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See detailLouise de Savoie. The King's Mother
Fagnart, Laure ULiege; Winn, Mary Beth

in Broomhall, Susan (Ed.) Women and Power at the French Renaissance Court (in press)

Louise de Savoie occupies a singular place at the French royal court : neither queen nor queen-mother, but mother of the King, she nonetheless played a prominent role in the political and cultural affairs ... [more ▼]

Louise de Savoie occupies a singular place at the French royal court : neither queen nor queen-mother, but mother of the King, she nonetheless played a prominent role in the political and cultural affairs of France. Daughter of Philippe de Bresse, duc de Savoie, she was raised at the court of her aunt, Anne de France, and married in 1488 at age 11 to Charles d’Angoulême, head of a cadet branch of the royal house of Valois. At Cognac where the couple resided, she gave birth to her illustrious children, Marguerite in 1492, and François in 1494. After the sudden death of her husband in 1496, she was herself still too young to be appointed their official guardian. Obliged to share that responsibility with Louis d’Orléans who became king in 1498, the young widow nonetheless asserted her authority in their education. How she succeeded in establishing her place at court, while her son, at first a distant heir to the throne, rose to be king in 1515, can be viewed through her astute patronage of arts and letters. Keenly aware of the power of books and images, Louise multiplied commissions that would reinforce her own position and that of her family and entourage, striving to align herself with illustrious women, past and present. Identified with “Dame Prudence” as she overcame obstacles and rivals, Louise de Savoie’s tenacious devotion to her children culminated in power that was fully recognized in the appointment of « Madame » as Regent of France. [less ▲]

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See detailAn Optimal Control Formulation of Pulse-Based Control Using Koopman Operator
Sootla, Aivar; Mauroy, Alexandre; Ernst, Damien ULiege

in Automatica (in press)

In many applications, and in systems/synthetic biology in particular, it is desirable to compute control policies that force the trajectory of a bistable system from one equilibrium (the initial point) to ... [more ▼]

In many applications, and in systems/synthetic biology in particular, it is desirable to compute control policies that force the trajectory of a bistable system from one equilibrium (the initial point) to another equilibrium (the target point), or in other words to solve the switching problem. It was recently shown that, for monotone bistable systems, this problem admits easyto-implement open-loop solutions in terms of temporal pulses (i.e., step functions of fixed length and fixed magnitude). In this paper, we develop this idea further and formulate a problem of convergence to an equilibrium from an arbitrary initial point. We show that this problem can be solved using a static optimization problem in the case of monotone systems. Changing the initial point to an arbitrary state allows to build closed-loop, event-based or open-loop policies for the switching/convergence problems. In our derivations we exploit the Koopman operator, which offers a linear infinite-dimensional representation of an autonomous nonlinear system. One of the main advantages of using the Koopman operator is the powerful computational tools developed for this framework. Besides the presence of numerical solutions, the switching/convergence problem can also serve as a building block for solving more complicated control problems and can potentially be applied to non-monotone systems. We illustrate this argument on the problem of synchronizing cardiac cells by defibrillation. Potentially, our approach can be extended to problems with different parametrizations of control signals since the only fundamental limitation is the finite time application of the control signal. [less ▲]

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See detailExploring the effect of a second closely-timed PRP infiltration for tendinopathy
Kaux, Jean-François ULiege; Croisier, Jean-Louis ULiege; Forthomme, Bénédicte ULiege et al

in British Journal of Sports Medicine (in press)

Introduction: Some clinical series have previously evaluated the effect of PRP in the treatment of proximal patellar tendinopathies. Although it is possible that a single infiltrative administration may ... [more ▼]

Introduction: Some clinical series have previously evaluated the effect of PRP in the treatment of proximal patellar tendinopathies. Although it is possible that a single infiltrative administration may prove to be an effective treatment for this indication, most of the existing studies evaluated the effects of successive infiltrations which is arguably likely to increase the risks of complications. Methods: Our study is a single blinded, randomized controlled clinical trial on 20 leisure sportsmen (2 groups, respectively 1 or 2 infiltrations of pure PRP) with chronic proximal patellar tendinopathies, rebel to classical management. PRP was obtained using an aphaeresis machine. The one-year follow-up evaluation consisted of VAS, IKDC and VISA-P scores, while algometer, isokinetic and ultrasounds evaluations were carried out up to 3 months. Results: The concentration of the PRP used was similar in both groups. The VAS significantly decreased with time over the 3-month follow-up period (p=0.002), with no difference observed between the two groups (p=0.2). Values obtained with the pressure algometer increased with time across both groups over the 3-month follow-up period (p<0.0001), and values were significantly higher for Group 1 (p=0.001). The IKDC score increased with time in both groups over the follow-up period (p=0.034), with values again significantly higher for Group 1 (p=0.0026). The VISA-P score increased with time in both groups over the follow-up period (p=0.0023), with no difference observed between the groups (p=0.41). No improvements in isokinetic physical performance were observed in either group. However, pain during E30 significantly decreased over the 3-month follow-up period (p=0.027) for patients in both groups. No improvement in either jumping performances or in pain was observed in either group during opto-jump evaluation. No improvements in US findings were observed. After one year, 90% patients of group 1 did not report anymore pain during daily activities, in comparison with only 20% in group 2. Conclusions: A second closely-timed infiltration of PRP to treat proximal patellar tendinopathies is not necessary to improve the efficacy of this treatment. [less ▲]

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See detailCross-cultural adaptation in French and validation of Functional Assessment Scale for acute Hamstring injuries
Kaux, Jean-François ULiege; Willems, Tom; Locquet, Médéa ULiege

in British Journal of Sports Medicine (in press)

Introduction : Acute hamstring injury is a very common muscle injury particularly in sports that require high explosive strength, sports with impulsions and sports with running phases. Among those sports ... [more ▼]

Introduction : Acute hamstring injury is a very common muscle injury particularly in sports that require high explosive strength, sports with impulsions and sports with running phases. Among those sports, the most widespread are soccer, rugby and sprinting. The Functional Assessment Scale for acute Hamstring injuries (FASH) assesses pain, physical activity and how patients realize some exercises while suffering hamstring injury. Current available versons are in English, in German and in Greek. Objectives : The aims of thus study were to reach a reliable and valid translation and a cross-cultural adaptation of this questionnaire in French. Methods: FASH translation and adaptation were realized in respect of international guidelines. The population composed of 116 subjects filled the questionnaire twice separated by 48-60th. FASH reliability and validity were assessed thanks to SF-36 allowing us to assess the test re-test reliability (with intra-class correlation ICC), internal consistency (with Cronbach’s alpha coefficient and construct validity, with Spearman’s correlation coefficients). Results : ICC showed a strong correlation between test and re-test (ICC total=0.9985). Internal consistency was also found to be strong with Cronbach’s alpha coefficient = 0.98. Correlation between FASH and SF-36 overall score was considered as strong (Rs=0.69, p<0.0001). Correlation with SF-36 sub scales (PF, RP, BP) were also considered as strong, showing their convergent validity. Other SF-36 subclass (GH, MH, REm, SF, VT) displayed a moderate correlation with FASH questionnaire, showing their divergent validity. No floor or ceiling effect was observed. Conclusions: FASH translation and cross-cultural adaptation into French can be considered as successful. FASF-F is now a reliable and valid tool for patients suffering acute hamstring injury. [less ▲]

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See detailComparison of Platelet Rich Plasma (PRP) versus Hyaluronic Acid (HA) injections to treat patellar tendinopathies
Kaux, Jean-François ULiege; Roberjot, Mathieu; SAMSON, Antoine ULiege

in British Journal of Sports Medicine (in press)

Introduction: The treatment of patellar tendinopathies could be difficult. Recent systematic review concluded that PRP could be recommend as a treatment in such indication. Recently, the viscoelastic ... [more ▼]

Introduction: The treatment of patellar tendinopathies could be difficult. Recent systematic review concluded that PRP could be recommend as a treatment in such indication. Recently, the viscoelastic properties of hyaluronic acid (HA) on liquid connective tissue have been proposed for the treatment of tendinopathies. Some observations also support its use in a clinical setting to improve pain and function. We aimed to compare the effect of PRP injection versus two injections of HA after three months on patients who have a proximal patellar tendinopathy. Methods: Thirty-three sportsmen with proximal patellar tendinopathies being not relieved after minimum three months of normal physiotherapy treatments where included. Eighteen of them (group 1) have received a leukocyte poor PRP injection (obtained using an aphaeresis machine (3)) and the other fifteen (group 2) two HA injections, all of them have benefited of standardized rehabilitation. Concerning the evaluation of the pathology, algo-functional tests (visual analogic scale (VAS), pressure algometer, IKDC score, VISA-P score), isokinetic (associated to VAS) along with the patellar tendon ultrasonography (US) have been realized over three times (pre-injection, after 6 weeks, after 3 months post-injections). Results: The results of VAS (p<0,01), algometric scores (p<0,01), IKDC scores (p<0,01) and VISA-P (p<0,01) show a considerable improvement in the two groups, but not for the US findings. For the group 1, isokinetic tests show significative results for the hamstrings in C60°/s with an improvement of maximum peak torque (p=0,01) for the pathological member, a diminution (p>0,05) for the healthy limb and during the analysis of the bilateral difference (p=0,0002). For the group 2, the improvement of quadriceps maximum peak torque in C240°/s is significant (p>0,01) for the pathological knee after 6 weeks post-injections only. The VAS associated with isokinetic tests decreases significantly for all contraction modes after three months of study. Conclusion: Both PRP and HA can improve the symptoms of proximal patellar tendinopathy, even if the results are slightly better in the PRP group. [less ▲]

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See detailFrench Translation and validation of the Exercise-Induced Leg Pain
Kaux, Jean-François ULiege; Hagelstein, Thibaut; Van Beveren, Julien et al

in British Journal of Sports Medicine (in press)

Objective: The « Exercise-Induced Leg Pain » (EILP) questionnaire has been developed (in German) to evaluate the severity of symptoms and sports ability in individuals with exercise-induced leg pain. The ... [more ▼]

Objective: The « Exercise-Induced Leg Pain » (EILP) questionnaire has been developed (in German) to evaluate the severity of symptoms and sports ability in individuals with exercise-induced leg pain. The purpose of the present study was to translate and cross-culturally adapt this questionnaire into French and to study the reliability and validity of the French-translated version (EILP-F). Methods: Translation and cross-culturally adaptation of the original EILP (EILP-G) was performed according to established guidelines. The translation part was articulated in six stages: (i) two initial translations from German to French; (ii) synthesis of the two translations; (iii) backward translations; (iv) expert committee to compare the backward translations with the original questionnaire; (v) pre-test; and (vi) approval of the final version of the EILP-F. To validate the EILP-F questionnaire, 84 subjects were recruited (28 pathological patients with a confirmed diagnosis of chronic leg pain, 28 asymptomatic sport students, 28 athletes healthy control). Discriminative power of the questionnaire was tested as well as reliability (internal consistency, test–retest reliability after a 7-10-day interval), construct validity and floor/ceiling effects. Results: the EILP-F version of the questionnaire has been generated without any major difficulties. The ability of the questionnaire to discriminate the three groups of subjects has been showed with a total score of 61.0 ± 18.5 for the pathologic group; 93.9 ± 7.57 for the asymptomatic group and 94.1 ± 9.79 for the control group (p-value adjusted on age = 0.008). A high internal consistency (Cronbach's alpha of 0.93) and an excellent test-retest radiality (ICC of 0.98 (95% CI 0.97-0.99, p<0.001)) indicated that the EILP-F is reliable. The EILP-F also demonstrated a good construct validity against different subscales of the Short Form-36 questionnaire, a generic quality of life questionnaire, with more than 87 % of prespecified hypotheses confirmed. Finally, no floor or ceiling effects were observed. Conclusion: The EILP-F questionnaire, a French version adapted from the original EILP-G, was successfully translated and cross-culturally adapted. The EILP-F questionnaire is consistent, valid and reliable for evaluating the French-speaking patients with chronic exercise-induced leg pain. [less ▲]

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See detailFrench translation and validation of the AKPS questionnaire
Buckinx, Fanny ULiege; Remy, Gaël; Bornheim, Stephen ULiege et al

in British Journal of Sports Medicine (in press)

Introduction: The Anterior Knee Pain Scale (AKPS) is a questionnaire used to examine the subjective symptoms, such as the functional limitations and the anterior knee pain. First developed in English ... [more ▼]

Introduction: The Anterior Knee Pain Scale (AKPS) is a questionnaire used to examine the subjective symptoms, such as the functional limitations and the anterior knee pain. First developed in English, this questionnaire has since been translated and validated into several languages. The aims of the study were to translate and cross-culturally adapt the AKPS into French and to evaluate the reliability and validity of this translated version of the questionnaire. Methods: The translation part was articulated in six stages, according to international guidelines: (i) two initial translations from english to french; (ii) synthesis of the two translations; (iii) backward translations into the original language; (iv) expert committee to compare the backward translations with the original questionnaire (v) pre-final version testing and (VI) expert committee appraisal. To validate the French AKPS questionnaire, we assessed its validity, reliability and floor/ceiling effects. To do this, volunteer patients from Belgium and France, with patellofemoral pain syndrome were asked to answer the french version of the AKPS questionnaire at baseline and after 7 days, as well as the generic SF-36 questionnaire. Results: The AKPS questionnaire was translated without any major difficulties. A total of 101 subjects aged 34.49 ± 11.38 years on average were included in this study. Among them, 58.4% were women. Results indicated an excellent test-retest reliability (intraclass coefficient correlation of 0.97, 95% CI 0.96 - 0.98), a high internal consistency (Cronbach’s alpha of 0.87), a consistent construct validity (high correlations with the SF-36 questionnaire were found with domains related to physical function (r = 0.80), physical role (r = 0.70), pain (r = 0.64)) and low or moderate correlations with domains related to mental health (r = 0.26), vitality (r = 0.32), social function (r = 0.41)). Moreover, no floor/ceiling has been found. Conclusion: A valid AKPS french questionnaire is now available and can be used with confidence to better assess the disease burden associated with femoropatellar syndrom. It was successfully cross-culturally adapted into French. [less ▲]

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See detailIsokinetic profile of subjects with proximal patellar tendinopathy
Kaux, Jean-François ULiege; Croisier, Jean-Louis ULiege; Libertiaux, Vincent ULiege

in British Journal of Sports Medicine (in press)

Introduction Patellar tendinopathy (PT) is commonly observed in jumping sports. Even if its biomechanic is somewhat explored, no information is known about the muscle strength profile of these patients ... [more ▼]

Introduction Patellar tendinopathy (PT) is commonly observed in jumping sports. Even if its biomechanic is somewhat explored, no information is known about the muscle strength profile of these patients. We aimed to determine if there exists a specific profile of patients suffering from a PT Methods 43 patients (42 males; 29 y.o +/- 9.8 y.o) suffering from PT were recruited. To be eligible, the patients must not have suffered from any other traumatic or micro-traumatic injury than the PT on the pathologic limb. After a physical examination, the tendon damage was assessed by ultrasounds examination. The patients were then tested on an isokinetic dynamometer and the peak torque per unit of mass (PTm) developed by the quadriceps and the hamstrings were recorded for various testing modalities. After each test, a visual analog scale (VAS) was used to estimate the pain felt by the patients. Results No significant correlation was found between the MTm and the demographic variables. The difference in MTm between the healthy and the pathological limbs was significant only in concentric 60°/s, for both the quadriceps and the hamstrings. Lastly, the VAS score showed that the most intense pain was experienced after the eccentric test. Conclusions There is no specific patient strength profile emerging from the isokinetic test. This stresses the importance for the clinicians to make testing and to apply a personalized treatment to each patient. On the other hand, the isokinetic eccentric testing of the quadriceps could be used to induce a mechanical stress on the tendon for a reliable pain assessment. [less ▲]

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See detailHybrid Fire Testing: Discussion on stability and implementation of a new method in a virtual environment
Sauca, Ana ULiege; Gernay, Thomas ULiege; Robert, Fabienne et al

in Journal of Structural Fire Engineering (in press)

Purpose – The purpose of this paper is to propose a method for Hybrid Fire Testing (HFT) which is unconditionally stable, ensures equilibrium and compatibility at the interface and captures the global ... [more ▼]

Purpose – The purpose of this paper is to propose a method for Hybrid Fire Testing (HFT) which is unconditionally stable, ensures equilibrium and compatibility at the interface and captures the global behavior of the analyzed structure. HFT is a technique that allows assessing experimentally the fire performance of a structural element under real boundary conditions that capture the effect of the surrounding structure. Design/methodology/approach – The paper starts with the analysis of the method used in the few previous HFT. Based on the analytical study of a simple one degree-of-freedom elastic system, it is shown that this previous method is fundamentally unstable in certain configurations that cannot be easily predicted in advance. Therefore, a new method is introduced to overcome the stability problem. The method is applied in a virtual hybrid test on a 2D reinforced concrete beam part of a moment resisting frame. Findings – It is shown through analytical developments and applicative examples that the stability of the method used in previous HFT depends on the stiffness ratio between the two substructures. The method is unstable when implemented in force control on a physical substructure that is less stiff than the surrounding structure. Conversely, the method is unstable when implemented in displacement control on a physical substructure stiffer than the remainder. In multi degrees-of-freedom tests where the temperature will affect the stiffness of the elements, it is generally not possible to ensure continuous stability throughout the test using this former method. Therefore, a new method is proposed where the stability is not dependent on the stiffness ratio between the two substructures. Application of the new method in a virtual HFT proved to be stable, to ensure compatibility and equilibrium at the interface and to reproduce accurately the global structural behavior. Originality/value – The paper provides a method to perform Hybrid Fire Tests which overcomes the stability problem lying in the former method. The efficiency of the new method is demonstrated in a virtual HFT with 3 degrees-of-freedom at the interface, the next step being its implementation in a real (laboratory) hybrid test. [less ▲]

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See detailEthylene/vinyl acetate-based macrocycles via organometallic-mediated radical polymerization and CuAAC ‘click’ reaction
Demarteau, Jérémy ULiege; De Winter, Julien; Detrembleur, Christophe ULiege et al

in Polymer Chemistry (in press)

Recent advances in organometallic-mediated radical polymerization led to unique α,ω-difunctional poly(vinyl acetate) (PVAc) and ethylene/vinyl acetate copolymers (EVA). A copper- catalyzed Huisgen dipolar ... [more ▼]

Recent advances in organometallic-mediated radical polymerization led to unique α,ω-difunctional poly(vinyl acetate) (PVAc) and ethylene/vinyl acetate copolymers (EVA). A copper- catalyzed Huisgen dipolar cycloaddition ring-closure reaction was applied to these difunctional precursors paving the way to unprecedented PVAc and/or EVA macrocycles, and to their PVOH- and EVOH-counterparts after hydrolysis. [less ▲]

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See detailStellar parameters for TRAPPIST-1
Van Grootel, Valérie ULiege; Silva Fernandes, Catarina ULiege; Gillon, Michaël ULiege et al

in Astrophysical Journal (in press)

TRAPPIST-1 is an ultracool dwarf star transited by seven Earth-sized planets, for which thorough characterization of atmospheric properties, surface conditions encompassing habitability and internal ... [more ▼]

TRAPPIST-1 is an ultracool dwarf star transited by seven Earth-sized planets, for which thorough characterization of atmospheric properties, surface conditions encompassing habitability and internal compositions is possible with current and next generation telescopes. Accurate modeling of the star is essential to achieve this goal. We aim to obtain updated stellar parameters for TRAPPIST- 1 based on new measurements and evolutionary models, compared to those used in discovery studies. We present a new measurement for the parallax of TRAPPIST-1, 82.4 $\pm$ 0.8 mas, based on 188 epochs of observations with the TRAPPIST and Liverpool Telescopes from 2013 to 2016. This revised parallax yields an updated luminosity of $L_*=(5.22\pm0.19)\times 10^{-4} L_{\odot}$, very close to the previous estimate but almost twice more precise. We next present an updated estimate for TRAPPIST-1 stellar mass, based on two approaches: mass from stellar evolution modeling, and empirical mass derived from dynamical masses of equivalently classified ultracool dwarfs in astrometric binaries. We combine them through a Monte-Carlo approach to derive a semi-empirical estimate for the mass of TRAPPIST-1. We also derive estimate for the radius by combining this mass with stellar density inferred from transits, as well as estimate for the effective temperature from our revised luminosity and radius. Our final results are $M_*=0.089 \pm 0.006 M_{\odot}$, $R_* = 0.121 \pm 0.003 R_{\odot}$, and $T_{\rm eff} =$ 2516 $\pm$ 41 K. Considering the degree to which TRAPPIST-1 system will be scrutinized in coming years, these revised and more precise stellar parameters should be considered when assessing the properties of TRAPPIST-1 planets. [less ▲]

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See detailNew observations and asteroseismic analysis of the subdwarf B pulsator PG 1219+534
Van Grootel, Valérie ULiege; Peters, Marie-Julie; Green, Elizabeth M. et al

in Open Astronomy (in press)

We present a new asteroseismic modeling of the hot B subdwarf (sdB) pulsator PG 1219+534, based on a 3-month campaign with the Mont4K/Kuiper combination at Mt Bigelow (Arizona) and on updated atmospheric ... [more ▼]

We present a new asteroseismic modeling of the hot B subdwarf (sdB) pulsator PG 1219+534, based on a 3-month campaign with the Mont4K/Kuiper combination at Mt Bigelow (Arizona) and on updated atmospheric parameters from high S/N low and medium resolution spectroscopy. On the basis of the nine independent pulsation periods extracted from the photometric light curve, we carried out an astroseismic analysis by applying the forward modeling approach using our latest (third and fourth generation) sdB models. Atmospheric parameters (Teff = 34 258±170 K, log g = 5.838±0.030) were used as independent constraints, as well as partial mode identification based on observed multiplet structures we ascribed to stellar rotation. The optimal model found is remarkably consistent between various analyses with third and fourth generation of sdB models, and also with previously published analysis with second generation sdB models. It corresponds to a sdB with a canonical mass (0.46 ± 0.02 M⊙), rather thin H-He envelope (log q(envl)= −3.75 ± 0.12), and close to He-burning exhaustion (Xcore(C + O) = 0.86 ± 0.05). We also investigate the internal rotation of the star. We find that PG 1219+534 rotates very slowly (Prot=34.91 ± 0.84 days) and that solid-body rotation is reached at least down to ∼60% of the radius. [less ▲]

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See detailNadeau
Lorent, Fanny ULiege

in Coste, Claude (Ed.) Dictionnaire Roland Barthes (in press)

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See detailRécit
Lorent, Fanny ULiege; Chassain, Adrien

in Coste, Claude (Ed.) Dictionnaire Roland Barthes (in press)

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See detailDetermining astrophysical parameters of quasars within the Gaia mission
Delchambre, Ludovic ULiege

Doctoral thesis (2018)

Quasars are one of the most peculiar types of objects in astronomy. The supermassive black hole these harbour effectively makes the surrounding matter radiates an enormous amount of energy before getting ... [more ▼]

Quasars are one of the most peculiar types of objects in astronomy. The supermassive black hole these harbour effectively makes the surrounding matter radiates an enormous amount of energy before getting in the vicinity of the black hole horizon out of which it will never escape. This ironically leads to the most luminous phenomenon in the Universe while being non-transient. It is hence quite natural to rely on these cosmic headlights, visible up to ages when the Universe was still very young, so as to achieve some of the currently most important cosmological applications, notably regarding the determination of the cosmological parameters $H_0$, $\Omega_\Lambda$ and $\Omega_m$. The Gaia mission, on its side, is one of a kind given the one billion of celestial objects it is intended to observe, among which more than half a million quasars are expected. Furthermore, owing to its exceptional astrometric precision, Gaia stands out to be extremely well suited for the detection of gravitational lens (GL) systems. In the latter, light rays coming from a distant background quasar are deflected by the presence of a massive galaxy being in the line-of-sight that leads to the production of multiple images of this background quasar upon a favourable alignment between the quasar, the galaxy and the observer. Supplemental constraints on the aforementioned cosmological parameters being then gained based on these GLs. Gaia hence provides an unprecedented opportunity to detect and characterize quasars as well as to identify GLs which ultimately bring a better understanding of the Universe we live in. This thesis is accordingly concerned with the development of software solutions dedicated to the determination of the astrophysical parameters (APs) of the quasars that Gaia will observe, on one hand, and to the recognition of the GLs among the billion of sources it will uncover, on the other hand. Although Gaia provides state-of-the-art astrometric and photometric observations, its capability in characterizing these celestial objects remains however restricted by the relatively low spectral resolution of the blue and red spectrophotometers upon which it is based as well as by the limited signal-to-noise ratio that is associated with faint objects, including quasars. In addition, the overwhelming amount of data that Gaia has to process translates into a stringent need for algorithms having both low numerical complexities as well as low memory usages. These restrictions and shortcomings along with the requirement for reliable APs were at the heart of this research that led to the development of two specifically designed methods that are the weighted principal components analysis and the weighted phase correlation method. The former of these methods allowed us to extract the most significant patterns out of quasars with a view of using these in the production of a spectral library of quasars as observed by Gaia. These were subsequently used in a fast and automated procedure designed to guess the redshift of the quasars within the Gaia mission through the latter mentioned method. Other APs that are the slope of the quasar continua, the total equivalent width of their emission lines and whether these encompass broad absorption lines or not, being then concurrently derived based on the results of these methods. Finally, the identification of GL candidates relies on the recognition of the structures and symmetries that are observed within lensed images through supervised learning methods. The specific method we choose to use, based on extremely randomized trees, was shown to yield a low contamination rate on simulated configurations composed of three images as well as a very high probability of detection in cases of four image configurations. Real observations out of the first Gaia data release were processed and resulted in the identification of candidates having three potentially lensed images which are currently waiting for confirmation using ground-based facilities. [less ▲]

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See detailNuovi culti eroici nell'alto Ellenismo: una riconsiderazione di destinatari, attori e contesti
Caneva, Stefano ULiege; Coppola, Alessandra

Conference (2018, November)

This paper explores the entanglement between social status and the bestowal of heroic honours upon deceased political leaders and elite members in the late-classical and early Hellenistic period ... [more ▼]

This paper explores the entanglement between social status and the bestowal of heroic honours upon deceased political leaders and elite members in the late-classical and early Hellenistic period. Epigraphic and literary sources shedding light on the establishment, justification and social impact of heroic honours practised by different social groups will be discussed, to investigate the implications of the social status of cult agents and recipients upon the definition of the position of honoured humans in relation to the superhuman sphere. This will also imply exploring the types of relationships existing between private heroic foundations and royal divine foundations in the studied period. Contrary to a generally accepted assumption, it will be argued that heroization was common for members of elite families, while it was not the primary option to reward local political leaders, since their honours were principally modelled after godlike honours. For instance, when they came into existence during the mid-Hellenistic period, cults for high-ranking civic leaders were largely modelled on godlike honours for monarchs, but were decreed after death – it will be argued – to preserve a hierarchical distinction between the social status of their recipients. The posthumous bestowal explains why honours for great civic benefactors also drew on typically heroic honours, such as public burial inside the city. However, similar contaminations of heroic and divine honours had already been exploited for the worshipped deceased kings of the early Hellenistic period (e.g. Alexander at Alexandria, Demetrius at Demetrias), so that a certain mixture of divine and heroic features could be said to have been directly transferred from royal to non-royal leaders. In neither case, however, did the presence of heroic features imply that cultic honours for Hellenistic political leaders would be commonly labelled as heroic. A revealing case is that of the Hellenistic leader Aratus, whose “fitting honours” decreed at Sicyon (Polyb. 8.12-7-8; Plut., Arat. 53) are labelled as heroic by moderns only because they were decreed posthumously. Similarly, at Megalopolis, the posthumous honours for the commander Philopoimen comprised a public tomb in the agora – a typically heroic honour – but were labelled as “honours equal to the gods”, not as heroic. We must wait for the late-Hellenistic and Imperial period to trace a significant multiplication of honours for political leaders explicitly labelled heroic. [less ▲]

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See detailRotational and continuous grazing does not affect the total net ecosystem exchange of a pasture grazed by cattle but modifies CO2 exchange dynamics
Gourlez de la Motte, Louis ULiege; Mamadou, Ossenatou; Beckers, Yves ULiege et al

in Agriculture, Ecosystems & Environment (2018), 253

Grassland carbon budgets are known to be greatly dependent on management. In particular, grazing is known to directly affect CO2 exchange through consumption by plants, cattle respiration, natural ... [more ▼]

Grassland carbon budgets are known to be greatly dependent on management. In particular, grazing is known to directly affect CO2 exchange through consumption by plants, cattle respiration, natural fertilisation through excreta, and soil compaction. This study investigates the impact of two grazing methods on the net ecosystem exchange (NEE) dynamics and carbon balance, by measuring CO2 fluxes using eddy covariance in two adjacent pastures located in southern Belgium during a complete grazing season. Rotational (RG) grazing consists of an alternation of rest periods and short high stock density grazing periods. Continuous grazing (CG) consists of uninterrupted grazing with variable stocking rates. To our knowledge, this is the first study to assess the impact of these grazing methods on total net ecosystem exchange and CO2 exchange dynamics using eddy covariance. The results showed that NEE dynamics were greatly impacted by the grazing method. Following grazing events on the RG parcel, net CO2 uptake on the RG parcel was reduced compared to the CG parcel. During the following rest periods, this phenomenon progressively shifted towards a higher assimilation for the RG treatment. This behaviour was attributed to sharp biomass changes in the RG treatment and therefore sharp changes in plant photosynthetic capacity. We found that differences in gross primary productivity at high radiation were strongly correlated to differences in standing biomass. In terms of carbon budgets, no significant difference was observed between the two treatments, neither in cumulative NEE, or in terms of estimated biomass production. The results of our study suggest that we should not expect major benefits in terms of CO2 uptake from rotational grazing management when compared to continuous grazing management in intensively managed temperate pastures. [less ▲]

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See detailRiparian characterization from remote sensing in a multiple scale perspectives. A few examples
Piégay, Hervé; Michez, Adrien ULiege; Raepple, Bianca et al

Conference (2018, October 18)

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