappy, L.; Paquot, Nicolas ULg; Tounian, P. et al

in Clinical Physiology (1995), 15(1), 1-12

Concomitant measurements of sytemic glucose delivery and carbohydrate oxidation are frequently performed in human investigations. Systemic glucose delivery (SGD) is usually determined using dilution of ... [more ▼]

Concomitant measurements of sytemic glucose delivery and carbohydrate oxidation are frequently performed in human investigations. Systemic glucose delivery (SGD) is usually determined using dilution of infused glucose tracers; net carbohydrate oxidation rate (net CHOOX) can be calculated from respiratory gas exchanges and urinary nitrogen excretion (indirect calorimetry); alternatively, glucose oxidation can be measured from labelled CO2 production during infusion of carbon-labelled glucose tracers. In this paper, the theory underlying the use of each of these techniques is briefly reviewed and qualitative differences are outlined. SGD represents the sum of hepatic glucogenolysis, gluconeogenesis from amino acids or glycerol, and, according to the glucose tracer used, glucose cycles (glucose-phosphate cycle, fructose-phosphate cycle, Cori and glucose-alanine cycles); systemic delivery of exogenous glucose after oral or i.v. glucose administration is also measured. Net CHOOX represents oxidation of glucose arising from hepatic or muscle glycogen or from exogenous glucose; it does not take into account oxidation of glucose formed from amino acids or glycerol, which is included in net protein or lipid oxidation. In contrast, isotopic determination of glucose oxidation corresponds to oxidation of glucose originating from hepatic glycogen breakdown, of exogenously administered glucose, and of glucose formed from amino acids and glycerol. Non-oxidative glucose disposal, calculated as SGD-net CHOOX, corresponds to the sum of gluconeogenesis from amino acids or glycerol (which are included in net protein and lipid oxidation), glucose cycles, and glycogen synthesis. [less ▲]

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See detailAssessment of grazing rates in Daphnia galeata
Thys, Isabelle; Pandolfini, Eliana; Darchambeau, François ULg et al

Conference (1999, September 14)

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See detailAssessment of hallucinations
Bell, Vaughan; Raballo, Andrea; Laroi, Frank ULg

in Laroi, Frank; Aleman, André (Eds.) Hallucinations: A guide to treatment and management (2010)

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See detailAssessment of health claims in the field of bone: a view of the Group for the Respect of Ethics and Excellence in Science (GREES)
Bruyère, Olivier ULg; Rizzoli, René; Coxam, V. et al

in Osteoporosis International (2012), 23

Health claims for food products in Europe are permitted if the nutrient has been shown to have a beneficial nutritional or physiological effect. This paper defines health claims related to bone health and ... [more ▼]

Health claims for food products in Europe are permitted if the nutrient has been shown to have a beneficial nutritional or physiological effect. This paper defines health claims related to bone health and provides guidelines for the design and the methodology of clinical studies to support claims. [less ▲]

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See detailAssessment of high sensitive troponin T and I immunoassays in patients with acute chest
Le Goff, Caroline ULg; Garweg, Christophe ULg; Laurent, Terry et al

in Clinical Chemistry (2010, July), 56(S6), 127

Introduction: Cardiac troponin I and T are specific markers of myocardial injury that are widely used for the diagnosis of acute coronary syndrome (ACS). In acute chest pain without ST-segment elevation ... [more ▼]

Introduction: Cardiac troponin I and T are specific markers of myocardial injury that are widely used for the diagnosis of acute coronary syndrome (ACS). In acute chest pain without ST-segment elevation, they are used to differentiate unstable angina from non ST-segment elevation myocardial infarction (NSTEMI). Recently, troponin assays with higher analytical sensitivities became available to enable the detection of minor myocardial damage and identify individuals at higher risk for ACS. As a result of its high tissue-specificity, cardiac troponin T and I are cardio-specific, highly sensitive markers for myocardial damage. The aim of this study was to evaluate the new higher sensitive troponin (T and I) in patients with stable angina and acute chest pain without ST-segment elevation. Methods: Sixty subjects (mean age : 65.5± 11 years), were included: 20 healthy controls, 20 patients with stable angina, 9 with unstable angina (troponin-) and 18 patients with NSTEMI myocardial infarction (troponin+). The protocol was approved by the ethic committee of the University of Liège (Belgium). High sensitive troponin T (hsTnT) determination was realized on heparin plasma by electrochemiluminescence immunoassay on Modular E (Roche Diagnostic). Troponin I II (TnI II) is a chemiluminescent microparticle immunoassay for the quantitative determination of cardiac troponin-I in heparine plasma on the ARCHITECT i System (Abbott Diagnostic). The lower detection limit of these assays was 0.005μg/L for hsTnT and 0.01μg/L for TnI II. Stastistical analysis was performed using t test. P value <0.05 was considered significant. Results: HsTNT levels were 0.003(0.003, 0.004) [median baseline (1st, 3rd quartile)]ng/ml in controls, 0.0075 (0.00475, 0.014) ng/ml in stable angina, 0.011(0.006, 0.012) ng/ml in unstable angina and 0.3715 (0.1795, 1.00725) ng/ml in NSTEMI ACS. TnI II levels were 0 (0, 0.001) ng/ml in controls and in patients with stable angina, 0.07 (0.005, 0.014) ng/ml in unstable angina and 1.4475 (0.0407, 2.656) ng/ml in NSTEMI. HsTNT and TnI II levels were significantly increased in NSTEMI as compared to control subjects, patients with stable and unstable angina. TnI II levels were also increased in unstable angina as compared to controls. Conclusion: In our population, TnI II was more sensitive than hsTNT to detect minor myocardial damage in patients with unstable angina as compared to controls. Therefore, future studies will have to determine whether TnI II might contribute to better risk stratification and treatment strategy in this group of patients. [less ▲]

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See detailAssessment of insulin resistance in vivo: application to the study of type 2 diabetes.
Scheen, André ULg; Lefebvre, Pierre ULg

in Hormone Research (1992), 38(1-2), 19-27

Besides insulin secretion, insulin sensitivity plays a key role in the feedback glucose-insulin closed loop. It can be altered in numerous physiological, pathological and pharmacological conditions. It ... [more ▼]

Besides insulin secretion, insulin sensitivity plays a key role in the feedback glucose-insulin closed loop. It can be altered in numerous physiological, pathological and pharmacological conditions. It can be estimated in vivo using methods that open the feedback loop (insulin suppression test, glucose clamp) or that analyze the closed loop by employing mathematical models of glucose kinetics. The most popular method is the euglycemic hyperinsulinemic glucose clamp. This test should be ideally coupled with a priming-constant infusion of a glucose tracer together with indirect calorimetry. This combination allows to study the glucose kinetics (Ra and Rd, and thus endogenous-mainly hepatic-glucose production) and its metabolism (oxidation or storage as glycogen), respectively. One alternative approach is the frequently sampled intravenous glucose tolerance test where the dynamic changes in plasma insulin and glucose levels are analyzed using the so-called 'minimal model' method. Noninsulin-dependent or type 2 diabetes is characterized by a significant defect in both insulin secretion and action. The insulin resistance is located at the liver site (increased glucose production) and at the peripheral tissues (decreased oxidation and, even more, defective storage of glucose in the muscles). This insulin resistance, which predominates at the postreceptor level, seems to be genetically determined but is worsened by weight excess and by hyperglycemia itself. This contributes to a vicious circle which aggravates progressively the severity of the disease. [less ▲]

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See detailAssessment of joint space narrowing in knee osteoarthritis has good long-term intercentre reproducibility when read in pairs with a semi-automated device
Gensburger, Deborah; DEROISY, Rita ULg; Arlot, Monique et al

in Osteoporosis International (2012, March), 23(Suppl. 2), 247-248

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See detailAssessment of joint space narrowing with conventional standing antero-posterior radiographs: relief in mild-to-moderate pain is not a confounder in recent osteoarthritis structure-modifying drug trials
Rovati, L. C.; Pavelka, K.; Giacovelli, G. et al

in Osteoarthritis and Cartilage (2006), 14(Suppl. A), 14-18

Objective: Knee pain relief has been suggested to potentially alter radioanatomic positioning in conventional standing antero-posterior knee radiographs. This study was performed to determine whether this ... [more ▼]

Objective: Knee pain relief has been suggested to potentially alter radioanatomic positioning in conventional standing antero-posterior knee radiographs. This study was performed to determine whether this is always the case and in particular if it applied to two recent randomised, placebo-controlled trials showing both symptom- and structure-modification with glucosamine sulfate in knee osteoarthritis. Design: Patients in the two studies were selected if they completed the 3-year evaluations and, irrespectively of treatment, (1) were pain-improvers in that they underwent Western Ontario and McMaster Universities (WOMAC) osteoarthritis index (WOMAC) pain decrease at least equal to the mean improvement observed with glucosamine sulfate, or (2) if their baseline standing knee pain (item #5 of the WOMAC pain scale) was "severe" or "extreme" and improved by any degree at the end of the trials. Changes in minimum joint space width were then compared between treatments. Results: Knee pain was of mild-to-moderate severity in the two original studies and in all patient subsets identified here. Obviously, there were more pain-improvers in the glucosamine sulfate than in the placebo subsets (N 76 vs 57 in pooling the two studies), but WOMAC pain scores improved to the same extent (over 50% relative to baseline). Notwithstanding such a major pain relief, patients in the placebo subsets of both studies suffered a definite mean (SE) joint space narrowing, that was of -0.22 (0.15) mm in the pooled analysis, and that was not observed with glucosamine sulfate: +0.15 (0.07) mm; P= 0.003. Similar evidence was found in the smaller subsets with at least severe baseline standing knee pain improving after 3 years. Conclusions: Knee pain relief did not bias the report of a structure-modifying effect of glucosamine sulfate in two recent long-term trials, possibly due to the mild-to-moderate patient characteristics. Consensus deliverables should acknowledge that the potential limitations of conventional standing antero-posterior radiographs should not be overestimated since they may not apply to all patient populations and to all studies using this gold standard technique. (C) 2006 OsteoArthritis Research Society International. Published by Elsevier Ltd. All rights reserved. [less ▲]

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See detailThe assessment of kidney function
cohen, Eric P.; Krzesinski, Jean-Marie ULg

in Cohen, Eric P (Ed.) Cancer and the Kidney - The frontier of nephrology and oncology (2010)

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See detailAssessment of kidney function: estimating GFR in children.
DELANAYE, Pierre ULg; Ebert, Natalie

in Nature Reviews Nephrology (2012), 8(9), 503-504

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See detailAssessment of Lake Sediment Sensitivity along the North Anatolian Fault
Boes, Xavier; Ulas, Avsar; King, J et al

Conference (2007, October)

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