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See detailTowards an Observatory for Network Transparency Research
Neuhaus, Stephan; Münter, Roman; Edeline, Korian ULg et al

in Applied Networking Research Workshop (2016, July)

The Internet is full of middleboxes that change packets and flows. In fact, there is probably no IP or TCP header that is not affected by at least one middlebox. Obviously, middleboxes impede path ... [more ▼]

The Internet is full of middleboxes that change packets and flows. In fact, there is probably no IP or TCP header that is not affected by at least one middlebox. Obviously, middleboxes impede path transparency, i.e., the idea that an exchange of messages results in more or less the same packets, no matter what path the packets takes. But no one seems to have a truly global view of what middleboxes do to packets on what Internet paths, which would however be an essential knowledge for new transport protocols to be successfully deployed. We address these concerns in the MAMI project by building an observatory of path transparency measurements. The project hosts an extensive set of path transparency measurements - we believe it to be the first dataset to deal specifically with middlebox involvement. In this paper, we describe that Observatory and a number of questions that we want to address with the data in that Observatory. Eventually, the project will provide public access to that Observatory so that researchers and the interested public can ask their own questions about path transparency issues and middlebox involvement. [less ▲]

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See detailProtecting Assets Under Non-Parametric Market Conditions
Choffray, Jean-Marie ULg; Pahud de Mortanges, Charles ULg

in Longin, François (Ed.) Extreme Events in Finance: A Handbook of Extreme Value Theory and its Applications (2016)

Under non-parametric market conditions, investors usually become more concerned about the return of their money than about the return on their money. Protecting assets becomes the surest if not the only ... [more ▼]

Under non-parametric market conditions, investors usually become more concerned about the return of their money than about the return on their money. Protecting assets becomes the surest if not the only path to survival and growth. High frequency trading systems, over leveraged shadow entities, flash crashes, and stealth central bank actions, to name a few, contribute to create a “Rumsfeldian” type of world in which decision makers have to cope not only with “Known knowns” – things they know that they know – but also with “Unknown unknowns” – things they don’t know that they don’t know! The goal of this chapter is to explore such a conceptual model of the “Unknown” and to derive from it a concise and coherent set of battle-tested heuristics aimed at designing effective investment strategies to protect assets. [less ▲]

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See detailCyclin-dependent protein kinase inhibitors in breast cancer treatment
FRERES, Pierre ULg; LOUSBERG, Laurence ULg; JERUSALEM, Guy ULg

in Belgian Journal of Medical Oncology [=BJMO] (2016), 10(4), 132-138

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See detailDynamics of a thin radial liquid flow
De Cock, Nicolas ULg; Massinon, Mathieu ULg; Ouled Taleb Salah, Sofiene ULg et al

in Fire Safety Journal (2016), 83

The present work proposes an extension of the existing analytical development on the radial spread of a liquid jet over a horizontal surface to the case of a thin radial flow. When the gap, H, between the ... [more ▼]

The present work proposes an extension of the existing analytical development on the radial spread of a liquid jet over a horizontal surface to the case of a thin radial flow. When the gap, H, between the jet nozzle and the plate is reduced the discharging area may be smaller than the inlet area leading to an increase of the main flow velocity downstream of the thin cylindrical opening. This increase of velocity, de fined here as 1/alpha , can be related to the relative gap of the nozzle H/R with R the nozzle pipe radius. Numerical computations with a volume of fluid method were realised with for H/R ranging from 0.2 to 3 and with flow rates Q of 3 and 6 l/min1. The results of these computations allowed to express alpha in respect of H/R. Taking in account the flow acceleration allowed to extend the set of equation from the jet impacting flow to the thin cylindrical opening flow. The liquid layer thickness and the surface velocity diff er with a maximum error of 4% between the flow predicted by the model and computations. Main discrepancies appear in the region close to the nozzle where the analytical model assumption of a constant velocity outside the boundary layer is not valid. However, further downstream the model and the computations are in good agreement. [less ▲]

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See detailBRAIN-TRAINS: Scenario development to explore intermodal rail transport expansion in, from and towards Belgium
Troch, Frank; Vanelslander, Thierry; Sys, Christa et al

Conference (2016, July)

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See detailPoor Performance of a Retrofitted Downstream Bypass Revealed by the Analysis of Approaching Behaviour in Combination with a Trapping System
Ovidio, Michaël ULg; Dierckx, Arnaud ULg; Bunel, Sarah et al

in River Research & Applications (2016), DOI: 10.1002/rra.3062

The implementation of fish downstream migration bypass systems is still a major challenge, and there is interest in validating the adequacy of different configurations of bypass devices. In the Amblève ... [more ▼]

The implementation of fish downstream migration bypass systems is still a major challenge, and there is interest in validating the adequacy of different configurations of bypass devices. In the Amblève River (Belgium), a mobile 3.3-m height dam feeds two principal Francis and one Francis micro-turbine and is equipped with a modern vertical slot fish pass and a downstream bypass. The aim of this study was to test the bypass attraction and efficiency (i.e. percentage of fish that approach the entrance and use the bypass) for Atlantic salmon smolts. During three consecutive years, a total of 1346 smolts were equipped with a radio frequency identification tag and released from March to May upstream of the dam of Lorcé. The entrance of the downstream migration bypass was equipped with a radio frequency identification antenna in order to detect the smolts approaching. In 2014, a capture cage was also placed downstream the bypass to evaluate its efficiency. The mean percentage of detected smolts at the entrance varied from 26.2 to 39.7%. In 2014, 16.5% of the released smolts entered the bypass and were finally caught in the cage, representing 39% of the smolts detected at the entrance. More than 98% of the detections occurred during night (mainly between 9 PM and 3 AM). The searching delay near the bypass entrance varied from less than 5 min to more than 5 days (median 4.3 min). Visual observation indicated a behavioural reluctance before entering the bypass, with a shift from positive to negative rheotaxy. Our results underline the difficulty to install retrofitted bypass system on old existing hydropower plants. Copyright © 2016 John Wiley & Sons, Ltd. [less ▲]

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See detailAnionic flow polymerizations toward functional polyphosphoesters in microreactors: Polymerization and UV-modification
Baeten, Evelien; Vanslambrouck, Stéphanie; Jérôme, Christine ULg et al

in European Polymer Journal (2016), 80

The polymerization of cyclic phosphates to poly(phosphoester)s, PPEs, is optimized for chip- based microreactors under continuous flow conditions. The anionic ring-opening polymerization of 2-isobutyoxy-2 ... [more ▼]

The polymerization of cyclic phosphates to poly(phosphoester)s, PPEs, is optimized for chip- based microreactors under continuous flow conditions. The anionic ring-opening polymerization of 2-isobutyoxy-2-oxo-1,3,2-dioxaphospholane (iBP) via the use of two organocatalytic systems allowed to polymerize to nearly quantitative monomer conversion within 10 or 3 minutes, respectively at a reaction temperature of 40 °C. Further, the optimized polymerization protocol was applied to 2-butenoxy-2-oxo-1,3,2-dioxaphospholane (BP) which yields a polymer that carries an alkene functionality per monomer repeating unit. This material can be postmodified in an UV-induced radical thiol-ene reaction, which was also shown to proceed with very high efficiency under UV-flow conditions. Eventually, both reactions were coupled in a two-stage reactor setup, showing that the thermally-activated polymerization can be coupled with high efficiency to the UV-activated post-polymerization modification reaction. The introduced reactor setup can in the future be used to produce and screen a broad variety of functional PPE materials with various functionalities and physical properties. [less ▲]

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See detailCoherent backscattering in the Fock space of Bose- and Fermi-Hubbard systems
Engl, Thomas; Dujardin, Julien; Tisserond, Emilie et al

Poster (2016, July)

Coherent backscattering generally refers to a significant and robust enhancement of the average backscattering probability of a wave within a disordered medium, which from a semiclassical point of view ... [more ▼]

Coherent backscattering generally refers to a significant and robust enhancement of the average backscattering probability of a wave within a disordered medium, which from a semiclassical point of view arises due to the constructive interference between backscattered trajectories and their time-reversed counterparts. We recently investigated the manifestation of this wave interference phenomenon in the Fock space of a disordered Bose-Hubbard system of finite extent [1], which can potentially be realized using ultracold bosonic atoms within optical lattices. Preparing the atoms in a well-defined Fock state of the lattice and letting the system evolve for a finite time will, for suitable parameters of the system and upon some disorder average over random on-site energies of the lattice, generally give rise to an equidistribution of the occupation probability within the energy shell of the Fock space that corresponds to the initial energy of the system, in accordance with the quantum microcanonical ensemble. We find, however, that the initial state is twice as often encountered as other Fock states with comparable total energy, which is a consequence of coherent backscattering [1]. Most recently, we showed that this phenomenon also arises in spin 1/2 Fermi-Hubbard rings that involve Rashba hopping terms (which combine inter-site hoppings with spin flips and arise from spin-orbit coupling), for which a newly developed semiclassical theory [2] correctly predicts a coherent enhancement of the occupation probabilities of the initial state and its spin-flipped counterpart. Moreover, performing a global spin flip within this Fermi-Hubbard system will give rise to significant spin echo peaks on those two Fock states, which is again a consequence of quantum many-body interference [3]. The semiclassical predictions of these enhancements and peaks are found to be in very good agreement with numerical findings obtained from the exact quantum time evolution within this Fermi-Hubbard system. [1] T. Engl, J. Dujardin, A. Argüelles, P. Schlagheck, K. Richter, and J. D. Urbina, Phys. Rev. Lett. 112, 140403 (2014). [2] T. Engl, P. Plößl, J. D. Urbina, and K. Richter, Theoretical Chemistry Accounts 133, 1563 (2014). [3] T. Engl, J. D. Urbina, and K. Richter, arXiv:1409.5684. [less ▲]

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See detailCapillary electrophoresis method to determine siRNA complexation with cationic liposomes
Furst, Tania ULg; Bettonville, Virginie ULg; Farcas, Elena ULg et al

in Electrophoresis (2016)

Small interfering RNA (siRNA) inducing gene silencing has great potential to treat many human diseases. To ensure effective siRNA delivery, it must be complexed with an appropriate vector, generally ... [more ▼]

Small interfering RNA (siRNA) inducing gene silencing has great potential to treat many human diseases. To ensure effective siRNA delivery, it must be complexed with an appropriate vector, generally nanoparticles. The nanoparticulate complex requires an optimal physiochemical characterization and the complexation efficiency has to be precisely determined. The methods usually used to measure complexation are gel electrophoresis and RiboGreen® fluorescence-based assay. However, those approaches are not automated and present some drawbacks such as the low throughput and the use of carcinogenic reagents. The aim of this work is to develop a new simple and fast method to accurately quantify the complexation efficiency. In this research, capillary electrophoresis (CE) was used to determine the siRNA complexation with cationic liposomes. The short-end injection mode applied enabled siRNA detection in less than 5 min. Moreover, the CE technique offers many advantages compared to the other classical methods. It is automated, does not require sample preparation and expensive reagents. Moreover, no mutagenic risk is associated to CE approach since no carcinogenic product is used. Finally, this methodology can also be extended to the characterization of other types of nanoparticles encapsulating siRNA, such as cationic polymeric nanoparticles. [less ▲]

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See detailInsight into biting diversity to capture benthic prey in damselfishes (Pomacentridae)
Olivier, Damien ULg; Parmentier, Eric ULg; Frederich, Bruno ULg

in Zoologischer Anzeiger (2016), 264

The cerato-mandibular (c-md) ligament, joining the hyoid bar to the coronoid process of the angular, allows Pomacentridae to slam their mouth shut in a few milliseconds. Previous works have revealed that ... [more ▼]

The cerato-mandibular (c-md) ligament, joining the hyoid bar to the coronoid process of the angular, allows Pomacentridae to slam their mouth shut in a few milliseconds. Previous works have revealed that such a mechanism is used to feed, but some variability in biting patterns has been observed between two damselfish species. The pelagic feeder Amphiprion clarkii performs two different kinematic patterns to bite fixed prey, one that does not depend on the c-md ligament (biting-1) and one that does (biting-2). The benthic feeder Stegastes rectifraenum only performs biting-2. The present study aims to shed light on the occurrence of biting-2 in the feeding behaviour of Pomacentridae. To test our hypothesis that biting-2 would be the only biting pattern for benthic feeders, we compared biting behaviours among four species: one pelagic feeder, A. clarkii, and three benthic feeders, Neoglyphidodon nigroris, Stegastes leucostictus and S. rectifraenum. Our results showed that the four species were able to perform biting-2, but they do not support that the use of this pattern is related to trophic habits. Contrary to S. rectifraenum, the two other benthic feeders randomly used biting-1 and biting-2 patterns, similar to A. clarkii. Two hypotheses are discussed for explaining this variability within Pomacentridae. Finally, it has been recently shown that some damselfishes do not possess the c-md ligament. We therefore included two species lacking the c-md ligament (Chromis chromis and Abudefduf troschelii) in our study and we demonstrate our expectation that they are unable to perform biting-2. [less ▲]

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See detailApplications of the multiple timescale spectral analysis in wind engineering
Denoël, Vincent ULg

in Zingoni, Alphose (Ed.) Proceedings of the Sixth International Conference on Structural Engineering, Mechanics and Computation (2016, July)

The random response of civil engineering structures to the buffeting action of wind loads is typically composed of several components, usually referred to as the background component, in the low fre ... [more ▼]

The random response of civil engineering structures to the buffeting action of wind loads is typically composed of several components, usually referred to as the background component, in the low fre- quency zone and the resonant component(s) in the neighborhood of modal natural frequencies. It has become customary to study separately and add the contributions of these components to the total response, at least as far as the second order response (variance of structural responses) is concerned. Such a decomposition exists but is less usual for the computation of covariances of modal coordinates or of structural displacements, which are in turn necessary for the determination of internal stresses. The question of such a decomposition also holds for nonlinear systems, or even for the higher statistical moments of a linear structural system, should the response be non Gaussian. With very wide ranges of applicability, the Multiple Timescale Spectral Analysis summarizes under a unified framework recent works aiming at the development of such decompositions. This paper briefly pictures this particular theory based on perturbation methods, and provides illustrations of its applicability to the problems cited above. [less ▲]

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See detailDistinct cerebral metabolic patterns related to high pain sensitivity in episodic or chronic migraine patients and healthy volunteers
D'Ostilio, Kevin ULg; Lisicki Martinez, Marco ULg; Schoenen, Jean ULg et al

in Frontiers in Aging Neuroscience (2016, July)

Introduction Allodynia, i.e. pain evoked by a non-painful stimulus, is prevalent in chronic pain and in migraine where it augments with disease severity and chronicity [1]. Central sensitization is ... [more ▼]

Introduction Allodynia, i.e. pain evoked by a non-painful stimulus, is prevalent in chronic pain and in migraine where it augments with disease severity and chronicity [1]. Central sensitization is thought to be the culprit [2]. It is not known, however, which central areas are involved. The aim of the present study was to evaluate whether brain metabolism in subjects that are more sensitive to pain is different between migraine patients and healthy controls. Subjects and methods Quantitative heat sensory testing on the forehead and 18FDG-PET were performed in 55 subjects: 20 healthy volunteers (HV, 21-59 years, 5M), 21 patients with episodic migraine in the interictal phase (MO, age range: 20-63 years, 5M) and 14 patients with chronic migraine (CM, age range: 22-62 years, 1M). The 3 cohorts were subdivided according to the median heat pain threshold into subgroups with low and high pain thresholds. PET results were compared between these subgroups in each cohort. Data analyses were restricted to areas of the pain/salience matrix. Results There was no significant difference in heat pain thresholds between HV (median: 43.7 °C), MO median: 44.2°C) and CM (median: 43.3°C) (p=0.64). In an SPM-ANOVA, a contrast modelling the potential gradual effect of increased differences in pain sensitivity in relation to disease severity showed significant metabolic changes in bilateral thalamus and midbrain (p < 0.001). Additional analyses revealed that hypometabolic areas in subgroups with a low heat pain threshold differed between HV (anterior cingulate and somatosensory cortices), MO (lower pons and somatosensory cortex) and CM (midbrain and thalamus) (Figure 1). Conclusion Overall migraine patients do not have reduced heat pain thresholds. However, hypometabolic areas related to high thermal pain sensitivity are strictly cortical in HV, but comprise the pons in episodic migraine and are restricted to midbrain and thalamus in chronic migraine. The distinct central correlates of heat pain sensitivity in migraine patients might therefore represent a biomarker of migraine and its chronification. Legend to figure Figure 1. Hypometabolic areas in low pain threshold subgroups in HV (green), MO (orange) and CM (red). p < 0.01 for display purpose. Résumé en Français: Titre: Métabolisme cérébral distinct en relation avec la sensibilité à la douleur entre sujets sains, migraine épisodique et migraine chronique. Les migraineux ont une sensibilité anormale à la douleur. Les mécanismes cérébraux en sont inconnus. Nous avons comparé le métabolisme cérébral chez des sujets sains et chez des migraineux épisodiques ou chroniques et correlé les résultats avec le seuil douloureux. Les aires cérébrales hypométaboliques liées à un seuil douloureux bas diffèrent entre groupes: régions corticales chez les sujets sains, aires corticales et sous-corticales dans la migraine épisodique, régions sous-corticales dans la migraine chronique .Le contrôle central de la douleur semble modifié distinctement dans les formes de migraine, ce qui pourrait en constituer un biomarqueur et avoir des implications thérapeutiques. [less ▲]

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See detailEntretien avec Michel Dumoulin. Regards sur les mondes de la recherche et de l'histoire.
Genin, Vincent ULg

in Contemporanea (2016), XXXVIII(2),

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See detailDeuxième séminaire vélo
Frankignoulle, Pierre ULg

Diverse speeche and writing (2016)

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See detailBiology of Damselfishes
Frederich, Bruno ULg; Parmentier, Eric ULg

Book published by CRC-Press, Taylor & Francis (2016)

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See detailImpact of a mountain ultra-marathon on cardiac biomarkers
Le Goff, Caroline ULg; Gergelé, Laurent; Kaux, Jean-François ULg et al

in Crossing borders through sport science (2016, July)

Objectives. While moderate exercise has beneficial effects on the cardiovascular system, consequences of a supra-physiological effort are not clear yet. In particular, the physiological consequences of ... [more ▼]

Objectives. While moderate exercise has beneficial effects on the cardiovascular system, consequences of a supra-physiological effort are not clear yet. In particular, the physiological consequences of ultramarathons need to be further documented. The aim of the study was to assess the changes of various cardiac biomarkers after a mountain ultra-marathon. Material and methods. Blood and urine samples were collected on 28 runners (17 men) participating to the Ultra-Trail du Mont Blanc (105km, total positive elevation: 5600 m) at 3 different times: before the race (Pre), within 1 h after the finish (Post) and 7 days after the finish (D+7). Several biomarkers involved in heart disease (coronary syndrome, heart failure and fibrosis) and in inflammation were assayed on different analyzers such a COBAS® (for CKMB,TnThs, NT-proBNP, H-FABP and CRPs) and KRYPTOR® (for Copeptin). ST2 was measured manually with the Presage kit from CRITICAL DIAGNOSTIC®. Results. Plasma levels of cardiac markers (CKMB, TnThs, NT-proBNP, copeptin, H FABP, ST2) and inflammation (CRPs) increased significantly at Post. Means values increased from Pre to Post as follows: 2.3 to 91.9 UI/L for CKMB (p<0.0001); 7.6 to 31.7 ng/L for TnThs (p<0.0001); 41.7 to 1190.5 ng/L for NT-proBNP, 4.2 to 22.9 pmol/L for copeptin (p=0.001); 3.6 to 107.8 ng/mL for H-FABP (p<0.0001), 29.7 to 126.2 ng/mL for ST2 (p<0.0001); 0.5 to 29.1 mg/L for CRPs (p<0.0001). With the exception of a few (H-FABP, ST2, CRPs) biomarkers in some subjects, all values were back to Pre values at D+7. Discussion-conclusion. Prolonged strenuous running exercise caused an elevation in cardiac biomarkers. Elevation in CK-MB levels lacks specificity for cardiac damage as runners have increased CKMB from skeletal muscles as well. Previous studies suggested that exercise induced TnThs elevation is a benign reversible physiologic phenomenon but this parameter, as well as H-FABP, could be a sign of ischemia. Different phenomena occurred such as stretch of myocytes causing an increase in pressure or volume and neurohormonal activation which can explain the Copeptine and NT-proBNP increase, while ST2 is a biomarker of cardiac remodeling and fibrosis. CRP is an acute phase compound that tends to increase following a strenuous and prolonged bout of exercise and/or muscular injury. As the values tended to return within the normal reference range values within 7 days after the race, our study suggests that there is no permanent structural damage at the myocardium level. [less ▲]

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