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See detailContribution à la détermination du profil en COVs des effluents gazeux de séchage industriel de levain
Eloundou Mballa, Pierre Patrick ULg; Fauconnier, Marie-Laure ULg

Poster (2013, July 02)

During the industrial drying of sourdough, there is an evaporation of a part of the volatile compounds and those generated during the process. These compounds are evacuated with waste and lost for the ... [more ▼]

During the industrial drying of sourdough, there is an evaporation of a part of the volatile compounds and those generated during the process. These compounds are evacuated with waste and lost for the industry. A complete characterization of the aromatic profile would open ways towards a co-valuation of some of these COVS. [less ▲]

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See detailFast-evolving weather for the coolest of our two new substellar neighbours
Gillon, Michaël ULg; Triaud, A. H. M. J.; Jehin, Emmanuel ULg et al

in Astronomy and Astrophysics (2013), 555

We present the results of an intense photometric monitoring in the near-infrared (~0.9 microns) with the TRAPPIST robotic telescope of the newly discovered binary brown dwarf WISE J104915.57-531906.1, the ... [more ▼]

We present the results of an intense photometric monitoring in the near-infrared (~0.9 microns) with the TRAPPIST robotic telescope of the newly discovered binary brown dwarf WISE J104915.57-531906.1, the third closest system to the Sun at a distance of only 2 pc. Our twelve nights of photometric time-series reveal a quasi-periodic (P = 4.87+-0.01 h) variability with a maximal peak-peak amplitude of ~11% and strong night-to-night evolution. We attribute this variability to the rotational modulation of fast-evolving weather patterns in the atmosphere of the coolest component (~T1-type) of the binary. No periodic signal is detected for the hottest component (~L8-type). For both brown dwarfs, our data allow us to firmly discard any unique transit during our observations for planets >= 2 Rearth. For orbital periods smaller than ~9.5 h, transiting planets are excluded down to an Earth-size. [less ▲]

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See detailProtein Identification and Quantification in Mixtures of highly-modified Proteins
Dobson, Rowan ULg

Doctoral thesis (2013)

The identification and quantification of proteins in highly-modified mixtures using proteomics has been performed. Two research projects have been undertaken which fulfil this aim. The first comprised the ... [more ▼]

The identification and quantification of proteins in highly-modified mixtures using proteomics has been performed. Two research projects have been undertaken which fulfil this aim. The first comprised the development of quantitative methods to detect trace amounts of hazelnut and soy in complex mixtures. A method for the detection and absolute quantification of Cor a 9, a major hazelnut (Corylus avellana) allergen was developed based on mass spectrometry. One hundred and ten hazelnut proteins were detected, five of which were allergens. The peptide chosen for quantification was from Cor a 9 (11S globulin-like protein). Two specific fragmentation reactions were chosen in multiplexed Selected Reaction Monitoring (SRM). Forty three hazelnut food processing imitation samples, varying a range of factors, such as the temperature and incubation time were analysed. A calibration curve was made for cookies. The developed method was for home-made cookies, shop-bought cookies and chocolate. The quantities of Cor a 9 in each sample were determined from the quantification of the target peptide using isotopic dilution with a heavy isotopically labelled peptide. A second peptide with two transitions was also proven to be a possible alternative as a detection method for hazelnut. The presence of soybean allergens in processed food can be detected using the mass spectrometric identification of a soybean peptide which is resistant to the heating and chemical reactions associated with food processing. The proteomic analysis of soybeans allowed the identification of 11 allergens. A method using a peptide (VFDGELQEGR) from glycinin G1 (Gly m 6.0101) was developed for the detection and semi-quantification of the allergen in food samples. Two specific fragmentation pathways were chosen in selected reaction monitoring for unambiguous identification of glycinin G1 and were: 575.3 903.4 Da and 575.3 788.4 Da. Sixteen imitation samples of processed food spiked with soybean were analyzed, where factors such as temperature and incubation time were varied, and the chosen transitions were detected. The developed method was specific for home-made cookies and a shop-bought biscuit. Semi-quantification from both cooked and uncooked cookies was demonstrated. The second comprised the identification and quantification of conotoxins in the venom of Conus textile by the use of isotope coded affinity tagging (ICAT) and label-free quantification. The extreme variety and complexity of the conotoxins has been insufficiently documented and this research demonstrates the varied nature of conotoxins found in different parts of the venom duct and their patterns of expression. Fifteen conotoxins, several with different post-translational modifications (PTMs), were identified and quantified. Distinctive patterns emerged, with the largest group of conotoxins increasing, then peaking in the central6 proximal part, before decreasing; whilst the second largest group peaked in the distal region, generally displaying nothing in the first parts. A new conotoxin, PCCSKLHDNSCCGL*, was sequenced. [less ▲]

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See detailThe EMES "ideal-type" social enterprise as a compass
Defourny, Jacques ULg

Conference (2013, July 01)

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See detailQuadratic reformulations of nonlinear binary optimization problems
Crama, Yves ULg

Conference (2013, July 01)

We consider the problem of minimizing a pseudo-Boolean function f(x), i.e., a real-valued function of 0-1 variables. Several authors have recently proposed to reduce this problem to the quadratic case by ... [more ▼]

We consider the problem of minimizing a pseudo-Boolean function f(x), i.e., a real-valued function of 0-1 variables. Several authors have recently proposed to reduce this problem to the quadratic case by expressing f(x) as min{g(x,y): y in {0,1}}, where g is a quadratic function of x and of additional binary variables y. We establish lower and upper bounds on the number of additional y-variables needed in such a reformulation, both for the general case and for the special case of symmetricfunctions like positive or negative monomials, k-out-of-n majority functions, or parity functions. [less ▲]

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See detailStratégies et représentations de l'apprentissage du français langue étrangère chez des lycéens vietnamiens : description et étude de leur rapport avec les compétences linguistiques
Nguyen, Huu Binh ULg

Doctoral thesis (2013)

Strategies that language learners use and their beliefs about language learning are fields that have interested many researchers in recent years. So, what are language learning strategies used by ... [more ▼]

Strategies that language learners use and their beliefs about language learning are fields that have interested many researchers in recent years. So, what are language learning strategies used by Vietnamese learners of French as foreign language? What are their beliefs concerning language learning? Is there any relationship between these elements and proficiency? This is what we propose to study in this doctoral work using quantitative approach with three main research tools: the Strategy Inventory for Language Learning (Oxford, 1990), the Beliefs About Language Learning Inventory (Horwitz, 1988) and a linguistic test. We start this research by meeting the important requirement of the cross-cultural validation of the adopted questionnaires. Then, statistical analysis (descriptive and inferential) will allow us to answer to research questions. The results show that Vietnamese learners have limited and varied strategy use and they have different beliefs about the learning of French as a foreign language. Furthermore, the relationship between strategy use and representations, on the one hand, and between these elements and proficiency, on the other hand, is statistically significant. However, it is fairly complex. To conclude this thesis, we will try to provide possible explanations and point out implications. This discussion will lead to some recommendations aimed at different players involved in the teaching/learning of French in Vietnam. [less ▲]

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See detailComparison Between Morningstar Ratings and Traditional Performance Measures Ratings
Sougné, Danielle ULg; Bodson, Laurent ULg

Conference (2013, July 01)

We compare Morningstar ratings and ratings obtained using the same methodology of rating attribution with a set of commonly used performance measures. We study three types of investment horizons : 3-year ... [more ▼]

We compare Morningstar ratings and ratings obtained using the same methodology of rating attribution with a set of commonly used performance measures. We study three types of investment horizons : 3-year, 5-year and 10-year ratings. Our analysis focuses on Open-End US Mutual Funds available in Morningstar Direct Database from which we create three sets of 16,617, 13,505 and 7,992 funds corresponding respectively to the three investment horizons analyzed. Our results show that Morningstar ratings are very close ( correlation around 80%) to ratings obtained with Sharpe's alpha, Jensen's alpha, Four-factor alpha and Excess returns. [less ▲]

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See detailVirtual Reality as a Complementary Therapy to Sexual Addiction Treatment
Cismaru Inescu, Adina ULg; Andrianne, Robert ULg; Triffaux, Jean-Marc ULg

in International Journal of Advanced Computer Science (2013), 3(7),

Virtual reality has gained traction as a research, education and treatment tool. Virtual reality is a system that immerses people in virtual worlds and improves clinicians’ traditional treatments for ... [more ▼]

Virtual reality has gained traction as a research, education and treatment tool. Virtual reality is a system that immerses people in virtual worlds and improves clinicians’ traditional treatments for addictive disorders, eating disorders, phobias, and stroke rehabilitation. Sex addiction is a dysregulation of sexual desire, characterized by excessive sexual behavior (between 5-15 sexual activities/day, for more than 6 months, after the age of 15). Hypersexuality highlights disturbances in human sexual desire, motivation, and behavior systems. Virtual reality worlds were initially designed to treat smokers and alcoholics, and are now programmed for drug users and other kind of addictions. In this article we present different characteristics of sex addiction and possible treatments, including the virtual exposure treatment. [less ▲]

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See detailX-ray properties of the young open clusters HM1 and IC 2944/2948
Nazé, Yaël ULg; Rauw, Grégor ULg; Sana, H. et al

in Astronomy and Astrophysics (2013), 555

Using XMM-Newton data, we study for the first time the X-ray emission of HM1 and IC 2944/2948. Low-mass, pre-main-sequence objects with an age of a few Myr are detected, as well as a few background or ... [more ▼]

Using XMM-Newton data, we study for the first time the X-ray emission of HM1 and IC 2944/2948. Low-mass, pre-main-sequence objects with an age of a few Myr are detected, as well as a few background or foreground objects. Most massive stars in both clusters display the usual high-energy properties of that type of objects, though with log [L[SUB]X[/SUB]/L[SUB]BOL[/SUB]] apparently lower in HM1 than in IC 2944/2948. Compared with studies of other clusters, it seems that a low signal-to-noise ratio at soft energies, due to the high extinction, may be the main cause of this difference. In HM1, the two Wolf-Rayet stars show contrasting behaviors: WR89 is extremely bright, but much softer than WR87. It remains to be seen whether wind-wind collisions or magnetically confined winds can explain these emissions. In IC 2944/2948, the X-ray sources concentrate around HD 101205; a group of massive stars to the north of this object is isolated, suggesting that there exist two subclusters in the field-of-view. Tables 2, 5, and Figs. 5, 9 are available in electronic form at <A href="http://www.aanda.org">http://www.aanda.org</A>Based on observations collected with XMM-Newton, an ESA Science Mission with instruments and contributions directly funded by ESA Member States and the USA (NASA).Tables 1, 3 and 4 are 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/555/A83">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/555/A83</A> [less ▲]

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See detailHD 45314: a new γ Cassiopeiae analog among Oe stars
Rauw, Grégor ULg; Nazé, Yaël ULg; Spano, M. et al

in Astronomy and Astrophysics (2013), 555

Context. Oe stars possibly form an extension to higher temperatures of the Be phenomenon, but it is still unclear whether these stars have disks. <BR /> Aims: X-ray spectra could provide hints for ... [more ▼]

Context. Oe stars possibly form an extension to higher temperatures of the Be phenomenon, but it is still unclear whether these stars have disks. <BR /> Aims: X-ray spectra could provide hints for interactions of the star with a putative surrounding disk. <BR /> Methods: We obtained XMM-Newton observations of two Oe stars, HD 45314 and HD 60848. Spectra and light curves were extracted and analysed. Optical spectra were also obtained to support the X-ray observations. <BR /> Results: We find that both stars display very different X-ray properties. Whilst HD 60848 has an X-ray spectrum and emission level typical for its spectral type, HD 45314 displays a very hard X-ray emission, dominated by a thermal plasma with kT ~ 21 keV. Furthermore, HD 45314 displays count rate variations by a factor 2 on timescales of ~ 10[SUP]3[/SUP] s and a high log (L[SUB]X[/SUB]/L[SUB]bol[/SUB]) = -6.10 ± 0.03. <BR /> Conclusions: The X-ray properties of HD 45314 indicate that this star is a new member of the class of γ Cas analogs, the first one among the original category of Oe stars. Based on observations collected with XMM-Newton, an ESA Science Mission with instruments and contributions directly funded by ESA Member States and the USA (NASA), and observations collected at the European Southern Observatory (La Silla, Chile) and the Observatoire de Haute Provence (France). [less ▲]

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See detailDiscovery of WASP-65b and WASP-75b: Two Hot Jupiters Without Highly Inflated Radii
Gómez Maqueo Chew, Y.; Faedi, F.; Pollacco, D. et al

E-print/Working paper (2013)

We report the discovery of two transiting hot Jupiters, WASP-65b (M_pl = 1.55 +/- 0.16 M_J; R_pl = 1.11 +/- 0.06 R_J), and WASP-75b (M_pl = 1.07 +/- 0.05 M_J; R_pl = 1.27 +/- 0.05 R_J). They orbit their ... [more ▼]

We report the discovery of two transiting hot Jupiters, WASP-65b (M_pl = 1.55 +/- 0.16 M_J; R_pl = 1.11 +/- 0.06 R_J), and WASP-75b (M_pl = 1.07 +/- 0.05 M_J; R_pl = 1.27 +/- 0.05 R_J). They orbit their host star every 2.311, and 2.484 days, respectively. The planet host WASP-65 is a G6 star (T_eff = 5600 K, [Fe/H] = -0.07 +/- 0.07, age > 8 Gyr); WASP-75 is an F9 star (T_eff = 6100 K, [Fe/H] = 0.07 +/- 0.09, age of 3 Gyr). WASP-65b is one of the densest known exoplanets in the mass range 0.1 and 2.0 M_J (rho_pl = 1.13 +/- 0.08 rho_J), a mass range where a large fraction of planets are found to be inflated with respect to theoretical planet models. WASP-65b is one of only a handful of planets with masses of around 1.5 M_J, a mass regime surprisingly underrepresented among the currently known hot Jupiters. The radius of Jupiter-mass WASP-75b is slightly inflated (< 10%) as compared to theoretical planet models with no core, and has a density similar to that of Saturn (rho_pl = 0.52 +/- 0.06 rho_J). [less ▲]

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See detailForbidden oxygen lines in comets at various heliocentric distances
Decock, Alice ULg; Jehin, Emmanuel ULg; Hutsemekers, Damien ULg et al

in Astronomy and Astrophysics (2013), 555

We present a study of the three forbidden oxygen lines [OI] located in the optical region - i.e., 5577.339 Å (the green line), 6300.304 Å and 6363.776 Å (the two red lines) - in order to better understand ... [more ▼]

We present a study of the three forbidden oxygen lines [OI] located in the optical region - i.e., 5577.339 Å (the green line), 6300.304 Å and 6363.776 Å (the two red lines) - in order to better understand the production of these atoms in cometary atmospheres. The analysis is based on 48 high-resolution and high signal-to-noise spectra collected with UVES at the ESO VLT between 2003 and 2011 referring to 12 comets of different origins observed at various heliocentric distances. The flux ratio of the green line to the sum of the two red lines is evaluated to determine the parent species of the oxygen atoms by comparison with theoretical models. This analysis confirms that, at about 1 AU, H[SUB]2[/SUB]O is the main parent molecule producing oxygen atoms. At heliocentric distances >2.5 AU, this ratio changes rapidly, an indication that other molecules are starting to contribute. The most abundant species after H[SUB]2[/SUB]O in the coma, CO and CO[SUB]2[/SUB], are good candidates, and the ratio is used to estimate their abundances. We found that the CO[SUB]2[/SUB] abundance relative to H[SUB]2[/SUB]O in comet C/2001 Q4 (NEAT) observed at 4 AU can be as high as ~70%. The intrinsic widths of the oxygen lines were also measured. The green line is on average about 1 km s[SUP]-1[/SUP] broader than the red lines, while the theory predicts that the red lines are broader. This might be due to the nature of the excitation source or to a contribution of CO[SUB]2[/SUB] as the parent molecule of the 5577.339 Å line. At 4 AU, we found that the width of the green and red lines in comet C/2001 Q4 are the same, which could be explained if CO[SUB]2[/SUB] becomes the main contributor to the three [OI] lines at high heliocentric distances. Based on observations made with ESO Telescope at the La Silla Paranal Observatory under programs ID 268.C-5570, 270.C-5043, 073.C-0525, 274.C-5015, 075.C-0355, 080.C-0615, 280.C-5053, 086.C-0958, and 087.C-0929. [less ▲]

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See detailLuhman 16AB: A Remarkable, Variable L/T Transition Binary 2 pc from the Sun
Burgasser, A. J.; Faherty, J.; Beletsky, Y. et al

E-print/Working paper (2013)

Luhman (2013) has reported the discovery of a brown dwarf binary system only 2.01+/-0.15 pc from the Sun. The binary is well-resolved with a projected separation of 1.5", and spectroscopic observations ... [more ▼]

Luhman (2013) has reported the discovery of a brown dwarf binary system only 2.01+/-0.15 pc from the Sun. The binary is well-resolved with a projected separation of 1.5", and spectroscopic observations have identified the components as late-L and early-T dwarfs. The system exhibits several remarkable traits, including a "flux reversal", where the T dwarf is brighter over 0.9-1.3 micron but fainter at other wavelengths; and significant (~10%) short-period (~4.9 hr) photometric variability with a complex light curve. These observations suggest spatial variations in condensate cloud structure, which is known to evolve substantially across the L dwarf/T dwarf transition. Here we report preliminary results from a multi-site monitoring campaign aimed at probing the spectral and temporal properties of this source. Focusing on our spectroscopic observations, we report the first detections of NIR spectral variability, present detailed analysis of K I lines that confirm differences in condensate opacity between the components; and preliminary determinations of radial and rotational velocities based on high-resolution NIR spectroscopy. [less ▲]

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See detailSearch for a habitable terrestrial planet transiting the nearby red dwarf GJ 1214
Gillon, Michaël ULg; Demory, B.-O.; Madhusudhan, N. et al

E-print/Working paper (2013)

High-precision eclipse spectrophotometry of transiting terrestrial exoplanets represents a promising path for the first atmospheric characterizations of habitable worlds and the search for life outside ... [more ▼]

High-precision eclipse spectrophotometry of transiting terrestrial exoplanets represents a promising path for the first atmospheric characterizations of habitable worlds and the search for life outside our solar system. The detection of terrestrial planets transiting nearby late-type M-dwarfs could make this approach applicable within the next decade, with near-to-come general facilities. In this context, we previously identified GJ 1214 as a high-priority target for a transit search, as the transit probability of a habitable planet orbiting this nearby M4.5 dwarf would be significantly enhanced by the transiting nature of GJ 1214 b, the super-Earth already known to orbit the star. Basing on this observation, we have set-up an ambitious high-precision photometric monitoring of GJ 1214 with the Spitzer Space Telescope to probe its entire habitable zone in search of a transiting planet as small as Mars. We present here the results of this transit search. Unfortunately, we did not detect any second transiting planet. Assuming GJ 1214 hosts a habitable planet larger than Mars, our global analysis of the whole Spitzer dataset leads to a posterior no-transit probability >=97%. Our analysis allows us to significantly improve the characterization of GJ 1214 b, to measure its occultation depth to be 70+-35 ppm at 4.5 microns, and to constrain it to be smaller than 205ppm (3-sigma upper limit) at 3.6 microns. In agreement with the plethora of transmission measurements published so far for GJ 1214 b, these emission measurements are consistent with both a metal-rich and a cloudy hydrogen-rich atmosphere. [less ▲]

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See detailModeling the uncertainty of runoff flow path on a small agricultural watershed
Ouedraogo, Mohamar ULg

Scientific conference (2013, July 01)

Recently, many munipalities have been concerned by muddy floods in Belgium after rain events. Unfortunately they lead to many consequences related to financial and emotional aspects. For many years the ... [more ▼]

Recently, many munipalities have been concerned by muddy floods in Belgium after rain events. Unfortunately they lead to many consequences related to financial and emotional aspects. For many years the government have been trying to find solutions by helping municipalities by providing them with technical support through projects like ERRUISSOL and GISER. To implement solutions, it is necessary to be able to predict runoff flow path on agricultural watersheds. This is done by applying water flow direction algorithms on digital elevation model (DEM) built from elevation data. However, digital elevation models are not free of errors, and therefore they can impact the extracted flow path position. Our aim is to present the Monte Carlo simulation that is used to model the uncertainty of runoff flow path extracted from high resolution DEM built from terrestrial laser scanner. [less ▲]

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See detailEvidence-Based Practice et orthophonie : application aux troubles développementaux du langage
Maillart, Christelle ULg; Durieux, Nancy ULg

Conference (2013, July 01)

L’objectif de cet atelier est de familiariser les orthophonistes avec l’Evidence-Based Practice (EBP). Chaque clinicien est de façon régulière confronté à des incertitudes quant aux choix thérapeutiques ... [more ▼]

L’objectif de cet atelier est de familiariser les orthophonistes avec l’Evidence-Based Practice (EBP). Chaque clinicien est de façon régulière confronté à des incertitudes quant aux choix thérapeutiques ou aux décisions cliniques à prendre pour un patient particulier. L’EBP est une approche méthodologique qui permet de réduire cette incertitude. Elle préconise d’associer les résultats cliniquement pertinents issus de la recherche scientifique à la compétence clinique du praticien et à la situation d’un patient correctement et complètement informé (Sackett et al., 1996). L’EBP est une démarche complexe qui nécessite de maîtriser les outils de recherche d’informations, de pouvoir accéder à la littérature, d’avoir une approche critique des données disponibles et de les confronter aux caractéristiques d’un patient cible. Nous partirons de situations cliniques concrètes liées aux troubles développementaux du langage pour illustrer la démarche et aider le participant à se l’approprier. [less ▲]

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See detailMesures des flux in situ de gaz à effet de serre (N2O, CO2, H2O …) avec la station ECoFlux (Eddy Covariance Flux
Joly, Lilian; Decarpenterie, Thomas; Dumelié, Nicolas et al

Conference given outside the academic context (2013)

La concentration atmosphérique en gaz à effet de serre, responsable du réchauffement du climat, ne cesse d'augmenter depuis le début de l'ère industrielle. Les hypothèses médianes du groupe international ... [more ▼]

La concentration atmosphérique en gaz à effet de serre, responsable du réchauffement du climat, ne cesse d'augmenter depuis le début de l'ère industrielle. Les hypothèses médianes du groupe international d'experts sur le changement climatique (IPCC) prédisent un doublement de la concentration en dioxyde de carbone (CO2) avant la fin de ce siècle. De plus, la concentration d'autres gaz à effet de serre au pouvoir radiatif supérieur à celui du CO2 augmente, comme par exemple le méthane (CH4) et le protoxyde d’azote (N2O). Le N2O présente un potentiel de réchauffement d’environ 310 fois plus élevé que celui du CO2 avec une durée de vie de 120 à 150 ans. Son augmentation actuelle de 0.3% par an de sa concentration est imputable à l’activité anthropique incluant des processus industriels via l’utilisation de solvants mais surtout aux activités agricoles pour environ 70% via des processus biologiques de nitrification et dénitrification se produisant dans les sols. Afin de mieux comprendre l’effet des pratiques agricoles sur les échanges gazeux entre les sols et l’atmosphère, il faut quantifier les flux réels en fonction des différents types de sols, de pratiques culturales, de climats et d’écosystèmes. La limite actuelle de mesure de ces flux (notamment pour le N2O) réside dans la mauvaise sensibilité et stabilité des instruments de mesure en conditions de terrain. Depuis peu le GSMA (Groupe de Spectroscopie Moléculaire et Atmosphérique) a mis au point une station nommée ECoFlux (Eddy Covariance Flux) utilisant un senseur innovant reposant sur la spectrométrie laser infrarouge. Il permet de déterminer simultanément les flux in situ de N2O, CO2 et H2O par la méthode de covariance. Après une présentation du principe de la station ECoFlux, nous exposerons les résultats de deux campagnes de mesure sur des sites « grandes cultures » de suivi de gaz à effet de serre appartenant au réseau ICOS (http://www.icos-infrastructure.eu/). Nous terminerons en développant les intérêts et les modalités du déploiement de cette station sur site viticole [less ▲]

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See detailFactors affecting Tan Spot on winter wheat in the Grand-Duchy of Luxembourg
El Jarroudi, Moussa ULg; Kouadio, Louis; Beyer, Marco et al

in Journal of Plant Pathology [=JPP] (2013), s1

Tan spot caused by Drechslera tritici-repentis was identified for the first time in the Grand-Duchy of Luxembourg (GDL) in 1999 on the basis of morphological characters. In order to optimize disease ... [more ▼]

Tan spot caused by Drechslera tritici-repentis was identified for the first time in the Grand-Duchy of Luxembourg (GDL) in 1999 on the basis of morphological characters. In order to optimize disease control measures in this country, tillage methods, cultivar resistance, and fungicides effects were investigated during 1999-2009 in four sites. Over this period, only three years (i.e. 1999, 2000, and 2009) with epidemic outbreak were recorded. Field experiments showed a significant difference in disease severity between sites (P < 0.001), cultivars (P < 0.0001) and years (P < 0.001). In years with epidemic outbreak, the interaction of cultivars with non-inversion tillage, intensive winter wheat production, and favorable weather conditions caused an early outbreak of the disease and a significant severity at growth stage 83 (early dough). Non-inversion tillage was found to be a major factor increasing the tan spot severity compared to conventional tillage. Furthermore, the analysis revealed that the disease severity was related to the cultivar’s susceptibility. For cultivars with similar phenology, the severity differed between the cultivar with the highest and the one with ne lowest susceptibility by a factor of two to four. The study also showed that no fungicide (mix of triazoles and strobilurins) effect was observed in the epidemic years, except in 2000. [less ▲]

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See detailEstimating the parameters of globular cluster M 30 (NGC 7099) from time-series photometry
Kains, N.; Bramich, D. M.; Arellano Ferro, A. et al

in Astronomy and Astrophysics (2013), 555

<BR /> Aims: We present the analysis of 26 nights of V and I time-series observations from 2011 and 2012 of the globular cluster M 30 (NGC 7099). We used our data to search for variable stars in this ... [more ▼]

<BR /> Aims: We present the analysis of 26 nights of V and I time-series observations from 2011 and 2012 of the globular cluster M 30 (NGC 7099). We used our data to search for variable stars in this cluster and refine the periods of known variables; we then used our variable star light curves to derive values for the cluster's parameters. <BR /> Methods: We used difference image analysis to reduce our data to obtain high-precision light curves of variable stars. We then estimated the cluster parameters by performing a Fourier decomposition of the light curves of RR Lyrae stars for which a good period estimate was possible. We also derived an estimate for the age of the cluster by fitting theoretical isochrones to our colour-magnitude diagram (CMD). <BR /> Results: Out of 13 stars previously catalogued as variables, we find that only 4 are bona fide variables. We detect two new RR Lyrae variables, and confirm two additional RR Lyrae candidates from the literature. We also detect four other new variables, including an eclipsing blue straggler system, and an SX Phoenicis star. This amounts to a total number of confirmed variable stars in M 30 of 12. We perform Fourier decomposition of the light curves of the RR Lyrae stars to derive cluster parameters using empirical relations. We find a cluster metallicity [Fe/H][SUB]ZW[/SUB] = -2.01 ± 0.04, or [Fe/H][SUB]UVES[/SUB] = -2.11 ± 0.06, and a distance of 8.32 ± 0.20 kpc (using RR0 variables), 8.10 kpc (using one RR1 variable), and 8.35 ± 0.42 kpc (using our SX Phoenicis star detection in M 30). Fitting isochrones to the CMD, we estimate an age of 13.0 ± 1.0 Gyr for M 30. This work is based on data collected by MiNDSTEp with the Danish 1.54 m telescope at the ESO La Silla Observatory.The full light curves, an extract of which is shown in Table 2 are 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/555/A36">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/555/A36</A>Tables 8-10, and Figs. 6 and 9 are available in electronic form at <A href="http://www.aanda.org">http://www.aanda.org</A> [less ▲]

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