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See detailA TMS–EEG contribution to the multimodal assessment of brain connectivity and consciousness
BODART, Olivier ULiege

Doctoral thesis (2017)

Patients with chronic disorders of consciousness make a challenging population. On the clinical side, establishing an accurate diagnosis is arduous, as the signs of consciousness can be subtle, or even ... [more ▼]

Patients with chronic disorders of consciousness make a challenging population. On the clinical side, establishing an accurate diagnosis is arduous, as the signs of consciousness can be subtle, or even undetectable behaviourally. Both the families and the caregivers need truthful information to make tough decisions about the patient’s management. Transcranial magnetic stimulation, coupled with high-density electroencephalography, is a promising technique to improve our diagnostic ability. The perturbational complexity index derived from this technique is able to distinguish between unconscious and conscious conditions. Its specificity remains to be determined. On the scientific side, the long-standing quest to discover the neural correlates of consciousness is still ongoing. Patients with disorders of consciousness have structural brain damage, and several areas may lose their ability to causally interact in complex patterns with long distance structure. The relation between this ability and structural integrity remains undetermined, despite a vast amount of neuroimaging studies on several networks and connectivities in this population. Our objectives are i) to cross-validate the perturbational complexity index with other neuroimaging techniques, and to determine its specificity, and ii) to determine the relation between global structural integrity and the brain global ability to sustain complex long-range interactions. To do so, we first combined transcranial magnetic stimulation with fluoro-deoxyglucose positron emission tomography, a validated technique studying the brain metabolism, in a population of patients behaviourally characterized by repeated assessments with the gold standard scale, the coma recovery scale – revised. To meet our second objective, we computed and compared the perturbational complexity index and the global fractional anisotropy, a magnetic resonance imaging marker of structural integrity, in patients and in healthy subjects. We found an excellent congruence between electrophysiological and metabolic results in our first study, even in behaviourally unconscious patients showing indirect signs of consciousness. In our second study, we demonstrated that structural integrity largely correlated with the perturbational complexity index, and did not depend on the time since onset or the aetiology. This confirms the diagnostic value of transcranial magnetic stimulation and the perturbational complexity index. It is not only sensitive at the single subject level, but also highly specific. It can detect covert signs of consciousness, as confirmed by other neuroimaging techniques. As such, it could be integrated in diagnostic algorithms and improve their accuracy, leading to better management of these patients. Moreover, the brain’s ability to sustain complex long-range interactions is highly dependant on the global structural integrity. By looking further in detail at the local correlation between these two parameters, our understanding of the emergence of consciousness from fixed structure with variable connectivity would improve. This would be one step forward in the quest for the neural correlates of consciousness. [less ▲]

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See detailElectrification and DRC
Ernst, Damien ULiege

Conference given outside the academic context (2017)

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See detailThe 4th power
George, Philippe ULiege

Scientific conference (2017, November 06)

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See detailStéréotypes du racisme ordinaire
Debras, François ULiege

Conference given outside the academic context (2017)

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See detailRaman Chemical Imaging in Kidney Stone Analysis
Castiglione, Vincent ULiege; Sacre, Pierre-Yves ULiege; CAVALIER, Etienne ULiege et al

Poster (2017, November 02)

Background: The structure of kidney stones might provide clinical useful information in addition to the stone composition. The Raman chemical imaging (RCI) is a new technology used for the production of ... [more ▼]

Background: The structure of kidney stones might provide clinical useful information in addition to the stone composition. The Raman chemical imaging (RCI) is a new technology used for the production of two-dimensions maps of the constituents' distribution in samples. We aimed at determining the use of RCI in urinary stone analysis. Methods: Twelve calculi were analyzed by RCI using a confocal Raman microspectrophotometer. They were selected according to their heterogeneous composition and morphology. Prior to the analysis, samples were sliced and milled in order to detect the nucleus of the stones and having a smooth surface. RCI was performed on the whole section of stones. Once acquired, the data were baseline corrected and analyzed by MCR-ALS. Results were then compared to the spectra obtained by Fourier Transform Infrared spectroscopy, the gold standard method for the determination of urolithiasis composition. Results: RCI succeeded in identifying all the chemical components contained in each sample, including monohydrate and dihydrate calcium oxalate, anhydrous and dihydrate uric acid, apatite, struvite, brushite, whitlockite and ammonium urate. However, proteins couldn't be detected because of the huge autofluorescence background and the small concentration of these poor Raman scatterers. Carbapatite and calcium oxalate were correctly detected even when they represented less than 5 percent of the whole stones, allowing the detection of very small structures like Randall's plaques. Moreover, RCI provided the distribution of components within the stones. The nuclei were accurately identified, as well as thin layers of other components. Conversion of dihydrate to monohydrate calcium oxalate was correctly observed in the center of one sample. Conclusion: RCI showed a good accuracy in comparison with infrared spectroscopy in identifying components of kidney stones. In addition, RCI is nondestructive enabling the storage of samples. This analysis was also useful in determining the organization of components within stones, which help locating constituents in low quantity, such as nuclei. However, this analysis is time-consuming, which makes it more suitable for research studies rather than routine analysis. [less ▲]

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See detailUp and downs of a magnetic oblique rotator viewed at high resolution
Nazé, Yaël ULiege; Zhekov, S. A.; Ud-Doula, A.

in The Lives and Death-Throes of Massive Stars (2017, November 01)

In 2006, the Of?p star HD191612 became the second O-star where a magnetic field was discovered. It provided a benchmark to understand the Of?p phenomenon as a whole. Ten years later, an X-ray monitoring ... [more ▼]

In 2006, the Of?p star HD191612 became the second O-star where a magnetic field was discovered. It provided a benchmark to understand the Of?p phenomenon as a whole. Ten years later, an X-ray monitoring performed at high-resolution reveals the behaviour of the hottest magnetospheric plasma: it is located at ~ 2R [SUB]⊙[/SUB], hot but not extreme (log(T) ~ 7), producing unshifted lines, and displaying a very repetitive variability. A direct comparison with simulations yields an overall good agreement, with only a few further improvements needed. [less ▲]

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See detailThe supergiant O + O binary system HD 166734: a new study
Gosset, Eric ULiege; Mahy, Laurent ULiege; Damerdji, Yassine ULiege et al

in The Lives and Death-Throes of Massive Stars (2017, November 01)

We present here a modern study of the radial velocity curve and of the photometric light curve of the very interesting supergiant O7.5If + O9I(f) binary system HD 166734. The physical parameters of the ... [more ▼]

We present here a modern study of the radial velocity curve and of the photometric light curve of the very interesting supergiant O7.5If + O9I(f) binary system HD 166734. The physical parameters of the stars and the orbital parameters are carefully determined. We also perform the analysis of the observed X-ray light curve of this colliding-wind binary. [less ▲]

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See detailInvestigating the Magnetospheres of Rapidly Rotating B-type Stars
Fletcher, C. L.; Petit, V.; Nazé, Yaël ULiege et al

in The Lives and Death-Throes of Massive Stars (2017, November 01)

Recent spectropolarimetric surveys of bright, hot stars have found that ~10% of OB-type stars contain strong (mostly dipolar) surface magnetic fields (~kG). The prominent paradigm describing the ... [more ▼]

Recent spectropolarimetric surveys of bright, hot stars have found that ~10% of OB-type stars contain strong (mostly dipolar) surface magnetic fields (~kG). The prominent paradigm describing the interaction between the stellar winds and the surface magnetic field is the magnetically confined wind shock (MCWS) model. In this model, the stellar wind plasma is forced to move along the closed field loops of the magnetic field, colliding at the magnetic equator, and creating a shock. As the shocked material cools radiatively it will emit X-rays. Therefore, X-ray spectroscopy is a key tool in detecting and characterizing the hot wind material confined by the magnetic fields of these stars. Some B-type stars are found to have very short rotational periods. The effects of the rapid rotation on the X-ray production within the magnetosphere have yet to be explored in detail. The added centrifugal force due to rapid rotation is predicted to cause faster wind outflows along the field lines, leading to higher shock temperatures and harder X-rays. However, this is not observed in all rapidly rotating magnetic B-type stars. In order to address this from a theoretical point of view, we use the X-ray Analytical Dynamical Magnetosphere (XADM) model, originally developed for slow rotators, with an implementation of new rapid rotational physics. Using X-ray spectroscopy from ESA's XMM-Newton space telescope, we observed 5 rapidly rotating B-types stars to add to the previous list of observations. Comparing the observed X-ray luminosity and hardness ratio to that predicted by the XADM allows us to determine the role the added centrifugal force plays in the magnetospheric X-ray emission of these stars. [less ▲]

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See detailX-rays from colliding winds in massive binaries
Nazé, Yaël ULiege; Rauw, Grégor ULiege

in The Lives and Death-Throes of Massive Stars (2017, November 01)

In a massive binary, the strong shock between the stellar winds may lead to the generation of bright X-ray emission. While this phenomenon was detected decades ago, the detailed study of this emission was ... [more ▼]

In a massive binary, the strong shock between the stellar winds may lead to the generation of bright X-ray emission. While this phenomenon was detected decades ago, the detailed study of this emission was only made possible by the current generation of X-ray observatories. Through dedicated monitoring and observations at high resolution, unprecedented information was revealed, putting strong constraints on the amount and structure of stellar mass-loss. [less ▲]

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See detailArpenter l’Histoire pour mieux maîtriser la temporalité de l’histoire en classe du secondaire. Etude de cas (2013-2015) et programme de recherche (2017-)
Jadoulle, Jean-Louis ULiege

Scientific conference (2017, November 01)

Cette étude de cas tente d’évaluer l’impact d’un dispositif d’enseignement sur la maitrise de la temporalité historienne ; ce dispositif est conçu sous la forme de parcours diachroniques successifs ou « ... [more ▼]

Cette étude de cas tente d’évaluer l’impact d’un dispositif d’enseignement sur la maitrise de la temporalité historienne ; ce dispositif est conçu sous la forme de parcours diachroniques successifs ou « parcours chronologiques emboités » (Jadoulle, 2008, 2015). Elle a été conduite en Belgique francophone avec un enseignant et compare, à deux années d’intervalle, la maitrise de la temporalité historienne par des élèves de 4e année (16 ans). Ceux-ci composent deux cohortes : la première a été évaluée en 2013 et avait bénéficié d’un mode d’enseignement chronologique de la période qui va de l’arrivée de Colomb en Amérique au Congrès de Vienne (1815) ; la seconde a été évaluée en 2015 et avait bénéficié d’un enseignement de cette même période, par le même professeur, mais sous la forme de plusieurs « parcours chronologiques emboités » , chacun de ces parcours faisant ensuite l’objet d’une mise en perspective synchronique avec les autres. Les résultats indiquent que le dispositif dit des « parcours chronologiques emboités » améliore la maitrise de la temporalité historienne. Ils améliorent en particulier la capacité à établir une succession ou une diachronie, à identifier des changements et des continuités et à repérer des synchronies. [less ▲]

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See detailEssay of Siganus sutor aquaculture in Madagascar: for promising alternative activity for traditional fishermen
Ravelohasina, Helga; Rasolofonirina, R.; Mahafina, J. et al

Poster (2017, November)

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See detailCytotoxic T-lymphocyte-associated protein 4-Ig effectively controls immune activation and inflammatory disease in a novel murine model of leaky severe combined immunodeficiency.
Humblet-Baron, Stephanie; Schonefeldt, Susann; Garcia-Perez, Josselyn E. et al

in Journal of Allergy and Clinical Immunology (The) (2017), 140(5), 1394-1403

BACKGROUND: Severe combined immunodeficiency can be caused by loss-of-function mutations in genes involved in the DNA recombination machinery, such as recombination-activating gene 1 (RAG1), RAG2, or DNA ... [more ▼]

BACKGROUND: Severe combined immunodeficiency can be caused by loss-of-function mutations in genes involved in the DNA recombination machinery, such as recombination-activating gene 1 (RAG1), RAG2, or DNA cross-link repair 1C (DCLRE1C). Defective DNA recombination causes a developmental block in T and B cells, resulting in high susceptibility to infections. Hypomorphic mutations in the same genes can also give rise to a partial loss of T cells in a spectrum including leaky severe combined immunodeficiency (LS) and Omenn syndrome (OS). These patients not only experience life-threatening infections because of immunodeficiency but also experience inflammatory/autoimmune conditions caused by the presence of autoreactive T cells. OBJECTIVE: We sought to develop a preclinical model that fully recapitulates the symptoms of patients with LS/OS, including a model for testing therapeutic intervention. METHODS: We generated a novel mutant mouse (Dclre1cleaky) that develops a LS phenotype. Mice were monitored for diseases, and immune phenotype and immune function were evaluated by using flow cytometry, ELISA, and histology. RESULTS: Dclre1cleaky mice present with a complete blockade of B-cell differentiation, with a leaky block in T-cell differentiation resulting in an oligoclonal T-cell receptor repertoire and enhanced cytokine secretion. Dclre1cleaky mice also had inflammatory symptoms, including wasting, dermatitis, colitis, hypereosinophilia, and high IgE levels. Development of a preclinical murine model for LS allowed testing of potential treatment, with administration of cytotoxic T-lymphocyte-associated protein 4-Ig reducing disease symptoms and immunologic disturbance, resulting in increased survival. CONCLUSION: These data suggest that cytotoxic T-lymphocyte-associated protein 4-Ig should be evaluated as a potential treatment of inflammatory symptoms in patients with LS and those with OS. [less ▲]

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See detailSiSTEM, a Model for the Simulation of Short-Term Electricity Markets
Mathieu, Sébastien; Petitet, Marie; Perrot, Marie et al

E-print/Working paper (2017)

The aim of this document is to present SiSTEM, a multi-level simulation model of European short-term electricity markets, covering day-ahead and intraday exchanges to balancing activations in real-time ... [more ▼]

The aim of this document is to present SiSTEM, a multi-level simulation model of European short-term electricity markets, covering day-ahead and intraday exchanges to balancing activations in real-time, and imbalance settlement. In this model, power companies interact by making offers, notifying their positions to the system operator and impacting the balance of the electric system. The system operator activates balancing energy to restore the balance of the system, using all balancing activation offers, including from balancing reserves. Imbalance settlement implies bidirectional transactions between the system operator and power companies depending on the direction of their imbalance. A simulation of the model is performed by sequentially considering each time step and simulating actors’ decisions. The objective of this model is to understand the problems behind decisions of the actors within the short-term electrical system operation, to provide insights on how these problems can be solved through market design and to see how the decisions are linked together to shape a coherent system. This paper presents different simulation cases of an illustrative system in order to portray main features of the model in a practical and effective manner. In particular, the results show the importance of considering steady-state constraints and notice delays of generation units when looking at short-term issues. Future works could use this model to provide quantitative assessments of short-term market designs. [less ▲]

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See detailFixation Techniques in Lower Extremity Syndesmotic Injuries
D'Hooghe, Pieter; York, PJ; Kaux, Jean-François ULiege et al

in Foot & Ankle International (2017), 38(11), 1278-1288

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See detailEffect of whole body cryotherapy interventions on health-related quality of life in fibromyalgia patients: A randomized controlled trial
Vitenet, Mathilde; Tubez, François ULiege; Marreiro, Anthony et al

in Complementary Therapies in Medicine (2017), 36

Introduction: Although fibromyalgia syndrome (SFM) affects 2–4 percent of adults, research has not identified a preferred therapeutic option for patients worldwide yet. Based on recent findings, it can be ... [more ▼]

Introduction: Although fibromyalgia syndrome (SFM) affects 2–4 percent of adults, research has not identified a preferred therapeutic option for patients worldwide yet. Based on recent findings, it can be expected that whole body cryotherapy can improve health-reported quality of life by alleviating the symptoms of musculoskeletal pain and fatigue. Objective: Our aim was to determine whether whole body cryotherapy only can result in improved perceived health and quality of life in fibromyalgia patients. Methods: 24 patients with fibromyalgia diagnosis were randomized into 2 groups (n= 11 in the whole body cryotherapy group, n=13 in the control group). In the whole body cryotherapy group, 10 sessions of whole body cryotherapy were performed (in addition to usual care) in a standard cryotherapy room over a duration of 8 days. Subjects in the control group did not change anything in their everyday activities. Quality of life was assessed just before and one month after treatment. Results: Compared with the control group, patients in the whole body cryotherapy group reported significantly improved for health-reported quality of life. These effects lasted for at least one month following intervention. Conclusion: Based on these findings, whole body cryotherapy can be recommended as an effective clinically adjuvant approach in the improvement of health-related quality of life in fibromyalgia patients. [less ▲]

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