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See detailFlutter and limit cycle oscillation suppression using linear and nonlinear tuned vibration absorbers
Verstraelen, Edouard ULg; Kerschen, Gaëtan ULg; Dimitriadis, Grigorios ULg

in Proceedings of the SEM IMAC XXXV (2017, February)

Aircraft are more than ever pushed to their limits for performance reasons. Consequently, they become increasingly nonlinear and they are more prone to undergo aeroelastic limit cycle oscillations ... [more ▼]

Aircraft are more than ever pushed to their limits for performance reasons. Consequently, they become increasingly nonlinear and they are more prone to undergo aeroelastic limit cycle oscillations. Structural nonlinearities affect aircraft such as the F-16, which can undergo store-induced limit cycle oscillations (LCOs). Furthermore, transonic buzz can lead to LCOs because of moving shock waves in transonic flight conditions on many aircraft. This study presents a numerical investigation of passive LCO suppression on a typical aeroelastic system with pitch and plunge degrees of freedom and a hardening stiffness nonlinearity. The absorber used is made of a piezoelectric patch glued to the plunge springs and connected to a resistor and an inductance forming a RLC circuit. A mechanical tuned mass damper absorber of similar configuration is also considered. The piezoelectric absorber features significant advantages in terms of size, weight and tuning convenience. The results show that both types of absorber increase the linear flutter speed of the system in a similar fashion but, when optimal, they lead to a sub-critical bifurcation while a super-critical bifurcation was observed without absorber. Finally, it is shown that the addition of a properly tuned nonlinear spring (mechanical absorber) or capacitor (piezo- electric absorber) can restore the super-criticality of the bifurcation. The tuning of the nonlinearity is carried out using numerical continuation. [less ▲]

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See detailCrossoads (Fevrier 2017) - chaque mercredi de 18h à20h - rediffusion: samedis de 22h à min
Sacré, Robert ULg

Diverse speeche and writing (2017)

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See detailEvaluation of the ruminal function of Belgian dairy cows suspected of subacute ruminal acidosis.
Lessire, Françoise ULg; Knapp, Emilie; Theron, Léonard et al

in Vlaams Diergeneeskundig tijdschrift (2017), 86(1), 16-23

Subacute ruminal acidosis (SARA) has been considered a major pathology in high producing dairy herds for years. These findings were corroborated by several studies in Europe. However, different feeding ... [more ▼]

Subacute ruminal acidosis (SARA) has been considered a major pathology in high producing dairy herds for years. These findings were corroborated by several studies in Europe. However, different feeding practices and herds’ production levels are found in Southern Belgium. This study aimed to ascertain whether dairy cows of several herds from the south of Belgium (Wallonia) with a suspicion of SARA really did present too low ruminal pH values. Twenty-four herds were visited and 172 cows were sampled using an oropharyngeal device to collect ruminal fluid, i.e. Geishauser probe. On the samples, three tests were performed: pH measurement, methylene blue reduction test and microscopic evaluation of protozoa vitality. Based on these analyses, no cows demonstrated pH values lower than 5.5 and, only ten cows could be considered at risk for SARA. By contrast, in eightteen cows, pH values higher than 7.0 were measured and ruminal inactivity was suspected. In this study, ruminal alkalosis appeared to be more frequently observed than SARA. [less ▲]

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See detailMapIT!: a simple and user-friendly MATLAB script to
elaborate elemental distribution images from LA-
ICP-MS data

Sforna, Marie-Catherine ULg; Lugli, Federico

in Journal of Analytical Atomic Spectrometry [=JAAS] (2017)

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See detailTransparency Under Scrutiny. Information disclosure by the Parliamentary Land Investigation Commission in Myanmar
San Thein; Pyae Sone; Diepart, Jean-Christophe ULg

E-print/Working paper (2017)

This case study presents a country-wide quantitative analysis of a Parliamentary Commission established in 2012 in Myanmar to examine ‘land grab’ cases considered and to propose solutions towards ... [more ▼]

This case study presents a country-wide quantitative analysis of a Parliamentary Commission established in 2012 in Myanmar to examine ‘land grab’ cases considered and to propose solutions towards releasing the land to its original owners, in most cases smallholder farming families. The study analyses the information contained in four reports released to the public, but also aims to elicit information they do not reveal. First of all, the paper suggests the commission has failed to provide detailed information about land grabs by the military. Second, the Commission seems to have targeted urban areas and urbanization projects and has underestimated land grab cases in rural areas. Third, by contrasting the locations of land confiscation cases with those of agro-industrial concessions as of 2011, the paper also shows how the Commission has evaded, rather than tackled, some very critical land confiscation issues driven by these concessions. Eventually, the authors argue for a mechanism that gathers, manages and releases relevant data on land confiscation and redistribution in a manner that allows for full disclosure. [less ▲]

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See detailMultiscale model of the human cardiovascular system: Description of heart failure and comparison of contractility indices
Kosta, Sarah ULg; Negroni, Jorge; Lascano, Elena et al

in Mathematical Biosciences (2017), 284

A multiscale model of the cardiovascular system is presented. Hemodynamics is described by a lumped parameter model, while heart contraction is described at the cellular scale. An electrophysiological ... [more ▼]

A multiscale model of the cardiovascular system is presented. Hemodynamics is described by a lumped parameter model, while heart contraction is described at the cellular scale. An electrophysiological model and a mechanical model were coupled and adjusted so that the pressure and volume of both ventricles are linked to the force and length of a half-sarcomere. Particular attention was paid to the extreme values of the sarcomere length, which must keep physiological values. This model is able to reproduce healthy behavior, preload variations experiments, and ventricular failure. It also allows to compare the relevance of standard cardiac contractility indices. This study shows that the theoretical gold standard for assessing cardiac contractility, namely the end-systolic elastance, is actually load-dependent and therefore not a reliable index of cardiac contractility. [less ▲]

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See detailImpact of an ultra-marathonof 330km on plasma levels of cardiac biomarkers
Le Goff, Caroline ULg; Kaux, Jean-François ULg; Gergelé, Laurent et al

in British Journal of Sports Medicine (2017, February), 51(4), 347

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See detailA specific immune and lymphatic profile characterizes the pre-metastatic state of the sentinel lymph node in patients with early cervical cancer
Balsat, Cédric ULg; Blacher, Silvia ULg; Herfs, Michael ULg et al

in Oncoimmunology (2017), 6(2), 1265718

The lymph node (LN) pre-metastatic niche is faintly characterized in lymphophilic human neoplasia, although LN metastasis is considered as the strongest prognostic marker of patient survival. Due to its ... [more ▼]

The lymph node (LN) pre-metastatic niche is faintly characterized in lymphophilic human neoplasia, although LN metastasis is considered as the strongest prognostic marker of patient survival. Due to its specific dissemination through a complex bilateral pelvic lymphatic system, early cervical cancer is a relevant candidate for investigating the early nodal metastatic process. In the present study, we analyzed in-depth both the lymphatic vasculature and the immune climate of pre-metastatic sentinel LN (SLN), in 48 cases of FIGO stage IB1 cervical neoplasms. An original digital image analysis methodology was used to objectively determine whole slide densities and spatial distributions of immunostained structures. We observed a marked increase in lymphatic vessel density (LVD) and a specific capsular and subcapsular distribution in pre-metastatic SLN when compared with non-sentinel counterparts. Such features persisted in the presence of nodal metastatic colonization. The inflammatory profile attested by CD8+, Foxp3, CD20 and PD-1expression was also significantly increased in pre-metastatic SLN. Remarkably, the densities of CD20+ B cells and PD-1 expressing germinal centers were positively correlated with LVD. All together, these data strongly support the existence of a pre-metastatic dialog between the primary tumor and the first nodal relay. Both lymphatic and immune responses contribute to the elaboration of a specific pre-metastatic microenvironment in human SLN. Moreover, this work provides evidence that, in the context of early cervical cancer, a pre-metastatic lymphangiogenesis occurs within the SLN (pre-metastatic niche) and is associated with a specific humoral immune response. [less ▲]

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See detailAnalysis and indications on long-term forecasting of the Oceanic Niño Index with wavelet-induced components
Deliège, Adrien ULg; Nicolay, Samuel ULg

in Pure and Applied Geophysics (2017), 174(4), 1815-1826

The present paper provides an analysis and a long-term forecasting scheme of the Oceanic Niño Index (ONI) using the continuous wavelet transform. First, it appears that oscillatory components with main ... [more ▼]

The present paper provides an analysis and a long-term forecasting scheme of the Oceanic Niño Index (ONI) using the continuous wavelet transform. First, it appears that oscillatory components with main periods of about 17, 31, 43, 61 and 140 months govern most of the variability of the signal, which is consistent with previous works. Then, this information enables us to derive a simple algorithm to model and forecast ONI. The model is based on the observation that the modes extracted from the signal are generally phased with positive or negative anomalies of ONI (El Niño and La Niña events). Such a feature is exploited to generate locally stationary curves that mimic this behavior and which can be easily extrapolated to form a basic forecast. The wavelet transform is then used again to smooth out the process and finalize the predictions. The skills of the technique described in this paper are assessed through retroactive forecasts of past El Niño and La Niña events and via classic indicators computed as functions of the lead time. The main asset of the proposed model resides in its long-lead prediction skills. Consequently, this approach should prove helpful as a complement to other models for estimating the long-term trends of ONI. [less ▲]

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See detailLe droit du justiciable dans le cadre de la loi sur l'internement (y compris "pot-pourri III")
Jacques, Elodie ULg

in Masset, Adrien; Franssen, Vanessa (Eds.) Les droits du justiciable face à la justice pénale (2017)

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See detailIntroduction to the Laws of War - Reader (2016-2017)
Deprez, Christophe ULg

Learning material (2017)

This reader gathers introductory pieces of literature on how international law governs situations of armed conflict.

Detailed reference viewed: 19 (3 ULg)
See detailLa paix de Fexhe
Masson, Christophe ULg

Book published by Ville de Liège (2017)

Catalogue de l'exposition "La Paix de Fexhe" (Grand Curtius, 3 février-30 avril 2017)

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See detailCombattre le travail des enfants? Politiques et acteurs d'une lutte controversée au Burkina Faso
Wouango, Joséphine ULg

Book published by L'Harmattan (2017)

Malgré le renforcement de la législation depuis 1990 et la lutte engagée depuis 2000, le travail des enfants continue d’être une question préoccupante au Burkina Faso. Pourquoi ? Alors que la lutte pour ... [more ▼]

Malgré le renforcement de la législation depuis 1990 et la lutte engagée depuis 2000, le travail des enfants continue d’être une question préoccupante au Burkina Faso. Pourquoi ? Alors que la lutte pour son abolition, dans le pays, n’a jamais connu un tel intérêt, comment comprendre que de nombreux enfants continuent de travailler, souvent dans des conditions qui relèvent des « pires formes » de travail des enfants, selon les critères de l’OIT ? Que pensent et disent les enfants travailleurs sur cette lutte engagée contre leur travail ? Telles sont les questions que l’ouvrage se propose de développer. À partir d’une enquête de terrain de longue durée au Burkina Faso, cet ouvrage offre une analyse des conditions d’émergence, de traduction et d’application des politiques internationales de lutte contre le travail des enfants. En confrontant à un corpus empirique inédit les théories et les interprétations dominantes, l’ouvrage propose une relecture de la sociologie et de l’anthropologie de l’enfance et de l’analyse des politiques publiques. [less ▲]

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See detailPhenotypes to genetically reduce greenhouse gas emissions in dairying
de Haas, Yvette; Pszczola, Marcin; Soyeurt, Hélène ULg et al

in Journal of Dairy Science (2017), 100(2), 855-870

Phenotypes have been reviewed to select for lower-emitting animals in order to decrease the environmental footprint of dairy cattle products. This includes direct selection for breath measurements, as ... [more ▼]

Phenotypes have been reviewed to select for lower-emitting animals in order to decrease the environmental footprint of dairy cattle products. This includes direct selection for breath measurements, as well as indirect selection via indicator traits such as feed intake, milk spectral data, and rumen microbial communities. Many of these traits are expensive or difficult to record, or both, but with genomic selection, inclusion of methane emission as a breeding goal trait is feasible, even with a limited number of registrations. At present, methane emission is not included among breeding goals for dairy cattle worldwide. There is no incentive to include enteric methane in breeding goals, although global warming and the release of greenhouse gases is a much-debated political topic. However, if selection for reduced methane emission became a reality, there would be limited consensus as to which phenotype to select for: methane in liters per day or grams per day, methane in liters per kilogram of energy-corrected milk or dry matter intake, or a residual methane phenotype, where methane production is corrected for milk production and the weight of the cow. We have reviewed the advantages and disadvantages of these traits, and discuss the methods for selection and consequences for these phenotypes. [less ▲]

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See detailIs langdurig ziekteverzuim voorspelbaar en meetbaar ?
Goorts, Kaat; Duchesnes, Christiane ULg; Vandenbroeck, Sofie et al

in Tijdschrift voor Bedrijfs- en Verzekeringsgeneeskunde (2017), 25(2), 59-62

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See detailApplication of design space optimization strategy to the developmentof LC methods for simultaneous analysis of 18 antiretroviral medicinesand 4 major excipients used in various pharmaceutical formulations
Habyalimana, Védaste ULg; Mbinze Kindenge, Jérémie ULg; Yemoa, Loconon ULg et al

in Journal of Pharmaceutical & Biomedical Analysis (2017), 139

tAs one of the world’s most significant public health challenges in low- and middle-income countries,HIV/AIDS deserves to be treated with appropriate medicines, however which are not spared from coun ... [more ▼]

tAs one of the world’s most significant public health challenges in low- and middle-income countries,HIV/AIDS deserves to be treated with appropriate medicines, however which are not spared from coun-terfeiting. For that, we developed screening and specific HPLC methods that can analyze 18 antiretroviralmedicines (ARV) and 4 major excipients. Design of experiments and design space methodology wereinitially applied for 15 ARV and the 4 excipients with prediction thanks to Monte Carlo simulations andfocusing on rapidity and affordability thus using short column and low cost organic solvent (methanol)in gradient mode with 10 mM buffer solutions of ammonium hydrogen carbonate. Two other specificmethods dedicated to ARV in liquid and in solid dosage formulations were also predicted and opti-mized. We checked the ability of one method for the analysis of a fixed-dose combination composedby emtricitabine/tenofovir/efavirenz in tablet formulations. Satisfying validation results were obtainedby applying the total error approach taking into account the accuracy profile as decision tool. Then, thevalidated method was applied to test two samples coded A and B, and claimed to contain the tested ARV.Assay results were satisfying only for sample B. [less ▲]

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See detailDe l'évaluation des Enseignements à la régulation des pratiques des enseignants: quels possibles et quelles conditions ?
Detroz, Pascal ULg; Verpoorten, Dominique ULg

in Education & Formation (2017), e307

Cet article propose une modélisation des divers usages des résultats de l’évaluation des enseignements par les étudiants (EEE). Nous considérons l’usage et les effets sur les enseignements, mais également ... [more ▼]

Cet article propose une modélisation des divers usages des résultats de l’évaluation des enseignements par les étudiants (EEE). Nous considérons l’usage et les effets sur les enseignements, mais également ceux produits sur le développement pédagogique des enseignants. Nous déterminons ensuite certains éléments du dispositif EEE favorisant une utilisation accrue et pertinente. [less ▲]

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See detailPédagogie universitaire et Evaluation de l’enseignement par les étudiants 
Younes, Nathalie; Paivendi, Saeed; Detroz, Pascal ULg

in Education & Formation (2017), e307

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