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See detailDistributed learning: Developing a predictive model based on data from multiple hospitals without data leaving the hospital – A real life proof of concept
JOCHEMS, Arthur; DEIST, Timo M.; VAN SOEST, Johan et al

in Radiotherapy & Oncology (2016)

Purpose: One of the major hurdles in enabling personalized medicine is obtaining sufficient patient data to feed into predictive models. Combining data originating from multiple hospitals is difficult ... [more ▼]

Purpose: One of the major hurdles in enabling personalized medicine is obtaining sufficient patient data to feed into predictive models. Combining data originating from multiple hospitals is difficult because of ethical, legal, political, and administrative barriers associated with data sharing. In order to avoid these issues, a distributed learning approach can be used. Distributed learning is defined as learning from data without the data leaving the hospital. Patients and methods:Clinical data from 287 lung cancer patients, treated with curative intent with chemoradiation (CRT) or radiotherapy (RT) alone were collected from and stored in 5 different medical institutes (123 patients at MAASTRO (Netherlands, Dutch), 24 at Jessa (Belgium, Dutch), 34 at Liege (Belgium, Dutch and French), 48 at Aachen (Germany, German) and 58 at Eindhoven (Netherlands, Dutch)). A Bayesian network model is adapted for distributed learning (watch the animation: http://youtu.be/nQpqMIuHyOk). The model predicts dyspnea, which is a common side effect after radiotherapy treatment of lung cancer. Results:We show that it is possible to use the distributed learning approach to train a Bayesian network model on patient data originating from multiple hospitals without these data leaving the individual hospital. The AUC of the model is 0.61 (95%CI, 0.51–0.70) on a 5-fold cross-validation and ranges from 0.59 to 0.71 on external validation sets. Conclusion: Distributed learning can allow the learning of predictive models on data originating from multiple hospitals while avoiding many of the data sharing barriers. Furthermore, the distributed learning approach can be used to extract and employ knowledge from routine patient data from multiple hospitals while being compliant to the various national and European privacy laws. [less ▲]

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See detailThe functional-biogeography of the reef fishes in the Gulf of California: over-importance of a handful of sites
Olivier, Damien ULg; Reyes Bonilla, Hector

Poster (2016, October 03)

Functional biogeography is a new discipline allowing to link biogeographical patterns of trait and species diversity. This new area of research has a role in conservation policy because it permits to ... [more ▼]

Functional biogeography is a new discipline allowing to link biogeographical patterns of trait and species diversity. This new area of research has a role in conservation policy because it permits to create functional maps to highlight hotspots of biodiversity. In this study, we evaluate the taxonomic and functional diversity of the reef-fishes in 30 “archipelagoes” widespread along the Gulf of California (GOC). The question before us is to highlight areas requiring a particular intention in conservation policy because they represent a large part of the legacy of reef-fish diversity in the GOC. To do so, we used a recently developed method to classify the reef-fishes species of the GOC in functional entities (FEs). The FEs are based on unique combinations of six categorical traits known to influence the functional role of fishes (e.g. size, diet…) and their number represent the level of functional diversity of the community. The results showed that the Baja California Sur has the most diversified reef-fishes community, both taxonomically and functionally (more than 90% of the species and of the functional diversity are represented). This result is mainly due to four archipelagoes that present a dazzling diversity, i.e. Carmen, San José, Espiritu Santo and Cerralvo. Each of these islands includes 60% or more of the taxonomic and functional diversity of the GOC. Two of these archipelagoes benefit of a protection level through the National Parks of Loreto and Espiritu Santo. However, the former is poorly functioning and the latter is under evaluation. The outcomes of the present study provide a global map of the reef-fishes diversity through the GOC, in term of species number and functional diversity. These results allow the identification of four major hotspots of diversity that should require a particular attention to preserve the legacy of reef-fishes diversity in the GOC. [less ▲]

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See detailChaises mobiles, murs qui deviennent des tableaux...: les auditoires sont à repenser
Verpoorten, Dominique ULg

Article for general public (2016)

A l’heure où le numérique s’affirme comme une préoccupation majeur pour l’enseignement supérieur, la réflexion sur les nouveaux espaces physiques d’apprentissage représente un autre défi.

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See detailTowards a new vision on power relations inside fieldwork: Like Haraway's Mutated Witness
Vivas Romero, Maria ULg

Scientific conference (2016, October 03)

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See detailDe la carte à la géovisualisation 3D
Billen, Roland ULg

Conference given outside the academic context (2016)

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See detailA Stochastic Multi-Scale Approach for the Modeling of Thermo-Elastic Damping in Micro-Resonators
Wu, Ling ULg; Lucas, Vincent ULg; Nguyen, Van Dung ULg et al

in Computer Methods in Applied Mechanics & Engineering (2016), 310

The aim of this work is to study the thermo-elastic quality factor (Q) of micro-resonators with a stochastic multi-scale approach. In the design of high-Q micro-resonators, thermo-elastic damping is one ... [more ▼]

The aim of this work is to study the thermo-elastic quality factor (Q) of micro-resonators with a stochastic multi-scale approach. In the design of high-Q micro-resonators, thermo-elastic damping is one of the major dissipation mechanisms, which may have detrimental effects on the quality factor, and has to be predicted accurately. Since material uncertainties are inherent to and unavoidable in micro-electromechanical systems (MEMS), the effects of those variations have to be considered in the modeling in order to ensure the required MEMS performance. To this end, a coupled thermo-mechanical stochastic multi-scale approach is developed in this paper. Thermo-mechanical micro-models of polycrystalline materials are used to represent micro-structure realizations. A computational homogenization procedure is then applied on these statistical volume elements to obtain the stochastic characterizations of the elasticity tensor, thermal expansion, and conductivity tensors at the meso-scale. Spatially correlated meso-scale random fields can thus be generated to represent the stochastic behavior of the homogenized material properties. Finally, the distribution of the thermo-elastic quality factor of MEMS resonators is studied through a stochastic finite element method using as input the generated stochastic random field. [less ▲]

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See detailFacteurs d’ambiance dans l’industrie textile en République Démocratique du Congo: état de lieu
Panda Lukongo, Kitronza ULg; Mairiaux, Philippe ULg

in Pan African Medical Journal (The) (2016), 25(44),

Introduction: This case study aims to make an assessment of environmental health nuisances in textile industry in the Democratic Republic of Congo. Methods: We conducted a cross-sectional and analytical ... [more ▼]

Introduction: This case study aims to make an assessment of environmental health nuisances in textile industry in the Democratic Republic of Congo. Methods: We conducted a cross-sectional and analytical study. Out of 257 workers selected using systematic sampling, 229 workers were enrolled in the study. 223 workstations were subjected to measurements in order to determine the level of noise, lighting and heat. Data were collected from company documents, by means of a direct-question interview focusing on socio professional informations and through measurements. Descriptive analysis was used for sociodemographic and professional data and analytical approach was used for themeasurements. Results: In the company studied 88% of employees were workers. Weaving department included almost 68% of workers. The majority of employees worked as part of a three shift (85%). The study population was predominantly male (85%), aging (52%) over 40 years and educated (80%). In the company studied, only 12.1% of workstations met the noise standards and 18% of workstations met the lighting standards. 94% of workstations didn't meet the heat standards for heavy work. Conclusion: Our study highlighted the environmental health nuisances in textile industry, demonstrating the existence of significant gaps related to the prescribed standards for the measured nuisances. These results are a plea for the development of appropriate preventive measures. They should be confronted with other more detailed studies in this work environment. [less ▲]

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See detailOPTIMIZATION OF A FULLY AUTOMATED ELECTROPHORETICALLY MEDIATED MICROANALYSIS SYSTEM FOR CYP1A1 ACTIVITY MONITORING
Farcas, Elena ULg; Servais, Anne-Catherine ULg; Lamalle, Caroline et al

Conference (2016, October 01)

Objective of the study Since CYP1A1, a member of cytochrome P450 superfamily, has been described to be over expressed in various types of cancer, our study was focused on the optimization of a fully ... [more ▼]

Objective of the study Since CYP1A1, a member of cytochrome P450 superfamily, has been described to be over expressed in various types of cancer, our study was focused on the optimization of a fully automated system for the monitoring of this particularly interesting enzyme. Moreover, the potentiality of this approach to screen CYP1A1 inhibitors was investigated. Materials and methods The experiments were carried out on a HP3DCE system using an on-column DAD. The EMMA procedure was performed by injecting a plug containing the co-factor(NADPH) and the substrate(7-ethoxycoumarin) between two plugs of CYP1A1 supersomes. The reaction was triggered by the application of a voltage switch. The voltage was then turned off to allow the metabolic reaction to occur. The separation of the components was then performed. Results Satisfying results were obtained using CYP1A1 at a concentration of 200 pmol/mL, while the incubation time was settled to 15 min. A DoE was performed to find the best mixing conditions. The amount of metabolite obtained was comparable to the one detected after conventional off-line metabolization. The ability of our system to monitor CYP1A1 inhibition was then proven with apigenin, a well-known CYP1A1 inhibitor. Conclusions The present study describes the development of a fully automatized in-capillary method for CYP1A1 activity monitoring and proves the potentialy of our system to be used for the screening of CYP1A1 inhibitors. The advantages of performing inline metabolization assays are mainly the miniaturization and the automatization of the process. Besides, the reagents consumption is drastically reduced due to the injection of few tens of nanoliters. [less ▲]

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See detailThe OD/OH Isotope Ratio in Comets 8P/Tuttle and C/2012 F6 (Lemmon)
Rousselot, Philippe; Jehin, Emmanuel ULg; Hutsemekers, Damien ULg et al

in Bulletin of the American Astronomical Society (2016, October 01), 48

The determination of isotopic ratios in solar system objects is an important source of information about their origin, especially for comets. Among these ratios the D/H is of particular importance because ... [more ▼]

The determination of isotopic ratios in solar system objects is an important source of information about their origin, especially for comets. Among these ratios the D/H is of particular importance because of its sensitivity to fractionation processes and physical environment, and the abundance of hydrogen in the solar system. The main molecule used to derive this ratio in comets is water. So far, apart water, only HCN has permitted to derive D/H ratio and not only upper limits.Most of the existing determinations of D/H in water molecules have been obtained by spectroscopic observations of water lines in the sub-mm or near infrared range [1,2]. So far only one measurement has been based on OD/OH emission lines radicals in the near-UV [3] and another one on the Lyman-alpha D emission [4]. In situ measurements have also been obtained in comets 1P/Halley and 67P/Churyumov-Gerasimenko using mass spectrometer [5,6,7,8].In this work we have used the OH and OD ultraviolet bands at 310 nm observed with the ESO 8-m Very Large Telescope feeding the Ultraviolet-Visual Echelle Spectrograph (UVES) for measuring the D/H ratio in comets 8P/Tuttle and C/2012 F6 (Lemmon). The OH and OD being the photodissociation products of H[SUB]2[/SUB]O and HDO such observations allow to derive D/H ratio for water molecules. This work constitutes an independant determination of the D/H ratios already published for these comets and based on observations performed in the sub-mm and near infrared range of H[SUB]2[/SUB]O and HDO lines. We present our modeling, data analysis and numerical values obtained for this ratio.[1] D. Bockelée-Morvan et al., 2015, SSR 197, 47-83 [2] N. Biver et al., 2016, A&A 589, id A78, 11p [3] D. Hutsemékers et al., 2008, A&A 490, L31 [4] H.A. Weaver et al., 2008, LPI Contributions 1405, 8216 [5] H. Balsiger, K. Altwegg, J. Geiss, 1995, JGR 100, 5827 [6] P. Eberhardt et al., 1995, A&A 302, 301 [7] R.H. Brown et al., 2012, PSS 60, 166 [8] K. Alwegg et al., 2015, Science 347, article id. 1261952 [less ▲]

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See detailSurvey for Ortho-to-Para Abundance Ratios (OPRs) of NH2 in Comets: Revisit to the Meaning of OPRs of Cometary Volatiles
Kawakita, Hideyo; Shinnaka, Yoshiharu; Jehin, Emmanuel ULg et al

in Bulletin of the American Astronomical Society (2016, October 01), 48

Since molecules having identical protons can be classified into nuclear-spin isomers (e.g., ortho-H[SUB]2[/SUB]O and para-H[SUB]2[/SUB]O for water) and their inter-conversions by radiative and non ... [more ▼]

Since molecules having identical protons can be classified into nuclear-spin isomers (e.g., ortho-H[SUB]2[/SUB]O and para-H[SUB]2[/SUB]O for water) and their inter-conversions by radiative and non-destructive collisional processes are believed to be very slow, the ortho-to-para abundance ratios (OPRs) of cometary volatiles such as H[SUB]2[/SUB]O, NH[SUB]3[/SUB] and CH[SUB]4[/SUB] in coma have been considered as primordial characters of cometary molecules [1]. Those ratios are usually interpreted as nuclear-spin temperatures although the real meaning of OPRs is in strong debate. Recent progress in laboratory studies about nuclear-spin conversion in gas- and solid-phases [2,3] revealed short-time nuclear-spin conversions for water, and we have to reconsider the interpretation for observed OPRs of cometary volatiles. We have already performed the survey for OPRs of NH[SUB]2[/SUB] in more than 20 comets by large aperture telescopes with high-resolution spectrographs (UVES/VLT, HDS/Subaru, etc.) in the optical wavelength region [4]. The observed OPRs of ammonia estimated from OPRs of NH[SUB]2[/SUB], cluster around ~1.1 (cf. 1.0 as a high-temperature limit), indicative of ~30 K as nuclear-spin temperatures. We present our latest results for OPRs of cometary NH[SUB]2[/SUB] and discuss about the real meaning of OPRs of cometary ammonia, in relation to OPRs of water in cometary coma. Chemical processes in the inner coma may play an important role to achieve un-equilibrated OPRs of cometary volatiles in coma.This work was financially supported by MEXT Supported Program for the Strategic Research Foundation at Private Universities, 2014–2018 (No. S1411028) (HK) and by Graint-in-Aid for JSPS Fellows, 15J10864 (YS).References:[1] Mumma & Charnley, 2011, Annu. Rev. Astro. Astrophys. 49, 471.[2] Hama & Watanabe, 2013, Chem. Rev. 113, 8783.[3] Hama et al., 2008, Science 351, 6268.[4] Shinnaka et al., 2011, ApJ 729, 81. [less ▲]

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See detailTracing back the evolution of the candidate LBV HD 168625
Mahy, Laurent ULg; Hutsemekers, Damien ULg; Royer, P. et al

in Astronomy and Astrophysics (2016), 594

Context. The luminous blue variable phase is a crucial transitory phase that is not clearly understood in the massive star evolution. <BR /> Aims: We have obtained far-infrared Herschel/PACS imaging and ... [more ▼]

Context. The luminous blue variable phase is a crucial transitory phase that is not clearly understood in the massive star evolution. <BR /> Aims: We have obtained far-infrared Herschel/PACS imaging and spectroscopic observations of the nebula surrounding the candidate LBV HD 168625. By combining these data with optical spectra of the central star, we want to constrain the abundances in the nebula and in the star and compare them to trace back the evolution of this object. <BR /> Methods: We use the CMFGEN atmosphere code to determine the fundamental parameters and the CNO abundances of the central star whilst the abundances of the nebula are derived from the emission lines present in the Herschel/PACS spectrum. <BR /> Results: The far-infrared images show a nebula composed of an elliptical ring/torus of ejecta with a ESE-WNW axis and of a second perpendicular bipolar structure composed of empty caps/rings. We detect equatorial shells composed of dust and ionized material with different sizes when observed at different wavelengths, and bipolar caps more of less separated from the central star in Hα and mid-IR images. This complex global structure seems to show two different inclinations: ~40° for the equatorial torus and ~ 60° for the bipolar ejections. From the Herschel/PACS spectrum, we determine nebular abundances of N/H = 4.1 ± 0.8 × 10[SUP]-4[/SUP] and , as well as a mass of ionized gas of 0.17 ± 0.04 M[SUB]⊙[/SUB] and a neutral hydrogen mass of about 1.0 ± 0.3 M[SUB]⊙[/SUB] which dominates. Analysis of the central star reveals T[SUB]eff[/SUB] = 14 000 ± 2000 K, log g = 1.74 ± 0.05 and log (L/L[SUB]⊙[/SUB]) = 5.58 ± 0.11. We derive stellar CNO abundances of about N/H = 5.0 ± 1.5 × 10[SUP]-4[/SUP], C/H = 1.4 ± 0.5 × 10[SUP]-4[/SUP] and O/H = 3.5 ± 1.0 × 10[SUP]-4[/SUP], not significantly different from nebular abundances. All these measurements taken together are compatible with the evolutionary tracks of a star with an initial mass between 28 and 33 M[SUB]⊙[/SUB] and with a critical rotational rate between 0.3 and 0.4 that has lost its material during or just after the blue supergiant phase. Based in part on observations taken by Herschel satellite. 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 detailApsidal motion in the massive binary HD 152218
Rauw, Grégor ULg; Rosu, S.; Noels-Grötsch, Arlette ULg et al

in Astronomy and Astrophysics (2016), 594(A33), 1-12

Massive binary systems are important laboratories in which to probe the properties of massive stars and stellar physics in general. In this context, we analysed optical spectroscopy and photometry of the ... [more ▼]

Massive binary systems are important laboratories in which to probe the properties of massive stars and stellar physics in general. In this context, we analysed optical spectroscopy and photometry of the eccentric short-period early-type binary HD 152218 in the young open cluster NGC 6231. We reconstructed the spectra of the individual stars using a disentangling code. The individual spectra were then compared with synthetic spectra obtained with the CMFGEN model atmosphere code. We furthermore analysed the light curve of the binary and used it to constrain the orbital inclination and to derive absolute masses of (19.8 ± 1.5) and (15.0 ± 1.1) M⊙. Combining radial velocity measurements from over 60 yr, we show that the system displays apsidal motion at a rate of (2.04 ± .24)°/yr. Solving the Clairaut-Radau equation, we used stellar evolution models, obtained with the CLES code, to compute the internal structure constants and to evaluate the theoretically predicted rate of apsidal motion as a function of stellar age and primary mass. In this way, we determine an age of 5.8 ± 0.6 Myr for HD 152218, which is towards the higher end of, but compatible with, the range of ages of the massive star population of NGC 6231 as determined from isochrone fitting. [less ▲]

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See detailArchitectures du XX ème siècle à Liège
Frankignoulle, Pierre ULg

Diverse speeche and writing (2016)

Visite organisée le 1/10/2016 à l'intention de DOCOMOMO Allemagne

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See detailLa communauté germanophone et la frontière orientale de Belgique : géohistoire et enjeux
Robelin, Cyril ULg; Brassart, Dorothée

Conference (2016, October 01)

Face aux querelles linguistiques entre Francophones et Néerlandophones qui paralysent le pays, la communauté germanophone de Belgique tente de trouver sa place dans un état multilingue. Pays de marche ... [more ▼]

Face aux querelles linguistiques entre Francophones et Néerlandophones qui paralysent le pays, la communauté germanophone de Belgique tente de trouver sa place dans un état multilingue. Pays de marche fondé lors de la Révolution de 1830, la Belgique a eu du mal à définir ses limites. Si la frontière méridionale avec la France n'est jamais vraiment remise en cause, celles du Nord et de l'Est sont davantage problématiques. La limite septentrionale fut fixée en 1839, lors du traité des XXIV articles de Londres, même si elle a eu du mal à renoncer aux bouches du Rhin ou au Limbourg. La frontière de l'Est reste épineuse. Le Grand Duché de Luxembourg demeure jusqu'à la Deuxième Guerre mondiale une revendication vive du Royaume. Celles de l'Allemagne sont également très critiquées. Pendant tout le XIXe siècle elle fut dans une large mesure largement fantasmée. Elle fut d'abord le cadre d'une expérience politique inédite, le Territoire neutre de Moresnet. Né d'un contentieux du traité de Vienne (1815), ce village et son gisement de cuivre furent coadministrés par le Royaume des Pays-Bas (puis la Belgique à partir de 1830) et la Prusse (devenue Allemagne en 1870). Pendant un siècle, ce territoire neutre réinvente totalement la notion de frontière. En effet, ici il s'agit non pas d'une ligne, mais d'une surface. Entité sans loi bien définie, elle devient un lieu totalement imaginé. Elle fut alors le havre supposé de toutes les canailles de l'Occident (« Far West » européen). Un des premiers casinos à voulu s'y installer. On a même voulu faire de Moresnet le premier territoire espérantiste du monde afin de dépasser les questions linguistiques. Les représentations de la frontière belgo-germanique sont polyformes tout au long du XIXe siècle. On la définit comme une zone de transition avec ses nombreux contrebandiers, une zone interlope (entre deux états, voire entre deux mondes comme en témoigne la présence de vampires), mais aussi une zone de fermeture avec l'avénement de l'Etat-nation et du nationalisme. A partir de 1914, elle devient un enjeu de géopolitique européenne. Il s'agit de la première frontière violée par l'Allemagne en août. Dès la fin du conflit, la Belgique souhaite annexer les districts de Moresnet, d'Eupen et de Malmedy avançant l'argument historique (ils faisaient partie des Pays-Bas espagnols) ou linguistique (Malmedy est largement francophone). A Versailles, la Belgique essaie de se faire entendre en s'appuyant avant tout sur le concours de Georges Clémenceau. Même si la délégation allemande tente de repousser cette annexion, le traité final attribue tous ces districts à la Belgique. Pour la première fois de son histoire le territoire de la Belgique s'étend. Un plébiscite est tout de même organisé en 1920, mais à main levée. L'écrasante majorité des électeurs se prononce pour un rattachement au royaume. Ils deviennent citoyens belges en 1925. Toutefois, la réorientation de cette périphérie vers Bruxelles n'est pas sans poser des problèmes techniques. Pendant les années 20 et 30, cet espace frontalier favorise l'irredentisme allemand, à tel point qu'on le nomme parfois « l'Alsace-Lorraine » belge. Ils sont même intégrés au Reich en 1940. A la fin de la Deuxième Guerre mondiale, ils font définitivement leur retour au territoire belge. L'état fait tout pour intégrer pleinement ces marges et cette communauté pleinement au sein de la société. Dans le cadre des querelles linguistiques et de la question du fédéralisme qui déchirent le royaume, les Germanophones restent discrets. Néanmoins, dans le cadre des lois linguistiques de 1963, une région de langue allemande est créée et reconnue : la Belgique reconnaît trois communautés linguistiques. Pourtant, part entière de la province de Liège, elle s'individualise au sein de la communauté culturelle germanophone de Belgique à partir des années 70 et 80, avec ses propres compétences, son gouvernement, son parlement, ses medias, sa police etc. Souvent loin du centre Bruxellois et de ses problèmes, elle semble davantage se tourner vers l'acteur européen, notamment par l'intermédiaire de l'eurorégion Rhin-Meuse. Ainsi, cette géohistoire de la frontière de l'Est et de la communauté germanophone de Belgique permet une réflexion intéressante sur les limites politiques mais aussi linguistiques à la fois à l'extérieur comme à l'intérieur du pays. Périphérie de la Belgique, elle n'en demeure pas moins un arbitre qui veut jouer pleinement son rôle au sein du Royaume et de l'Europe de demain. [less ▲]

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See detailThe Effect of Nutrients on the Degradation of Hydrocarbons in Mangrove Ecosystems by Microorganisms
Semboung Lang, Firmin ULg; Tarayre, Cédric ULg; Destain, Jacqueline ULg et al

in International Journal of Environmental Research (2016), 10(4), 583-592

Mangrove ecosystems are areas prone to various types of pollution, especially hydrocarbons. These hydrocarbons mostly stem from human activities such as spills coming from offshore oil operations, runoff ... [more ▼]

Mangrove ecosystems are areas prone to various types of pollution, especially hydrocarbons. These hydrocarbons mostly stem from human activities such as spills coming from offshore oil operations, runoff from surrounding urban areas or atmospheric deposition. This pollution causes the decline of mangroves, which results in an imbalance in the functioning of this particular ecosystem with damages to the microbiota. Biodegradation allows to restore these ecosystems. This biodegradation can only be effective in specific environmental conditions. The presence of nutrients, which stimulate bacterial growth and promote biodegradation, is a key parameter to be considered. During this experiment, we achieved biodegradation tests to assess the effect of nitrogen and phosphorus on the process. The results showed that the biodegradation rates were strongly bound to the presence of nutrients. The degradation rates depended on the medium. The treatment that reached the best rate of degradation of diesel after 10 days was the one using 20% of a nutrient solution (MSM) containing nitrogen and phosphorus. This treatment led to a maximal degradation of 84.7% ± 4.7% obtained in the flasks containing 20% of a nutrient solution (MSM) containing nitrogen and phosphorus. [less ▲]

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See detailThe Eating Context Drawing Test : clinical implications: a case study of an adolescent obese girl
Lepot, Aurélie ULg; D'Amore, Salvatore; Onnis, Luigi

Conference (2016, October 01)

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See detailTowards a large scale aqueous sol-gel synthesis of doped TiO2: Study of various metallic dopings for the photocatalytic degradation of p-nitrophenol
Mahy, Julien ULg; Lambert, Stéphanie ULg; Léonard, Géraldine ULg et al

in Journal of Photochemistry and Photobiology A : Chemistry (2016), 329

In this paper, an easy aqueous sol-gel synthesis developed previously by Mahy et al. [J. Sol-Gel Sci. Technol. (2016)] is adapted to produce highly active TiO2 catalysts doped with Fe3+, Ag+, Cu2+, Zn2 ... [more ▼]

In this paper, an easy aqueous sol-gel synthesis developed previously by Mahy et al. [J. Sol-Gel Sci. Technol. (2016)] is adapted to produce highly active TiO2 catalysts doped with Fe3+, Ag+, Cu2+, Zn2+, Cr3+, Al3+, Mn2+, and Co2+ ions and Pt metallic nanoparticles. Samples are characterized by inductively coupled plasma–atomic emission spectroscopy (ICP-AES), X-ray diffraction (XRD), Mössbauer spectroscopy, transmission electron microscopy (TEM), nitrogen adsorption–desorption measurements and diffuse reflectance spectroscopy measurements. Results show that the samples are composed of anatase-brookite TiO2 nanoparticles with a spherical shape and mean diameter of around 5-8 nm and a surface area of between about 150 - 250 m2 g-1. In each doped sample, the dopant is present in the form added during the synthesis, given that the sample has not undergone any particular treatment. Photoactivity tests show improvement in catalyst activity for Fe3+, Ag+, Cu2+, Zn2+, and Al3+ ion and Pt metallic nanoparticle dopants, while a decrease of activity is obtained for Cr3+, Mn2+ and Co2+ ion dopants. For some dopants, the activity of TiO2 doped with metallic ions and synthesized from the aqueous sol-gel process is equal or superior to the activity of the commercial photocatalyst Degussa P25. Some mechanisms are proposed to explain these modifications of activity with doping. Furthermore, cost comparison at laboratory scale showed that Zn and Cu nitrate salt dopings are clearly less expensive for a halogen light (UV/visible) or low energy light enhanced catalyst and may be considered for industrial applications. Using this method, a large scale Zn-doped TiO2 photocatalyst is synthesized with properties homologous to the lab-scale product. Results show that the aqueous sol-gel synthesis developed previously can be easily adapted for doping in order to produce an up-scalable synthesis. [less ▲]

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See detail2003 AZ84: Size, shape, albedo and first detection of topographic features
Dias-Oliveira, Alex; Sicardy, Bruno; Ortiz, Jose-Luis et al

in AAS/Division for Planetary Sciences Meeting Abstracts (2016, October 01)

We analyze two multi-chord stellar occultations by the Trans-Neptunian Object (TNO) 2003 AZ84 observed on February 3, 2012 and November 15, 2014.They provide different elliptical limb fits that are ... [more ▼]

We analyze two multi-chord stellar occultations by the Trans-Neptunian Object (TNO) 2003 AZ84 observed on February 3, 2012 and November 15, 2014.They provide different elliptical limb fits that are consistent to within their respective error bars, but could also suggest a possible precession of the object (assumed here to be a Maclaurin spheroid). The derived equatorial radius and oblateness are R[SUB]e[/SUB] = 393 ± 7 km and ɛ = 0.057 in 2014 and R[SUB]e[/SUB] = 414 ± 13 km and ɛ = 0.165 in 2012, respectively. Those results are consistent with single-chord events observed in January 2011 and December 2013. The figures above provide geometric visual albedos of p[SUB]V(2014)[/SUB] = 0.112 ± 0.008 and p[SUB]V(2012)[/SUB] = 0.114 ± 0.020. Using the Maclaurin assumption, combined with possible rotational periods of 6.67 h and 10.56 h, we estimate density upper limits of 1.89 ± 0.16g/cm[SUP]3[/SUP] and 0.77 ± 0.07g/cm[SUP]3[/SUP] for the two dates, respectively.The 2014 event provides (for the first time during a TNO occultation) a grazing chord with a gradual disappearance of the star behind 2003[SUB]AZ[/SUB]84's limb that lasts for more than 10 seconds. We rule out the possibility of a localized dust concentration as it would imply very high optical depth for that cloud. We favor a local topographic feature (chasm) with minimum width and depth of 22 ± 2.5 km and 7 ± 2.0 km, respectively. Features with similar depths are in fact observed on Pluto's main satellite, Charon, which has a radius of about 605 km, comparable to that of 2003[SUB]AZ[/SUB]84. [less ▲]

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See detailDiscovery of temperate Earth-sized planets transiting a nearby ultracool dwarf star
Jehin, Emmanuel ULg; Gillon, Michaël ULg; Lederer, Susan M. et al

in AAS/Division for Planetary Sciences Meeting Abstracts (2016, October 01)

We report the discovery of three short-period Earth-sized planets transiting a nearby ultracool dwarf star using data collected by the Liège TRAPPIST telescope, located in la Silla (Chile). TRAPPIST-1 is ... [more ▼]

We report the discovery of three short-period Earth-sized planets transiting a nearby ultracool dwarf star using data collected by the Liège TRAPPIST telescope, located in la Silla (Chile). TRAPPIST-1 is an isolated M8.0±0.5-type dwarf star at a distance of 12.0±0.4 parsecs as measured by its trigonometric parallax, with an age constrained to be > 500 Myr, and with a luminosity, mass, and radius of 0.05%, 8% and 11.5% those of the Sun, respectively. The small size of the host star, only slightly larger than Jupiter, translates into Earth-like radii for the three discovered planets, as deduced from their transit depths. The inner two planets receive four and two times the irradiation of Earth, respectively, placing them close to the inner edge of the habitable zone of the star. Several orbits remain possible for the third planet based on our current data. The infrared brightness of the host star combined with its Jupiter-like size offer the possibility of thoroughly characterizing the components of this nearby planetary system. [less ▲]

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