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See detailHas the fight against international terrorism undermined European data protection standards? A special regard to the perspectives of the transatlantic relationship
Berardo, Fiammetta ULg

Doctoral thesis (2013)

Il s’agit d'une analyse des accords PNR (Passenger Name Records) entre l’Union Européenne et les Etats Unis et plus en général des changements aux lois de protection de la vie privée qui sont intervenus ... [more ▼]

Il s’agit d'une analyse des accords PNR (Passenger Name Records) entre l’Union Européenne et les Etats Unis et plus en général des changements aux lois de protection de la vie privée qui sont intervenus dans les dernières années, surtout à la suite des événements du onze septembre 2001. La réflexion porte donc sur l’évolution du concept de protection des données personnelles vis à vis des nouveaux instruments de collecte d’informations et d’enquête. [less ▲]

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See detailSustainability Management Practices: An International Comparison
Crutzen, Nathalie ULg

Conference given outside the academic context (2013)

Detailed reference viewed: 23 (2 ULg)
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See detailObservation de l’atmosphère de Vénus par le spectromètre imageur VIRTIS-M de Venus-Express : analyse des émissions nocturnes de O2 et OH
Soret, Lauriane ULg

Doctoral thesis (2013)

Venus, the second planet of the solar system, has a very dense CO2-dominated atmosphere. Above 50 km, its dynamics is usually decomposed into two main circulation patterns. The first one, the Retrograde ... [more ▼]

Venus, the second planet of the solar system, has a very dense CO2-dominated atmosphere. Above 50 km, its dynamics is usually decomposed into two main circulation patterns. The first one, the Retrograde Superrotating Zonal (RSZ) circulation, controls atmospheric layers below 65 km of altitude. This motion is related to the retrograde rotation of the planet. The second circulation operates above 120 km. This Subsolar-Antisolar (SS-AS) circulation generates a flux from the dayside to the nightside of Venus. It originates from the strong temperature gradients at the top of the atmospheric layer. Between 65 and 120km, the circulation is more complex and no in situ measurement has been performed to study this region of the atmosphere. However, it is possible to use minor atmospheric constituents and their spectral signatures as dynamic tracers to better understand this region. For example, oxygen atoms are produced by photodissociation of CO2 molecules which dominate the Venusian atmosphere. They are then carried by the SS-AS circulation to the planet nightside, where they recombine into O2 molecules in several metastable excited states. Their de-excitation produces measurable emissions, named nightglow which may be qualitatively investigated. This thesis focuses on the study of these emission phenomena. Data have been acquired by the Venus Express spacecraft, in a quasi-polar elliptical orbit around Venus since April 2006. More specifically, observations have been made with the VIRTIS-M instrument, a multispectral imager. As VIRTIS observes in the visible and near infrared domains, some molecular oxygen and hydroxyl transitions can be detected in the data. The main goal of this study has been to extract quantitative information from these observations and to analyze both the density of constituents (such as excited molecular oxygen, atomic oxygen and ozone) and the dynamical processes involved in this region of the Venusian atmosphere. In a first part, data acquired at 1.27 µm in nadir mode have been processed and analyzed in order to study the O2(a1Δg→X3Σg-) infrared atmospheric transition. Data processing consists in correcting the geometrical effects associated with the view angle, the cloud reflection and the thermal contribution. Data analysis following emission patches in individual data sets points out a large variability of the phenomenon, both in terms of brightness and localization. Emission peaks vary from 0.5 to 6 MegaRayleighs (MR) and may be observed over the entire southern hemisphere of the planet, which is the observable part in nadir mode. However, once the individual data are grouped together to generate a statistical map, our analysis shows that the emission at 1.27 µm is located around the antisolar point, which confirms the SS-AS circulation predominance. This map is improved in the northern hemisphere by adding vertical intensity profiles derived from limb images. These profiles are deconvolved to take into account VIRTIS-M spatial resolution and transformed by the Abel inversion to get a local profile of the volume emission rate. A vertical integration of these profiles simulates a nadir observation and completes the bidimensional statistical map of the O2(a1Δg) emission. The intensity reaches 1.6 MR at the antisolar point and the mean nightside value is 0.5 MR. This map, combined with limb profiles, allows to generate a tridimensional distribution of the emission. It shows that the emitting layer is located at ~96.5 km. These results, combined with a tridimensional distribution of the CO2 density (generated with the VTS3 model or measurements from the SPICAV spectrometer on board Venus Express) allows to generate a 3-D map of the atomic oxygen density. The mean nightside density value is 2.0x1011 cm-3 at 103.4 km. This empirical map validates the VTGCM model, as no measurements of the atomic oxygen density had ever been performed in this region of the Venus atmosphere. Other oxygen transitions have been detected in the visible domain (Migliorini et al., 2012): the Herzberg II (c1Σu-→X3Σg-) and Chamberlain (A’3Δu→a1Δg) transitions. Using CO2 and O density profiles derived from our previous study, these transitions have been modeled. Some reaction parameters, whose laboratory measurements are insufficient or inexistent, have thus been estimated. The distribution of the Herzberg I (A3Σu→X3Σg-) transition has also been simulated. Other emission limb profiles have also been extracted from the VIRTIS-M database: the OH(Δv=1) and OH(Δv=2) Meinel emission bands of the hydroxyl molecule. First, these profiles have been processed to subtract a stray signal. The simultaneous statistical study shows that IOH(Δv=1)= 0.60 MR and IOH(Δv=2)=0.23 MR at ~97 km and that their intensity are correlated. The spectral analysis with synthetic spectra demonstrates that only v’≤4 vibrational levels are populated. These emissions have been modeled taking into account excited OH production, deactivation by collisions and reaction and spontaneous emission loss. The CO2 and O density profiles derived from the oxygen study have been used. The quenching coefficients have been adjusted to consider the temperature of the emitting layer and two quenching mechanisms by CO2 have been implemented. This model showed that collisional quenching by single quantum jump (Δv=1) best reproduces the observations. Likewise, an ozone density of 5.8x106 cm-3 at 96.5 km (for the best case) is in good agreement with the recent SPICAV O3 detection. Finally, the study of simultaneous OH(Δv=1) and O2(a1Δg) limb profiles showed a very high spatial correlation of these two emissions. This result has been explained by the role of atomic oxygen as a common precursor for the formation of both molecular oxygen and hydroxyl. [less ▲]

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See detailLe cinéma politique a-t-il besoin d'un alphabétiseur? (Enzensberger, Kluge, Negt)
Hamers, Jérémy ULg

Scientific conference (2013, March 28)

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See detailLe management public dans la sphère scolaire : émergence des pratiques de médiation scolaire au sein de trois « mondes » d’acteurs
Gérard, Julie ULg

Conference (2013, March 28)

This article aims to examine changing practices of school mediation in three “worlds” of actors – the educational world, the manager world and the “living together” world – crossing three fields of ... [more ▼]

This article aims to examine changing practices of school mediation in three “worlds” of actors – the educational world, the manager world and the “living together” world – crossing three fields of research in sociology: the interactionism, the sociology of public management, and the sociology of school. Traditionally performed by the institutional mediator of the school or, occasionally, by a local mediator, the variety of contemporary mediation practices appears as a consequence of the organizational challenges of New Public Management of Belgium. I will first explain the background of the changes which occurred in the educational field and examine the changing role of school stakeholders. Then, I will present three case studies which illustrate how schools are anchored in the three “worlds” of actors mentioned above. Finally, I will discuss the results giving the first lines of interpretation of this school evolution. [less ▲]

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See detailThe Semantic-syntactic Interface
Winand, Jean ULg

Conference (2013, March 28)

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See detailKDIGO – prise en charge de l’hypertension artérielle en dialyse
Krzesinski, Jean-Marie ULg

Conference (2013, March 28)

1. A lower target may be chosen in CKD patients with proteinuria but after individualized risk-benefit assessment. The price to pay is a need for a higher number of antiHTA drugs and a risk of more ... [more ▼]

1. A lower target may be chosen in CKD patients with proteinuria but after individualized risk-benefit assessment. The price to pay is a need for a higher number of antiHTA drugs and a risk of more frequent side-effects. 2. Confirmation of a high BP level is necessary through out-of-the clinic BP measurement In CKD, ABPM offers night-time BP information useful for CV and renal risk evaluation. BP variability is a new point to be considered in the future. Proteinuria but also other specific risk factors (Phosphate, anemia, inflammation,..) should be integrated in the management of hypertension in CKD [less ▲]

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See detailCharacteristics of Near-Death Experiences Memories as Compared to Real and Imagined Events Memories
Thonnard, Marie ULg; Charland-Verville, Vanessa ULg; Brédart, Serge ULg et al

in PLoS ONE (2013), 8(3),

Since the dawn of time, Near-Death Experiences (NDEs) have intrigued and, nowadays, are still not fully explained. Since reports of NDEs are proposed to be imagined events, and since memories of imagined ... [more ▼]

Since the dawn of time, Near-Death Experiences (NDEs) have intrigued and, nowadays, are still not fully explained. Since reports of NDEs are proposed to be imagined events, and since memories of imagined event have, on average, fewer phenomenological characteristics than real events memories, we here compared phenomenological characteristics of NDEs reports with memories of imagined and real events. We included three groups of coma survivors (8 patients with NDE as defined by the Greyson NDE scale, 6 patients without NDE but with memory of their coma, 7 patients without memories of their coma) and a group of 18 age-matched healthy volunteers. Five types of memories were assessed using Memory Characteristics Questionnaire (MCQ – Johnson et al., 1988): target memory (NDE for NDE memory group, coma memory for coma memory group, and first childhood memory for no memory and control groups), old and recent real event memories and old and recent imagined event memories. Since NDEs are known to have high emotional content, participants were requested to choose the most emotionally salient memories for both real and imagined recent and old event memories. Results showed that, in NDE memories group, NDE memories have more characteristics than memories of imagined and real events (p<0.02). NDE memories contain more self-referential and emotional information and have better clarity than memories of coma (all p<0.02). The present study showed that NDE memories contain more characteristics than real event memories and coma memories. Thus, this suggests that they cannot be considered as imagined event memories. On the contrary, their physiological origins could lead them to be really perceived although not lived in the reality. Further work is needed to better understand this phenomenon. [less ▲]

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See detailCharacterization of ionospheric irregularities and their influence on high-accuracy positioning with GPS over mid-latitudes
Wautelet, Gilles ULg

Doctoral thesis (2013)

Over the last decade came major breakthroughs in satellite navigation and positioning, due to the development of precise positioning techniques based on Global Positioning System (GPS) signals. Modern ... [more ▼]

Over the last decade came major breakthroughs in satellite navigation and positioning, due to the development of precise positioning techniques based on Global Positioning System (GPS) signals. Modern processing methods, such as the Real-Time Kinematics (RTK), allow the GPS user to determine its position in real-time with an accuracy of a few centimeters. The success of these algorithms relies on the cancellation and/or the mitigation of the various errors affecting signal propagation. Among these errors is the delay due to the ionospheric refraction. More particularly, the presence of irregularities in the ionospheric plasma is responsible for positioning errors reaching several (deci)meters. As a result, there is a growing demand from GPS user communities (such as land surveyors or civil engineers) to be informed, if possible in advance, of the occurrence of irregularities that might impact on their positioning solution. Based on a ten years GPS dataset collected over Belgium, this thesis aims at assessing, understanding and modeling the occurrence of ionospheric irregularities as well as estimating their effects in terms of positioning accuracy. Firstly, we carry out a climatological study of irregularities to identify and characterize the most recurrent features. We can distinguish two main irregularity types: those due to space weather events (such as Coronal Mass Ejections – CMEs – or solar flares) and the others, constituting the bulk of irregularities observed at a single station and referred to as “quiet-time” irregularities, as they occur during quiet geomagnetic conditions. These latter are then divided into two groups: the first is made up of Medium-Scale Traveling Ionospheric Disturbances (MSTIDs) which occur during autumn/winter daytime. In the second group are the summer nighttime irregularities, which are rapid fluctuations of the Total Electron Content (TEC) probably associated with spread-F phenomenon. Next, we develop a model of quiet-time irregularity occurrence, based on a statistical analysis of the aforementioned dataset. Computations rely on several mathematical modeling tools, such as the Principal Component Analysis (PCA), the Generalized Least-Squares (GLS) algorithm and the AutoRegressive and Moving Average (ARMA) method. The resulting climatological model is made up of two components reproducing daily profile as well as secular variations of the ionospheric variability for a typical GPS station in Belgium. The last part of this work deals with the impact of irregularities on relative positioning. This technique allows the measurement of the vector (called baseline) joining the receiver (user station) to a reference station whose position is accurately known. More precisely, we assess the effect of baseline length and orientation during the occurrence of MSTIDs and geomagnetic storms through the processing of the Belgian Dense Network, made up of 66 dual-frequency GPS stations. Finally, the relationship between positioning error and the presence of ionospheric irregularities detected at a single station is investigated, filling the gap between the scientific and the GPS-user communities. [less ▲]

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See detailCyrtodactylus sanook (Squamata: Gekkonidae), a new cave-dwelling gecko from Chumphon Province, southern Thailand
Pauwels, Olivier S.G.; Sumontha, Montri; Latinne, Alice ULg et al

in Zootaxa (2013), 3635(3), 275-285

Detailed reference viewed: 19 (1 ULg)
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See detailGravitationall lensing evidence against extended dark matter halos
Magain, Pierre ULg; Chantry, Virginie ULg

E-print/Working paper (2013)

It is generally thought that galaxies are embedded in dark matter halos extending well beyond their luminous matter. The existence of these galactic halos is mainly derived from the larger than expected ... [more ▼]

It is generally thought that galaxies are embedded in dark matter halos extending well beyond their luminous matter. The existence of these galactic halos is mainly derived from the larger than expected velocities of stars and gas in the outskirts of spiral galaxies. Much less is known about dark matter around early-type (elliptical or lenticular) galaxies. We use gravitational lensing to derive the masses of early-type galaxies deflecting light of background quasars. This provides a robust measurement of the total mass within the Einstein ring, a circle whose diameter is comparable to the separation of the different quasar images. We find that the mass-to-light ratio of the lensing galaxies does not depend on radius, from inner galactic regions out to several half-light radii. Moreover, its value does not exceed the value predicted by stellar population models by more than a factor two, which may be explained by baryonic dark matter alone, without any need for exotic matter. Our results thus suggest that, if dark matter is present in early-type galaxies, its amount does not exceed the amount of luminous matter and its density follows that of luminous matter, in sharp contrast to what is found from rotation curves of spiral galaxies. [less ▲]

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See detailLaplace et le développement des politiques scientifiques en Europe
Grell, Chantal; Vandersmissen, Jan ULg

Conference (2013, March 27)

Detailed reference viewed: 12 (1 ULg)
See detailL’indice paysager Caulerpa racemosa “I.Ca.r”
Cariou, Nicolas; Chery, Aurélia; Jousseaume, Matthieu et al

in Ifremer (Ed.) CARtographie des HAbitats Marins Benthiques : de l'Acquisition à la Restitution (2013, March 27)

Depuis 2002, l’algue invasive Caulerpa racemosa var. cylindracea a été signalée au niveau de la Corse. Elle apparaît pour la première fois, en 2008, au niveau de la baie de Calvi (Corse). Depuis cette ... [more ▼]

Depuis 2002, l’algue invasive Caulerpa racemosa var. cylindracea a été signalée au niveau de la Corse. Elle apparaît pour la première fois, en 2008, au niveau de la baie de Calvi (Corse). Depuis cette époque, le nombre et la surface des sites envahis augmentent. L'analyse fine de l'évolution spatio-temporelle de sa distribution dans la zone prospectée confirme que C. racemosa colonise d'abord les sites profonds. A partir des différents stades de colonisation, un indice paysager (Indice Caulerpa racemosa: "I.Ca.r") adapté à la plongée en scaphandre autonome a été élaboré. "I.Ca.r" qui tient compte de l'expérience du plongeur, du type de substrat et de la superficie colonisée est un code à 8 caractères. Il permet une comparaison spatiale de sites colonisés et également une analyse de l'évolution temporelle de la colonisation. Mis au point en Baie de Calvi, l'indice paysager "I.Ca.r" peut être appliqué sur la Corse et sur l'ensemble de La Méditerranée. La méthodologie simple, résumée sur une fiche pourrait être distribuée dans les clubs de plongée et les informations envoyées au réseau Caulerpe par exemple. [less ▲]

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See detailNeural fate of Mesenchymal Stem Cells and Neural Crest Stem Cells : Which ways to get neurons for cell therapy purpose ?
Neirinckx, Virginie ULg; Coste, Cécile ULg; Rogister, Bernard ULg et al

in Trends in cell signaling pathways in neuronal fate decision (2013)

Detailed reference viewed: 37 (11 ULg)
See detailL’eau dans l’univers
Jehin, Emmanuel ULg; Javaux, Emmanuelle ULg; Magain, Pierre ULg et al

Conference given outside the academic context (2013)

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See detailPerception et confort acoustiques des Systèmes de Traitement d'Air
Minard, Antoine ULg

Doctoral thesis (2013)

This thesis addresses the perceived acoustic comfort of Air-Treatment Systems (ATS), such as air-conditioners installed in offices, by taking into account the environmental factors related to the specific ... [more ▼]

This thesis addresses the perceived acoustic comfort of Air-Treatment Systems (ATS), such as air-conditioners installed in offices, by taking into account the environmental factors related to the specific context of ATS usage. The only existing standard to evaluate the sounds emitted by ATS, which is the emitted sound level in dBA, is only loosely related to perception. Therefore, the need of manufacturers for a more reliable standard arises. This implies a thorough study of the perception of the sound of ATS as it is emitted. A precise methodology was then followed: it includes first collecting a high number of ATS sound recordings, up to finally developing a robust metrics to predict the perceived sound quality. For that purpose, different perceptual categories were first identified to constitute the recording database of ATS sounds. A corpus considered as fully representative of the different types of emitted sounds was then extracted from the recording database. Current principles of musical timbre description have already proved to be adequate to other types of environmental sounds; by applying these principles, the relevant auditive attributes for the corpus perceptual description were identified. In order to develop an efficient sound quality predictor through audio features calculation, prominent features based on these auditive attributes were identified that explain the listeners' preferences among ATS sounds. The ecological context of ATS was examined in a second step. Two environmental factors were addressed in the context of ATS sound quality evaluation to ponder their importance in the listeners' perception. As the ATS under study are exclusively indoor systems designed for offices, the effect of reverberation on sound quality evaluation was first studied; for that purpose, an auralization tool was used to simulate room acoustic response. The influence of listeners' attention context on perceived sound quality was then evaluated through a comparative study of various listening conditions. As a matter of fact, the sound emitted by ATS in real conditions is perceived as a perturbation of current activities. It is therefore relevant to evaluate how deeply the degree of attention related to the sound affects listeners as regards their perception of acoustic quality. Eventually, the relevance of the proposed sound quality predictor to comfort perception was assessed in conditions more ecologically representative than usual laboratory environment. [less ▲]

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See detailImpacts of a unicellular mechanism on network behaviors
Dethier, Julie ULg; Drion, Guillaume; Franci, Alessio et al

Conference (2013, March 26)

Parkinson’s disease (PD) is a neurodegenerative disorder af- fecting the basal ganglia (BG), a set of small subcortical nervous system nuclei. The hallmark of the disease is a dopaminergic denervation of ... [more ▼]

Parkinson’s disease (PD) is a neurodegenerative disorder af- fecting the basal ganglia (BG), a set of small subcortical nervous system nuclei. The hallmark of the disease is a dopaminergic denervation of the striatum—the input stage of the BG—altering information patterns along movement- related ganglia-mediated pathways in the brain. Severe mo- tor symptoms result from the pathological state: tremor at rest, bradykinesia—the slowness and impaired scaling of voluntary movement—and akinesia—the poverty of volun- tary movements. It is still unclear how dopamine depletion causes those motor symptoms. Experimental studies have shown that abnormally synchronized oscillatory activities— rhythmic bursting activity at the unicellular level and beta frequency band (from 8 to 30Hz) oscillations at the network level—emerge in PD at multiple levels of the BG-cortical loops and correlate with motor symptoms. The mechanisms underlying these pathological beta oscillations remain elu- sive. We propose that a cellular mechanism generates burst- ing activities and beta band oscillations at the network level. [less ▲]

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