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See detailAre agricultural ecosystems important BVOC « exchangers »? Evidences from 2 measurement years on croplands at Lonzée (Belgium)
Bachy, Aurélie ULg; Aubinet, Marc ULg; Schoon, Niels et al

Poster (2014, July 01)

For the last decades, agricultural ecosystems have been a key biome for diverse socio-economical, environmental and climatic issues. And one of these climatic issues is just BVOC (Biogenic Volatile ... [more ▼]

For the last decades, agricultural ecosystems have been a key biome for diverse socio-economical, environmental and climatic issues. And one of these climatic issues is just BVOC (Biogenic Volatile Organic Compounds) emission from terrestrial ecosystems. Indeed, those compounds which are mostly emitted by plants play a great role in the atmospheric chemistry, thereby influencing the Earth surface radiative budget and the tropospheric air quality. However, so far, very few is known about BVOC exchange by crops, implying that huge uncertainties remain about qualifying, quantifying and determining sources/sinks and driving mechanisms of BVOC exchanges between croplands ecosystems and the atmosphere. We present here the first long term BVOC fluxes measurement study conducted on maize (2012) and winter wheat (2013), respectively the second and first most important worldwide crops (FAOSTAT). BVOC exchange was measured using the disjunct by mass scanning eddy covariance technique (+ PTR-MS, Ionicon) at the Lonzée Terrestrial Observatory (ICOS site) in Belgium. Main results are: (i) crops emit mainly methanol; (ii) BVOC fluxes from studied crops is lower than in literature, suggesting that agricultural ecosystems are poor BVOC exchangers; (iii) soil is a significant BVOC source. [less ▲]

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See detailX-ray emission from magnetic massive stars
Nazé, Yaël ULg; Petit, V.; Rindbrand, M. et al

Poster (2014, July 01)

Magnetically confined winds of early-type stars are expected to be sources of bright and hard X-rays. In an attempt to clarify the systematics of the observed X-ray properties, we have analyzed a large ... [more ▼]

Magnetically confined winds of early-type stars are expected to be sources of bright and hard X-rays. In an attempt to clarify the systematics of the observed X-ray properties, we have analyzed a large series of Chandra and XMM observations, corresponding to over 100 exposures of 60% of the known magnetic massive stars listed recently by Petit et al. (2013). We notably show that the X-ray luminosity is strongly correlated with mass-loss rate, in agreement with predictions of magnetically confined wind models. We also investigated the behavior of other X-ray properties (plasma temperature, absorption, variability), yielding additional constraints on models. This work not only advances our knowledge of the X-ray emission of massive stars, but also suggests new observational and theoretical avenues to further explore magnetically confined winds. [less ▲]

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See detailThe X-ray bright massive stars in Cyg OB2
Nazé, Yaël ULg; Cazorla, Constantin ULg; Rauw, Grégor ULg

Poster (2014, July 01)

As a complement to the results from the Cyg OB2 Chandra Legacy program, we present in this contribution the detailed analysis of the four X-ray bright massive stars dominating the cluster. Cyg OB2 #5, #8A ... [more ▼]

As a complement to the results from the Cyg OB2 Chandra Legacy program, we present in this contribution the detailed analysis of the four X-ray bright massive stars dominating the cluster. Cyg OB2 #5, #8A, and #9 are binary or multiple massive stars in the Cyg OB2 association displaying several peculiarities, such as bright X-ray emission and non-thermal radio emission. Our X-ray monitoring of these stars reveals the details of their behavior at high energies, which can be directly linked to wind-wind collisions (WWCs). In addition, the X-ray emission of Cyg OB2 #12, an evolved massive star, shows a long-term decrease, which could hint at the presence of a companion (with associated colliding winds) or indicate the return to quiescence of the system following a recent eruption. [less ▲]

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See detailContrôle de qualité des USP via segments attachés : recommandations de la SFGM-TC
De Vos, John; Birebent, B; Faucher, Catherine et al

in Pathologie et Biologie (2014)

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See detailModalités de conservation et de destruction des produits cellulaires cryopréservés : recommandations de la SFGM-TC
CALMELS, ; Boulanger, F; BAUDOUX, Etienne ULg et al

in Pathologie et Biologie (2014), 62(3),

Thousands of autologous and at less extent allogeneic hematopoietic stem cells (HSC) bags are cryopreserved in France. The majority of autologous HSC grafts are used within a year after collection ... [more ▼]

Thousands of autologous and at less extent allogeneic hematopoietic stem cells (HSC) bags are cryopreserved in France. The majority of autologous HSC grafts are used within a year after collection. However, many bags are still unused and cryopreserved for many years. In France and on a European scale, the ever-growing number of cryopreserved bags represents a real economic health concern. Indeed, the cost of storage is about 100 € per bag and per year. In addition, quality and therapeutic value of these long-term cryopreserved grafts needs to be evaluated. In the attempt to harmonize clinical practices between different French transplantation centers, the French Society of Bone Marrow Transplantation and Cell Therapies (SFGM-TC) set up its fourth annual series of workshops which brought together practitioners from its member centers across France. These workshops took place in September 2013 in Lille. In this article, we addressed the issue of the destruction of long-term cryopreserved grafts be them autologous or allogeneic and provide recommendations regarding their destruction. [less ▲]

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See detailColour-magnitude diagrams of transiting Exoplanets - II. A larger sample from photometric distances
Triaud, Amaury H. M. J.; Lanotte, Audrey ULg; Smalley, Barry et al

in Monthly Notices of the Royal Astronomical Society (2014), 444(1), 711-728

CColour-magnitude diagrams form a traditional way of presenting luminous objects in the Universe and compare them to each other. Here, we estimate the photometric distance of 44 transiting exoplanetary ... [more ▼]

CColour-magnitude diagrams form a traditional way of presenting luminous objects in the Universe and compare them to each other. Here, we estimate the photometric distance of 44 transiting exoplanetary systems. Parallaxes for seven systems confirm our methodology. Combining those measurements with fluxes obtained while planets were occulted by their host stars, we compose colour-magnitude diagrams in the near and mid-infrared. When possible, planets are plotted alongside very low mass stars and field brown dwarfs, who often share similar sizes and equilibrium temperatures. They offer a natural, empirical, comparison sample. We also include directly imaged exoplanets and the expected loci of pure blackbodies. Irradiated planets do not match blackbodies; their emission spectra are not featureless. For a given luminosity, hot Jupiters' daysides show a larger variety in colour than brown dwarfs do and display an increasing diversity in colour with decreasing intrinsic luminosity. The presence of an extra absorbent within the 4.5 μm band would reconcile outlying hot Jupiters with ultra-cool dwarfs' atmospheres. Measuring the emission of gas giants cooler than 1000 K would disentangle whether planets' atmospheres behave more similarly to brown dwarfs' atmospheres than to blackbodies, whether they are akin to the young directly imaged planets, or if irradiated gas giants form their own sequence. [less ▲]

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See detailSpatiotemporal distribution of last 500 yrs turbidites in the Western Gulf of Corinth, Greece: implications for the characterization of historical earthquakes
Beckers, Arnaud ULg; Hubert, Aurelia ULg; Beck, Christian et al

Poster (2014, July 01)

The Corinth rift is one of the fastest spreading rifts on Earth. 10 earthquakes of magnitude greater than 6 occurred during the last century. The question of seismic hazard is consequently particularly ... [more ▼]

The Corinth rift is one of the fastest spreading rifts on Earth. 10 earthquakes of magnitude greater than 6 occurred during the last century. The question of seismic hazard is consequently particularly relevant. Despite a long earthquake catalogue, estimations of earthquake hazard remain problematic because of the difficulty to associate each historical event to one of the many active faults mapped in the area. Consequently, combining seismology, history and paleoseismology in an interdisciplinary approach is here necessary and is the goal of the ANR-SISCOR project. In this framework, we investigated the offshore sediments in order to (1) better constraint the length of the active offshore faults, and (2) look for sedimentary signature of historical earthquakes. 600 km of high resolution seismic reflexion data have been acquired during two surveys and 12 short gravity cores have been retrieved. The latters are 0.5 to 1 m long, allowing us to analyze about 500 yrs of sedimentation. Two new faults potentially able to trigger M>5.5 earthquakes have been mapped in the northern part of the gulf based on seismic data. Sedimentary events (turbidites sensu lato) have been identified in some cores, essentially in the deep basin and in a 180m-deep sub-basin close to the northern coast. The comparison with the critically reviewed historical records shows that some of these events could have been triggered by historical earthquakes. The link between these potential earthquakes sedimentary signatures, historical events and active faults is discussed based on intensity maps and our new active fault map. [less ▲]

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See detailInvestigation of the stellar content in the western part of the Carina nebula
Kumar, Brajesh; Sharma, Saurabh; Manfroid, Jean ULg et al

in Astronomy and Astrophysics (2014), 567

Context. The low obscuration and proximity of the Carina nebula make it an ideal place to study the ongoing star formation process and impact of massive stars on low-mass stars in their surroundings. <BR ... [more ▼]

Context. The low obscuration and proximity of the Carina nebula make it an ideal place to study the ongoing star formation process and impact of massive stars on low-mass stars in their surroundings. <BR /> Aims: To investigate this process, we generated a new catalog of the pre-main-sequence stars in the Carina west (CrW) region and studied their nature and spatial distribution. We also determined various parameters (reddening, reddening law, age, mass), which are used further to estimate the initial mass function and K-band luminosity function for the region under study. <BR /> Methods: We obtained deep UBVRI Hα photometric data of the field situated to the west of the main Carina nebula and centered on WR 22. Medium-resolution optical spectroscopy of a subsample of X-ray selected objects along with archival data sets from Chandra, XMM-Newton and 2MASS surveys were used for the present study. Different sets of color-color and color-magnitude diagrams are used to determine reddening for the region and to identify young stellar objects (YSOs) and estimate their age and mass. <BR /> Results: Our spectroscopic results indicate that the majority of the X-ray sources are late spectral type stars. The region shows a large amount of differential reddening with minimum and maximum values of E(B - V) as 0.25 and 1.1 mag, respectively. Our analysis reveals that the total-to-selective absorption ratio R[SUB]V[/SUB] is ~3.7 ± 0.1, suggesting an abnormal grain size in the observed region. We identified 467 YSOs and studied their characteristics. The ages and masses of the 241 optically identified YSOs range from ~0.1 to 10 Myr and ~0.3 to 4.8 M[SUB]⊙[/SUB], respectively. However, the majority of them are younger than 1 Myr and have masses below 2 M[SUB]⊙[/SUB]. The high mass star WR 22 does not seem to have contributed to the formation of YSOs in the CrW region. The initial mass function slope, Γ, in this region is found to be -1.13 ± 0.20 in the mass range of 0.5 < M/M[SUB]⊙[/SUB] < 4.8. The K-band luminosity function slope (α) is also estimated as 0.31 ± 0.01. We also performed minimum spanning tree analysis of the YSOs in this region, which reveals that there are at least ten YSO cores associated with the molecular cloud, and that leads to an average core radius of 0.43 pc and a median branch length of 0.28 pc. Full Table 3 is only available at the CDS via anonymous ftp to <A href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A> (ftp://130.79.128.5) or via <A href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/567/A109">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/567/A109</A> [less ▲]

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See detailConstraints on the summer-to-winter transport from SPICAM/MEX nitric oxide observations
Stiepen, Arnaud ULg; Gérard, Jean-Claude ULg; Gagné, M.-E. et al

Conference (2014, July 01)

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See detailDiurnal thermosphere scale height from MEX/SPICAM grazing limb data
Stiepen, Arnaud ULg; Gérard, Jean-Claude ULg; Bougher, S et al

Conference (2014, July 01)

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See detailLa langue qui goûte. Manger marocain(s) en Italie.
Mescoli, Elsa ULg

Article for general public (2014)

Fatéma Hal, ethnologue et restauratrice marocaine, décrit la nourriture, ainsi que la parole, comme ultime possession dont on ne peut jamais se défaire. On est ce qu’on mange, où qu’on soit. Mais on peut ... [more ▼]

Fatéma Hal, ethnologue et restauratrice marocaine, décrit la nourriture, ainsi que la parole, comme ultime possession dont on ne peut jamais se défaire. On est ce qu’on mange, où qu’on soit. Mais on peut pousser l’analyse au-delà de cela, en affirmant que c’est encore à travers le goût qu’on connait l’autre. Qu’il s’agisse d’ « exotisme culinaire » (Régnier 2004) ou de ce que l’on pourrait définir comme un « cannibalisme exogène », la dégustation des cuisines ainsi dites « ethniques » est une pratique à la mode. Manger l’Autre, pour le connaître ou pour le contrôler ; se faire manger par l’Autre, pour raconter de soi ou pour satisfaire les discours sur l’intégration, témoignent du rôle complexe de la nourriture dans les rapports humains à travers les cultures. L’étude ethnographique que je présente dans cet article vise à illustrer comment certaines femmes marocaines vivant en Italie construisent un savoir culinaire commun, fait de pratiques et de saveurs mobiles, et de quelle façon ce même savoir est acteur du domaine publique. [less ▲]

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See detailFormal and semantic-discursive properties of mirative exprecctions (it's) no wonder: a synchronic-diachronic approach
Gentens, Caroline; Brems, Lieselotte ULg; Davidse, Kristin et al

Conference (2014, July)

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See detailMetacognition and school learning: Individual use of the DELV program with teenagers
Frenkel, Stéphanie ULg; Nobile, Debora ULg

Conference (2014, July)

In the framework of self-regulated learning theories, the DELV (“Understanding one’s own learning”) is a 165-page metacognitive intervention program developed by Büchel & Büchel (1995, 1997, 2009, 2010 ... [more ▼]

In the framework of self-regulated learning theories, the DELV (“Understanding one’s own learning”) is a 165-page metacognitive intervention program developed by Büchel & Büchel (1995, 1997, 2009, 2010, 2011). It includes 8 types of decontextualized exercises which notably allow to develop the learner’s metacognitive knowledge and skills (for more details, see Büchel, 2013b). They also make it possible to work on cognitive and psycho-affective aspects. Transfer can thus be better developed. This tool has been used since its first version (Büchel & Büchel, 1995) both at the Atelier d’Apprentissage of the University of Genève (Unige, Switzerland) and at that of the University of Liège (ULg, Belgium) since their creation (respectively in 1996 and in 2009), (for more details, see Büchel, 2013a; Frenkel, in press (b)). Our main purpose is to present how we can use this tool individually in order to enable the student to activate his/her “sleeping potential” (for more details, see Frenkel, in press (a)). By focusing on adolescence, we will present (a) our theoretical background (conception of learning and intellectual functioning, criteria and levels of mediation), (b) the variables worked on, and (c) the results obtained. Note: Part of the Psychological and Speech therapy consultation Centre (CPLU, ULg), Belgium’s Atelier d’Apprentissage [Learning Workshop] intended for children and teenagers with temporary school learning difficulties. See www.cplu.ulg.ac.be References - Büchel, F.P. (2013a). L’intervention psychopédagogique auprès des enfants ayant des difficultés d’apprentissage. Un modèle métacognitif et d’autorégulation. In J.-L. Berger & F.P. Büchel (Eds.), L’autorégulation de l’apprentissage: Perspectives théoriques et applications (pp. 71- 105). Nice, France: Les Editions Ovadia. - Büchel, F.P. (2013b). Le programme DELV – Comprendre son propre apprentissage. Evaluation scientifique auprès d’enfants et d’adolescents sans ou avec difficultés d’apprentissage. In J.-L. Berger & F.P. Büchel (Eds.), L’autorégulation de l’apprentissage: Perspectives théoriques et applications (pp. 293-336). Nice, France: Les Editions Ovadia. - Büchel, F.P. & Büchel, P. (1995). Découvrez vos capacités, rEalisez vos possibilités, pLanifiez votre démarche, soyez créatiFs. Le programme DELF. Russin, Switzerland: Centre d’éducation cognitive. - Büchel, F.P., & Büchel, P. (1997). DELV. Das Eigene Lernen Verstehen. Ein Programm zur Förderung des Lernens und Denkens für Jugendliche und Erwachsene. Aarau, Switzerland: Sauerländer. - Büchel, F.P. & Büchel, P. (2010). DELV. Das Eigene Lernen Verstehen. Ein Programm zur Förderung des Lernens für Jugendliche und Erwachsene (4. überarbeitete Auflage). Berne, Switzerland: h.e.p. Verlag. - Büchel, F.P. & Büchel, P. (2011). DELV. Comprendre son propre apprentissage. Tegna, Suisse: Centre d’éducation cognitive. - Frenkel, S. (in press (a)). Metacognitive components in learning to learn approaches. International Journal of Psychology: A Biopsychosocial Approach. - Frenkel, S. (in press (b)). Métacognition et réussite scolaire : Applications. In C. Giraudeau & G. Chasseigne (Eds.), Psychologie, Education et Vie scolaire. Tours, France: Editions Publibook Université. - Frenkel, S., & Deforge, H. (in press). Métacognition et réussite scolaire: Perspectives théoriques. In C. Giraudeau & G. Chasseigne (Eds.), Psychologie, Education et Vie scolaire. Tours, France: Editions Publibook Université. [less ▲]

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See detailMetacognition and school learning: Use of the DELV program in primary school
Nobile, Debora ULg; Frenkel, Stéphanie ULg

Poster (2014, July)

In the framework of self-regulated learning theories, the DELV (“Understanding one’s own learning”) is a 165-page metacognitive intervention program developed by Büchel & Büchel (1995, 1997, 2009, 2010 ... [more ▼]

In the framework of self-regulated learning theories, the DELV (“Understanding one’s own learning”) is a 165-page metacognitive intervention program developed by Büchel & Büchel (1995, 1997, 2009, 2010, 2011). It includes 8 types of decontextualized exercises which notably allow to develop the learner’s metacognitive knowledge and skills (for more details, see Büchel, 2013). They also make it possible to work on cognitive and psycho-affective aspects. Transfer can thus be better developed. This tool is really useful (for more details, see Berger & Büchel, 2013) and, in our opinion, still not sufficiently known. Our main purpose is to present (a) its objectives, (b) the variables worked on (cognitive, metacognitive and psycho-affective), (c) possible uses in a school context within classes (e.g., the “sandwich method”) and (d) the outcome we can expect. References - Berger, J.-L., & Büchel, F.P. (2013), L’autorégulation de l’apprentissage: Perspectives théoriques et applications. Nice, France: Les Editions Ovadia. - - Büchel, F.P. (2013). Le programme DELV – Comprendre son propre apprentissage. Evaluation scientifique auprès d’enfants et d’adolescents sans ou avec difficultés d’apprentissage. In J.-L. Berger & F.P. Büchel (Eds.), L’autorégulation de l’apprentissage: Perspectives théoriques et applications (pp. 293-336). Nice, France: Les Editions Ovadia. - Büchel, F.P. & Büchel, P. (1995). Découvrez vos capacités, rEalisez vos possibilités, pLanifiez votre démarche, soyez créatiFs. Le programme DELF. Russin, Switzerland: Centre d’éducation cognitive. - Büchel, F.P., & Büchel, P. (1997). DELV. Das Eigene Lernen Verstehen. Ein Programm zur Förderung des Lernens und Denkens für Jugendliche und Erwachsene. Aarau, Switzerland: Sauerländer. - Büchel, F.P. & Büchel, P. (2009). DELV. Das Eigene Lernen Verstehen. Ein Programm zur Förderung des Lernens für Jugendliche und Erwachsene (3. vollständig überarbeitete Auflage). Berne, Switzerland: h.e.p. Verlag. - Büchel, F.P. & Büchel, P. (2010). DELV. Das Eigene Lernen Verstehen. Ein Programm zur Förderung des Lernens für Jugendliche und Erwachsene (4. überarbeitete Auflage). Berne, Switzerland: h.e.p. Verlag. - Büchel, F.P. & Büchel, P. (2011). DELV. Comprendre son propre apprentissage. Tegna, Switzerland: Centre d’éducation cognitive. [less ▲]

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See detailLink between learning profile and school achievement in primary school; a transversal study
Frenkel, Stéphanie ULg; Nobile, Debora ULg

Conference (2014, July)

School achievement plays an essential role in terms of professional and social adaptation. However, all the students do not always perform as the system requires them to. In Belgium, at the end of ... [more ▼]

School achievement plays an essential role in terms of professional and social adaptation. However, all the students do not always perform as the system requires them to. In Belgium, at the end of compulsory education, one student out of two lags behind in their school education (Indicators from the Fédération Wallonie-Bruxelles [Walloon-Brussels Federation], 2012). In this context, we do not consider that there are “bad” learners. Instead, there are those students whose learning profile is more or less in line with the context’s requirements and those whose profile is not. In many works, the student’s learning profile is operationalised by measures on 3 levels: cognitive, metacognitive and psycho-affective. These psychological variables, which are major components of self-regulated learning, play a central role in the explanation of school performance (for more details, see Frenkel, in press; Frenkel & Deforge, in press). This profile is not fixed once and for all. It evolves over time and it represents the result of the interaction between these three variables with other factors, notably bio-medical, socio-demographical ones, factors related to family environment (Pourtois, Desmet & Lahaye, 2004; Trudel, Puentes-Neuman & Ntebutse, 2002) and the too often forgotten factors linked to class management and social interactions between students and teachers (see Wang, Haertel & Walberg, 1994). Determining the students’ learning profile enables us to identify their strengths and work on their weaknesses. Therefore, it is essential that psycho-educational teams have validated tools at their disposal in order to carry out this task. Our aim is to propose new tools which will complement the already-existing ones. In this presentation we propose to introduce and discuss our methodology and the results obtained. The starting target population was made up of 198 primary school students divided equitably into three levels (second year of primary school, fourth year of primary school and sixth year of primary school). A problem-solving task based on the DELF (Büchel & Büchel, 1995) was created. It was completed by two questionnaires to fill in before and after the task. The learning profile defined on this basis was analysed according to several variables (age, gender, socio-professional category, school results). Group testing is still in progress. We will also illustrate our presentation with the first results of individual testing which will begin in May 2014. References - Büchel, F.P. & Büchel, P. (1995). Découvrez vos capacités, rEalisez vos possibilités, pLanifiez votre démarche, soyez créatiFs. Le programme DELF. Russin, Switzerland: Centre d’éducation cognitive - Frenkel, S. (in press). Metacognitive components in learning to learn approaches. International Journal of Psychology: A Biopsychosocial Approach - Frenkel, S., & Deforge, H. (in press). Métacognition et réussite scolaire: Perspectives théoriques. In C. Giraudeau & G. Chasseigne (Eds.), Psychologie, Education et Vie scolaire. Tours, France: Editions Publibook Université - Pourtois, J.-P., Desmet, H., & Lahaye, W. (2004). Connaissances et pratiques en éducation familiale et parentale. Enfances, Familles, Générations, 1, 22-35 - Trudel, M., Puentes-Neuman, G., & Ntebutse J.G. (2002). Les conceptions contemporaines de l’enfant à risque et la valeur heuristique du construit de résilience en éducation. Revue Canadienne de l’Education, 27 (2 & 3), 153-173 - Wang, M.C., Haertel, G.D., & Walberg, H.J. (1994). What helps students learn? Educational Leadership, 51 (4), 74-79 [less ▲]

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See detailHD 97658 and its super-Earth. Spitzer & MOST transit analysis and modeling of the host star
Van Grootel, Valérie ULg; Gillon, Michaël ULg; Valencia, D. et al

Conference (2014, July)

Super-Earths transiting nearby bright stars are key objects that simultaneously allow for accurate measurements of both their mass and radius, providing essential constraints on their internal composition ... [more ▼]

Super-Earths transiting nearby bright stars are key objects that simultaneously allow for accurate measurements of both their mass and radius, providing essential constraints on their internal composition. We present here the confirmation, based on Spitzer transit observations, that the super-Earth HD 97658 b transits its host star. HD 97658 is a low-mass ($M_*=0.77\pm0.05\,M_{\odot}$) K1 dwarf, as determined from the Hipparcos parallax and stellar evolution modeling. To constrain the planet parameters, we carry out Bayesian global analyses of Keck-HIRES radial velocities, and MOST and Spitzer photometry. HD 97658 b is a massive ($M_P=7.55^{+0.83}_{-0.79} M_{\oplus}$) and large ($R_{P} = 2.247^{+0.098}_{-0.095} R_{\oplus}$ at 4.5 $\mu$m) super-Earth. We investigate the possible internal compositions for HD 97658 b. Our results indicate a large rocky component, by at least 60% by mass, and very little H-He components, at most 2% by mass. We also discuss how future asteroseismic observations can improve the knowledge of the HD 97658 system, in particular by constraining its age. Orbiting a bright host star, HD 97658 b will be a key target for coming space missions TESS, CHEOPS, PLATO, and also JWST, to characterize thoroughly its structure and atmosphere. [less ▲]

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See detailEconomic Statistical Design of the VP( X) ̅ Control Charts for Monitoring a Process under Non-normality
Seif, Asghar; Faraz, Alireza ULg; Saniga, Erwin

E-print/Working paper (2014)

Recent studies proved that variable parameters (VP) X ̅ control charts not only detects process mean shifts quicker than the classical X ̅ control chart but also has better economic properties ... [more ▼]

Recent studies proved that variable parameters (VP) X ̅ control charts not only detects process mean shifts quicker than the classical X ̅ control chart but also has better economic properties. Furthermore, like most papers in control chart design, the fundamental assumption is that process data are normally distributed. Nevertheless, process quality variables may not be normal in application. In this paper, we investigate the economic statistical design of the VP X ̅ control chart when the underlying process distribution is non-normal. We illustrate the design procedure and perform a sensitivity analysis on the process and cost parameters based upon the degrees of skewness and kurtosis of the population using an industrial application. [less ▲]

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See detailMagnetic characterisation of large grain, bulk Y–Ba–Cu–O superconductor–soft ferromagnetic alloy hybrid structures
Philippe, Matthieu ULg; Fagnard, Jean-François ULg; Kirsch, Sébastien ULg et al

in Physica C: Superconductivity (2014), 502

Large grain, bulk Y–Ba–Cu–O (YBCO) high temperature superconductors (HTS) have significant potential for use in a variety of practical applications that incorporate powerful quasi-permanent magnets. In ... [more ▼]

Large grain, bulk Y–Ba–Cu–O (YBCO) high temperature superconductors (HTS) have significant potential for use in a variety of practical applications that incorporate powerful quasi-permanent magnets. In the present work, we investigate how the trapped field of such magnets can be improved by combining bulk YBCO with a soft FeNi, ferromagnetic alloy. This involves machining the alloy into components of various shapes, such as cylinders and rings, which are attached subsequently to the top surface of a solid, bulk HTS cylinder. The effect of these modifications on the magnetic hysteresis curve and trapped field of the bulk superconductor at 77 K are then studied using pick-up coil and Hall probe measurements. The experimental data are compared to finite element modelling of the magnetic flux distribution using Campbell’s algorithm. Initially we establish the validity of the technique involving pick-up coils wrapped around the bulk superconductor to obtain its magnetic hysteresis curve in a non-destructive way and highlight the difference between the measured signal and the true magnetization of the sample. We then consider the properties of hybrid ferromagnet/superconductor (F/S) structures. Hall probe measurements, together with the results of the model, establish that flux lines curve outwards through the ferromagnet, which acts, effectively, like a magnetic short circuit. Magnetic hysteresis curves show that the effects of the superconductor and the ferromagnet simply add when the ferromagnet is saturated fully by the applied field. The trapped field of the hybrid structure is always larger than that of the superconductor alone below this saturation level, and especially when the applied field is removed. The results of the study show further that the beneficial effects on the trapped field are enhanced when the ferromagnet covers the entire surface of the superconductor for different ferromagnetic components of various shapes and fixed volume. [less ▲]

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