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See detailPerspectives for observing hot massive stars with XMM-Newton in the years 2017-2027
Rauw, Grégor ULg

in Astronomische Nachrichten (2017), 338

XMM-Newton has deeply changed our picture of X-ray emission of hot, massive stars. High-resolution X-ray spectroscopy as well as monitoring of these objects helped us gain a deeper insight into the ... [more ▼]

XMM-Newton has deeply changed our picture of X-ray emission of hot, massive stars. High-resolution X-ray spectroscopy as well as monitoring of these objects helped us gain a deeper insight into the physics of single massive stars with or without magnetic fields, as well as of massive binary systems, where the stellar winds of both stars interact. These observations also revealed a number of previously unexpected features that challenge our understanding of the dynamics of the stellar winds of massive stars. I briefly summarize the results obtained over the past 15 years and highlight the perspectives for the next decade. It is anticipated that coordinated (X-ray and optical or UV) monitoring and time-critical observations of either single or binary massive stars will become the most important topics in this field over the coming years. Synergies with existing or forthcoming X-ray observatories (NuSTAR, Swift, eROSITA) will also play a major role and will further enhance the importance of XMM-Newton in our quest for understanding the physics of hot, massive stars. [less ▲]

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See detailEvolutionary status of the Of?p star HD 148937 and of its surrounding nebula NGC 6164/5
Mahy, Laurent ULg; Hutsemekers, Damien ULg; Nazé, Yaël ULg et al

in Astronomy and Astrophysics (2017), 599(A61), 17

<BR /> Aims: The magnetic star HD 148937 is the only Galactic Of?p star surrounded by a nebula. The structure of this nebula is particularly complex and is composed, from the center out outwards, of a ... [more ▼]

<BR /> Aims: The magnetic star HD 148937 is the only Galactic Of?p star surrounded by a nebula. The structure of this nebula is particularly complex and is composed, from the center out outwards, of a close bipolar ejecta nebula (NGC 6164/5), an ellipsoidal wind-blown shell, and a spherically symmetric Strömgren sphere. The exact formation process of this nebula and its precise relation to the star's evolution remain unknown. <BR /> Methods: We analyzed infrared Spitzer IRS and far-infrared Herschel/PACS observations of the NGC 6164/5 nebula. The Herschel imaging allowed us to constrain the global morphology of the nebula. We also combined the infrared spectra with optical spectra of the central star to constrain its evolutionary status. We used these data to derive the abundances in the ejected material. To relate this information to the evolutionary status of the star, we also determined the fundamental parameters of HD 148937 using the CMFGEN atmosphere code. <BR /> Results: The Hα image displays a bipolar or "8"-shaped ionized nebula, whilst the infrared images show dust to be more concentrated around the central object. We determine nebular abundance ratios of N/O = 1.06 close to the star, and N/O = 1.54 in the bright lobe constituting NGC 6164. Interestingly, the parts of the nebula located further from HD 148937 appear more enriched in stellar material than the part located closer to the star. Evolutionary tracks suggest that these ejecta have occured 1.2-1.3 and 0.6 Myr ago, respectively. In addition, we derive abundances of argon for the nebula compatible with the solar values and we find a depletion of neon and sulfur. The combined analyses of the known kinematics and of the new abundances of the nebula suggest either a helical morphology for the nebula, possibly linked to the magnetic geometry, or the occurrence of a binary merger. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.Based in part on observations collected at the European Southern Observatory, in Chile. [less ▲]

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See detailReconnaissance of the TRAPPIST-1 exoplanet system in the Lyman-α line
Bourrier, V.; Ehrenreich, D.; Wheatley, P. J. et al

in Astronomy and Astrophysics (2017), 599

The TRAPPIST-1 system offers the opportunity to characterize terrestrial, potentially habitable planets orbiting a nearby ultracool dwarf star. We performed a four-orbit reconnaissance with the Space ... [more ▼]

The TRAPPIST-1 system offers the opportunity to characterize terrestrial, potentially habitable planets orbiting a nearby ultracool dwarf star. We performed a four-orbit reconnaissance with the Space Telescope Imaging Spectrograph onboard the Hubble Space Telescope to study the stellar emission at Lyman-α, to assess the presence of hydrogen exospheres around the two inner planets, and to determine their UV irradiation. We detect the Lyman-α line of TRAPPIST-1, making it the coldest exoplanet host star for which this line has been measured. We reconstruct the intrinsic line profile, showing that it lacks broad wings and is much fainter than expected from the stellar X-ray emission. TRAPPIST-1 has a similar X-ray emission as Proxima Cen but a much lower Ly-α emission. This suggests that TRAPPIST-1 chromosphere is only moderately active compared to its transition region and corona. We estimated the atmospheric mass loss rates for all planets, and found that despite a moderate extreme UV emission the total XUV irradiation could be strong enough to strip the atmospheres of the inner planets in a few billions years. We detect marginal flux decreases at the times of TRAPPIST-1b and c transits, which might originate from stellar activity, but could also hint at the presence of extended hydrogen exospheres. Understanding the origin of these Lyman-α variations will be crucial in assessing the atmospheric stability and potential habitability of the TRAPPIST-1 planets. [less ▲]

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See detailPolarimetric view of the changing type Seyfert galaxy ESO 362-G018.
Agis-Gonzalez, Beatriz ULg; Bagnulo, S.; Hutsemekers, Damien ULg et al

in Highlights on Spanish Astrophysics IX (2017, March 01)

ESO362-G018 is an active galactic nucleus (AGN) which is classified as a Seyfert 1.5 galaxy e.g. by Bennert et al. (2006), (black data set on figure 1). However, Parisi et. al (2009) found an optical ... [more ▼]

ESO362-G018 is an active galactic nucleus (AGN) which is classified as a Seyfert 1.5 galaxy e.g. by Bennert et al. (2006), (black data set on figure 1). However, Parisi et. al (2009) found an optical spectrum of this source which was taken during the 6dF Galaxy Survey, but it does not show the broad Balmer lines required to classify it as Seyfert 1 galaxy (red data set on figure 1). On the other hand, the results obtained by Agis-Gonzalez et al. (2014❩ in a X-ray analysis of this same source reveal that the inclination of ESO362- G018 i = 53° ± 5° is consistent with the picture of an AGN looked through the upper layers of a clumpy, dusty torus. Thus, according to the Unification Models of AGN and the clumpy nature of the torus, our interpretation of the different spectra is the following one. On 30th of January of 2003 (when the spectrum belonging to the 6dF survey was obtained), our line of sight intercepted a (or several aligned) torus clump(s) with much greater column density than its environment. Accordingly, the nucleus and the broad line region (❨BLR)❩ would be obscured. This allowed only the narrow emission lines to emerge from the narrow line region (NRL). Otherwise, on 18th of September of 2004 (when the spectrum by Bennert et al. 2006 was obtained) there is no clump to intercept and the BLR is not obscured so that the broad Balmer emission lines could be detected. [less ▲]

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See detailTwo massive rocky planets transiting a K-dwarf 6.5 parsecs away
Gillon, Michaël ULg; Demory, Brice-Olivier; Van Grootel, Valérie ULg et al

in Nature Astronomy (2017), 1

HD 219134 is a K-dwarf star at a distance of 6.5 parsecs around which several low-mass planets were recently discovered[SUP]1,2[/SUP]. The Spitzer Space Telescope detected a transit of the innermost of ... [more ▼]

HD 219134 is a K-dwarf star at a distance of 6.5 parsecs around which several low-mass planets were recently discovered[SUP]1,2[/SUP]. The Spitzer Space Telescope detected a transit of the innermost of these planets, HD 219134 b, whose mass and radius (4.5 M[SUB]⊕[/SUB] and 1.6 R[SUB]⊕[/SUB] respectively) are consistent with a rocky composition[SUP]1[/SUP]. Here, we report new high-precision time-series photometry of the star acquired with Spitzer revealing that the second innermost planet of the system, HD 219134c, is also transiting. A global analysis of the Spitzer transit light curves and the most up-to-date HARPS-N velocity data set yields mass and radius estimations of 4.74 ± 0.19 M[SUB]⊕[/SUB] and 1.602 ± 0.055 R[SUB]⊕[/SUB] for HD 219134 b, and of 4.36 ± 0.22 M[SUB]⊕[/SUB] and 1.511 ± 0.047 R[SUB]⊕[/SUB] for HD 219134 c. These values suggest rocky compositions for both planets. Thanks to the proximity and the small size of their host star (0.778 ± 0.005 R[SUB]⊙[/SUB])[SUP]3[/SUP], these two transiting exoplanets — the nearest to the Earth yet found — are well suited for a detailed characterization (for example, precision of a few per cent on mass and radius, and constraints on the atmospheric properties) that could give important constraints on the nature and formation mechanism of the ubiquitous short-period planets of a few Earth masses. [less ▲]

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See detailThe Future Prevalence of Sarcopenia in Europe: A Claim for Public Health Action.
Ethgen, Olivier ULg; Beaudart, Charlotte ULg; Buckinx, Fanny ULg et al

in Calcified Tissue International (2017), 100(3), 229-234

Sarcopenia is a major public health issue. To convince health policy makers of the emergency to invest in the sarcopenia field, it is of critical importance to produce reliable figures of the expected ... [more ▼]

Sarcopenia is a major public health issue. To convince health policy makers of the emergency to invest in the sarcopenia field, it is of critical importance to produce reliable figures of the expected burden of sarcopenia in the coming years. Age- and gender-specific population projections were retrieved until 2045 from the Eurostat online database (28 European countries). Age- and gender-specific prevalences of sarcopenia were interpolated from a study that compared prevalence estimates according to the different diagnostic cutoffs of the EWGSOP proposed definition. The reported prevalence estimates were interpolated between 65 and 100 years. Interpolated age- and gender-specific estimates of sarcopenia prevalence were then applied to population projections until 2045. Using the definition providing the lowest prevalence estimates, the number of individuals with sarcopenia would rise in Europe from 10,869,527 in 2016 to 18,735,173 in 2045 (a 72.4% increase). This corresponds to an overall prevalence of sarcopenia in the elderly rising from 11.1% in 2016 to 12.9% in 2045. With the definition providing the highest prevalence estimates, the number of individuals with sarcopenia would rise from 19,740,527 in 2016 to 32,338,990 in 2045 (a 63.8% increase), corresponding to overall prevalence rates in the elderly of 20.2% and 22.3% for 2016 and 2045, respectively. We showed that the number of sarcopenic patients will dramatically increase in the next 30 years, making consequences of muscle wasting a major public health issue. [less ▲]

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See detailUn regard comparatif sur les régionalismes africain et latino-américain
Santander, Sébastian ULg

in Interventions Economiques = Papers in Political Economy (2017)

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See detailINVESTIGATION DE LA QUALITE D’ANTIBIOTIQUES A BASE D'AMOXICILLINE DANS LE CADRE DE LA SURVEILLANCE DU MARCHE OFFICIEL ET PERIPHERIQUE DE QUELQUES VILLES DE LA R.D. CONGO
Kalenda Tshilombo, Nicodème ULg; Ciza Hamuli, Patient ULg; Mavungu Landu, Don Jethro ULg et al

Poster (2017, March)

Drug counterfeiting is a sad and worrisome reality, especially in developing countries where quality control is not effective and sometimes not existing at all despite political will of governments. The ... [more ▼]

Drug counterfeiting is a sad and worrisome reality, especially in developing countries where quality control is not effective and sometimes not existing at all despite political will of governments. The consequences are harmful in particular for substandard medicines that pose more threats to populations in those countries due to their direct negative impact on patients such as failure of medical treatment including development of drug resistance and even death. Socio-economic consequences and negative reputation concerning the pharmaceutical industry are also observed. Unfortunately accurate detailed data on such medicines are not easy to obtain. Most of the time available data are often estimated from case reports or studies carried out in a specific area and during a defined period.Health authorities’ in the Democratic Republic of Congo are trying to identify this scourge by set up several strategies to fight against. One of them is built on the best knowledge of drugs from several horizons through the assessment of their quality to allow appropriate measurement. In this context, we have focused our study towards amoxicillin alone and/or combined with potassium clavulanate since it is one the very used medicines in pediatric medications. The formulations are powder for suspension. Two analytical methods were developed based on the USP monography, applying isocratic liquid chromatography. Prior to their application in routine, we evaluated the suitability of these methods through validation applying the accuracy profile of total error. Since it was planned to transfer the methods to DRC, several operating factors were taken into account namely operator, day and equipment. Interesting results were obtained in terms of trueness (relative biases below than 2.3%), precision (RSD of Intermediate precision below 2.8%), accuracy (beta-expectation tolerance intervals between -6.0% and 3.8%) for the concentration levels of interest. The latter were able to allow monitoring the quality of the two active ingredients here above in the 65 samples from Congolese market. They were collected in Kinshasa, Lubumbashi, Matadi and Kolwezi at official and non-official medicines distributors, in peripheral area. The dramatic results obtained confirm that substandard and counterfeit medicines remain a crucial problem on public health in low-income countries. Appropriate measures are really needed to set up the drug quality improvement. [less ▲]

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See detailDynamiques mémorielles autour de la répression de la négation du génocide des Arméniens en Belgique et en France
Grandjean, Geoffrey ULg; Macq, Hadrien ULg

in Chabot, Joceline; Doucet, Marie-Michèle; Kasparian, Syvia (Eds.) et al Le génocide des Arméniens : représentations, traces, mémoires (2017)

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See detailCorde à Corde - Le duo Philippe AERTS ( contrebasse) - Raphaëlle BROCHET (chant) - interview
Sacré, Robert ULg

E-print/Working paper (2017)

Interview des 2 musiciens sur leur carrière et sur la sortie de l'album KALAMAMBA chez Igloo Records ( IGL282)

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See detailFactors controlling the evolution of groundwater dynamics and chemistry in the Senegal River Delta
Gning, Abdoul Aziz; Orban, Philippe ULg; Gesels, Julie ULg et al

in Journal of Hydrology: Regional Studies (2017), 10

tStudy region: Senegal River Delta. Study focus: The Senegal River Delta is a strategic region for the development of irri-gated agriculture. Despite a Sahelian climatic context, the management of the ... [more ▼]

tStudy region: Senegal River Delta. Study focus: The Senegal River Delta is a strategic region for the development of irri-gated agriculture. Despite a Sahelian climatic context, the management of the river withdams ensures water availability throughout the year. With the intensification of agri-culture, degradation of cultivated soils is observed, mostly linked to the existence of ashallow salty aquifer. In this context, regional surveys were performed to characterizegroundwater–surface water interactions and to identify the impact of artificial river man-agement and agricultural intensification on the evolution of groundwater dynamics andchemistry.New hydrological insights for the region: Results show that groundwater far away from riversand outside irrigated plots has evolved from marine water to brines under the influenceof evapotranspiration. Near rivers, salinity of groundwater is lower than seawater andgroundwater mineralization seems to evolve in the direction of softening through cationicexchanges related to permanent contact with fresh water. Despite large volumes of waterused for rice cultivation, groundwater does not show any real softening trend in the culti-vated parcels. Results show that the mechanisms that contribute to repel salt water fromthe sediments correspond to a lateral flush near permanent surface water streams and notto vertical drainage and dilution with rainfall or irrigation water. It is however difficultto estimate the time required to come back to more favorable conditions of groundwatersalinity. [less ▲]

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See detailCan science explain consciousness? Lessons from coma and related states
Martial, Charlotte ULg

Conference (2017, March)

Understanding consciousness remains one of the greatest mysteries for science to solve. How do our brains work? How can we know if some patients in coma have any consciousness left and how could we ... [more ▼]

Understanding consciousness remains one of the greatest mysteries for science to solve. How do our brains work? How can we know if some patients in coma have any consciousness left and how could we communicate with them? What are near-death experiences? What is brain death? What happens in our brains during dreaming, hypnosis or meditation? At present, nobody understands how matter (our trillions of neural connections) becomes perception and thought. We will here briefly review some neurological facts on consciousness and impaired consciousness. Thanks to recent advances in (neuroimaging) technology, the mapping of conscious perception and cognition in health (e.g., conscious waking, sleep, dreaming, hypnosis, meditation, sleepwalking and anesthesia) and in disease (e.g., coma, near-death, “vegetative” state, seizures, hallucinations etc) is providing exiting new insights into the functional neuroanatomy of human consciousness. Our perception of the outside world (sensory awareness; what we see, hear, etc.) and our awareness of an inner world (self-awareness; the little "voice" inside that "speaks" to ourselves) seemingly depend on two separate networks we could recently identify. Philosophers might argue that the subjective aspect of the mind will never be sufficiently accounted for by the objective methods of reductionistic science. We here prefer a more pragmatic approach and remain naively optimistic that technological advances might ultimately lead to an understanding of the neural substrate of human consciousness. [less ▲]

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See detailExpanding chemistry's horizon with continuous-flow reactors
Monbaliu, Jean-Christophe ULg

in Corning Reactor Technologies Annual Conference (2017) (2017, March)

Continuous-flow micro- and mesofluidic reactors come with inherent properties that can be advantageously utilized for expanding the horizon of synthetic organic chemistry. Accurate control over local ... [more ▼]

Continuous-flow micro- and mesofluidic reactors come with inherent properties that can be advantageously utilized for expanding the horizon of synthetic organic chemistry. Accurate control over local process parameters, even under extreme conditions, inherent safety, production homogeneity and seamless scale-up are amongst the most important assets of continuous-flow chemistry. Besides, flow chemistry enables the design of efficient multistep processes with significantly reduced footprints. In this lecture, we will discuss some of the most fascinating aspects of continuous-flow micro- and mesofluidic reactors in the specific context of preparative organic chemistry. Multiple examples illustrating the development and implementation of continuous-flow multistep strategies for the synthesis of high-value added organic targets will be presented. [less ▲]

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See detailQuel « PRP » pour traiter les tendinopathies chroniques ?
Kaux, Jean-François ULg; Emonds-Alt, Thibault ULg

in Journal de Traumatologie du Sport (2017), 34(1), 76-90

Plasma rich platelets (PRP) consist of blood plasma with a high concentration of platelets autologous constituting a huge reservoir of growthfactors. The clinical use of the PRP is widespread in various ... [more ▼]

Plasma rich platelets (PRP) consist of blood plasma with a high concentration of platelets autologous constituting a huge reservoir of growthfactors. The clinical use of the PRP is widespread in various medical applications. Even it is very popular with athletes, the use of PRP intendinopathies is still scientifically discussed, particularly related to a disparity in the products called PRP. In order to optimize employment, itshould be interested in the different stages of obtaining of the PRP. In this literature review, we analyzed in particular 8 parameters that can influencethe quality of the PRP: (1) anticoagulants used to preserve the best feature of platelet; (2) centrifuge speeds used in order to extract platelets; (3)platelet concentrations and the presence of leukocytes and erythrocytes in the PRP; (4) the platelet activators for the mast of platelets and thus therelease of growth factors; (5) use of local anesthetics to achieve infiltration, in addition to these parameters, it might be interesting to analyze othervariables like: (6) employment or not of buffer to neutralize the acidity caused by anticoagulants; (7) injection under US guidance or not; and (8)volume of PRP injected to determine their influence on the healing potential. [less ▲]

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See detailBetween practices and belongings: intersectional stories of migrant women around food
Mescoli, Elsa ULg

Conference (2017, March)

Short abstract Based on ethnographic fieldwork conducted among Moroccan women living in Milan hinterland in Italy, this paper aims at exploring the negotiated ways of performing both cultural and social ... [more ▼]

Short abstract Based on ethnographic fieldwork conducted among Moroccan women living in Milan hinterland in Italy, this paper aims at exploring the negotiated ways of performing both cultural and social belongings through food and at pointing out how these two dimensions can diverge or overlap in practice. Long abstract Migration constitutes for human beings an opportunity – among others – to develop a reflexive gaze upon one’s own habits (Rodier 2010), food habits in the case under study. In fact, not only changes that may occur in the ways of eating, cooking and supplying of produces, but also new relationships push individuals to question their everyday practices, which are associated with specific meanings. These meanings are socially and culturally oriented and performative, since they permit to state belongings as well as to take part to differently defined groups. In order to study these dynamics, I will present some ethnographic data collected during a research among Moroccan women living in Milan hinterland in Italy, mainly focusing on the history of two of them. The description of food practices, embedded in the narration of the migration experience and its consequences, which in its turn interacts with contextual discourses around immigrants and cultural diversity, reveals unexpected strategies to take social and cultural positionings within the collectivity. The theoretical framework upon which my analysis relies consists of a praxeological approach to subjectivation (Warnier 2001) combined with the consideration of the multi-dimensionality of the self which is derived from the intersectional perspective on identity (Crenshaw 1989; Anthias 2002; Yuval-Davis 2006). Through concrete practices involving food, individuals – women in this case – define their self as a layered complex of belongings, and they do that at both social and cultural level; thus proving how these two dimensions can diverge or overlap. [less ▲]

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See detailLundis en coulisse
Delhalle, Nancy ULg

Diverse speeche and writing (2017)

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See detailStructure impact of two galactomannan fractions on their viscosity properties in dilute solution, unperturbed state and gel state
Gillet, Sébastien; Aguedo, Mario ULg; Petrut, Raoul et al

in International Journal of Biological Macromolecules (2017), 96

Detailed reference viewed: 48 (12 ULg)